1263 lines
23 KiB
NASM
1263 lines
23 KiB
NASM
; -----------------------------------------------------------
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; play.asm - the game: a fresh maze carves itself on screen
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; every round (recursive backtracker, a few steps a frame),
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; player 1 (joystick 2) runs the corridors toward the exit
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; portal, player 2 (joystick 1) rides the wall corners and
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; fire spins the four wall pieces around the cursor by 90
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; degrees; the roaming enemies end the round on touch
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;
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; the walls, posts and the portal are chars (the screen stays
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; the wall data structure), but every actor - runner, cursor,
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; bullet, enemies - is a hardware sprite gliding between the
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; cells; actor collisions are grid coordinate checks
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;
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; optional extras (see options.asm):
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; opt_shoot - player 1's fire shoots a bullet in the last
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; direction faced; a hit enemy respawns on a
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; random cell after RESPAWN_TIME frames
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; opt_cool - a spin starts a COOL_TIME recharge, shown as
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; a draining 1/8-step bar on the status row
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;
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; screen layout: status on row 0 (over the colored raster
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; band), the 39x23 maze lattice on rows 1-23, hints on row 24
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; -----------------------------------------------------------
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play_init:
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jsr clear_screen
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+prtext 0, 0, WHITE, txt_t1, 7
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+prtext 0, 7, CYAN, txt_t2, 3
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+prtext 0, 28, LGREY, txt_goal, txt_goale-txt_goal
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+prtext 24, 6, DGREY, txt_hint, txt_hinte-txt_hint
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lda #COL_WALL
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sta latwcol
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lda #COL_POST
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sta latpcol
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jsr draw_lattice
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jsr gen_init
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lda #0 ; the actors arrive when the maze is done
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sta SPR_EN
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lda #STATCOL ; the status row gets its color band
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sta statbg
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+setupd play_build
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rts
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; ---- the maze carves itself, BUILD_STEPS steps a frame ----
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play_build:
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lda #BUILD_STEPS
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sta ptmp
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pb_loop:
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jsr gm_step
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bcs play_start
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dec ptmp
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bne pb_loop
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rts
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; ---- the maze is done: exit, actors, sprites, input ----
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play_start:
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; the exit: a portal in the right border wall
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ps_exit:
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jsr rand8
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and #$0f
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cmp #MAZE_CH
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bcs ps_exit
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asl ; cell row -> screen row
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clc
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adc #2
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sta exrow
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tax
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jsr row_ptr
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ldy #38
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lda #CH_EXIT
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sta (scrlo),y
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lda #COL_EXIT
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sta (collo),y
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; the runner starts in the top-left cell, facing right
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lda #1
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sta px
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sta fdx
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lda #2
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sta py
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lda #0
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sta fdy
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lda px
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sta tgc
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lda py
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sta tgr
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jsr set_target
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ldx #SP_RUN
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jsr spr_jump
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; the corner cursor starts on the center post
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lda #18
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sta kx
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lda #11
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sta ky
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lda #COL_HILITE
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jsr mark_slots
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lda kx
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sta tgc
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lda ky
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sta tgr
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jsr set_target
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ldx #SP_CUR
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jsr spr_jump
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lda #WHITE
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sta SPRCOL+SP_RUN
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sta SPRCOL+SP_CUR
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lda #YELLOW
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sta SPRCOL+SP_SHOT
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jsr spawn_enemies
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; input state: fire still held from the previous screen
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; must be released before it can spin or shoot
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lda #0
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sta rheld
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sta cheld
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sta endflag
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sta s_on
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sta sx
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sta sy
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sta cool
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sta rotflash
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lda #1
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sta cfheld
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sta rfheld
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+setupd play_update
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jmp upd_sprites ; positions, shapes and enables now
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; ============================================================
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; maze generation - recursive backtracker over the 19x11
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; cells; the screen itself is the wall data structure
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; ============================================================
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; fill rows 1-23 of the lattice: brick walls in latwcol, the
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; pivot posts (even col, odd row) in latpcol
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draw_lattice:
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ldx #1
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dl_fill:
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stx ptmp
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jsr row_ptr
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ldy #38
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dl_col:
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lda #CH_WALL
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sta (scrlo),y
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lda latwcol
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sta (collo),y
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dey
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bpl dl_col
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ldx ptmp
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inx
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cpx #24
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bne dl_fill
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ldx #1 ; post rows 1, 3, ... 23
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dl_prow:
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stx ptmp
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jsr row_ptr
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ldy #38 ; post columns 38, 36, ... 0
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dl_pcol:
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lda #CH_POST
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sta (scrlo),y
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lda latpcol
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sta (collo),y
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dey
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dey
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bpl dl_pcol
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ldx ptmp
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inx
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inx
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cpx #25
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bcc dl_prow
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rts
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; reset the generator: nothing visited, start on cell (0,0)
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gen_init:
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ldx #0
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lda #0
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gi_clr:
