847 lines
17 KiB
ArmAsm
847 lines
17 KiB
ArmAsm
;=======================================================================
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; Based on BASIC program posted by FozzTexx, originally written in 1987
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;=======================================================================
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; State:
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; 0: Launch Rocket -> goes to 1
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; 1: Move Rocket -> repeats 1 until CS done, then 2
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; 2: Start Explosion -> goes to 3
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; 3: Continue Explosion -> repeats 3 until done.
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; then randomly might go to 2
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; before going to 0
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STATE_LAUNCH_ROCKET = 0
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STATE_MOVE_ROCKET = 2
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STATE_START_EXPLOSION = 4
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STATE_CONTINUE_EXPLOSION = 6
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STATE_STALL_ROCKET = 8
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; Constants
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NUMSTARS = 16
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YSIZE = 160
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XSIZE = 280
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MARGIN = 24
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; Zero page addresses
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;STATE = $ED
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;OFFSET = $EF
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COLOR_GROUP = $F0
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X_VELOCITY = $F1
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Y_VELOCITY_H = $F2
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Y_VELOCITY_L = $F3
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MAX_STEPS = $F4
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XPOS_H = $F5
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XPOS_L = $F6
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YPOS_H = $F7
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YPOS_L = $F8
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PEAK = $F9
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CURRENT_STEP = $FA
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Y_OLD = $FB
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Y_OLDER = $FC
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X_OLD = $FD
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X_OLDER = $FE
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FWTEMP = $FF
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;.align $100
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;===========================
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; LAUNCH_FIREWORK
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;===========================
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; cycles= 60+60+67+60+56+56+15+8+21+11 = 414
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launch_firework:
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sound1:
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bit SPEAKER ; 4
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jsr random16 ; 6+42
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lda SEEDL ; 3
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and #$4 ; 2
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sta COLOR_GROUP ; HGR color group (0 PG or 4 BO) ; 3
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;============
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; 60
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jsr random16 ; 6+42
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lda SEEDL ; 3
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and #$3 ; 2
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clc ; 2
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adc #$1 ; 2
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sta X_VELOCITY ; x velocity = 1..4 ; 3
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;===========
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; 60
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jsr random16 ; 6+42
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lda SEEDL ; 3
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and #$3 ; 2
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clc ; 2
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adc #$2 ; 2
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eor #$ff ; 2
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sta Y_VELOCITY_H ; y velocity = -3..-6 ; 3
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lda #0 ; 2
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sta Y_VELOCITY_L ; it's 8:8 fixed point ; 3
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;============
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; 67
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jsr random16 ; 6+42
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lda SEEDL ; 3
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and #$1f ; 2
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clc ; 2
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adc #33 ; 2
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sta MAX_STEPS ; 33..64 ; 3
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;============
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; 60
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; launch from the two hills
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jsr random16 ; 6+42
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lda SEEDL ; 3
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and #$3f ; 2
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sta XPOS_L ; base of 0..63 ; 3
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;============
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; 56
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jsr random16 ; 6+42
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lda SEEDL ; 3
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and #$1 ; 2
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beq right_hill ; 3
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;============
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; 56
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left_hill: ;-1
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lda X_VELOCITY ; nop ; 3
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lda X_VELOCITY ; nop ; 3
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lda X_VELOCITY ; nop ; 3
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nop ; 2
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lda #24 ; make it 24..87 ; 2
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jmp done_hill ; 3
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;===========
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; 15
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right_hill:
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lda X_VELOCITY ; 3
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eor #$ff ; 2
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sta X_VELOCITY ; 3
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inc X_VELOCITY ; aim toward middle ; 5
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lda #191 ; make it 191..254 ; 2
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;===========
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; 15
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done_hill:
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clc ; 2
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adc XPOS_L ; 3
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sta XPOS_L ; 3
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;===========
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; 8
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lda #YSIZE ; 2
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sta YPOS_H ; 3
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lda #0 ; fixed point 8:8 ; 2
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sta YPOS_L ; start at ground ; 3
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lda YPOS_H ; 3
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sta PEAK ; peak starts at ground ; 3
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lda #1 ; 2
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sta CURRENT_STEP ; 3
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;===========
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; 21
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lda #STATE_MOVE_ROCKET ; 2
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sta STATE ; move to launch ; 3
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rts ; 6
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;============
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; 11
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.align $100
