diff options
Diffstat (limited to 'level_maps.txt')
| -rw-r--r-- | level_maps.txt | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/level_maps.txt b/level_maps.txt new file mode 100644 index 0000000..b114485 --- /dev/null +++ b/level_maps.txt @@ -0,0 +1,188 @@ +Level Maps +---------- + +level00_map: + .byte $FE,$33,$9C,$FD,$04,$00,$44,$05 ; A300 FE 33 9C FD 04 00 44 05 .3....D. + .byte $06,$04,$15,$0A,$74,$15,$0A,$24 ; A308 06 04 15 0A 74 15 0A 24 ....t..$ + .byte $22,$02,$74,$22,$02,$24,$25,$16 ; A310 22 02 74 22 02 24 25 16 ".t".$%. + .byte $04,$45,$04,$44,$45,$06,$8C,$45 ; A318 04 45 04 44 45 06 8C 45 .E.DE..E + .byte $04,$04,$55,$08,$34,$55,$0E,$7C ; A320 04 04 55 08 34 55 0E 7C ..U.4U.| + .byte $55,$08,$FD,$04,$FF,$34,$09,$04 ; A328 55 08 FD 04 FF 34 09 04 U....4.. + .byte $5C,$44,$0A,$FD,$04,$01,$5C,$06 ; A330 5C 44 0A FD 04 01 5C 06 \D....\. + .byte $04,$1C,$3B,$0A,$FE,$5F,$9C,$FD ; A338 04 1C 3B 0A FE 5F 9C FD ..;.._.. + .byte $00,$04,$0C,$41,$05,$8C,$41,$05 ; A340 00 04 0C 41 05 8C 41 05 ...A..A. + .byte $24,$01,$05,$74,$01,$05,$4C,$01 ; A348 24 01 05 74 01 05 4C 01 $..t..L. + .byte $15,$FE,$C9,$9C,$06,$18,$0A,$99 ; A350 15 FE C9 9C 06 18 0A 99 ........ + .byte $18,$0A,$FE,$DA,$9C,$1D,$38,$06 ; A358 18 0A FE DA 9C 1D 38 06 ......8. + .byte $81,$38,$06,$FE,$B3,$9C ; A360 81 38 06 FE B3 9C .8.... + +A300: FE 33 9C selects a shape (in this case, a girder) +A303: FD 04 00 sets the X and Y delta (4 pixels X, 0 lines Y) +A306: 44 is the X starting position +A307: 05 is the Y starting position +A308: 06 is the number of copies to draw (length of line) +A309: 04 is another X position (same shape type, still drawing girders) +A30A: 15 is another Y position (same shape type) +A30B: 0A is the number of copies to draw + +...more x/y/length tuples here, all drawn with dx=4, dy=0, aka +horizontally from left to right. + +A32A: $FD,$04,$FF sets a new X/Y delta. now we're drawing left and +down, for the diagonal girders (aka ramps) that run SW to NE. + +A333: $FD,$04,$01 is X/Y delta, drawing left and up, for the ramps +that run NW to SE (tilted the other way from the previous set). + +A33C: $FE,$5F,$9C selects a different shape (ladders) + +so eventually, I need ca65 macros that resemble instructions that assemble +into map data. Something like: + +set_gfx $9Cee +set_delta $04,$00 +draw_gfx $44,$05,$06 +draw_gfx $04,$15,$0A + +...notionally the drawing engine is a little CPU with 3 16-bit registers: +a program counter (stored at $C0), gfx (the graphic object it draws) +and delta (2 8-bit signed ints). It has 5 opcodes: + +$FC - gfx_jump (operand = 16-bit target address) +$FD - gfx_delta (operand = 2 8-bit signed ints) +$FE - gfx_shape (operand = 16-bit address of shape, see below) +$FF - gfx_end (done drawing) +Anything else - gfx_draw (opcode is X start, next 2 bytes are Y and length) + +All the opcodes other than gfx_end are 3 bytes. Write macros for ca65 and a +disassembler in perl. + +There are 13 primary maps (one per level, plus the WELL DONE screen). Some +(all?) levels also have secondary map data, which I think is used for +changing parts of the map during the level (e.g. the disappearing girders +on level 1). + +Shapes +------ + +Actual graphics data (girder sections, ladders, etc) is stored less +efficiently. I'm not going to call these "sprites" because they don't +move, and I'm not going to call them "tiles" because they aren't (they +can be placed at arbitrary X/Y positions, not limited to a character +map style grid). So I'll refer them as a "shape". + +Each shape is at least one pixel wide and at least 1 pixel tall. Pixels +are 2 bits wide (4-color GR.7 mode), and are stored unpacked (2 bits +per byte). + +Here's what the girder section looks like: + +girder: .byte $04,$00,$00,$01,$01,$01,$01,$04 ; 9C33 04 00 00 01 01 01 01 04 ........ + .byte $00,$01,$01,$00,$01,$00,$04,$00 ; 9C3B 00 01 01 00 01 00 04 00 ........ + .byte $02,$01,$01,$01,$01,$FF,$xx,$xx ; 9C43 02 01 01 01 01 FF xx xx ........ + +That's from the disassembly, the xx's are "don't care" because they're +actually part of the next shape in the table. + +Here's the same thing, laid out in a more human-readable way [*] + +girder: +girder_row0: +girder_row0_width: .byte $04 +girder_row0_x_offset: .byte $00 +girder_row0_y_offset: .byte $00 +girder_row0_pixels: .byte $01,$01,$01,$01 +girder_row1: +girder_row1_width: .byte $04 +girder_row1_x_offset: .byte $00 +girder_row1_y_offset: .byte $01 +girder_row1_pixels: .byte $01,$00,$01,$00 +girder_row2: +girder_row2_width: .byte $04 +girder_row2_x_offset: .byte $00 +girder_row2_y_offset: .byte $02 +girder_row2_pixels: .byte $01,$01,$01,$01 +girder_end: .byte $FF + + [*] Getting da65 to emit this would be possible but unwieldy, it'll have + to wait until I've mapped out all the 'unknown' code/data sections + and can start manually editing the disassembly to turn it into + proper source. + +This makes a shape like this: + +XXXX +X X +XXXX + +...which you'll recognize as a girder segment, if you squint a little. + +Notice the use of $FF as an end marker. If it occurs in place of a width, +the dm_draw_gfx routine knows it's done, and exits immediately. + +Here's the next shape in the table: + +blank: +blank_row0: +blank_row0_width: .byte $04 +blank_row0_x_offset: .byte $00 +blank_row0_y_offset: .byte $00 +blank_row0_pixels: .byte $00,$00,$00,$00 +blank_row1: +blank_row1_width: .byte $04 +blank_row1_x_offset: .byte $00 +blank_row1_y_offset: .byte $01 +blank_row1_pixels: .byte $00,$00,$00,$00 +blank_row2: +blank_row2_width: .byte $04 +blank_row2_x_offset: .byte $00 +blank_row2_y_offset: .byte $02 +blank_row2_pixels: .byte $00,$00,$00,$00 +blank_end: .byte $FF + +This is a 4x4 block of empty pixels. It's probably used to erase parts +of the level (e.g. the disappearing platforms on level 1). + +Next: + +xxx: +xxx_row0: +xxx_row0_width: .byte $02 +xxx_row0_x_offset: .byte $00 +xxx_row0_y_offset: .byte $00 +xxx_row0_pixels: .byte $02,$02 + +xxx_row1_width: .byte $02 +xxx_row1_x_offset: .byte $06 +xxx_row1_y_offset: .byte $00 +xxx_row1_pixels: .byte $02,$02 + +xxx_row2_width: .byte $02 +xxx_row2_x_offset: .byte $00 +xxx_row2_y_offset: .byte $01 +xxx_row2_pixels: .byte $02,$02 + +xxx_row3_width: .byte $02 +xxx_row3_x_offset: .byte $06 +xxx_row3_y_offset: .byte $01 +xxx_row3_pixels: .byte $02,$02 + +xxx_row4_width: .byte $08 +xxx_row4_x_offset: .byte $00 +xxx_row4_y_offset: .byte $02 +xxx_row4_pixels: .byte $02,$02,$02,$02,$02,$02,$02,$02 + +xxx_row5_width: .byte $02 +xxx_row5_x_offset: .byte $00 +xxx_row5_y_offset: .byte $03 +xxx_row5_pixels: .byte $02,$02 + +xxx_row6_width: .byte $02 +xxx_row6_x_offset: .byte $06 +xxx_row6_y_offset: .byte $03 +xxx_row6_pixels: .byte $02,$02 + +xxx_end: .byte $FF + +In this one, all the pixels are $02. Most of the shapes will be like +this, only using one color. |