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sta visited,x
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inx
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cpx #NCELLS
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bne gi_clr
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lda #0
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sta gcx
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sta gcy
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sta gsp
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jsr gv_mark
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jmp carve_cell
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; one generator step: carve toward a random unvisited
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; neighbor, or back up one; C set when the maze is finished
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gm_step:
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; collect the unvisited neighbor directions
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lda #0
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sta gn
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ldx #0
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gm_scan:
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stx gtd
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lda gcx
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clc
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adc dxtab,x
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sta gnx
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cmp #MAZE_CW ; unsigned: -1 wraps to $ff and fails too
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bcs gm_next
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ldx gtd
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lda gcy
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clc
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adc dytab,x
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sta gny
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cmp #MAZE_CH
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bcs gm_next
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ldx gny
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lda mul19,x
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clc
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adc gnx
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tax
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lda visited,x
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bne gm_next
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ldx gn
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lda gtd
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sta gdlist,x
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inc gn
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gm_next:
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ldx gtd
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inx
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cpx #4
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bne gm_scan
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lda gn
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beq gm_pop
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; pick a random one of them
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gm_pick:
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jsr rand8
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and #3
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cmp gn
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bcs gm_pick
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tax
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lda gdlist,x
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sta gtd
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; push the current cell, open the wall, step through it
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ldx gsp
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lda gcx
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sta stackx,x
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lda gcy
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sta stacky,x
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inc gsp
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jsr carve_wall
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ldx gtd
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lda gcx
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clc
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adc dxtab,x
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sta gcx
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ldx gtd
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lda gcy
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clc
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adc dytab,x
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sta gcy
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jsr gv_mark
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jsr carve_cell
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clc
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rts
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gm_pop:
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; dead end: back up; empty stack = the maze is done
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lda gsp
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beq gm_done
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dec gsp
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ldx gsp
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lda stackx,x
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sta gcx
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lda stacky,x
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sta gcy
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clc
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rts
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gm_done:
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sec
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rts
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gen_maze_full: ; the menu backdrop wants it all at once
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jsr gm_step
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bcc gen_maze_full
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rts
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gv_mark: ; visited[gcy * 19 + gcx] = 1
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ldx gcy
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lda mul19,x
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clc
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adc gcx
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tax
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lda #1
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sta visited,x
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rts
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carve_cell: ; open the cell (2*gcx+1, 2*gcy+2)
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lda gcy
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asl
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clc
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adc #2
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tax
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jsr row_ptr
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lda gcx
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asl
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clc
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adc #1
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tay
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lda #CH_FLOOR
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sta (scrlo),y
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lda #BLACK
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sta (collo),y
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rts
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carve_wall: ; open the wall slot toward direction gtd
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ldx gtd
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lda gcy
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asl
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clc
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adc #2
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clc
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adc dytab,x
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tax
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jsr row_ptr
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ldx gtd
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lda gcx
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asl
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clc
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adc #1
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clc
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adc dxtab,x
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tay
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lda #CH_FLOOR
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sta (scrlo),y
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lda #BLACK
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sta (collo),y
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rts
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dxtab: !byte 0, 0, $ff, 1 ; up, down, left, right
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dytab: !byte $ff, 1, 0, 0
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mul19: !byte 0, 19, 38, 57, 76, 95, 114, 133, 152, 171, 190
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; ---- enemies: random colors, random right-half cells ----
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spawn_enemies:
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lda #0
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sta ei
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sn_all:
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jsr spawn_one
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inc ei
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lda ei
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cmp #NENEMIES
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bne sn_all
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rts
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spawn_one: ; place enemy ei on a random free cell
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sn_rx:
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jsr rand8
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and #$0f
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cmp #MAZE_CH
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bcs sn_rx
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clc
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adc #MAZE_CW-MAZE_CH ; cell column 8-18: away from the start
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asl
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clc
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adc #1
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sta ttx ; candidate screen column
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sn_ry:
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jsr rand8
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and #$0f
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cmp #MAZE_CH
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bcs sn_ry
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asl
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clc
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adc #2
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sta tty ; candidate screen row
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ldx tty
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jsr row_ptr
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ldy ttx
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lda (scrlo),y
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cmp #CH_FLOOR ; only a carved cell will do...
