Mercurial > hg > Members > kono > nitros9-code
changeset 1054:a3faad87fa9f
Completed first pass of comments for the program.
| author | pwz |
|---|---|
| date | Mon, 24 Mar 2003 03:36:16 +0000 |
| parents | b5ff125a1d60 |
| children | 537443a2e0d9 |
| files | 3rdparty/packages/sierra/objs/shdw.asm |
| diffstat | 1 files changed, 2112 insertions(+), 1786 deletions(-) [+] |
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--- a/3rdparty/packages/sierra/objs/shdw.asm Thu Mar 20 20:19:53 2003 +0000 +++ b/3rdparty/packages/sierra/objs/shdw.asm Mon Mar 24 03:36:16 2003 +0000 @@ -1,1787 +1,2113 @@ -******************************************************************** -* SHDW - Kings Quest III screen rendering module?? -* $Id$ -* -* Ed. Comments Who YY/MM/DD -* ------------------------------------------------------------------ -* 0 Disassembly of original distribution PWZ 03/03/14 -* using a combination of disasm v1.6 and -* the os9tools disassembler Os9disasm -* -* Note the header shows a data size of 0 -* called from the sierra module and accesses -* data set up in that module -* -* Much credit and thanks is give to Nick Sonneveld and -* the other NAGI folks. Following his sources made it -* so much easier to document what was happening in here. - -* This source will assemble byte for byte -* to the original kq3 shdw module. -* -* Header for : shdw -* Module size: $A56 #2646 -* Module CRC : $E9E019 (Good) -* Hdr parity : $74 -* Exec. off : $0012 #18 -* Data size : $0000 #0 -* Edition : $00 #0 -* Ty/La At/Rv: $11 $81 -* Prog mod, 6809 Obj, re-ent, R/O - - - -* Disassembly by Os9disasm of shdw - - - nam shdw - ttl program module - - - ifp1 - use defsfile - endc - -tylg set Prgrm+Objct -atrv set ReEnt+rev -rev set $01 - mod eom,name,tylg,atrv,start,size - -size equ . - -Xffa9 equ $FFA9 -X01af equ $01AF pointer to state.flag -X0551 equ $0551 pointer to a linked list of picture data - - -* OS9 data area definitions - -u001a equ $001A shdw MMU block data -u002e equ $002E Load offset -u0042 equ $0042 Sierra process descriptor block -u0043 equ $0043 Sierra 2nd 8K data block -u005a equ $005A color -u005b equ $005B sbuff_drawmask -u005c equ $005C flag_control -u006b equ $006B pen_status -u009e equ $009E pos_init_x -u009f equ $009F pos_init_y -u00a0 equ $00A0 pos_final_x -u00a1 equ $00A1 pos_final_y -u00a2 equ $00A2 pen_x position -u00a3 equ $00A3 pen_y position - -* these look like gen purpose scratch vars - -u00a4 equ $00A4 -u00a5 equ $00A5 -u00a6 equ $00A6 -u00a7 equ $00A7 -u00a8 equ $00A8 -u00a9 equ $00A9 -u00aa equ $00AA -u00ab equ $00AB -u00ac equ $00AC -u00ad equ $00AD -u00ae equ $00AE -u00af equ $00AF -u00b0 equ $00B0 -u00b2 equ $00B2 -u00b3 equ $00B3 -u00e9 equ $00E9 - - -* Local Program Defines - -PICBUFF_WIDTH equ 160 -PICBUFF_HEIGHT equ 168 - - -* VIEW OBJECTS FLAGS - -O_DRAWN equ $01 * 0 - object has been drawn -O_BLKIGNORE equ $02 * 1 - ignore blocks and condition lines -O_PRIFIXED equ $04 * 2 - fixes priority agi cannot change it based on position -O_HRZNIGNORE equ $08 * 3 - ignore horizon -O_UPDATE equ $10 * 4 - update every cycle -O_CYCLE equ $20 * 5 - the object cycles -O_ANIMATE equ $40 * 6 - animated -O_BLOCK equ $80 * 7 - resting on a block -O_WATER equ $100 * 8 - only allowed on water -O_OBJIGNORE equ $200 * 9 - ignore other objects when determining contacts -O_REPOS equ $400 * 10 - set whenever a obj is repositioned -* that way the interpeter doesn't check it's next movement for one cycle -O_LAND equ $800 * 11 - only allowed on land -O_SKIPUPDATE equ $1000 * 12 - does not update obj for one cycle -O_LOOPFIXED equ $2000 * 13 - agi cannot set the loop depending on direction -O_MOTIONLESS equ $4000 * 14 - no movement. -* if position is same as position in last cycle then this flag is set. -* follow/wander code can then create a new direction -* (ie, if it hits a wall or something) -O_UNUSED equ $8000 - - -picb_size equ PICBUFF_WIDTH*PICBUFF_HEIGHT -x_max equ PICBUFF_WIDTH-1 -y_max equ PICBUFF_HEIGHT-1 - -gfx_picbuff equ $6040 screen buff low address -gbuffend equ $C940 screen buff high address - -cmd_start equ $F0 first command value - - -name equ * -L000d fcs 'shdw' - fcb $00 - -* This module is linked to in sierra - -start equ * -L0012 lbra L05fb screen init ? - lbra L0713 obj_chk_control - lbra L0175 render_pic (which calls pic_cmd_loop) - lbra L0189 pic_cmd_loop - lbra L07be obj_blit - lbra L0927 - lbra L0a0f - lbra L09d8 - lbra L040e sbuff_fill - lbra L063a - lbra L0615 - - fcc 'AGI (c) copyright 1988 SIERRA On-Line' - fcc 'CoCo3 version by Chris Iden' - fcb C$NULL - -* Twiddles with MMU -* accd is loaded by calling program -L0074 cmpa u001a compare to shdw mem block - beq L008e equal ?? no work to be done move on - orcc #IntMasks turn off interupts - sta u001a store the value passed in by a - lda u0042 get sierra process descriptor map block - sta Xffa9 map it in to $2000-$3FFF - ldu u0043 2nd 8K data block in Sierra - lda u001a load my mem block value - sta ,u save my values at address held in u0043 - stb 2,u - std Xffa9 map it to task 1 block 2 - andcc #^IntMasks restore the interupts -L008e rts we done - -L008f fcb $00 load offsets updated flag - -* binary_list[] (pic_render.c) -L0090 fdb $8000 - fdb $4000 - fdb $2000 - fdb $1000 - fdb $0800 - fdb $0400 - fdb $0200 - fdb $0100 - fdb $0080 - fdb $0040 - fdb $0020 - fdb $0010 - fdb $0008 - fdb $0004 - fdb $0002 - fdb $0001 - -* circle_data[] (pic_render.c) -L00b0 fdb $8000 - fdb $e000 - fdb $e000 - fdb $e000 - fdb $7000 - fdb $f800 - fdb $f800 - fdb $f800 - fdb $7000 - fdb $3800 - fdb $7c00 - fdb $fe00 - fdb $fe00 - fdb $fe00 - fdb $7c00 - fdb $3800 - fdb $1c00 - fdb $7f00 - fdb $ff80 - fdb $ff80 - fdb $ff80 - fdb $ff80 - fdb $ff80 - fdb $7f00 - fdb $1c00 - fdb $0e00 - fdb $3f80 - fdb $7fc0 - fdb $7fc0 - fdb $ffe0 - fdb $ffe0 - fdb $ffe0 - fdb $7fc0 - fdb $7fc0 - fdb $3f80 - fdb $1f00 - fdb $0e00 - fdb $0f80 - fdb $3fe0 - fdb $7ff0 - fdb $7ff0 - fdb $fff8 - fdb $fff8 - fdb $fff8 - fdb $fff8 - fdb $fff8 - fdb $7ff0 - fdb $7ff0 - fdb $3fe0 - fdb $0f80 - fdb $07c0 - fdb $1ff0 - fdb $3ff8 - fdb $7ffc - fdb $7ffc - fdb $fffe - fdb $fffe - fdb $fffe - fdb $fffe - fdb $fffe - fdb $7ffc - fdb $7ffc - fdb $3ff8 - fdb $1ff0 - fdb $07c0 - -* circle_list[] (pic_render.c) -* I "assume" this data is different in the file -* { 0, 1, 4, 9, 16, 25, 37, 50 } -* These run like a set of numbers**2 {0,1,2,3,4,5,~6,~7} -* ah ha these are multiples 2*(0,1,2,3,4,5,~6,~7)**2) - -L0132 fcb $00,$00 0 - fcb $00,$02 2 - fcb $00,$08 8 - fcb $00,$12 18 - fcb $00,$20 32 - fcb $00,$32 50 - fcb $00,$4a 74 - fcb $00,$64 100 - - -* select case dispatch table for pic_cmd_loop() - -L0142 fdb $01bc enable_pic_draw() - fdb $01c9 disable_pic_draw() - fdb $01d4 enable_pri_draw() - fdb $01e9 disable_pri_draw() - fdb $02de draw_y_corner() - fdb $02d1 draw_x_corner() - fdb $0309 absolute_line() - fdb $031d relative_line() - fdb $0359 pic_fill() - fdb $0211 read_pen_status() - fdb $01f4 plot_with_pen() - - -* This code adds the load offsets to the program offsets above -L0158 tst L008f,pcr test if we've loaded the offsets already - bne L0174 done once leave - inc L008f,pcr not done set the flag - lda #$0b set our index to 11 - sta u00ab stow it in mem since we are going to clobber b - leau >L0142,pcr load table head address -L016a ldd u002e get load offset set in sierra - addd ,u add the load offset - std ,u++ and stow it back, bump pointer - dec u00ab decrement the index - bne L016a ain't done go again -L0174 rts we're out of here - - -* The interaction between render_pic and pic_cmd_loop is divided -* differently in the NAGI source pic_render.c - -* render_pic() -* color = F, 4 = proirity so the note says - -L0175 ldd #$4f4f load the color - pshs d push it on the stack for the pass - lbsr L040e call sbuff_fill routine - leas 2,s reset stack to value at entry - ldd 2,s pull the next word - pshs d push it on top of the stack - lbsr L0189 call pic_cmd_loop() - leas 2,s once we return clean up stack again - rts return - -* pic_cmd_loop() (pic_render.c) -L0189 pshs y - bsr L0158 ensure load offset has been added to table address - lbsr L06fc sbuff_fill() - clra make a zero - sta u005b sbuff_drawmask - sta u006b pen_status - coma make the complement FF - sta u005a store color - - ldu 4,s - ldd 5,u - lbsr L0074 twiddle mmu - -* pic_cmd_loop() (pic_render.c) starts here - ldx X0551 given_pic_data set in pic_res.c -L01a2 lda ,x+ pic_byte -L01a4 cmpa #$ff if it's FF were done - beq L01b9 so head out - suba #cmd_start first valid cmd = F0 so subtract to get index - blo L01a2 less than F0 ignore it - cmpa #$0a check for top end - bhi L01a2 greater than FA ignore it - leau >L0142,pcr load the addr of the dispatch table - asla sign extend multiply by two for double byte offset - jsr [a,u] make the call - bra L01a4 loop again -L01b9 puls y done then fetch the y back - rts and return - -* Command $F0 change picture color and enable picture draw -* enable_pic_draw() pic_render.c -* differs slightly with pic_render.c -* don't have colour_render() -* and setting of colour_picpart -* -* x contains pic_byte -* after ldd -* a contains color -* b contains draw mask -* returns the next pic_byte in a - -L01bc ldd u005a pulls in color and sbuff_drawmask - anda #$f0 and color with $F0 - ora ,x+ or that result with the pic_byte and bump to next - orb #$0f or the sbuff_drawmask with $0F - std u005a store the updated values - lda ,x+ return value ignored so this just bumps to next pic_byte - rts - - -* Command $F1 Disable picture draw -* disable_pic_draw() -L01c9 ldd u005a pulls in color and sbuff_drawmask - ora #$0f ors color with $0F (white ??) - andb #$f0 ands draw mask with $F0 - std u005a store the updated values - lda ,x+ return value ignored so this just bumps to next pic_byte - rts - -* Command $F2 Changes priority color and enables priority draw -* enable_pri_draw -L01d4 ldd u005a pulls in color and sbuff_drawmask - anda #$0f ands color with $0F - sta u005a save color - lda ,x+ loads pic_byte and bumps to next - asla times 2 with sign extend - asla again times 2 - asla and again times 2 - asla end result is multiply pic_byte by 16 ($10) - ora u005a or that value with the modified color - orb #$f0 or the sbuff_drawmask with $F0 - std u005a store the updated values - lda ,x+ return value ignored so this just bumps to next pic_byte - rts - -* Command $F3 Disable priority draw -* diasable_pri_draw() pic_render.c -L1e9 ldd u005a pulls in color and sbuff_drawmask - ora #$f0 or the color with $F0 - andb #$0f and the sbuff_drawmask with $0F - std u005a store the updated values - lda ,x+ return value ignored so this just bumps to next pic_byte - rts - -* Command $FA plot with pen -* Logic is pic_byte >= 0xF0 in c source. -* Emailed Nick Sonneveld 3/14/ 03 - -* plot_with_pen() (pic_render.c) -L01f4 lda u006b pen_status - bita #$20 and but don't change check for pen type solid or splater ($20) - beq L0204 is splater - lda ,x+ load pic_byte (acca) from pic_code and bump pointer - cmpa #cmd_start test against $F0 if a is less than -* based on discussions with Nick this must have been a bug -* in the earlier versions of software... -* if it is less than $F0 it's just a picture byte -* fix next rev. - lblo L02ea branch to a return statement miles away (could be fixed) - sta u00a6 save our pic_byte in texture_num -L0204 lbsr L0364 call read_xy_postion - lblo L02ea far off rts - std u00a2 pen x/y position - bsr L0218 call plot_with_pen2 - bra L01f4 go again ... -* yes there is no rts here in the c source either - - -* Command $F9 Change pen size and style -* read_pen_status() pic_render.c -L0211 lda ,x+ get pic_byte - sta u006b save as pen_status - lda ,x+ return value ignored so this just bumps to next pic_byte - rts - - -* plot_with_pen2 -* Set up circle_ptr -* u00a7 = pen.size -* u00a9 = pensize x 2 -* u00ab = scratch var -* u00ad = penwidth - -L0218 ldb u006b pen_status - andb #$07 - stb u00a7 pen.size ?? save for pen_status & $07 - - clra clear a and condition codes - lslb multiply by 2 - std u00a9 pen size x 2 - leau L0132,pcr circle_list[] - ldd b,u d now holds one of the circle_list values - leau L00b0,pcr circle_data[] - leau d,u use that to index to a circle_data item -* u now is circle_ptr - -* Set up x position - clra - ldb u00a2 load pen_x position - lslb multiply by two - rola - subb u00a7 subtract the pen.size - bcc L023f outcome not less than zero move on - deca - bpl L023f if we still have pos must be 0 or > - ldd #0000 - bra L024d -L023f std u00ab store pen_x at scratch - - ldd #$0140 start with 320 - subd u00a9 subtract 2 x pen.size - cmpd u00ab pen_x to calc - bls L024d if pen_x is greater keep temp calc - ldd u00ab otherwise use pen_x - -L024d lsra divide by 2 - rorb - stb u00a2 stow at pen_x - stb u00a4 stow at pen_final_x - -* Set up y position - lda u00a3 pen_y - suba u00a7 pen.size - bcc L025c >= 0 Ok go stow it - clra otherwise less than zero so set it to 0 - bra L0268 go stow it -L025c sta u00ab store pen_y at scratch - - lda #y_max start with 167 - suba u00aa subtract 2 x pen.size - cmpa u00ab compare to pen_y calced so far - bls L0268 if pen_y > calc use calc and save it - lda u00ab otherwise use pen_y -L0268 sta u00a3 pen_y - sta u00a5 pen_final_y - - lda u00a6 texture_num - ora #$01 - sta u00a8 t ?? - - ldb u00aa 2 x pen.size - incb bump it by one - tfr b,a copy b into a - adda u00a5 add value to pen_final_y - sta u00a5 save new pen_final_y - lslb shift b left (multiply by 2) - - leax L0090,pcr binary list[] - ldd b,x use 2x pensize + 1 to index into list - std u00ad pen width ??? - -* this looks like it should have been nested for loops -* but not coded that way in pic_render.c - -* new y -L0284 leax L0090,pcr binary_list[] - -* new x -L0288 lda u006b pen_status - bita #O_UPDATE and it with $10 but don't change - bne L0298 not equal zero go on to next pen status test - ldd ,u otherwise load data at circle_ptr - anda ,x and that with first element in binary_list - bne L0298 if thats not zero go on to next pen status check - - andb 1,x and the second bytes of data at circle_ptr -* and binary_list - beq L02ba that outcome is equ zero head for next calcs - -L0298 lda u006b pen_status - bita #$20 anded with $20 but don't change - beq L02af equals zero set up and plot buffer - lda u00a8 otherwise load t (texture_num | $01) - lsra divide by 2 - bcc L02a5 no remainder save that number as t - eora #$b8 exclusive or t with$B8 -L02a5 sta u00a8 save new t - bita #O_DRAWN anded with 1 but don't change - bne L02ba not equal zero don't plot - bita #O_BLKIGNORE anded with 2 but don't change - beq L02ba does equal zero don't plot - -L02af pshs u save current u sbuff_plot uses it - ldd u00a2 load pen_x/pen_y values - std u009e save at pos_init_x/y positions - lbsr L046f head for sbuff_plot() - puls u retrieve u from before call - -L02ba inc u00a2 increment pen_x value - - leax 4,x move four bytes in the binary_list - cmpx u00ad comapre that value to pen_width - bls L0288 less or same go again - - leau 2,u bump circle_ptr to next location in circle_data[] - - lda u00a4 load pen_final_x - sta u00a2 store at pen_x - inc u00a3 bump pen_y - lda u00a3 pen_y - cmpa u00a5 compare to pen_final_y - bne L0284 not equal go do the next row - rts - - -* Command $F5 Draw an X corner -* draw_x_corner() pic_render.c -L02d1 lbsr L0364 call read_xy_pos - bcs L02ea next subs rts - std u009e save pos_init_x/y positions - lbsr L046f head for sbuff_plot() - bsr L02eb draw_corner(0) - rts - - -* Command $F4 Draw a Y corner -L02de lbsr L0364 call read_xy_pos - bcs L02ea return - std u009e save at pos_init_x/y positions - lbsr L046f head for sbuff_plot() - bsr L02f9 draw_corner(1) -L02ea rts - - - -* draw_corner() -draw_x: -L02eb lbsr L036f get_x_pos() - bcs L02ea prior subs return - sta u00a0 store as pos_final_x - ldb u009f load pos_init_y - stb u00a1 store as pos_final_y - lbsr L0421 call sbuff_xline() - -draw_y: -L02f9 lbsr L0381 get_y_pos - bcs L02ea prior subs return - stb u00a1 save pos_final_y - lda u009e load pos_init_x - sta u00a0 save pos_final_x - lbsr L0447 sbuff_yline() - bra L02eb head for draw_x - - - -* Command $F6 Absolute line -* absolute_line() -* NAGI has these out of order -* This command is before Draw X corner in their source -L0309 bsr L0364 call read_xy_pos - bcs L02ea prior subs return - std u009e save at pos_init_x/y positions - lbsr L046f head for sbuff_plot() -L0312 bsr L0364 call read_xy_pos - bcs L02ea prior subs return - std u00a0 save at pos_final_x/y and passed draw_line in d - lbsr L0394 call draw_line() - bra L0312 go again - - - -* relative_line() -L031D bsr L0364 call read_xy_pos - bcs L02ea prior subs return - std u009e save at pos_init_x/y positions - lbsr L046f head for sbuff_plot() - -* calc x -L0326 lda ,x+ get next pic_byte -* and load it in pos_data in c source - cmpa #cmd_start is that equal $F0 or greater - bcc L02ea yep were done so return (we use prior subs return ??) -* that rascal in acca changes names again to x_step -* but it's still the same old data - anda #$70 and that with $70 -* (where these values are derived from I haven't a clue, as of yet :-)) - lsra divide by 2 - lsra and again - lsra once more - lsra and finally another for a /16 - ldb -1,x get the original value - bpl L0337 if original value not negative move on - nega else it was so flip the sign of the computed value -L0337 adda u009e add pos_init_x position - cmpa #x_max compare to 159 - bls L033f if it's less or same move on - lda #x_max else cap it at 159 -L033f sta u00a0 store as pos_final_x - -* calc y -* not quite the same as pic_render.c almost -* we've go the pic_byte ... er pos_data ... now called y_step -* in b so lets calc the y_step - andb #$0f and with $0F (not in pic_render.c) - bitb #$08 and that with $08 but don't change - beq L034a if result = 0 move on - andb #$07 else and it with $07 - negb and negate it -L034a addb u009f add calced value to pos_init_y - cmpb #y_max compare to 167 - bls L0352 less or same move on - ldb #y_max greater ? cap it -L0352 stb u00a1 pos_final_y - -* passes pos_final_x/y in d - lbsr L0394 call draw_line() - - bra L0326 go again exit is conditinals inside loop - -* Command $F8 Fill -* pic_fill() -L0359 bsr L0364 call read_xy_pos - bcs L02ea returned a 1 head for prior subs return - std u009e save at pos_init_x/y position - lbsr L0486 call sbuff_picfill() - bra L0359 loop till we get a 1 back from read_xy_pos - -* read_xy_pos() -L0364 lbsr L036f go get x position - lblo L02ea prior subs return - lbsr L0381 go get the y position - rts - - -* get_x_pos() -L036f lda ,x+ load pic_byte - cmpa #cmd_start is it a command? - bhs L037e if so set CC - cmpa #x_max compare to 159 - bls L037b is it less or same clear CC and return - lda #x_max greater than load acca with 159 -L037b andcc #$fe clear CC ad return - rts - - -L037e orcc #1 returns a "1" - rts - -* get_y_pos() -L0381 ldb ,x+ load pic_byte - cmpb #cmd_start is it a command - blo L038b nope less than command - lda -1,x was a command load x back in acca - bra L037e go set CC -L038b cmpb #y_max compare to 167 - bls L0391 is it less or same clear CC and return - ldb #y_max greater than load accb with 167 -L0391 andcc #$fe clear CC and return - rts - - -* draw_line() pic_render.c -* while this is a void function() seems pos_final_x/y are passed in d -* -* u00a2 = x_count -* u00a3 = y_count -* u00a4 = pos_x -* u00a5 = pos_y -* u00a6 = line_x_inc -* u00a7 = line_y_inc -* u00a8 = x_component -* u00a9 = y_component -* u00aa = largest_line -* u00ab = counter - -* process straight lines -L0394 cmpb u009f compare pos_final_y with pos_init_y - lbeq L0421 if equal call sbuff_xline() and don't return here - cmpa u009e else compare with pos_init_x position - lbeq L0447 if equal call sbuff_yline() and don't return here - - ldd u009e load pos_init_x/y positions - std u00a4 store at pen_final ??? not in pic_render.c version - -* process y - lda #$01 line_y_inc - - ldb u00a1 load pos_final_y - subb u009f subtract pos_init_y - bcc L03ae greater or equal zero don't negate -* less than zero - nega flip the sign of line_y_inc - negb flip the sign of y_component - -L03ae sta u00a7 store line_y_inc - stb u00a9 store y_component - -* process x - lda #$01 line_x_inc - - ldb u00a0 load pos_final_x - subb u009e subtract pos_init_x - bcc L03bc greater or equal zero don't negate -* less than zero - nega flip the sign of line_x_inc - negb flip the sign of x_component -L03bc sta u00a6 store line_x_inc - stb u00a8 store x_component - -* compare x/y components - cmpb u00a9 compare y_component to x_component - blo L03d0 if x_component is smaller move on - - -* x >= y -* x_component is in b - stb u00ab counter - stb u00aa largest_line - lsrb divide by 2 - stb u00a3 store y_count - clra make a zero - sta u00a2 store x_count - bra L03dc move on - -* x < y -L03d0 lda u00a9 load y_component - sta u00ab stow as counter - sta u00aa stow as largest line - lsra divide by 2 - sta u00a2 store x_count - clrb make a zero - stb u00a3 store as y_count - - -* loops through the line and uses sbuff_plot to do the screen write -* y_count is in b -L03dc addb u00a9 add in the y_component - stb u00a3 and stow back as y_count - cmpb u00aa compare that with line_largest - blo L03ee if y_count >= line_largest is not the case branch - subb u00aa subtract line_largest - stb u00a3 store as y_count - ldb u00a5 load pos_y - addb u00a7 add line_y_inc - stb u00a5 stow as pos_y - -* x_count is in a -L03ee adda u00a8 add in x_component - sta u00a2 store as x_count - cmpa u00aa compare that with line_largest - blo L0400 if x_count >= line_largest is not the case branch - suba u00aa subtract line_longest - sta u00a2 store at x_count - lda u00a4 load pos_x - adda u00a6 add line_x_inc - sta u00a4 stow as pos_x - -L0400 ldd u00a4 load computed pos_x/y - std u009e store at pos_init_x/y positions - lbsr L046f head for sbuff_plot() - ldd u00a2 reload x/y_count - dec u00ab decrement counter - bne L03dc if counter not zero go again - rts - -*********************************************************************** -* end of pic_render.c - - -* sbuff_fill() sbuf_util.c -* fill color is passed in s register - -L040e pshs x save x as we use it for an index - ldu #gbuffend address to write to - ldx #picb_size $6900 bytes to write (26.25K) -* this would be picture buffer width x height - ldd 4,s since we pushed x pull our color input out of the stack -L0418 std ,--u store them and dec dest address - leax -2,x dec counter - bne L0418 loop till done - puls x fetch the x - rts return - -* no sbuff_testpattern - -* sbuff_xline() sbuff_util.c -* gets called here with pos_final_x/y in accd -* -* u00ac = x_orig - -L0421 sta u00ac stow as x_orig - cmpa u009e compare with pos_init_x position - bhs L042d if pos_final_x same or greater branch - -* otherwise init > final so swap init and final - ldb u009e load pos_init_x position - stb u00a0 save pos_final_x position - sta u009e save pos_init_x position - -L042d bsr L046f head for sbuff_plot() returns pointer in u - - ldb u00a0 load pos_final_x - subb u009e subtract pos_init_x position - beq L0442 if they are the same move on -* b now holds the loop counter len -* u is the pointer returned from sbuff_plot - leau 1,u bump the pointer one byte right -L0437 lda ,u get the the byte - ora u005b or it with sbuff_drawmmask - anda u005a and it with the color - sta ,u+ save it back and bump u to next byte - decb decrememnt the loop counter - bne L0437 done them all? Nope loop - -L0442 lda u00ac x_orig (pos_final_x) - sta u009e save at pos_init_x position - rts - - -* sbuff_yline() sbuf_util.c -* gets called here with pos_final_x/y in accd -* -* u00ac = y_orig - -L0447 stb u00ac stow as y_orig - cmpb u009f compare with pos_init_y - bhs L0453 if pos_final same or greater branch - -* otherwise init > final so swap 'em - lda u009f load pos_init_y - sta u00a1 stow as pos_final_y - stb u009f stow as pos_init_y - -L0453 bsr L046f head for sbuff_plot() returns pointer in u - ldb u00a1 load pos_final_y - subb u009f subtract pos_init_y - beq L046a if they are the same move on -* b now holds the loop counter len -* u is the pointer returned from sbuff_plot -L045b leau PICBUFF_WIDTH,u bump ptr one line up - lda ,u get the byte - ora u005b or it with sbuff_drawmmask - anda u005a and it with the color - sta ,u save it back out - decb decrement the loop counter - bne L045b done them all ? Nope loop - -L046a ldb u00ac load y_orig - stb u009f save it as pos_init_y - rts - - -* sbuff_plot() from sbuf_util.c -* according to agi.h PBUF_MULT(width) ((( (width)<<2) + (width))<<5) -* which next 3 lines equate to so the $A0 is from 2 x 5 -* pointer is returned in index reg u -L046f ldb u009f load pos_init_y - lda #$A0 according to PBUF_MULT() - mul do the math - addb u009e add pos_init_x position - adca #0000 this adds the carry bit in to a - addd #gfx_picbuff add that to the start of the screen buf $6040 - tfr d,u move this