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;==========================================================================
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; Move rocket
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;==========================================================================
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; cycles=24+11+20+18+14+53 = 140+1096 = 1236
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move_rocket:
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; save old values
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lda Y_OLD ; 3
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sta Y_OLDER ; 3
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lda YPOS_H ; 3
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sta Y_OLD ; 3
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lda X_OLD ; 3
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sta X_OLDER ; 3
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lda XPOS_L ; 3
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sta X_OLD ; 3
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;===========
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; 24
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; Move xpos
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lda XPOS_L ; 3
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clc ; 2
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adc X_VELOCITY ; 3
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sta XPOS_L ; 3
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;============
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; 11
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; Move ypos, 16-bit add
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clc ; 2
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lda YPOS_L ; 3
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adc Y_VELOCITY_L ; 3
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sta YPOS_L ; 3
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lda YPOS_H ; 3
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adc Y_VELOCITY_H ; 3
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sta YPOS_H ; 3
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;===========
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; 20
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; adjust Y velocity, slow it down
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clc ; 2
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lda Y_VELOCITY_L ; 3
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adc #$20 ; $20 = 0.125 ; 2
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sta Y_VELOCITY_L ; 3
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lda Y_VELOCITY_H ; 3
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adc #0 ; 2
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sta Y_VELOCITY_H ; 3
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;===========
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; 18
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; if we went higher, adjust peak
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lda YPOS_H ; 3
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cmp PEAK ; 3
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bcc no_peak_nop ; blt ; 3
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;-1
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sta PEAK ; 3
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jmp no_peak ; 3
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no_peak_nop:
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nop ; 2
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jmp no_peak ; 3
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no_peak:
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;=============
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; 14
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;========================================
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; Check if out of bounds and stop moving
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;========================================
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; bcc = 8+7+12+20+6 = 53
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; bcs/bcc = 8+7+12+20+6 = 53
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; bcs/bcs/bmi = 8+7+5+33 = 53
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; bcs/bcs/bpl/bcs = 8+7+5+7+20+6 = 53
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; bcs/bcs/bpl/bcc/bcc = 8+7+5+7+20+6 = 53
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; bcs/bcs/bpl/bcc/bcs = 8+7+5+7+20+6 = 53
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lda XPOS_L ; if (xpos_l<=margin) too far left ; 3
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cmp #MARGIN ; 2
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bcc done_moving_first ; 3
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;===========
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; 8
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; Due to 256 wraparound, the above will catch this case???
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; cmp #XSIZE-MARGIN ; if (xpos_l>=(xsize-margin)) too far right
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; bcs done_moving
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; -1
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lda YPOS_H ; if (ypos_h<=margin) too far up ; 3
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cmp #MARGIN ; 2
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bcc done_moving_second ; 3
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;===========
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; 7
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;======================
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; if falling downward
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;======================
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; -1
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lda Y_VELOCITY_H ; 3
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bmi going_up ; if (y_velocity_h>0) ; 3
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;============
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; 5
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; if too close to ground, explode ; -1
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lda YPOS_H ; if (ypos_h>=ysize-margin) ; 3
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cmp #(YSIZE-MARGIN) ; 2
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bcs done_moving_third ; 3
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;============
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; 7
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; if fallen a bit past peak, explode ; -1
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sec ; if (ypos_h>ysize-(ysize-peak)/2) ; 2
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lda #YSIZE ; 2
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sbc PEAK ; 3
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lsr ; 2
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eor #$FF ; 2
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sec ; 2
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adc #YSIZE ; 2
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cmp YPOS_H ; 3
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bcc done_moving ; 3
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;===========
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; 20
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;-1
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done_moving_ft:
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nop ; 2
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nop ; 2
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jmp done_bounds_checking ; 3
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;===========
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; 6
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going_up:
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; 33 cycles
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lda MAX_STEPS ; 3
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lda MAX_STEPS ; 3
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lda MAX_STEPS ; 3
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lda MAX_STEPS ; 3
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lda MAX_STEPS ; 3
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lda MAX_STEPS ; 3
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lda MAX_STEPS ; 3
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nop ; 2
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jmp done_moving_ft ; 3+7
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done_moving_first:
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; 7 cycles
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lda MAX_STEPS ; 3
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nop ; 2
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nop ; 2
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done_moving_second:
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; 12 cycles