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bne sn_rx
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lda ttx ; ...without the runner on it...
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cmp px
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bne sn_free
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lda tty
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cmp py
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beq sn_rx
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sn_free:
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jsr enemy_at ; ...or another live enemy
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bcs sn_rx
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ldx ei
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lda ttx
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sta ex,x
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lda tty
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sta ey,x
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jsr rand8
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and #7
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tay
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lda ecoltab,y
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sta ecol,x
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sta SPRCOL+SP_EN,x
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jsr rand8
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and #3
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sta edir,x
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lda #0
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sta edead,x
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lda ttx ; the sprite pops in on the cell
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sta tgc
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lda tty
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sta tgr
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jsr set_target
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lda ei
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clc
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adc #SP_EN
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tax
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jmp spr_jump
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ecoltab: ; anything but the white runner / grey walls
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!byte RED, CYAN, PURPLE, YELLOW, ORANGE, LRED, LBLUE, BLUE
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; ============================================================
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; one frame of play
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; ============================================================
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play_update:
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lda cool ; the spin recharge ticks down
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beq pu_nocool
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dec cool
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pu_nocool:
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jsr upd_runner
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lda endflag
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bne pu_end
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jsr upd_shot
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jsr upd_enemies
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lda endflag
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bne pu_end
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jsr upd_cursor
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jsr upd_flash
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jsr upd_status
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jmp upd_sprites
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pu_end:
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cmp #1
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beq pu_win
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lda #SFX_LOSE
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jsr sfx_play
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+fadeto lose_init
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pu_win:
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lda #SFX_WIN