into u - lda ,u get the byte u points to - ora u005b or it with sbuff_drawmask - anda u005a and it with the color - sta ,u and stow it back at the same place - rts return - - - - -* sbuff_picfill(u8 ypos, u8 xpos) sbuf_util.c -* u005a = color -* u005b = sbuff_drawmask -* u009e = pos_init_x -* u009f = pos_init_y -* u00a0 = left -* u00a1 = right -* u00a2 = old_direction -* u00a3 = direction -* u00a4 = old_initx -* u00a5 = old_inity -* u00a6 = old_left -* u00a7 = old_right -* u00a8 = stack_left -* u00a9 = stack_right -* u00aa = toggle -* u00ab = old_toggle -* u00ac = -* u00ad = -* u00ae = color_bl -* u00af = mask_dl -* u00b0 = old_buff (word) -* u00b2 = temp (buff) -* u00b3 = -* u00e9 = - - -colorbl set $4F - - -L0486 pshs x save x - ldx #$e000 load addr to create a new stack - sts ,--x store current stack pointer there and decrement x - tfr x,s make that the stack -* s is now stack_ptr pointing to fill_stack - - ldb u009f pos_init_y - lda #$a0 set up PBUF_MULT - mul do the math - addb u009e add pos_init_x - adca #0000 add in that carry bit - addd #gfx_picbuff add the start of screen buffer $6040 - tfr d,u move this to u -* u now is pointer to screen buffer b - - - ldb u005a load color - lda u005b load sbuff_drawmask - -* next 2 lines must have been a if (sbuff_drawmask > 0) -* not in the nagi source - - lbeq L05f5 if sbuff_drawmask = 0 we're done - bpl L04b8 if not negative branch to test color - - cmpa #cmd_start comp $F0 with sbuff_drawmask - bne L04b8 not = go test color for $0F - andb #$f0 and color with $F0 - cmpb #$40 compare that to $40 (input was $4x) - lbeq L05f5 if so were done - lda #$f0 set up value for mask_dl - bra L04c2 go save it - -L04b8 andb #$0f and color with $0F - cmpb #$0f was it already $0F - lbeq L05f5 if so we're done - lda #$0f set up value for mask_dl - -L04c2 sta u00af stow as mask_dl - anda #colorbl and that with $4F - sta u00ae stow that as color_bl - lda ,u get byte at screen buffer - anda u00af and with mask_dl - cmpa u00ae compare to color_bl - lbne L05f5 not equal were done - - ldd #$FFFF push 7 $FF bytes on temp stack - pshs a,b and set stack_ptr accordingly - pshs a,b - pshs a,b - pshs a - - lda #$a1 load a with 161 - sta u00a0 stow it at left - clra make a zero - sta u00a1 stow it at right - sta u00aa stow it at toggle - inca now we want a 1 - sta u00a3 stow it at direction - -* fill a new line -L04e9 ldd u00a0 load left/right - std u00a6 stow at old_left/right - lda u00aa load toggle - sta u00ab stow at old_toggle - ldb u009e load pos_init_x - stb u00a4 store as old_initx - incb accb now becomes counter - stu u00b0 stow current screen byte as old_buff - -L04f8 lda ,u get the screen byte pointed to by u - ora u005b or it with sbuff_drawmmask - anda u005a and that with the color - sta ,u stow that back - lda ,-u get the screen byte befor that one - anda u00af and that with mask_dl - cmpa u00ae compare result with color_bl - bne L050b not equal move on - decb otherwise decrement the counter - bne L04f8 if were not at zero go again - -L050b leau 1,u since cranked to zero bump the screen pointer by one - tfr u,d move that into d - subd u00b0 subtract old_buff - addb u009e add pos_init_x - stb u00a0 stow at left - lda u009e load pos_init_x - stb u009e store left at pos_init_x - stu u00b2 temp buff - ldu u00b0 load old_buff - leau 1,u bump to the next byte - nega negate pos_init_x value - adda #x_max add that to 159 (subtract pos_init_x) - beq L0537 that's the new counter and if zero move on - -L0524 ldb ,u get that screen byte (color_old) - andb u00af and it with mask_dl - cmpb u00ae check against color_bl - bne L0537 not equal move on - ldb ,u load that byte again to do something with - orb u005b or it with sbuff_drawmmask - andb u005a and it with color - stb ,u+ stow it back and bump the pointer - deca decrement the counter - bne L0524 if we haven't hit zero go again - -L0537 tfr u,d move the screen buff ptr to d - subd u00b2 subtract that saved old pointer - decb sunbtract a 1 - addb u00a0 add in the left - stb u00a1 store as the right - lda u00a6 load old_left - cmpa #$a1 compare to 161 - beq L0577 if it is move on - - cmpb u00a7 if the new right == old right - beq L0552 then move on - bhi L0566 not equal and right > old_right -* otherwise - stb u00a4 stow right as old_initx - clr u00aa clear toggle - bra L056c head for next calc -* they were equal -L0552 lda u00a0 load a with left - cmpa u00a6 compare that to old_left - bne L0566 move on - lda #$01 set up a one - cmpa u00aa compare toggle - beq L0577 is a one ? go to locnext - sta u00aa not one ? set it to 1 - lda u00a1 load right - sta u00a4 stow it as old_initx - bra L056c head for the next calc -* right > old_right or left > old left -L0566 clr u00aa clear toggle - lda u00a7 load old right - sta u00a4 save as old_initx - -* push a bunch on our temp stack -L056c ldy u00a2 old_direction/direction - ldx u00a4 old_initx/y - ldu u00a6 old_left/right - lda u00ab old_toggle - pshs a,x,y,u push them on the stack - -locnext: -L0577 lda u00a3 load direction - sta u00a2 stow as old_direction - ldb u009f load pos_init_y - stb u00a5 stow as old_inity - -L057f addb u00a3 add direction to pos_init_y - stb u009f stow the updated pos_init_y - cmpb #y_max compare that to 167 - bhi L05c5 greater than 167 go test direction - -L0587 ldb u009f load pos_init_y - lda #$A0 according to PBUF_MULT - mul do the math - addb u009e add pos_init_x position - adca #0000 this adds the carry bit into the answer - addd #gfx_picbuff add that to the screen buff start addr $6040 - tfr d,u move it into u - lda ,u get the byte pointed to - anda u00af and with mask_dl - cmpa u00ae compare with color_bl - lbeq L04e9 if equal go fill a new line - - lda u009e load pos_init_x - ldb u00a3 load direction - cmpb u00a2 compare to old_direction - beq L05bc go comapre pos_init_x and right - tst u00aa test toggle - bne L05bc not zero go comapre pos_init_x and right - cmpa u00a8 compare pos_init_x and stack_left - blo L05bc less than stack_left go comapre pos_init_x and right - cmpa u00a9 compare it to stack_right - bhi L05bc greater than go comapre pos_init_x and right - lda u00a9 load stack_right - cmpa u00a1 compare to right - bhs L05c5 greater or equal go check direction - inca add one to stack_right - sta u009e stow as pos_init_x - -L05bc cmpa u00a1 compare updated value to right - bhs L05c5 go check directions - inca less than then increment by 1 - sta u009e stow updated value pos_init_x - bra L0587 loop for next byte - -* test direction and toggle -L05c5 lda u00a3 load direction - cmpa u00a2 compare old_direction - bne L05dc not equal go pull stacked values - tst u00aa test toggle - bne L05dc not zero go pull stack values - nega negate direction - sta u00a3 store back at direction - lda u00a0 load left - sta u009e stow as pos_init_x - ldb u00a5 load old_inity - stb u009f stow at pos_init_y - bra L05ef go grab off stack and move on - -* directions not equal -L05dc puls a,x,y,u grab the stuff off the stack - cmpa #$FF test toggle for $FF source has test of pos_init_y - beq L05f5 equal ? clean up stack and return - sty u00a2 stow old_direction/direction - stx u009e stow pos_init_x/y - stu u00a0 stow left/right - sta u00aa stow toggle - - ldb u009f load pos_init_y - stb u00a5 stow old_inity -L05ef ldx 5,s gets left right off stack - stx u00a8 stow stack_left/right - bra L057f always loop - -L05f5 lds ,s reset stack - puls x retrieve our x - rts return - -* screen initialization ?? -* this routine effective swaps postion of -* the two nibbles of the byte loaded -* and returns it to the screen - -L05fb ldx #gfx_picbuff starting low address of srceen mem -L05fe lda ,x get the first byte bit order 0,1,2,3,4,5,6,7 - clrb empty b - lsra shift one bit from a - rorb into b - lsra again - rorb - lsra and again - rorb - lsra and finally once more - rorb - stb ,x were changing x anyway so use it for temp storage - ora ,x or that with acca so now bit order from orig -* is 4,5,6,7,0,1,2,3 - sta ,x+ put it back at x and go for the next one - cmpx #gbuffend ending high address of screen mem - bcs L05fe - rts - - -L0615 leas -2,s - ldx 4,s - ldu 2,x -L061b stu ,s - beq L0637 - pshs u - lbsr L09d8 - leas 2,s - ldu ,s - ldu 4,u - pshs u - lbsr L07be obj_blit() - leas 2,s - ldu ,s - ldu 2,u - bra L061b -L0637 leas 2,s - rts - - -L063a leas -2,s - ldx 4,s - ldu ,x - beq L0651 -L0642 stu ,s - pshs u - lbsr L0a0f - leas 2,s - ldx ,s - ldu ,x - bne L0642 -L0651 leas 2,s - rts - -* From obj_picbuff.c the pri_table[172] -* ours is only 168 -pri_table -L0654 fcb $00,$00,$00,$00,$00,$00 - fcb $00,$00,$00,$00,$00,$00 - fcb $00,$00,$00,$00,$00,$00 - fcb $00,$00,$00,$00,$00,$00 - fcb $00,$00,$00,$00,$00,$00 - fcb $00,$00,$00,$00,$00,$00 - fcb $00,$00,$00,$00,$00,$00 - fcb $00,$00,$00,$00,$00,$00 - - fcb $00,$00,$00,$00,$00,$00 - fcb $00,$00,$00,$00,$00,$00 - - fcb $00,$00,$00,$00,$00,$00 - fcb $00,$00,$00,$00,$00,$00 - - fcb $00,$00,$00,$00,$00,$00 - fcb $00,$00,$00,$00,$00,$00 - - fcb $00,$00,$00,$00,$00,$00 - fcb $00,$00,$00,$00,$00,$00 - - fcb $00,$00,$00,$00,$00,$00 - fcb $00,$00,$00,$00,$00,$00 - - fcb $00,$00,$00,$00,$00,$00 - fcb $00,$00,$00,$00,$00,$00 - - fcb $00,$00,$00,$00,$00,$00 - fcb $00,$00,$00,$00,$00,$00 - - fcb $00,$00,$00,$00,$00,$00 - fcb $00,$00,$00,$00,$00,$00 - - fcb $00,$00,$00,$00,$00,$00 - fcb $00,$00,$00,$00,$00,$00 - - fcb $00,$00,$00,$00,$00,$00 - fcb $00,$00,$00,$00,$00,$00 - -* loops thru 48 bytes with a = 4 -* bumps a by one load b with 12 this -* iterates thru ten sets of twelve bytes -* bumping a by one as it goes. - -* table_init() obj_pic_buff.c -L06fc leax L0654,pcr point to data block - ldb #$30 load index 48 - lda #4 load acca = 4 -L0704 sta ,x+ save a in buffer - decb dec the inner loop counter - bne L0704 go again if loop not finished - cmpa #$0e get here when inner loop is done - bcc L0712 did we do 10 loops (e-4) - inca nope bump data byte - ldb #$0c set new counter on loops 2-10 -* to do 12 bytes and - bra L0704 have at it again -L0712 rts - - - -* obj_chk_control(VIEW *x) obj_picbuff.c -* our index reg x points to the view structure -* are 3 = x, 4 = y instead of 3-4 = x & 5-6 = y ??? -* u00a5 = flag_signal -* u00a6 = flag_water -* u005c = flag_control -* -* X01af is loaction of state.flag -* see agi.h for definition of state structure -L0713 pshs y save y - - ldx 4,s sets up mmu info - ldd 8,x - lbsr L0074 twiddle mmu - - ldb $04,x load y ??? (obj_picbuff.c has a y ??) - lda $26,x load flags - bita #O_PRIFIXED and with $04 but don't change - bne L072f not zero move on -* it is zero then - leau L0654,pcr load buffer address - clra clear a since we will use d as an index - lda d,u fetch the data from pri_table - sta $24,x save as priority - -L072f lda #$A0 according to PBUF_MULT() - mul do the math - addb $03,x add in x ?? - adca #0000 add in the carry bit - addd #gfx_picbuff add it to the start of the screen buff addr 6040 - tfr d,u move the pointer pb to u - - ldy $10,x load y with cel_data ptr - clra make a zero - sta u00a6 stow it at flag_water - sta u00a5 stow it at flag_signal - inca make a 1 - sta u005c stow it at flag_contro1 - ldb $24,x load priority - cmpb #$0F compare it with 15 - beq L078b If it equals 15 move on -* otherwise if not equal 15 - sta u00a6 stow that 1 at flag_water - ldb ,y cx first byte of cel_data (cel_width) - -* do while cx != 0 - -L0752 lda ,u+ (pri) put byte at pb in acca and bump pointer - anda #$F0 and that with $F0 (obstacle ??) - beq L077a if it equals 0 set flag_control =0 and check_finish - - cmpa #$30 compare pri to 48 (water ??) - beq L0766 not equal move to end of loop - clr u00a6 clear the water flag - cmpa #$10 compare it with 16 (conditional ??) - beq L077e if equal go test for observe blocks - cmpa #$20 compare with 32 - beq L0787 - -L0766 decb decrement cx - bne L0752 not zero yet loop again - - lda $25,x load flags in acca - tst u00a6 test flag_water - bne L0776 not zero next test - bita #O_DRAWN should be O_WATER Looks like a BUG in ours - beq L078b if it equals one head for check_finish - bra L077a clear that flag control first and leave -L0776 bita #O_HRZNIGNORE should be O_LAND Looks like a BUG in ours - beq L078b - -L077a clr u005c clear flag_control - bra L078b head for check_finish - -L077e lda $26,x load flags in acca - bita #O_BLKIGNORE and with $02 but don't change - beq L077a equals zero clear flag_control and go check_finish - bra L0766 then head back in the loop - -L0787 sta u00a5 store acca at flag signal (obj_picbuff.c has =1) - bra L0766 continue with loop - - - -L078b lda $02,x load num - bne L07bb if not zero were done head out - -* flag signal test - lda u00a5 load flag_signal -* operates on F03_EGOSIGNAL - beq L079d if its zero go reset the signal -* otherwise set the flag - lda X01af load the state.flag element - ora #$10 set the bits - sta X01af save it back - bra L07a5 go test the water flag -L079d lda X01af load the state.flag element - anda #$ef reset the bits - sta X01af save it back - -* flag_water test -L07a5 lda u00a6 load flag_water - beq L07b3 if zero go reset the flag -* otherwise set it - lda X01af load the state.flag element - ora #$80 set the bits - sta X01af save it back - bra L07bb baby we're out of here -L07b3 lda X01af load the state.flag element - anda #$7f reset the bits - sta X01af save it back - -L07bb puls y retrieve our y and leave - rts - - -* obj_blit(VIEW *x) obj_blit.c -* our index reg x points to the view structure -* are 3 = x, 4 = y instead of 3-4 = x & 5-6 = y ??? -* u00a2 = cel_height -* u00a7 = cel_trans -* u00a8 = pb -* u00a9 -* u00ac -* u00ad -* u009e = view_pri - -L07be ldx $02,s - ldd $08,x - lbsr L0074 twiddle mmu - - ldu $10,x u now is a pointer to cel_data - lda $02,u cel_data[$02] loaded - bita #O_Block are we testing against a block or does $80 mean something else here? - beq L07d1 if zero skip next instruction - - lbsr L087f otherwise call obj_cell_mirror - -L07d1 ldd ,u++ load the first 2 bytes of cel_data and bump to next word -* cel_width is in acca we ignore - stb u00a2 save as cel_height -* obj_blit.c has and $0F which is a divide by 16 -* we do a multiply x 16 ??? - lda ,u+ cel_trans - asla - asla - asla - asla - sta u00a7 save as cel_tran - - lda $24,x priority - asla - asla - asla - asla - sta u009e view_pri - - ldb $04,x load the y value - subb u00a2 subtract the cel_height - incb add 1 - lda #$a0 according to PBUF_MULT() - mul do the math - addb $03,x add in the x value - adca #0000 add in the carry from multiply - addd #gfx_picbuff add this to the start of the screen buff addr $6040 - std u00a8 pb pointer to the pic buffer - ldx u00a8 load it in an index reg - - lda #$01 - sta u00ac set cel_invis to 1 and save - - bra L0800 -L07ff abx - -L0800 lda ,u+ - beq L082d - ldb -$01,u - anda #$f0 - andb #$0f - cmpa u00a7 - beq L07ff - lsra - lsra - lsra - lsra - sta u009f -L0814 lda ,x - anda #$f0 - cmpa #$20 - bls L083b - cmpa u009e - bhi L085b - lda u009e -L0822 ora u009f - sta ,x+ - clr u00ac - decb - bne L0814 - bra L0800 -L082d dec u00a2 - beq L0862 - ldx u00a8 - leax 160,x - stx u00a8 - bra L0800 -L083b stx u00ad - clra -L083e cmpx #$c8a0 - bcc L084f - leax >$00A0,x - lda ,x - anda #$f0 - cmpa #$20 - bls L083e -L084f ldx u00ad - cmpa u009e - bhi L085b - lda ,x - anda #$f0 - bra L0822 -L085b leax $01,x - decb - bne L0814 - bra L0800 -L0862 ldx $02,s - lda $02,x - bne L087e - lda u00ac - beq L0876 - lda X01af - ora #$40 - sta X01af - bra L087e -L0876 lda X01af - anda #$bf - sta X01af -L087e rts - - -* obj_cel_mirror in obj_picbuff.c -* we use different values -L087f anda #$30 - lsra - lsra - lsra - lsra - cmpa $0A,x - lbeq L0926 - pshs x,y,u - lda $0A,x - asla - asla - asla - asla - sta u00af - lda #$cf - anda 2,u - ora u00af - sta 2,u - ldy #gbuffend - ldd ,u++ - std u00a1 - lda ,u+ - asla - asla - asla - asla - sta u00a7 - stu u00b0 -L08af clrb - stb u00ab -L08b2 stb u00aa - lda ,u+ - beq L08fc - ldb -1,u - anda #$f0 - andb #$0f - cmpa u00a7 - bne L08cc - addb u00aa - bra L08b2 -L08c6 ldb ,u+ - beq L08d4 - andb #$0f -L08cc addb u00aa - stb u00aa - inc u00ab - bra L08c6 -L08d4 lda u00aa - nega - adda u00a1 - beq L08f1 -L08db suba #$0f - bls L08eb - sta u00aa - lda u00a7 - ora #$0f - sta ,y+ - lda u00aa - bra L08db -L08eb adda #$0f - ora u00a7 - sta ,y+ -L08f1 leax -1,u - ldb u00ab -L08f5 lda ,-x - sta ,y+ - decb - bne L08f5 -L08fc stb ,y+ - dec u00a2 - bne L08af - tfr y,d - subd #gbuffend - stb u00b2 - andb #$fe - tfr d,x - ldu u00b0 - ldy #gbuffend -L0913 ldd ,y++ - std ,u++ - leax -2,x - bne L0913 - lda u00b2 - lsra - bcc L0924 - lda ,y - sta ,u -L0924 puls x,y,u -L0926 rts - - -L0927 pshs y - ldx 4,s - ldd 8,x - lbsr L0074 twiddle mmu - clra - ldb 4,x - leau L0654,pcr - lda d,u - std u00a3 - ldb 36,x - andb #$0f - bne L0948 - ora 36,x - sta 36,x -L0948 pshs x - lbsr L07be obj_blit - leas 2,s - ldx 4,s - lda 36,x - cmpa #$3f - lbhi L09d5 - leau L0654,pcr - ldb u00a4 - clr u00b3 -L0962 clra - inc u00b3 - tstb - beq L096f - decb - lda d,u - cmpa u00a3 - beq L0962 -L096f ldb 4,x - lda #$a0 - mul - addb 3,x - adca #0 - addd #gfx_picbuff $6040 - tfr d,u - stu u00a8 - ldy 16,x - ldb 1,y - cmpb u00b3 - bhi L098b - stb u00b3 -L098b lda 36,x - anda #$f0 - sta u009e - ldb ,y -L0994 lda ,u - anda #$0f - ora u009e - sta ,u+ - decb - bne L0994 - dec u00b3 - beq L09d5 - ldu u00a8 - ldb ,y - decb -L09a8 leau -160,u - tfr u,x - lda ,u - anda #$0f - ora u009e - sta ,u - clra - lda d,u - anda #$0f - ora u009e - abx - sta ,x - dec u00b3 - bne L09a8 - ldb ,y - subb #2 - leau 1,u -L09ca lda ,u - anda #$0f - ora u009e - sta ,u+ - decb - bne L09ca -L09d5 puls y - rts - - -L09d8 ldu 2,s - ldd 12,u - lbsr L0074 twiddle mmu - ldu 2,s - ldd 8,u - std u00a1 - clr u00a0 - ldb 7,u - lda #$a0 - mul - addb 6,u - adca #0 - addd #gfx_picbuff $6040 - ldu 10,u -L09f5 std u00a8 - addd u00a0 - std u00ad - ldx u00a8 -L09fd ldd ,x++ - std ,u++ - cmpx u00ad - bcs L09fd - ldd u00a8 - addd #$00a0 - dec u00a2 - bne L09f5 - rts - - -L0a0f ldu 2,s - ldd 12,u - lbsr L0074 twiddle mmu - ldu 2,s - ldd 8,u - std u00a1 - clr u00a0 - ldb 7,u - lda #$a0 - mul - addb 6,u - adca #0 - addd #gfx_picbuff $6040 - ldu 10,u -L0a2c std u00a8 - addd u00a0 - std u00ad - ldx u00a8 -L0a34 ldd ,u++ - std ,x++ - cmpx u00ad - bcs L0a34 - ldd u00a8 - addd #$00a0 - dec u00a2 - bne L0a2c - rts - - fcb $00,$00,$00,$00 - fcb $00,$00,$00,$00 - fcc "shdw" - fcb $00 - - emod - -eom equ * - - end +******************************************************************** +* SHDW - Kings Quest III screen rendering module?? +* $Id$ +* +* Ed. Comments Who YY/MM/DD +* ------------------------------------------------------------------ +* 0 Disassembly of original distribution PWZ 03/03/14 +* using a combination of disasm v1.6 and +* the os9tools disassembler Os9disasm +* +* Note the header shows a data size of 0 +* called from the sierra module and accesses +* data set up in that module +* +* Much credit and thanks is give to Nick Sonneveld and +* the other NAGI folks. Following his sources made it +* so much easier to document what was happening in here. + +* This source will assemble byte for byte +* to the original kq3 shdw module. +* +* Header for : shdw +* Module size: $A56 #2646 +* Module CRC : $E9E019 (Good) +* Hdr parity : $74 +* Exec. off : $0012 #18 +* Data size : $0000 #0 +* Edition : $00 #0 +* Ty/La At/Rv: $11 $81 +* Prog mod, 6809 Obj, re-ent, R/O + + + +* Disassembly by Os9disasm of shdw + + + nam shdw + ttl program module + + + ifp1 + use defsfile + endc + +tylg set Prgrm+Objct +atrv set ReEnt+rev +rev set $01 + mod eom,name,tylg,atrv,start,size + +size equ . + +Xffa9 equ $FFA9 task 1 block 2 +X01af equ $01AF pointer to state.flag +X0551 equ $0551 pointer to a linked list of picture data + + +* OS9 data area definitions + +u001a equ $001A shdw MMU block data +u002e equ $002E Load offset +u0042 equ $0042 Sierra process descriptor block +u0043 equ $0043 Sierra 2nd 8K data block +u005a equ $005A color +u005b equ $005B sbuff_drawmask +u005c equ $005C flag_control +u006b equ $006B pen_status + +* these look like gen purpose scratch vars + +u009e equ $009E pos_init_x +u009f equ $009F pos_init_y +u00a0 equ $00A0 pos_final_x +u00a1 equ $00A1 pos_final_y +u00a2 equ $00A2 +u00a3 equ $00A3 +u00a4 equ $00A4 +u00a5 equ $00A5 +u00a6 equ $00A6 +u00a7 equ $00A7 +u00a8 equ $00A8 +u00a9 equ $00A9 +u00aa equ $00AA +u00ab equ $00AB +u00ac equ $00AC +u00ad equ $00AD +u00ae equ $00AE +u00af equ $00AF +u00b0 equ $00B0 +u00b2 equ $00B2 +u00b3 equ $00B3 + + + + +* VIEW OBJECTS FLAGS + +O_DRAWN equ $01 * 0 - object has been drawn +O_BLKIGNORE equ $02 * 1 - ignore blocks and condition lines +O_PRIFIXED equ $04 * 2 - fixes priority agi cannot change it based on position +O_HRZNIGNORE equ $08 * 3 - ignore horizon +O_UPDATE equ $10 * 4 - update every cycle +O_CYCLE equ $20 * 5 - the object cycles +O_ANIMATE equ $40 * 6 - animated +O_BLOCK equ $80 * 7 - resting on a block +O_WATER equ $100 * 8 - only allowed on water +O_OBJIGNORE equ $200 * 9 - ignore other objects when determining contacts +O_REPOS equ $400 * 10 - set whenever a obj is repositioned +* that way the interpeter doesn't check it's next movement for one cycle +O_LAND equ $800 * 11 - only allowed on land +O_SKIPUPDATE equ $1000 * 12 - does not update obj for one cycle +O_LOOPFIXED equ $2000 * 13 - agi cannot set the loop depending on direction +O_MOTIONLESS equ $4000 * 14 - no movement. +* if position is same as position in last cycle then this flag is set. +* follow/wander code can then create a new direction +* (ie, if it hits a wall or something) +O_UNUSED equ $8000 + +* Local Program Defines + +PICBUFF_WIDTH equ 160 ($A0) +PICBUFF_HEIGHT equ 168 ($A8) + +picb_size equ PICBUFF_WIDTH*PICBUFF_HEIGHT $6900 +x_max equ PICBUFF_WIDTH-1 159 ($9F) +y_max equ PICBUFF_HEIGHT-1 167 ($A7) + +gfx_picbuff equ $6040 screen buff low address +gbuffend equ gfx_picbuff+picb_size screen buff high address $C940 + +blit_end equ gfx_picbuff+$6860 + +cmd_start equ $F0 first command value + + +name equ * +L000d fcs 'shdw' + fcb $00 + +* This module is linked to in sierra + +start equ * +L0012 lbra L05fb screen init ? + lbra L0713 obj_chk_control + lbra L0175 render_pic (which calls pic_cmd_loop) + lbra L0189 pic_cmd_loop + lbra L07be obj_blit + lbra L0927 obj_add_pic_pri + lbra L0a0f blit_restore + lbra L09d8 blit_save + lbra L040e sbuff_fill + lbra L063a blitlist_draw + lbra L0615 blitlist_erase + + fcc 'AGI (c) copyright 1988 SIERRA On-Line' + fcc 'CoCo3 version by Chris Iden' + fcb C$NULL + +* Twiddles with MMU +* accd is loaded by calling program +* +* u001a = shdw mem block data +* u0042 = sierra process descriptor block +* u0043 = Sierra 2nd 8K data block + +L0074 cmpa u001a compare to shdw mem block + beq L008e equal ?? no work to be done move on + orcc #IntMasks turn off interupts + sta u001a store the value passed in by a + lda u0042 get sierra process descriptor map block + sta Xffa9 map it in to $2000-$3FFF + ldu u0043 2nd 8K data block in Sierra + lda u001a load my mem block value + sta ,u save my values at address held in u0043 + stb $02,u + std Xffa9 map it to task 1 block 2 + andcc #^IntMasks restore the interupts +L008e rts we done + +L008f fcb $00 load offsets updated flag + +* binary_list[] (pic_render.c) +L0090 fdb $8000 + fdb $4000 + fdb $2000 + fdb $1000 + fdb $0800 + fdb $0400 + fdb $0200 + fdb $0100 + fdb $0080 + fdb $0040 + fdb $0020 + fdb $0010 + fdb $0008 + fdb $0004 + fdb $0002 + fdb $0001 + +* circle_data[] (pic_render.c) +L00b0 fdb $8000 + fdb $e000 + fdb $e000 + fdb $e000 + fdb $7000 + fdb $f800 + fdb $f800 + fdb $f800 + fdb $7000 + fdb $3800 + fdb $7c00 + fdb $fe00 + fdb $fe00 + fdb $fe00 + fdb $7c00 + fdb $3800 + fdb $1c00 + fdb $7f00 + fdb $ff80 + fdb $ff80 + fdb $ff80 + fdb $ff80 + fdb $ff80 + fdb $7f00 + fdb $1c00 + fdb $0e00 + fdb $3f80 + fdb $7fc0 + fdb $7fc0 + fdb $ffe0 + fdb $ffe0 + fdb $ffe0 + fdb $7fc0 + fdb $7fc0 + fdb $3f80 + fdb $1f00 + fdb $0e00 + fdb $0f80 + fdb $3fe0 + fdb $7ff0 + fdb $7ff0 + fdb $fff8 + fdb $fff8 + fdb $fff8 + fdb $fff8 + fdb $fff8 + fdb $7ff0 + fdb $7ff0 + fdb $3fe0 + fdb $0f80 + fdb $07c0 + fdb $1ff0 + fdb $3ff8 + fdb $7ffc + fdb $7ffc + fdb $fffe + fdb $fffe + fdb $fffe + fdb $fffe + fdb $fffe + fdb $7ffc + fdb $7ffc + fdb $3ff8 + fdb $1ff0 + fdb $07c0 + +* circle_list[] (pic_render.c) +* this data is different in the file +* { 0, 1, 4, 9, 16, 25, 37, 50 } +* These run like a set of numbers**2 {0,1,2,3,4,5,~6,~7} +* ah ha these are multiples 2*(0,1,2,3,4,5,~6,~7)**2) + +L0132 fcb $00,$00 0 + fcb $00,$02 2 + fcb $00,$08 8 + fcb $00,$12 18 + fcb $00,$20 32 + fcb $00,$32 50 + fcb $00,$4a 74 + fcb $00,$64 100 + + +* select case dispatch table for pic_cmd_loop() + +L0142 fdb $01bc enable_pic_draw() + fdb $01c9 disable_pic_draw() + fdb $01d4 enable_pri_draw() + fdb $01e9 disable_pri_draw() + fdb $02de draw_y_corner() + fdb $02d1 draw_x_corner() + fdb $0309 absolute_line() + fdb $031d relative_line() + fdb $0359 pic_fill() + fdb $0211 read_pen_status() + fdb $01f4 plot_with_pen() + + +* This code adds the load offsets to the program offsets above +* +* u00ab = loop counter +* +L0158 tst L008f,pcr test if we've loaded the offsets already + bne L0174 done once leave + inc L008f,pcr not done set the flag + lda #$0b set our index to 11 + sta u00ab stow it in mem since we are going to clobber b + leau >L0142,pcr load table head address +L016a ldd u002e get load offset set in sierra + addd ,u add the load offset + std ,u++ and stow it back, bump pointer + dec u00ab decrement the index + bne L016a ain't done go again +L0174 rts we're out of here + + +* The interaction between render_pic and pic_cmd_loop is divided +* differently in the NAGI source pic_render.c + +* render_pic() +* 4 = proirity and color = F, so the note says +* so the priority is MSnibble and the color is LSnibble + +L0175 ldd #$4f4f load the color + pshs d push it on the stack for the pass + lbsr L040e call sbuff_fill routine + leas $02,s reset stack to value at entry + ldd $02,s pull the next word + pshs d push it on top of the stack + lbsr L0189 call pic_cmd_loop() + leas $02,s once we return clean up stack again + rts return + +* pic_cmd_loop() (pic_render.c) +* +* u005a = color +* u005b = sbuff_drawmask +* u006b = pen_status + +L0189 pshs y + bsr L0158 ensure load offset has been added to table address + lbsr L06fc sbuff_fill() + clra make a zero + sta u005b sbuff_drawmask + sta u006b pen_status + coma make the complement FF + sta u005a store color + + ldu 4,s get the word passed in to us on the stack + ldd 5,u pull out the required info for the mmu twiddle + lbsr L0074 twiddle mmu + +* pic_cmd_loop() (pic_render.c) starts here + ldx X0551 given_pic_data set in pic_res.c +L01a2 lda ,x+ pic_byte + +L01a4 cmpa #$ff if it's FF were done + beq L01b9 so head out + suba #cmd_start first valid cmd = F0 so subtract to get index + blo L01a2 less than F0 ignore it get next byte + cmpa #$0a check for top end + bhi L01a2 greater than FA ignore it get next byte + leau >L0142,pcr load the addr of the dispatch table + asla sign extend multiply by two for double byte offset + jsr [a,u] make the call + bra L01a4 loop again + +L01b9 puls y done then fetch the y back + rts and return + +* Command $F0 change picture color and enable picture draw +* enable_pic_draw() pic_render.c +* differs slightly with pic_render.c +* does't have colour_render() +* and setting of colour_picpart +* +* u005a = color +* u005b = sbuff_drawmask +* +* x contains pointer to given_pic_data known as the pic_byte +* after ldd +* a contains color +* b contains draw mask +* returns the next pic_byte in a + +L01bc ldd u005a pulls in color and sbuff_drawmask + anda #$f0 and color with $F0 + ora ,x+ or that result with the pic_byte and bump to next + orb #$0f or the sbuff_drawmask with $0F + std u005a store the updated values + lda ,x+ return value ignored so this just bumps to next pic_byte + rts + + +* Command $F1 Disable picture draw +* disable_pic_draw() +* +* u005a = color +* u005b = sbuff_drawmask +* x contains pointer to given_pic_data known as the pic_byte +* after ldd +* a contains color +* b contains draw mask +* returns the next pic_byte in a + +L01c9 ldd u005a pulls in color and sbuff_drawmask + ora #$0f ors color with $0F (white ??) + andb #$f0 ands draw mask with $F0 + std u005a store the updated values + lda ,x+ return value ignored so this just bumps to next pic_byte + rts + +* Command $F2 Changes priority color and enables priority draw +* enable_pri_draw() pic_render.c +* +* u005a = color +* u005b = sbuff_drawmask +* x contains pointer to given_pic_data known as the pic_byte +* after ldd +* a contains color +* b contains draw mask +* returns the next pic_byte in a + +L01d4 ldd u005a pulls in color and sbuff_drawmask + anda #$0f ands color with $0F + sta u005a save color + lda ,x+ loads pic_byte and bumps to next + asla times 2 with sign extend + asla again times 2 + asla and again times 2 + asla end result is multiply pic_byte by 16 ($10) + ora u005a or that value with the modified color + orb #$f0 or the sbuff_drawmask with $F0 + std u005a store the updated values + lda ,x+ return value ignored so this just bumps to next pic_byte + rts + +* Command $F3 Disable priority draw +* diasable_pri_draw() pic_render.c +* +* u005a = color +* u005b = sbuff_drawmask +* x contains pointer to given_pic_data known as the pic_byte +* after ldd +* a contains color +* b contains draw mask +* returns the next pic_byte in a + + +L1e9 ldd u005a pulls in color and sbuff_drawmask + ora #$f0 or the color with $F0 + andb #$0f and the sbuff_drawmask with $0F + std u005a store the updated values + lda ,x+ return value ignored so this just bumps to next pic_byte + rts + +* Command $FA plot with pen +* Logic is pic_byte >= 0xF0 in c source. +* Emailed Nick Sonneveld 3/14/ 03 +* +* u006b = pen_status +* u00a2 = pen_x position +* u00a3 = pen_y position +* u00a6 = texture_num +* +* x contains pointer to given_pic_data known as the pic_byte +* returns the next pic_byte in a + +* plot_with_pen() (pic_render.c) +L01f4 lda u006b pen_status + bita #$20 and but don't change check for pen type solid or splater ($20) + beq L0204 is splater + lda ,x+ load pic_byte (acca) from pic_code and bump pointer + cmpa #cmd_start test against $F0 if a is less than +* based on discussions with Nick this must have been a bug +* in the earlier versions of software... +* if it is less than $F0 it's just a picture byte +* fix next rev. + lblo L02ea branch to a return statement miles away (could be fixed) + sta u00a6 save our pic_byte in texture_num +L0204 lbsr L0364 call read_xy_postion + lblo L02ea far off rts + std u00a2 pen x/y position + bsr L0218 call plot_with_pen2() + bra L01f4 go again ... +* yes there is no rts here in the c source either + + +* Command $F9 Change pen size and style +* read_pen_status() pic_render.c +* +* u006b = pen_status +* +* x contains pointer to given_pic_data known as the pic_byte +* returns the next pic_byte in a + +L0211 lda ,x+ get pic_byte + sta u006b save as pen_status + lda ,x+ return value ignored so this just bumps to next pic_byte + rts + + +* plot_with_pen2() +* called from plot with pen +* Sets up circle_ptr +* +* u006b = pen_status +* u009e = pos_init_x +* u009f = pos_init_y +* u00a2 = pen_x position +* u00a3 = pen_y position +* u00a4 = pen_final_x +* u00a5 = pen_final_y +* u00a7 = pen.size +* u00a8 = t +* u00a9 = pensize x 2 +* u00aa = " +* u00ab = scratch var +* u00ac = scratch var +* u00ad = penwidth +* u00ae = " + +L0218 ldb u006b pen_status + andb #$07 + stb u00a7 pen.size ?? save for pen_status & $07 + + clra clear a and condition codes + lslb multiply by 2 + std u00a9 pen size x 2 + leau L0132,pcr circle_list[] + ldd b,u d now holds one of the circle_list values + leau L00b0,pcr circle_data[] + leau d,u use that to index to a circle_data item +* u now is circle_ptr + +* Set up x position + clra + ldb u00a2 load pen_x position + lslb multiply by two + rola + subb u00a7 subtract the pen.size + bcc L023f outcome not less than zero move on + deca + bpl L023f if we still have pos must be 0 or > + ldd #0000 + bra L024d +L023f std u00ab store pen_x at scratch + + ldd #$0140 start with 320 + subd u00a9 subtract 2 x pen.size + cmpd u00ab pen_x to calc + bls L024d if pen_x is greater keep temp calc + ldd u00ab otherwise use pen_x + +L024d lsra divide by 2 + rorb + stb u00a2 stow at pen_x + stb u00a4 stow at pen_final_x + +* Set up y position + lda u00a3 pen_y + suba u00a7 pen.size + bcc L025c >= 0 Ok go stow it + clra otherwise less than zero so set it to 0 + bra L0268 go stow it +L025c sta u00ab store pen_y at scratch + + lda #y_max start with 167 + suba u00aa subtract 2 x pen.size + cmpa u00ab compare to pen_y calced so far + bls L0268 if pen_y > calc use calc and save it + lda u00ab otherwise use pen_y +L0268 sta u00a3 pen_y + sta u00a5 pen_final_y + + lda u00a6 texture_num + ora #$01 + sta u00a8 t ?? + + ldb u00aa 2 x pen.size + incb bump it by one + tfr b,a copy b into a + adda u00a5 add value to pen_final_y + sta u00a5 save new pen_final_y + lslb shift b left (multiply by 2) + + leax L0090,pcr binary list[] + ldd b,x use 2x pensize + 1 to index into list + std u00ad pen width ??? + +* this looks like it should have been nested for loops +* but not coded that way in pic_render.c + +* new y +L0284 leax L0090,pcr binary_list[] + +* new x +L0288 lda u006b pen_status + bita #O_UPDATE and it with $10 but don't change + bne L0298 not equal zero go on to next pen status test + ldd ,u otherwise load data at circle_ptr + anda ,x and that with first element in binary_list + bne L0298 if thats not zero go on to next pen status check + + andb $01,x and the second bytes of data at circle_ptr +* and binary_list + beq L02ba that outcome is equ zero head for next calcs + +L0298 lda u006b pen_status + bita #$20 anded with $20 but don't change + beq L02af equals zero set up and plot buffer + lda u00a8 otherwise load t (texture_num | $01) + lsra divide by 2 + bcc L02a5 no remainder save that number as t + eora #$b8 exclusive or t with $B8 +L02a5 sta u00a8 save new t + bita #O_DRAWN anded with 1 but don't change + bne L02ba not equal zero don't plot + bita #O_BLKIGNORE anded with 2 but don't change + beq L02ba does equal zero don't plot + +L02af pshs u save current u sbuff_plot uses it + ldd u00a2 load pen_x/pen_y values + std u009e save at pos_init_x/y positions + lbsr L046f head for sbuff_plot() + puls u retrieve u from before call + +L02ba inc u00a2 increment pen_x value + + leax $04,x move four bytes in the binary_list + cmpx u00ad comapre that value to pen_width + bls L0288 less or same go again + + leau $02,u bump circle_ptr to next location in circle_data[] + + lda u00a4 load pen_final_x + sta u00a2 store at pen_x + inc u00a3 bump pen_y + lda u00a3 pen_y + cmpa u00a5 compare to pen_final_y + bne L0284 not equal go do the next row + rts + + +* Command $F5 Draw an X corner +* draw_x_corner() pic_render.c +* +* u009e = pos_init_x +* u009f = pos_init_y + +L02d1 lbsr L0364 call read_xy_pos + bcs L02ea next subs rts + std u009e save pos_init_x/y positions + lbsr L046f head for sbuff_plot() + bsr L02eb draw_corner(0) + rts + + +* Command $F4 Draw a Y corner +* draw_y_corner() pic_render.c +* +* u009e = pos_init_x +* u009f = pos_init_y + +L02de lbsr L0364 call read_xy_pos + bcs L02ea return + std u009e save at pos_init_x/y positions + lbsr L046f head for sbuff_plot() + bsr L02f9 draw_corner(1) +L02ea rts + + + +* draw_corner(u8 type) pic_render.c +* +* u009e = pos_init_x +* u009f = pos_init_y +* u00a0 = pos_final_x +* u00a1 = pos_final_y + +draw_x: +L02eb lbsr L036f get_x_pos() + bcs L02ea prior subs return + sta u00a0 store as pos_final_x + ldb u009f load pos_init_y + stb u00a1 store as pos_final_y + lbsr L0421 call sbuff_xline() + +draw_y: +L02f9 lbsr L0381 get_y_pos + bcs L02ea prior subs return + stb u00a1 save pos_final_y + lda u009e load pos_init_x + sta u00a0 save pos_final_x + lbsr L0447 sbuff_yline() + bra L02eb head for draw_x + + + +* Command $F6 Absolute line +* absolute_line() +* This command is before Draw X corner in nagi source +* +* u009e = pos_init_x +* u009f = pos_init_y +* u00a0 = pos_final_x +* u00a1 = pos_final_y + +L0309 bsr L0364 call read_xy_pos + bcs L02ea prior subs return + std u009e save at pos_init_x/y positions + lbsr L046f head for sbuff_plot() +L0312 bsr L0364 call read_xy_pos + bcs L02ea prior subs return + std u00a0 save at pos_final_x/y and passed draw_line in d + lbsr L0394 call draw_line() + bra L0312 go again + + + +* relative_line() +* +* u009e = pos_init_x +* u009f = pos_init_y +* u00a0 = pos_final_x +* u00a1 = pos_final_y + +L031D bsr L0364 call read_xy_pos + bcs L02ea prior subs return + std u009e save at pos_init_x/y positions + lbsr L046f head for sbuff_plot() + +* calc x +L0326 lda ,x+ get next pic_byte +* and load it in pos_data in c source + cmpa #cmd_start is that equal $F0 or greater + bcc L02ea yep were done so return (we use prior subs return ??) +* that rascal in acca changes names again to x_step +* but it's still the same old data + anda #$70 and that with $70 +* (where these values are derived from I haven't a clue, as of yet :-)) + lsra divide by 2 + lsra and again + lsra once more + lsra and finally another for a /16 + ldb -$01,x get the original value + bpl L0337 if original value not negative move on + nega else it was so flip the sign of the computed value +L0337 adda u009e add pos_init_x position + cmpa #x_max compare to 159 + bls L033f if it's less or same move on + lda #x_max else cap it at 159 +L033f sta u00a0 store as pos_final_x + +* calc y +* not quite the same as pic_render.c almost +* we've go the pic_byte ... er pos_data ... now called y_step +* in b so lets calc the y_step + andb #$0f and with $0F (not in pic_render.c) + bitb #$08 and that with $08 but don't change + beq L034a if result = 0 move on + andb #$07 else and it with $07 + negb and negate it +L034a addb u009f add calced value to pos_init_y + cmpb #y_max compare to 167 + bls L0352 less or same move on + ldb #y_max greater ? cap it +L0352 stb u00a1 pos_final_y + +* passes pos_final_x/y in d + lbsr L0394 call draw_line() + + bra L0326 go again exit is conditinals inside loop + +* Command $F8 Fill +* pic_fill() +* +* u009e = pos_init_x +* u009f = pos_init_y + +L0359 bsr L0364 call read_xy_pos + bcs L02ea returned a 1 head for prior subs return + std u009e save at pos_init_x/y position + lbsr L0486 call sbuff_picfill() + bra L0359 loop till we get a 1 back from read_xy_pos + +* read_xy_pos() +L0364 lbsr L036f go get x position + lblo L02ea prior subs return + lbsr L0381 go get the y position + rts + + +* get_x_pos() +L036f lda ,x+ load pic_byte + cmpa #cmd_start is it a command? + bhs L037e if so set CC + cmpa #x_max compare to 159 + bls L037b is it less or same clear CC and return + lda #x_max greater than load acca with 159 +L037b andcc #$fe clear CC ad return + rts + + +L037e orcc #1 returns a "1" + rts + +* get_y_pos() +L0381 ldb ,x+ load pic_byte + cmpb #cmd_start is it a command + blo L038b nope less than command + lda -$01,x was a command load x back in acca + bra L037e go set CC +L038b cmpb #y_max compare to 167 + bls L0391 is it less or same clear CC and return + ldb #y_max greater than load accb with 167 +L0391 andcc #$fe clear CC and return + rts + + +* draw_line() pic_render.c +* while this is a void function() seems pos_final_x/y are passed in d +* +* u009e = pos_init_x +* u009f = pos_init_y +* u00a0 = pos_final_x +* u00a1 = pos_final_y +* u00a2 = x_count +* u00a3 = y_count +* u00a4 = pos_x +* u00a5 = pos_y +* u00a6 = line_x_inc +* u00a7 = line_y_inc +* u00a8 = x_component +* u00a9 = y_component +* u00aa = largest_line +* u00ab = counter + +* process straight lines +L0394 cmpb u009f compare pos_final_y with pos_init_y + lbeq L0421 if equal call sbuff_xline() and don't return here + cmpa u009e else compare with pos_init_x position + lbeq L0447 if equal call sbuff_yline() and don't return here + + ldd u009e load pos_init_x/y positions + std u00a4 store at pen_final ??? not in pic_render.c version + +* process y + lda #$01 line_y_inc + + ldb u00a1 load pos_final_y + subb u009f subtract pos_init_y + bcc L03ae greater or equal zero don't negate +* less than zero + nega flip the sign of line_y_inc + negb flip the sign of y_component + +L03ae sta u00a7 store line_y_inc + stb u00a9 store y_component + +* process x + lda #$01 line_x_inc + + ldb u00a0 load pos_final_x + subb u009e subtract pos_init_x + bcc L03bc greater or equal zero don't negate +* less than zero + nega flip the sign of line_x_inc + negb flip the sign of x_component +L03bc sta u00a6 store line_x_inc + stb u00a8 store x_component + +* compare x/y components + cmpb u00a9 compare y_component to x_component + blo L03d0 if x_component is smaller move on + + +* x >= y +* x_component is in b + stb u00ab counter + stb u00aa largest_line + lsrb divide by 2 + stb u00a3 store y_count + clra make a zero + sta u00a2 store x_count + bra L03dc move on + +* x < y +L03d0 lda u00a9 load y_component + sta u00ab stow as counter + sta u00aa stow as largest line + lsra divide by 2 + sta u00a2 store x_count + clrb make a zero + stb u00a3 store as y_count + + +* loops through the line and uses sbuff_plot to do the screen write +* y_count is in b +L03dc addb u00a9 add in the y_component + stb u00a3 and stow back as y_count + cmpb u00aa compare that with line_largest + blo L03ee if y_count >= line_largest is not the case branch + subb u00aa subtract line_largest + stb u00a3 store as y_count + ldb u00a5 load pos_y + addb u00a7 add line_y_inc + stb u00a5 stow as pos_y + +* x_count is in a +L03ee adda u00a8 add in x_component + sta u00a2 store as x_count + cmpa u00aa compare that with line_largest + blo L0400 if x_count >= line_largest is not the case branch + suba u00aa subtract line_longest + sta u00a2 store at x_count + lda u00a4 load pos_x + adda u00a6 add line_x_inc + sta u00a4 stow as pos_x + +L0400 ldd u00a4 load computed pos_x/y + std u009e store at pos_init_x/y positions + lbsr L046f head for sbuff_plot() + ldd u00a2 reload x/y_count + dec u00ab decrement counter + bne L03dc if counter not zero go again + rts + +*********************************************************************** + + +* sbuff_fill() sbuf_util.c +* fill color is passed in s register + +L040e pshs x save x as we use it for an index + ldu #gbuffend address to write to + ldx #picb_size $6900 bytes to write (26.25K) +* this would be picture buffer width x height + ldd $04,s since we pushed x pull our color input out of the stack +L0418 std ,--u store them and dec dest address + leax -$02,x dec counter + bne L0418 loop till done + puls x fetch the x + rts return + + +* sbuff_xline() sbuff_util.c +* gets called here with pos_final_x/y in accd +* +* u005a = color +* u005b = sbuff_drawmask +* u009e = pos_init_x +* u009f = pos_init_y +* u00a0 = pos_final_x +* u00a1 = pos_final_y +* u00ac = x_orig + +L0421 sta u00ac stow as x_orig + cmpa u009e compare with pos_init_x position + bhs L042d if pos_final_x same or greater branch + +* otherwise init > final so swap init and final + ldb u009e load pos_init_x position + stb u00a0 save pos_final_x position + sta u009e save pos_init_x position + +L042d bsr L046f head for sbuff_plot() returns pointer in u + + ldb u00a0 load pos_final_x + subb u009e subtract pos_init_x position + beq L0442 if they are the same move on +* b now holds the loop counter len +* u is the pointer returned from sbuff_plot + leau $01,u bump the pointer one byte right +L0437 lda ,u get the the byte + ora u005b or it with sbuff_drawmmask + anda u005a and it with the color + sta ,u+ save it back and bump u to next byte + decb decrememnt the loop counter + bne L0437 done them all? Nope loop + +L0442 lda u00ac x_orig (pos_final_x) + sta u009e save at pos_init_x position + rts + + +* sbuff_yline() sbuf_util.c +* gets called here with pos_final_x/y in accd +* +* u005a = color +* u005b = sbuff_drawmask +* u009e = pos_init_x +* u009f = pos_init_y +* u00a0 = pos_final_x +* u00a1 = pos_final_y +* u00ac = y_orig + +L0447 stb u00ac stow as y_orig + cmpb u009f compare with pos_init_y + bhs L0453 if pos_final same or greater branch + +* otherwise init > final so swap 'em + lda u009f load pos_init_y + sta u00a1 stow as pos_final_y + stb u009f stow as pos_init_y + +L0453 bsr L046f head for sbuff_plot() returns pointer in u + ldb u00a1 load pos_final_y + subb u009f subtract pos_init_y + beq L046a if they are the same move on +* b now holds the loop counter len +* u is the pointer returned from sbuff_plot +L045b leau PICBUFF_WIDTH,u bump ptr one line up + lda ,u get the byte + ora u005b or it with sbuff_drawmmask + anda u005a and it with the color + sta ,u save it back out + decb decrement the loop counter + bne L045b done them all ? Nope loop + +L046a ldb u00ac load y_orig + stb u009f save it as pos_init_y + rts + + +* sbuff_plot() from sbuf_util.c +* according to agi.h PBUF_MULT(width) ((( (width)<<2) + (width))<<5) +* which next 3 lines equate to so the $A0 is from 2 x 5 +* pointer is returned in index reg u +* +* u005a = color +* u005b = sbuff_drawmask +* u009e = pos_init_x +* u009f = pos_init_y + +L046f ldb u009f load pos_init_y + lda #$A0 according to PBUF_MULT() + mul do the math + addb u009e add pos_init_x position + adca #0000 this adds the carry bit in to a + addd #gfx_picbuff add that to the start of the screen buf $6040 + tfr d,u move this into u + lda ,u get the byte u points to + ora u005b or it with sbuff_drawmask + anda u005a and it with the color + sta ,u and stow it back at the same place + rts return + + + + +* sbuff_picfill(u8 ypos, u8 xpos) sbuf_util.c +* u005a = color +* u005b = sbuff_drawmask +* u009e = pos_init_x +* u009f = pos_init_y +* u00a0 = left +* u00a1 = right +* u00a2 = old_direction +* u00a3 = direction +* u00a4 = old_initx +* u00a5 = old_inity +* u00a6 = old_left +* u00a7 = old_right +* u00a8 = stack_left +* u00a9 = stack_right +* u00aa = toggle +* u00ab = old_toggle +* u00ae = color_bl +* u00af = mask_dl +* u00b0 = old_buff (word) +* u00b2 = temp (buff) + + +colorbl set $4F +temp_stk set $E000 + +L0486 pshs x save x + ldx #temp_stk load addr to create a new stack + sts ,--x store current stack pointer there and decrement x + tfr x,s make that the stack +* s is now stack_ptr pointing to fill_stack + + ldb u009f pos_init_y + lda #$a0 set up PBUF_MULT + mul do the math + addb u009e add pos_init_x + adca #0000 add in that carry bit + addd #gfx_picbuff add the start of screen buffer $6040 + tfr d,u move this to u +* u now is pointer to screen buffer b + + + ldb u005a load color + lda u005b load sbuff_drawmask + +* next 2 lines must have been a if (sbuff_drawmask > 0) +* not in the nagi source + + lbeq L05f5 if sbuff_drawmask = 0 we're done + bpl L04b8 if not negative branch to test color + + cmpa #cmd_start comp $F0 with sbuff_drawmask + bne L04b8 not = go test color for $0F + andb #$f0 and color with $F0 + cmpb #$40 compare that to $40 (input was $4x) + lbeq L05f5 if so were done + lda #$f0 set up value for mask_dl + bra L04c2 go save it + +L04b8 andb #$0f and color with $0F + cmpb #$0f was it already $0F + lbeq L05f5 if so we're done + lda #$0f set up value for mask_dl + +L04c2 sta u00af stow as mask_dl + anda #colorbl and that with $4F + sta u00ae stow that as color_bl + lda ,u get byte at screen buffer + anda u00af and with mask_dl + cmpa u00ae compare to color_bl + lbne L05f5 not equal were done + + ldd #$FFFF push 7 $FF bytes on temp stack + pshs a,b and set stack_ptr accordingly + pshs a,b + pshs a,b + pshs a + + lda #$a1 load a with 161 + sta u00a0 stow it at left + clra make a zero + sta u00a1 stow it at right + sta u00aa stow it at toggle + inca now we want a 1 + sta u00a3 stow it at direction + +* fill a new line +L04e9 ldd u00a0 load left/right + std u00a6 stow at old_left/right + lda u00aa load toggle + sta u00ab stow at old_toggle + ldb u009e load pos_init_x + stb u00a4 store as old_initx + incb accb now becomes counter + stu u00b0 stow current screen byte as old_buff + +L04f8 lda ,u get the screen byte pointed to by u + ora u005b or it with sbuff_drawmmask + anda u005a and that with the color + sta ,u stow that back + lda ,-u get the screen byte befor that one + anda u00af and that with mask_dl + cmpa u00ae compare result with color_bl + bne L050b not equal move on + decb otherwise decrement the counter + bne L04f8 if were not at zero go again + +L050b leau 1,u since cranked to zero bump the screen pointer by one + tfr u,d move that into d + subd u00b0 subtract old_buff + addb u009e add pos_init_x + stb u00a0 stow at left + lda u009e load pos_init_x + stb u009e store left at pos_init_x + stu u00b2 temp buff + ldu u00b0 load old_buff + leau 1,u bump to the next byte + nega negate pos_init_x value + adda #x_max add that to 159 (subtract pos_init_x) + beq L0537 that's the new counter and if zero move on + +L0524 ldb ,u get that screen byte (color_old) + andb u00af and it with mask_dl + cmpb u00ae check against color_bl + bne L0537 not equal move on + ldb ,u load that byte again to do something with + orb u005b or it with sbuff_drawmmask + andb u005a and it with color + stb ,u+ stow it back and bump the pointer + deca decrement the counter + bne L0524 if we haven't hit zero go again + +L0537 tfr u,d move the screen buff ptr to d + subd u00b2 subtract that saved old pointer + decb sunbtract a 1 + addb u00a0 add in the left + stb u00a1 store as the right + lda u00a6 load old_left + cmpa #$a1 compare to 161 + beq L0577 if it is move on + + cmpb u00a7 if the new right == old right + beq L0552 then move on + bhi L0566 not equal and right > old_right +* otherwise + stb u00a4 stow right as old_initx + clr u00aa clear toggle + bra L056c head for next calc +* they were equal +L0552 lda u00a0 load a with left + cmpa u00a6 compare that to old_left + bne L0566 move on + lda #$01 set up a one + cmpa u00aa compare