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jsr sfx_play
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+fadeto win_init
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; ---- player 1: walk the corridors, one cell per step ----
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upd_runner:
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jsr read_joy
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and #$0f
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sta rdir
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bne ur_held
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lda #0
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sta rheld
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rts
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ur_held:
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lda rheld
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beq ur_first
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dec rtimer
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beq ur_rep
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rts
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ur_rep:
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lda #REP_PERIOD
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sta rtimer
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jmp ur_move
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ur_first:
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lda #1
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sta rheld
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lda #REP_HOLD
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sta rtimer
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ur_move:
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; decode the direction; it also becomes the gun's facing
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ldx px
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ldy py
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lda rdir
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lsr
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bcs ur_up
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lsr
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bcs ur_down
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lsr
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bcs ur_left
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inx ; right
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lda #1
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sta fdx
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lda #0
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sta fdy
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jmp ur_try
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ur_up:
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dey
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lda #0
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sta fdx
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lda #$ff
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sta fdy
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jmp ur_try
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ur_down:
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iny
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lda #0
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sta fdx
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lda #1
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sta fdy
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jmp ur_try
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ur_left:
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dex
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lda #$ff
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sta fdx
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lda #0
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sta fdy
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ur_try:
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stx ttx
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sty tty
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ldx tty
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jsr row_ptr
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ldy ttx
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lda (scrlo),y
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cmp #CH_EXIT
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beq ur_win
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cmp #CH_FLOOR
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bne ur_stop ; a wall or a post: blocked
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jsr enemy_at ; walking into an enemy still hurts
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bcs ur_dead
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lda ttx
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sta px
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lda tty
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sta py
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ur_stop:
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rts
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ur_win:
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lda #1
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sta endflag
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rts
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ur_dead:
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lda #2
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sta endflag
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rts
|
|
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; ---- the optional gun: one straight-flying bullet sprite ----
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upd_shot:
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lda s_on
|
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beq sh_spawn
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lda sx ; one step along its heading
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clc
|
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adc sdx
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sta ttx
|
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lda sy
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clc
|
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adc sdy
|
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sta tty
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ldx tty
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jsr row_ptr
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ldy ttx
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lda (scrlo),y
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cmp #CH_FLOOR
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beq sh_open
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lda #0 ; a wall (or the portal) stops it
|
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sta s_on
|
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jmp sh_spawn
|
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sh_open:
|
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jsr enemy_at
|
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bcc sh_fly
|
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jsr kill_idx ; X = the victim
|
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lda #0
|
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sta s_on
|
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jmp sh_spawn
|
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sh_fly:
|
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lda ttx
|
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sta sx
|
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lda tty
|
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sta sy
|
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sh_spawn:
|
|
lda opt_shoot ; fire spawns a bullet (edge detected)
|
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beq sh_done
|
|
lda joyb ; read_joy ran in upd_runner this frame
|
|
and #JOY_FIRE
|
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beq sh_frel
|
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lda rfheld
|
|
bne sh_done
|
|
lda #1
|
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sta rfheld
|
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lda s_on
|
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bne sh_done ; one bullet at a time
|
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lda px
|
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sta sx
|
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lda py
|