toggle + beq L0577 is a one ? go to locnext + sta u00aa not one ? set it to 1 + lda u00a1 load right + sta u00a4 stow it as old_initx + bra L056c head for the next calc +* right > old_right or left > old left +L0566 clr u00aa clear toggle + lda u00a7 load old right + sta u00a4 save as old_initx + +* push a bunch on our temp stack +L056c ldy u00a2 old_direction/direction + ldx u00a4 old_initx/y + ldu u00a6 old_left/right + lda u00ab old_toggle + pshs a,x,y,u push them on the stack + +locnext: +L0577 lda u00a3 load direction + sta u00a2 stow as old_direction + ldb u009f load pos_init_y + stb u00a5 stow as old_inity + +L057f addb u00a3 add direction to pos_init_y + stb u009f stow the updated pos_init_y + cmpb #y_max compare that to 167 + bhi L05c5 greater than 167 go test direction + +L0587 ldb u009f load pos_init_y + lda #$A0 according to PBUF_MULT + mul do the math + addb u009e add pos_init_x position + adca #0000 this adds the carry bit into the answer + addd #gfx_picbuff add that to the screen buff start addr $6040 + tfr d,u move it into u + lda ,u get the byte pointed to + anda u00af and with mask_dl + cmpa u00ae compare with color_bl + lbeq L04e9 if equal go fill a new line + + lda u009e load pos_init_x + ldb u00a3 load direction + cmpb u00a2 compare to old_direction + beq L05bc go comapre pos_init_x and right + tst u00aa test toggle + bne L05bc not zero go comapre pos_init_x and right + cmpa u00a8 compare pos_init_x and stack_left + blo L05bc less than stack_left go comapre pos_init_x and right + cmpa u00a9 compare it to stack_right + bhi L05bc greater than go comapre pos_init_x and right + lda u00a9 load stack_right + cmpa u00a1 compare to right + bhs L05c5 greater or equal go check direction + inca add one to stack_right + sta u009e stow as pos_init_x + +L05bc cmpa u00a1 compare updated value to right + bhs L05c5 go check directions + inca less than then increment by 1 + sta u009e stow updated value pos_init_x + bra L0587 loop for next byte + +* test direction and toggle +L05c5 lda u00a3 load direction + cmpa u00a2 compare old_direction + bne L05dc not equal go pull stacked values + tst u00aa test toggle + bne L05dc not zero go pull stack values + nega negate direction + sta u00a3 store back at direction + lda u00a0 load left + sta u009e stow as pos_init_x + ldb u00a5 load old_inity + stb u009f stow at pos_init_y + bra L05ef go grab off stack and move on + +* directions not equal +L05dc puls a,x,y,u grab the stuff off the stack + cmpa #$FF test toggle for $FF source has test of pos_init_y + beq L05f5 equal ? clean up stack and return + sty u00a2 stow old_direction/direction + stx u009e stow pos_init_x/y + stu u00a0 stow left/right + sta u00aa stow toggle + + ldb u009f load pos_init_y + stb u00a5 stow old_inity +L05ef ldx $05,s gets left right off stack + stx u00a8 stow stack_left/right + bra L057f always loop + +L05f5 lds ,s reset stack + puls x retrieve our x + rts return + +* screen initialization ?? +* this routine effective swaps postion of +* the two nibbles of the byte loaded +* and returns it to the screen + +L05fb ldx #gfx_picbuff starting low address of srceen mem +L05fe lda ,x get the first byte bit order 0,1,2,3,4,5,6,7 + clrb empty b + lsra shift one bit from a + rorb into b + lsra again + rorb + lsra and again + rorb + lsra and finally once more + rorb + stb ,x were changing x anyway so use it for temp storage + ora ,x or that with acca so now bit order from orig +* is 4,5,6,7,0,1,2,3 + sta ,x+ put it back at x and go for the next one + cmpx #gbuffend ending high address of screen mem + bcs L05fe + rts + +* our blit_struct is a bit different from the one in nagi +* +* struct blit_struct +* { +* struct blit_struct *prev; // 0-1 +* struct blit_struct *next; // 2-3 +* struct view_struct *v; // 4-5 +* s8 x; // 6 +* s8 y; // 7 +* s8 x_size; // 8 +* s8 y_size; // 9 +* u16 *buffer; // A-B +* u16 *view_data // C-D info for mmu twiddler +* +* }; + + +* blitlist_draw(BLIT *b) obj_base.c +L0615 leas -$02,s make room on the stack + ldx $04,s get the blit_struct pointer + ldu $02,x load u with pointer to next blit + +L061b stu ,s stow it on the stack + beq L0637 if it's zero we're done + pshs u push the pointer on the stack + lbsr L09d8 call blit_save() + leas $02,s get the pointer back in s + ldu ,s put it in u + ldu $04,u get the pointer to view_struct + pshs u push that on the stack and + lbsr L07be call obj_blit() + leas $02,s get the pointer back in s + ldu ,s put it in u + ldu $02,u get the pointer to the next one + bra L061b and go again + +L0637 leas $02,s clean up stack and leave + rts + +* blitlist_erase(BLIT *b) obj_base.c +* nagi has a return blitlist_free at the end + +L063a leas -$02,s make room on the stack + ldx $04,s get the blit_struct pointer + ldu ,x load u with the prev pointer + beq L0651 if it's zero we're done +L0642 stu ,s stow it on the stack + pshs u push the pointer + lbsr L0a0f call blit_restore() + leas $02,s get the pointer back in s + ldx ,s load x with the pointer + ldu ,x get the prev from that struct + bne L0642 loop again + +L0651 leas $02,s clean up stack and leave + rts + +* From obj_picbuff.c the pri_table[172] +* ours is only 168 +pri_table +L0654 fcb $00,$00,$00,$00,$00,$00 + fcb $00,$00,$00,$00,$00,$00 + fcb $00,$00,$00,$00,$00,$00 + fcb $00,$00,$00,$00,$00,$00 + fcb $00,$00,$00,$00,$00,$00 + fcb $00,$00,$00,$00,$00,$00 + fcb $00,$00,$00,$00,$00,$00 + fcb $00,$00,$00,$00,$00,$00 + + fcb $00,$00,$00,$00,$00,$00 + fcb $00,$00,$00,$00,$00,$00 + + fcb $00,$00,$00,$00,$00,$00 + fcb $00,$00,$00,$00,$00,$00 + + fcb $00,$00,$00,$00,$00,$00 + fcb $00,$00,$00,$00,$00,$00 + + fcb $00,$00,$00,$00,$00,$00 + fcb $00,$00,$00,$00,$00,$00 + + fcb $00,$00,$00,$00,$00,$00 + fcb $00,$00,$00,$00,$00,$00 + + fcb $00,$00,$00,$00,$00,$00 + fcb $00,$00,$00,$00,$00,$00 + + fcb $00,$00,$00,$00,$00,$00 + fcb $00,$00,$00,$00,$00,$00 + + fcb $00,$00,$00,$00,$00,$00 + fcb $00,$00,$00,$00,$00,$00 + + fcb $00,$00,$00,$00,$00,$00 + fcb $00,$00,$00,$00,$00,$00 + + fcb $00,$00,$00,$00,$00,$00 + fcb $00,$00,$00,$00,$00,$00 + +* loops thru 48 bytes with a = 4 +* bumps a by one load b with 12 this +* iterates thru ten sets of twelve bytes +* bumping acca by one as it goes. + +* table_init() obj_pic_buff.c +L06fc leax L0654,pcr point to data block + ldb #$30 load index 48 + lda #4 load acca = 4 +L0704 sta ,x+ save a in buffer + decb dec the inner loop counter + bne L0704 go again if loop not finished + cmpa #$0e get here when inner loop is done + bcc L0712 did we do 10 loops (e-4) + inca nope bump data byte + ldb #$0c set new counter on loops 2-10 +* to do 12 bytes and + bra L0704 have at it again +L0712 rts + + +* obj_chk_control(VIEW *x) obj_picbuff.c +* our index reg x points to the view structure +* are 3 = x, 4 = y instead of 3-4 = x & 5-6 = y ??? + +* This routine is passed a pointer to a view_structure +* from agi.h in the nagi source +* struct view_struct +*{ +* u8 step_time; // 0 +* u8 step_count; // 1 // counts down until the next step +* u8 num; // 2 + +* s16 x; // 3-4 in nagi +* s16 y; // 5-6 in nagi + + +* u8 x; // 3 in ours +* u8 y: // 4 the rest of the offsets hold true +* u8 dummy1 // 5 who knows what these are +* u8 dummy2 // 6 maybe just fillers + + +* u8 view_cur; // 7 +* u8 *view_data; // 8-9 +* +* u8 loop_cur; // A +* u8 loop_total; // B +* u8 *loop_data; // C-D +* +* u8 cel_cur; // E +* u8 cel_total; // F +* u8 *cel_data; // 10-11 +* u8 cel_prev_width; // new ones added to prevent kq4 crashing +* u8 cel_prev_height; +* //u8 *cel_data_prev;// 12-13 +* BLIT *blit; // 14-15 +* +* s16 x_prev; // 16-17 +* s16 y_prev; // 18-19 +* s16 x_size; // 1A-1B +* s16 y_size; // 1C-1D +* u8 step_size; // 1E +* u8 cycle_time; // 1F +* u8 cycle_count; // 20 // counts down till next cycle +* u8 direction; // 21 +* u8 motion; // 22 +* u8 cycle; // 23 +* u8 priority; // 24 +* u16 flags; // 25-26 +* +* //u8 unknown27; // 27 // these variables depend on the motion +* //u8 unknown28; // 28 // type set by follow ego, move, obj.. stuff +* //u8 unknown29; // 29 // like that +* //u8 unknown2A; // 2A +* +* union +* { +* struct // move_ego move_obj +* { +* s16 x; // 27 +* s16 y; // 28 +* u8 step_size; // 29 // original stepsize +* u8 flag; // 2A +* } move; +* +* struct // follow_ego +* { +* u8 step_size; // 27 +* u8 flag; // 28 +* u8 count; // 29 +* } follow; +* +* // wander +* u8 wander_count; // 27 +* +* // reverse or end of loop +* u8 loop_flag; // 27 +* }; +*}; +*typedef struct view_struct VIEW; + + +* u00a5 = flag_signal +* u00a6 = flag_water +* u005c = flag_control +* +* X01af is loaction of state.flag +* see agi.h for definition of state structure +L0713 pshs y save y + + ldx $04,s sets up mmu info + ldd $08,x load view_data passed to mmu twiddler + lbsr L0074 twiddle mmu + + ldb $04,x load y + lda $26,x load flags + bita #O_PRIFIXED and with $04 but don't change + bne L072f not zero move on +* it is zero then + leau L0654,pcr load buffer address + clra clear a since we will use d as an index + lda d,u fetch the data from pri_table + sta $24,x save as priority + +L072f lda #$A0 set up PBUF_MULT() + mul do the math + addb $03,x add in x + adca #0000 add in the carry bit + addd #gfx_picbuff add it to the start of the screen buff addr 6040 + tfr d,u move the pointer pb to u + + ldy $10,x load y with cel_data ptr + clra make a zero + sta u00a6 stow it at flag_water + sta u00a5 stow it at flag_signal + inca make a 1 + sta u005c stow it at flag_contro1 + ldb $24,x load priority + cmpb #$0F compare it with 15 + beq L078b If it equals 15 move on +* otherwise if not equal 15 + sta u00a6 stow that 1 at flag_water + ldb ,y cx first byte of cel_data (cel_width) + +* do while cx != 0 + +L0752 lda ,u+ (pri) put byte at pb in acca and bump pointer + anda #$F0 and that with $F0 (obstacle ??) + beq L077a if it equals 0 set flag_control =0 and check_finish + + cmpa #$30 compare pri to 48 (water ??) + beq L0766 not equal move to end of loop + clr u00a6 clear the water flag + cmpa #$10 compare it with 16 (conditional ??) + beq L077e if equal go test for observe blocks + cmpa #$20 compare with 32 + beq L0787 + +L0766 decb decrement cx + bne L0752 not zero yet loop again + + lda $25,x load flags in acca + tst u00a6 test flag_water + bne L0776 not zero next test + bita #O_DRAWN should be O_WATER Looks like a BUG in ours + beq L078b if it equals one head for check_finish + bra L077a clear that flag control first and leave +L0776 bita #O_HRZNIGNORE should be O_LAND Looks like a BUG in ours + beq L078b + +L077a clr u005c clear flag_control + bra L078b head for check_finish + +L077e lda $26,x load flags in acca + bita #O_BLKIGNORE and with $02 but don't change + beq L077a equals zero clear flag_control and go check_finish + bra L0766 then head back in the loop + +L0787 sta u00a5 store acca at flag signal (obj_picbuff.c has =1) + bra L0766 continue with loop + + + +L078b lda $02,x load num + bne L07bb if not zero were done head out + +* flag signal test + lda u00a5 load flag_signal +* operates on F03_EGOSIGNAL + beq L079d if its zero go reset the signal +* otherwise set the flag + lda X01af load the state.flag element + ora #$10 set the bits + sta X01af save it back + bra L07a5 go test the water flag +L079d lda X01af load the state.flag element + anda #$ef reset the bits + sta X01af save it back + +* flag_water test +L07a5 lda u00a6 load flag_water + beq L07b3 if zero go reset the flag +* otherwise set it + lda X01af load the state.flag element + ora #$80 set the bits + sta X01af save it back + bra L07bb baby we're out of here +L07b3 lda X01af load the state.flag element + anda #$7f reset the bits + sta X01af save it back + +L07bb puls y retrieve our y and leave + rts + + +* obj_blit(VIEW *v) obj_blit.c +* our index reg x points to the view structure +* are 3 = x, 4 = y instead of 3-4 = x & 5-6 = y ??? +* u00a2 = cel_height +* u00a7 = cel_trans +* u00a8 = init (pb) +* u00ac = cel_invis +* u00ad = pb_pri +* u009e = view_pri +* u009f = col + +L07be ldx $02,s pull our x pointer off the stack + ldd $08,x load d with view_data + lbsr L0074 twiddle mmu + + ldu $10,x u now is a pointer to cel_data + lda $02,u cel_data[$02] loaded + bita #O_Block are we testing against a block or does $80 mean something else here? + beq L07d1 if zero skip next instruction + + lbsr L087f otherwise call obj_cell_mirror + +L07d1 ldd ,u++ load the first 2 bytes of cel_data and bump to next word +* cel_width is in acca we ignore + stb u00a2 save as cel_height +* obj_blit.c has and $0F which is a divide by 16 +* we do a multiply x 16 ??? + lda ,u+ cel_trans + asla + asla + asla + asla + sta u00a7 save as cel_tran + + lda $24,x priority + asla shift left 4 + asla + asla + asla + sta u009e view_pri + + ldb $04,x load the y value + subb u00a2 subtract the cel_height + incb add 1 + lda #$a0 set up PBUF_MULT() + mul do the math + addb $03,x add in the x value + adca #0000 add in the carry from multiply + addd #gfx_picbuff add this to the start of the screen buff addr $6040 + std u00a8 pb pointer to the pic buffer + ldx u00a8 load it in an index reg + + lda #$01 + sta u00ac set cel_invis to 1 and save + + bra L0800 +L07ff abx bump the pb pointer + +L0800 lda ,u+ get the next "chunk" + beq L082d if zero + ldb -$01,u not zero load the same byte in accb + anda #$f0 and chunk with $F0 (col) + andb #$0f and chunk with $0F (chunk_len) + cmpa u00a7 compare with cel_trans + beq L07ff set up and go again color is trasnparent + lsra shift right 4 + lsra + lsra + lsra + sta u009f save the color + +L0814 lda ,x get the byte pointed to by pb + anda #$f0 get the priority portion + cmpa #$20 compare to $20 + bls L083b less or equal + cmpa u009e compare to view_pri + bhi L085b pb_pri > view_pri +* otherwise + lda u009e load view_pri +L0822 ora u009f or it with col + sta ,x+ store that at pb and bump the pointer + clr u00ac zero cel_invis + decb decrement chunk_len + bne L0814 not equal zero go again inner loop + bra L0800 go again outer loop + +L082d dec u00a2 decrement cel_height + beq L0862 equal zero move on out of cel_height loop + ldx u00a8 load init + leax >PICBUFF_WIDTH,x move 160 into screen + stx u00a8 stow that back as init/pb + bra L0800 go again + +L083b stx u00ad save the pointer + clra set up ch + +L083e cmpx #blit_end compare to gfx_picbuff+$6860 + bhs L084f not less than then branch out +* less than the end + leax >PICBUFF_WIDTH,x bump the pointer by 160 + lda ,x get that byte + anda #$f0 and it with $F0 + cmpa #$20 test against $20 + bls L083e less or equal go again + +L084f ldx u00ad load pb_pri + cmpa u009e compare with view_pri + bhi L085b pb_pri > view_pri + lda ,x make the next + anda #$f0 pb_pri + bra L0822 go or it with the color + +L085b leax $01,x bump the pb pointer + decb decrement chunk_len + bne L0814 not equal do middle loop again + bra L0800 go again + +L0862 ldx $02,s pull our view pointer back off the stack + lda $02,x get the num + bne L087e if not zero exit routine + lda u00ac get the cel_invis value + beq L0876 reset the flag + +* set the flag + lda X01af load the state.flag + ora #$40 set it + sta X01af stow it back + bra L087e exit routine + +* reset the flag +L0876 lda X01af load state.flag + anda #$bf clear it + sta X01af stow it +L087e rts + + +* obj_cel_mirror(View *v) in obj_picbuff.c +* we use different values from those shown nagi files +* on entry +* a contains cell_data[$02] in call from obj_blit() +* x contains pointer to view data +* u contains pointer to cel_data +* +* saves and restores x,y,u regs on exit +* +* u00a1 = width +* u00a2 = height_count +* u00a7 = trans transparent color left shifted 4 +* u00aa = tran_size ?? +* u00ab = meat_size +* u00af = loop_cur << 4 +* u00b0 = al + + +L087f anda #$30 and that with $30 (nagi has $70) + lsra shift right 4 + lsra + lsra + lsra + cmpa $0A,x compare that with loop_cur + lbeq L0926 if equal we're done + + pshs x,y,u save our view (x) what ever (y) and cel_data (u) pointers + + lda $0A,x load loop_cur + asla and shift it 4 left + asla + asla + asla + sta u00af stow it as ?? + lda #$cf load a with with $CF (nagi has $8F) + anda $02,u and that with cel[2] + ora u00af or with loop_cur<<4 + sta $02,u stow it back at cel[2] + + ldy #gbuffend + + ldd ,u++ load d with width and hieght + std u00a1 stow that + lda ,u+ load a with trans color + asla and shift left 4 + asla + asla + asla + sta u00a7 stow as trans + stu u00b0 stow u as al +L08af clrb make a zero + stb u00ab stow it as meat_size + +* nagi code has tran_size set to width and +* al&$0F subtracted from it. +* in this loop + +L08b2 stb u00aa and tran_size + + lda ,u+ load in the next cel_data byte + beq L08fc if its a zero leave loop + ldb -$01,u otherwise fetch the same data into b +* at this point a & b both have the same data byte + anda #$f0 and the a copy with $F0 + andb #$0f and the b copy with $0F + cmpa u00a7 compare byte&$F0 with trans + bne L08cc not equal branch out of loop + addb u00aa otherwise add in tran_size + bra L08b2 and loop + +L08c6 ldb ,u+ load the nbext byte and bump the pointer + beq L08d4 if it was zero move on + andb #$0f otherwise and it with $0F +L08cc addb u00aa add in tran_size + stb u00aa save it as tran_size + inc u00ab bump meat_size + bra L08c6 loop to the next byte + +L08d4 lda u00aa load tran_size + nega negate it + adda u00a1 add in the width + beq L08f1 if that is zero move on + +L08db suba #$0f subtract 15 from it + bls L08eb less or same move on + sta u00aa otherwise stow that back as tran_size + lda u00a7 fetch trans + ora #$0f or it with 15 + sta ,y+ store it at buff (gbuffend) and bump pointer + lda u00aa fetch tra_size + bra L08db loop again + +L08eb adda #$0f add 15 back into a (tran_size) + ora u00a7 or that with trans + sta ,y+ stow that at buff and bump the pointer + +L08f1 leax -$01,u set x to the last cel_data byte processed + ldb u00ab load b with the meat_size (the loop counter) +L08f5 lda ,-x copy from the cel_data end + sta ,y+ to the buff front + decb dec the counter + bne L08f5 not done loop again + +L08fc stb ,y+ on entry b should always = 0 stow that at the next buff location + dec u00a2 decrement the height_count + bne L08af not zero go again + +* now we are going to copy the backward temp buffer back to the cel + tfr y,d get the buff pointer in d + subd #gbuffend subtract the starting value of the buffer + stb u00b2 save that as the buffer size + andb #$fe make it an even number + tfr d,x transfer that to x + ldu u00b0 al cel_data pointer + ldy #gbuffend load y start of our temp buffer + +L0913 ldd ,y++ get a word + std ,u++ stow a word + leax -$02,x dec the counter by a word + bne L0913 not zero go again +* so we've moved an even number of bytes + lda u00b2 load the actual byte count + lsra divide by 2 + bcc L0924 no remainder (not odd) we're done + lda ,y otherwise move the last + sta ,u byte +L0924 puls x,y,u retrieve our x,y,u values + +L0926 rts and return to caller + + + +* obj_add_pic_pri(VIEW *v) obj_picbuff.c +* our index reg x points to the view structure +* +* u009e = priority&$F0 +* u00a3 = pri_table[y] +* u00a4 = pri_table[y] +* u00a8 = pb (word) +* u00a9 = " +* u00b3 = pri_height/height + +L0927 pshs y save the y + ldx $04,s get the the pointer to our view + ldd $08,x load d with view_data ? + lbsr L0074 twiddle mmu + +* set up d as pointer to pri_table value + clra zero a + ldb $04,x load view y value + leau L0654,pcr load pri_table address + lda d,u fetch the pri_table y data + std u00a3 stow it in a temp + ldb $24,x load priority + andb #$0f and that with $0F + bne L0948 if that equals zero move on + ora $24,x otherwise or the pri_table[y] with priority + sta $24,x stow that back as priority + +L0948 pshs x push the pointer to the view on the stack + lbsr L07be call obj_blit() + leas $02,s reset the stack + ldx $04,s get the pointer to our view + lda $24,x load priority + cmpa #$3F compare to $3F + lbhi L09d5 if greater then nothing to do head out + + leau L0654,pcr load pri_table address + ldb u00a4 fetch pri_table[y] (cx) + clr u00b3 clear pri_height +L0962 clra zero acca + inc u00b3 bump pri_hieght + tstb is pri_table[y] + beq L096f equal zero if so move on + decb dec our counter cx + lda d,u load pri_table[cx] + cmpa u00a3 compare to pri_table[y] + beq L0962 if they are equal loop again + +* set up and execute PBUF_MULT call +L096f ldb $04,x load the view->y in + lda #$a0 from pbuf mult + mul do the math + addb $03,x add in the x value + adca #0000 add in the carry + addd #gfx_picbuff add in the base address $6040 + tfr d,u move that to an index reg (pb) + stu u00a8 stow it as pb + + ldy $10,x load y with cel_data pointer + ldb $01,y get the second byte (height) + cmpb u00b3 compare to pri_height + bhi L098b greater move on + stb u00b3 otherwise save the largest as pri_height +L098b lda $24,x load the priority again + anda #$f0 and it with $F0 + sta u009e stow that for later use + +* bottom line + ldb ,y load b with the first byte in cel_data (cx) +L0994 lda ,u get the byte at our pic buff pb + anda #$0f and it with $0F + ora u009e or it with priority&F0 + sta ,u+ stow it back and bump the pointer + decb dec the loop counter cx + bne L0994 not zero go again + +* it has a height + dec u00b3 test "height" for > 1 + beq L09d5 wasn't head no more to do so head out + ldu u00a8 reset u to our pb pic buff pointer + +* the sides + ldb ,y get the first byte of cel_data + decb subtract 1 (sideoff) +L09a8 leau -$A0,u decrement pb by 160 + tfr u,x move that value into x + lda ,u get the data + anda #$0f and it with $0F + ora u009e or it priority&$F0 + sta ,u stow it back + clra zero a so we can use d as a pointer + lda d,u use "sideoff" as an index into pb + anda #$0f and that with $0F + ora u009e or that rascal with priority&$F0 + abx add that value to our x pointer + sta ,x and store it there + dec u00b3 dec the height + bne L09a8 greater than zero go again + +* the top of the box + + ldb ,y get the cel_data first byte in b + subb #$02 subtract 2 + leau $01,u bump the pb pointer +L09ca lda ,u grab the byte + anda #$0f and that with $0F + ora u009e or it with priority &$F0 + sta ,u+ stow it back and bump the pointer + decb dec our counter + bne L09ca loop if not finished + +L09d5 puls y return the y value + rts return + + + +* blit_save(BLIT *b) obj_blit.c +* our blit_struct is a bit different from the one in nagi +* +* u00a0 = zeroed and never changed cause we use the next byte :-) +* u00a1 = x_count (x_size) when cmpx ha ha +* u00a2 = y_count (y_size) +* u00a8 = pic buffer start pic_cur +* u00ad = pic_cur + offset + +L09d8 ldu $02,s get the pointer to the blit_struct + ldd $0C,u get the pointer to the view_data for mmu twiddler + lbsr L0074 twiddle mmu + + ldu $02,s get the pointer to the blit_struct data back in u + ldd $08,u load the x/y_size + std u00a1 stow that at x/y_count + clr u00a0 zero some adder + ldb $07,u get the y value + lda #$a0 set up PBUF_MULT + mul do the math + addb $06,u add in x + adca #0 add in the carry bit + addd #gfx_picbuff add in pic buff base $6040 + + ldu $0A,u load u with with the buffer pointer blit_cur +L09f5 std u00a8 save the buffer start pointer pic_cur + addd u00a0 add in the offset x_size + std u00ad stow that at pic_cur + offset + ldx u00a8 load x with pic_cur +L09fd ldd ,x++ copy 2 bytes at a time + std ,u++ to the buffer at blit_cur + cmpx u00ad have we copied it all ?? + blo L09fd nope loop again + + ldd u00a8 load with pic buffer start + addd #PICBUFF_WIDTH add 160 + dec u00a2 dec y_count + bne L09f5 not zero loop again + rts + + +* blit_restore(BLIT *b) obj_blit.c +* blit_save(BLIT *b) obj_blit.c +* our blit_struct is a bit different from the one in nagi +* +* u00a0 = zeroed and never changed cause we use the next byte :-) +* u00a1 = x_count (x_size) when cmpx ha ha +* u00a2 = y_count (y_size) +* u00a8 = pic buffer start pic_cur +* u00ad = pic_cur + offset + +L0a0f ldu $02,s get the pointer to the blit structure + ldd $0C,u + lbsr L0074 twiddle mmu + + ldu $02,s get the blit_structure back in u + ldd $08,u load x/y_size + std u00a1 stow them at x/y_count + clr u00a0 clear the byte prior to x_size + ldb $07,u get the y value + lda #$a0 set up PBUF_MULT + mul do the math + addb $06,u add in the x value + adca #0 add in the carry bit + addd #gfx_picbuff add in the base address $6040 + + ldu $0A,u load u with buffer pointer blit_cur +L0a2c std u00a8 save the screen start buffer pic_cur + addd u00a0 add in the x_size + std u00ad stow at pic_cur + offset + ldx u00a8 load x pic_cur pointer +L0a34 ldd ,u++ grab em from the buffer + std ,x++ and send them to the screen + cmpx u00ad moved them all ?? + blo L0a34 nope then keep on keeping on + + ldd u00a8 load the pic_cur pointer + addd #PICBUFF_WIDTH add 160 + dec u00a2 dec the y count + bne L0a2c not zero move some more + rts + + fcb $00,$00,$00,$00 + fcb $00,$00,$00,$00 + fcc "shdw" + fcb $00 + + emod + +eom equ * + + end \ No newline at end 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