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sta sy
|
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lda fdx
|
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sta sdx
|
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lda fdy
|
|
sta sdy
|
|
lda #1
|
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sta s_on
|
|
lda #SFX_SHOT
|
|
jmp sfx_play
|
|
sh_frel:
|
|
lda #0
|
|
sta rfheld
|
|
sh_done:
|
|
rts
|
|
|
|
; ---- enemy X was hit: it starts its respawn timer ----
|
|
kill_idx:
|
|
lda #RESPAWN_TIME
|
|
sta edead,x
|
|
lda #4 ; white border blip
|
|
sta bflash
|
|
lda #WHITE
|
|
sta bcolor
|
|
lda #SFX_HIT
|
|
jmp sfx_play
|
|
|
|
; ---- is a live enemy standing on (ttx, tty)?
|
|
; returns C set + its index in X when one is ----
|
|
enemy_at:
|
|
ldx #0
|
|
ea_loop:
|
|
lda edead,x
|
|
bne ea_next
|
|
lda ex,x
|
|
cmp ttx
|
|
bne ea_next
|
|
lda ey,x
|
|
cmp tty
|
|
bne ea_next
|
|
sec
|
|
rts
|
|
ea_next:
|
|
inx
|
|
cpx #NENEMIES
|
|
bne ea_loop
|
|
clc
|
|
rts
|
|
|
|
; ---- player 2: the corner cursor + the wall spin ----
|
|
upd_cursor:
|
|
jsr read_joy2
|
|
sta j2bits
|
|
and #$0f
|
|
sta cdir
|
|
bne uc_held
|
|
lda #0
|
|
sta cheld
|
|
jmp uc_fire
|
|
uc_held:
|
|
lda cheld
|
|
beq uc_first
|
|
dec ctimer
|
|
beq uc_rep
|
|
jmp uc_fire
|
|
uc_rep:
|
|
lda #CREP_PERIOD
|
|
sta ctimer
|
|
jmp uc_move
|
|
uc_first:
|
|
lda #1
|
|
sta cheld
|
|
lda #CREP_HOLD
|
|
sta ctimer
|
|
uc_move:
|
|
ldx kx
|
|
ldy ky
|
|
lda cdir
|
|
lsr
|
|
bcs uc_up
|
|
lsr
|
|
bcs uc_down
|
|
lsr
|
|
bcs uc_left
|
|
cpx #36 ; right: interior posts end at column 36
|
|
bcs uc_fire
|
|
inx
|
|
inx
|
|
jmp uc_go
|
|
uc_up:
|
|
cpy #4 ; top interior post row is 3
|
|
bcc uc_fire
|
|
dey
|
|
dey
|
|
jmp uc_go
|
|
uc_down:
|
|
cpy #21 ; bottom interior post row is 21
|
|
bcs uc_fire
|
|
iny
|
|
iny
|
|
jmp uc_go
|
|
uc_left:
|
|
cpx #3 ; left interior post column is 2
|
|
bcc uc_fire
|
|
dex
|
|
dex
|
|
uc_go:
|
|
stx ttx
|
|
sty tty
|
|
lda #COL_WALL ; the old corner's walls lose the highlight
|
|
jsr mark_slots
|
|
lda #0 ; a spin flash does not follow the cursor
|
|
sta rotflash
|
|
lda ttx
|
|
sta kx
|
|
lda tty
|
|
sta ky
|
|
lda #COL_HILITE ; show the walls a spin here would move
|
|
jsr mark_slots
|
|
lda #SFX_CURSOR
|
|
jsr sfx_play
|
|
uc_fire:
|
|
lda j2bits
|
|
and #JOY_FIRE
|
|
beq uc_frel
|
|
lda cfheld
|
|
bne uc_done
|
|
lda #1
|
|
sta cfheld
|
|
jmp do_rotate ; its rts returns to play_update's caller
|
|
uc_frel:
|
|
lda #0
|
|
sta cfheld
|
|
uc_done:
|
|
rts
|
|
|
|
; ---- spin the four wall slots around post (kx, ky) by 90
|
|
; degrees clockwise; denied while anyone stands in them or
|
|
; while the optional cooldown is still recharging ----
|
|
do_rotate:
|
|
lda opt_cool
|
|
beq dr_ready
|
|
lda cool
|
|
beq dr_ready
|
|
dr_deny:
|
|
jmp rot_deny ; still recharging / a slot is taken
|
|
dr_ready:
|
|
lda kx ; nobody may stand in the four slots
|
|
sta ttx
|
|
ldx ky
|
|
dex
|
|
stx tty
|
|
jsr slot_occ
|
|
bcs dr_deny
|
|
ldx ky
|
|
inx
|
|
stx tty
|
|
jsr slot_occ
|
|
bcs dr_deny
|
|
lda ky
|
|
sta tty
|
|
ldx kx
|
|
dex
|
|
stx ttx
|
|
jsr slot_occ
|
|
bcs dr_deny
|
|
ldx kx
|
|
inx
|
|
stx ttx
|
|
jsr slot_occ
|
|
bcs dr_deny
|
|
ldx ky ; gather the four slot chars
|
|
dex
|
|
jsr row_ptr
|
|
ldy kx
|
|
lda (scrlo),y
|
|
sta nch
|
|
ldx ky
|
|
inx
|
|
jsr row_ptr
|
|
ldy kx
|
|
lda (scrlo),y
|
|
sta sch
|
|
ldx ky
|
|
jsr row_ptr
|
|
ldy kx
|
|
dey
|
|
lda (scrlo),y
|
|
sta wch
|
|
iny
|
|
iny
|
|
lda (scrlo),y
|
|
sta ech
|
|
; clockwise: north<-west, east<-north, south<-east, west<-south
|
|
ldx ky
|
|
dex
|
|
jsr row_ptr
|
|
ldy kx
|
|
lda wch
|
|
jsr put_slot
|
|
ldx ky
|
|
inx
|
|
jsr row_ptr
|
|
ldy kx
|
|
lda ech
|
|
jsr put_slot
|
|
ldx ky
|
|
jsr row_ptr
|
|
ldy kx
|
|
dey
|
|
lda sch
|
|
jsr put_slot
|
|
iny
|
|
iny
|
|
lda nch
|
|
jsr put_slot
|
|
lda #10 ; the moved pieces flash white
|
|
sta rotflash
|
|
lda opt_cool ; the spin starts the recharge
|
|
beq dr_nocool
|
|
lda #COOL_TIME
|
|
sta cool
|
|
dr_nocool:
|
|
lda #SFX_ROTATE
|
|
jmp sfx_play
|
|
rot_deny:
|
|
lda #6 ; red border blip on a denied spin
|
|
sta bflash
|
|
lda #RED
|
|
sta bcolor
|
|
lda #SFX_DENY
|
|
jmp sfx_play
|
|
|
|
slot_occ: ; C set when someone stands on (ttx, tty)
|
|
lda px
|
|
cmp ttx
|
|
bne so_norun
|
|
lda py
|
|
cmp tty
|
|
beq so_yes
|
|
so_norun:
|
|
jsr enemy_at
|
|
bcs so_yes
|
|
lda s_on
|
|
beq so_no
|
|
lda sx
|
|
cmp ttx
|
|
bne so_no
|
|
lda sy
|
|
cmp tty
|
|
beq so_yes
|
|
so_no:
|
|
clc
|
|
rts
|
|
so_yes:
|
|
sec
|
|
rts
|
|
|
|
put_slot: ; write char A at (scrlo),y + matching color
|
|
sta (scrlo),y
|
|
cmp #CH_WALL
|
|
beq ps_wall
|
|
lda #BLACK
|
|
sta (collo),y
|
|
rts
|
|
ps_wall:
|
|
lda #COL_WALL
|
|
sta (collo),y
|
|
rts
|
|
|
|
; ---- paint the four slots around the cursor post with the
|
|
; color in A - only wall blocks change, so the highlight marks
|
|
; exactly the pieces a spin would move (floors stay black) ----
|
|
mark_slots:
|
|
sta hlcol
|
|
ldx ky ; north
|
|
dex
|
|
jsr row_ptr
|
|
ldy kx
|
|
jsr mark_one
|
|
ldx ky ; south
|
|
inx
|
|
jsr row_ptr
|
|
ldy kx
|
|
jsr mark_one
|
|
ldx ky ; west
|
|
jsr row_ptr
|
|
ldy kx
|
|
dey
|
|
jsr mark_one
|
|
iny ; east: falls through to mark it
|
|
iny
|
|
mark_one:
|
|
lda (scrlo),y
|
|
cmp #CH_WALL
|
|
bne mo_skip
|
|
lda hlcol
|
|
sta (collo),y
|
|
mo_skip:
|
|
rts
|
|
|
|
; ---- the enemies: staggered random walkers ----
|
|
upd_enemies:
|
|
lda #0
|
|
sta ei
|
|
ue_loop:
|
|
ldx ei
|
|
lda edead,x
|
|
beq ue_alive
|
|
dec edead,x ; shot down: waiting to respawn
|
|
bne ue_next
|
|
jsr spawn_one ; the timer ran out: back on a fresh cell
|
|
jmp ue_next
|
|
ue_alive:
|
|
lda framectr
|
|
clc
|
|
adc estag,x
|
|
and #7 ; each enemy steps every 8th frame
|
|
bne ue_next
|
|
jsr enemy_step
|
|
lda endflag
|
|
bne ue_out
|
|
ue_next:
|
|
inc ei
|
|
lda ei
|
|
cmp #NENEMIES
|
|
bne ue_loop
|
|
ue_out:
|
|
rts
|
|
|
|
estag: !byte 0, 2, 4, 6
|
|
|
|
enemy_step:
|
|
jsr rand8 ; 1 in 4: wander off in a new direction
|
|
and #3
|
|
beq es_newdir
|
|
ldx ei
|
|
lda edir,x
|
|
jsr etry_dir
|
|
bcc es_done
|
|
es_newdir:
|
|
lda #8
|
|
sta etries
|
|
es_pick:
|
|
jsr rand8
|
|
and #3
|
|
jsr etry_dir
|
|
bcc es_done
|
|
dec etries ; walled in on all sides: sit this one out
|
|
bne es_pick
|
|
es_done:
|
|
rts
|
|
|
|
etry_dir: ; A = direction; C clear when it moved (or won)
|
|
sta etd
|
|
tax
|
|
ldy ei
|
|
lda ex,y
|
|
clc
|
|
adc dxtab,x
|
|
sta ttx
|
|
lda ey,y
|
|
clc
|
|
adc dytab,x
|
|
sta tty
|
|
lda px ; onto the runner: the round is over
|
|
cmp ttx
|
|
bne en_norun
|
|
lda py
|
|
cmp tty
|
|
bne en_norun
|
|
lda #2
|
|
sta endflag
|
|
clc
|
|
rts
|
|
en_norun:
|
|
ldx tty ; anything but open floor blocks it
|
|
jsr row_ptr
|
|
ldy ttx
|
|
lda (scrlo),y
|
|
cmp #CH_FLOOR
|
|
beq en_open
|
|
sec
|
|
rts
|
|
en_open:
|
|
jsr enemy_at ; another enemy blocks it
|
|
bcc en_nofoe
|
|
sec
|
|
rts
|
|
en_nofoe:
|
|
lda s_on ; walking into the bullet hurts too
|
|
beq en_move
|
|
lda sx
|
|
cmp ttx
|
|
bne en_move
|
|
lda sy
|
|
cmp tty
|
|
bne en_move
|
|
lda #0
|
|
sta s_on
|
|
ldx ei
|
|
jsr kill_idx
|
|
clc
|
|
rts
|
|
en_move:
|
|
ldx ei
|
|
lda ttx
|
|
sta ex,x
|
|
lda tty
|
|
sta ey,x
|
|
lda etd
|
|
sta edir,x
|
|
clc
|
|
rts
|
|
|
|
; ---- per-frame flashes: the portal spins and blinks, the
|
|
; freshly spun walls flash white, the cursor shows the
|
|
; recharge state on its own color ----
|
|
upd_flash:
|
|
jsr upd_portal ; cycle the portal glyph
|
|
ldx exrow
|
|
jsr row_ptr
|
|
ldy #38
|
|
lda framectr
|
|
and #8
|
|
bne uf_exw
|
|
lda #COL_EXIT
|
|
jmp uf_exset
|
|
uf_exw:
|
|
lda #WHITE
|
|
uf_exset:
|
|
sta (collo),y
|
|
lda rotflash ; the spun walls flash, then re-highlight
|
|
beq uf_norf
|
|
dec rotflash
|
|
bne uf_white
|
|
lda #COL_HILITE
|
|
jmp uf_mark
|
|
uf_white:
|
|
lda #WHITE
|
|
uf_mark:
|
|
jsr mark_slots
|
|
uf_norf:
|
|
lda opt_cool ; the cursor dims red while recharging
|
|
beq uf_hot
|
|
lda cool
|
|
beq uf_hot
|
|
lda #RED
|
|
jmp uf_cset
|
|
uf_hot:
|
|
lda #WHITE
|
|
uf_cset:
|
|
sta SPRCOL+SP_CUR
|
|
rts
|
|
|
|
; ---- status row: the spin recharge readout (cooldown option)
|
|
; "wait" + a bar draining pixel by pixel, "ready" after ----
|
|
upd_status:
|
|
lda opt_cool
|
|
bne us_show
|
|
rts
|
|
us_show:
|
|
lda cool
|
|
beq us_ready
|
|
+prtext 0, 12, LRED, txt_wait, 4
|
|
lda cool ; pixels left: cool / 2 = 0-80
|
|
lsr
|
|
sta ptmp
|
|
ldx #0
|
|
us_bar:
|
|
lda ptmp
|
|
beq us_empty
|
|
cmp #8
|
|
bcc us_part
|
|
sec ; a full cell, and onward
|
|
sbc #8
|
|
sta ptmp
|
|
lda #$a0
|
|
jmp us_put
|
|
us_part:
|
|
clc ; 1-7 pixels: one of the bar chars
|
|
adc #CH_BAR-1
|
|
ldy #0
|
|
sty ptmp
|
|
jmp us_put
|
|
us_empty:
|
|
lda #$20
|
|
us_put:
|
|
sta SCREEN+18,x ; bar cells: row 0, columns 18-27
|
|
lda #LRED
|
|
sta COLRAM+18,x
|
|
inx
|
|
cpx #10
|
|
bne us_bar
|
|
rts
|
|
us_ready:
|
|
+prtext 0, 12, LGREEN, txt_ready, 5
|
|
lda #$20 ; clear the bar area
|
|
ldx #9
|
|
us_clr:
|
|
sta SCREEN+18,x
|
|
dex
|
|
bpl us_clr
|
|
rts
|
|
|
|
; ---- drive the eight sprites from the grid state ----
|
|
upd_sprites:
|
|
lda framectr
|
|
lsr
|
|
lsr
|
|
lsr
|
|
sta frame8
|
|
; the runner glides 2 pixels a frame
|
|
lda px
|
|
sta tgc
|
|
lda py
|
|
sta tgr
|
|
jsr set_target
|
|
lda #2
|
|
sta gspd
|
|
ldx #SP_RUN
|
|
jsr spr_glide
|
|
; the cursor glides 4 (its step is two cells)
|
|
lda kx
|
|
sta tgc
|
|
lda ky
|
|
sta tgr
|
|
jsr set_target
|
|
lda #4
|
|
sta gspd
|
|
ldx #SP_CUR
|
|
jsr spr_glide
|
|
; the bullet snaps cell to cell
|
|
lda sx
|
|
sta tgc
|
|
lda sy
|
|
sta tgr
|
|
jsr set_target
|
|
ldx #SP_SHOT
|
|
jsr spr_jump
|
|
; the enemies glide 1
|
|
lda #1
|
|
sta gspd
|
|
ldx #0
|
|
us_en:
|
|
stx ptmp
|
|
lda ex,x
|
|
sta tgc
|
|
lda ey,x
|
|
sta tgr
|
|
jsr set_target
|
|
lda ptmp
|
|
clc
|
|
adc #SP_EN
|
|
tax
|
|
jsr spr_glide
|
|
ldx ptmp
|
|
inx
|
|
cpx #NENEMIES
|
|
bne us_en
|
|
; shapes: the runner bobs, each enemy waves on its own beat
|
|
lda frame8
|
|
and #1
|
|
clc
|
|
adc #SPR_RUN
|
|
sta SPRPTR+SP_RUN
|
|
lda #SPR_CUR
|
|
sta SPRPTR+SP_CUR
|
|
lda #SPR_SHOT
|
|
sta SPRPTR+SP_SHOT
|
|
ldx #0
|
|
us_shape:
|
|
txa
|
|
clc
|
|
adc frame8
|
|
and #1
|
|
sta rtmp
|
|
lda #SPR_ENA ; enemies 0-1 are ghosts, 2-3 crawlers
|
|
cpx #2
|
|
bcc us_seta
|
|
lda #SPR_ENB
|
|
us_seta:
|
|
clc
|
|
adc rtmp
|
|
sta SPRPTR+SP_EN,x
|
|
inx
|
|
cpx #NENEMIES
|
|
bne us_shape
|
|
; enable: runner + cursor + the bullet and the live enemies
|
|
lda #%00000011
|
|
ldy s_on
|
|
beq us_nosht
|
|
ora #%00000100
|
|
us_nosht:
|
|
sta rtmp
|
|
ldx #0
|
|
us_alive:
|
|
lda edead,x
|
|
bne us_dead
|
|
lda rtmp
|
|
ora ebit,x
|
|
sta rtmp
|
|
us_dead:
|
|
inx
|
|
cpx #NENEMIES
|
|
bne us_alive
|
|
lda rtmp
|
|
sta SPR_EN
|
|
jmp spr_commit
|
|
|
|
ebit: !byte 8, 16, 32, 64
|
|
|
|
; ---- play texts ----
|
|
txt_goal: !scr "reach the "
|
|
!byte CH_EXIT
|
|
txt_goale:
|
|
txt_hint: !scr "p1: joy2/wasd p2: joy1/ijkl"
|
|
txt_hinte:
|
|
txt_wait: !scr "wait"
|
|
txt_ready: !scr "ready"
|
|
|
|
; ---- play variables ----
|
|
px: !byte 0 ; runner position (screen col / row)
|
|
py: !byte 0
|
|
fdx: !byte 0 ; runner facing: the gun aims this way
|
|
fdy: !byte 0
|
|
kx: !byte 0 ; corner cursor position (post col / row)
|
|
ky: !byte 0
|
|
exrow: !byte 0 ; screen row of the exit portal
|
|
endflag: !byte 0 ; 0 = playing, 1 = escaped, 2 = caught
|
|
cool: !byte 0 ; spin recharge frames left (cooldown option)
|
|
rotflash:!byte 0 ; frames the freshly spun walls stay white
|
|
s_on: !byte 0 ; bullet in flight?
|
|
sx: !byte 0 ; bullet position and heading
|
|
sy: !byte 0
|
|
sdx: !byte 0
|
|
sdy: !byte 0
|
|
rheld: !byte 0 ; runner direction repeat state
|
|
rtimer: !byte 0
|
|
rdir: !byte 0
|
|
rfheld: !byte 0 ; runner fire edge detection state
|
|
cheld: !byte 0 ; cursor direction repeat state
|
|
ctimer: !byte 0
|
|
cdir: !byte 0
|
|
cfheld: !byte 0 ; cursor fire edge detection state
|
|
j2bits: !byte 0
|
|
ptmp: !byte 0 ; scratch
|
|
ttx: !byte 0 ; move target (col / row)
|
|
tty: !byte 0
|
|
nch: !byte 0 ; the four slot chars around the cursor
|
|
ech: !byte 0
|
|
sch: !byte 0
|
|
wch: !byte 0
|
|
hlcol: !byte 0 ; mark_slots color parameter
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|
latwcol: !byte 0 ; draw_lattice colors: walls, posts
|
|
latpcol: !byte 0
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|
frame8: !byte 0 ; framectr / 8: the animation beat
|
|
ei: !byte 0 ; enemy loop index
|
|
etries: !byte 0
|
|
etd: !byte 0
|
|
gcx: !byte 0 ; maze generator state
|
|
gcy: !byte 0
|
|
gsp: !byte 0
|
|
gn: !byte 0
|
|
gtd: !byte 0
|
|
gnx: !byte 0
|
|
gny: !byte 0
|
|
gdlist: !fill 4, 0
|
|
ex: !fill NENEMIES, 0 ; enemy positions, headings, colors
|
|
ey: !fill NENEMIES, 0
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|
edir: !fill NENEMIES, 0
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|
ecol: !fill NENEMIES, 0
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|
edead: !fill NENEMIES, 0 ; respawn countdown, 0 = alive
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|
|
|
; ---- maze generator buffers ----
|
|
visited: !fill NCELLS, 0
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|
stackx: !fill NCELLS, 0
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|
stacky: !fill NCELLS, 0
|