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lda MAX_STEPS ; 3
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nop ; 2
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lda MAX_STEPS ; 3
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nop ; 2
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nop ; 2
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done_moving_third:
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; 20 cycles
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lda MAX_STEPS ; 3
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lda MAX_STEPS ; 3
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lda MAX_STEPS ; 3
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lda MAX_STEPS ; 3
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lda MAX_STEPS ; 3
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lda MAX_STEPS ; 3
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nop ; 2
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done_moving:
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lda MAX_STEPS ; 3
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sta CURRENT_STEP ; 3
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;============
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; 6
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done_bounds_checking:
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;=======================================================================
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; draw rocket
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;=======================================================================
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;
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; cs!=mx 9+15+258+258+3+10+258+258+9+7+11 = 1096
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; cs==mx 9+ + + + +10+258+258+9+7+11 = 562 (need 534)
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draw_rocket:
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lda CURRENT_STEP ; 3
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cmp MAX_STEPS ; 3
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beq skip_drawing_rocket ; 3
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;===========
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; 9
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; set hcolor to proper white (3 or 7)
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;-1
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clc ; 2
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lda COLOR_GROUP ; 3
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adc #3 ; 2
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tax ; 2
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lda colortbl,X ; get color from table ; 4+
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sta HGR_COLOR ; 3
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;============
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; 15
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; HPLOT X,Y: X= (y,x), Y=a
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ldx X_OLD ; 3
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lda Y_OLD ; 3
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ldy #0 ; 2
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jsr hplot0 ; hplot(x_old,y_old); ;6+244
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;=============
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; 258
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; HPLOT TO X,Y X=(x,a), y=Y
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ldx XPOS_L ; 3
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ldy #0 ; 2
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lda YPOS_H ; 3
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jsr hplot0 ;6+244
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;=============
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; 258
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; lda XPOS_L ; 3
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; ldx #0 ; 2
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; ldy YPOS_H ; 3
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; jsr hglin ; hplot_to(xpos_l,ypos_h); ;?????
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jmp erase_rocket ; 3
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skip_drawing_rocket:
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; Try X=7 Y=13 cycles=534
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ldy #13 ; 2
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sdloop1:ldx #7 ; 2
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sdloop2:dex ; 2
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bne sdloop2 ; 2nt/3
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dey ; 2
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bne sdloop1 ; 2nt/3
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erase_rocket:
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; erase with proper color black (0 or 4)
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ldx COLOR_GROUP ; 3
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lda colortbl,X ; get color from table ; 4+
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sta HGR_COLOR ; 3
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;===========
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; 10
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; HPLOT X,Y: X= (y,x), Y=a
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ldx X_OLDER ; 3
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lda Y_OLDER ; 3
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ldy #0 ; 2
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jsr hplot0 ; hplot(x_old,y_old); ; 6+244
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;============
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; 258
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; HPLOT TO X,Y X=(x,a), y=Y
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ldx X_OLD ; 3
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ldy #0 ; 2
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lda Y_OLD ; 3
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jsr hplot0 ;6+244
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;=============
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; 258
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; lda X_OLD
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; ldx #0
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; ldy Y_OLD
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; jsr hglin ; hplot_to(x_old,y_old);
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done_with_loop:
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lda CURRENT_STEP ; 3
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cmp MAX_STEPS ; 3
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bne not_done_with_launch ; 3
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;=============
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; 9
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;-1
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lda #STATE_START_EXPLOSION ; 2
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sta STATE ; 3
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jmp not_done_with_launch2 ; 3
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;==========
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; 7
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not_done_with_launch:
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lda #STATE_STALL_ROCKET ; 2
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sta STATE ; 3
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nop ; 2
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;==========
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; 7
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not_done_with_launch2:
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inc CURRENT_STEP ; 5
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rts ; 6
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;===========
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; 11
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.align $100
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;======================================================================
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; Start explosion near x_old, y_old
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;======================================================================
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; cycles = 67+16+63+16+258+20 = 440
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;
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start_explosion:
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; Set X position
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lda #0 ; 2
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sta XPOS_H ; 3
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jsr random16 ; 6+42
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lda SEEDL ; 3
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and #$f ; 0..15 ; 2
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sec ; 2
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sbc #8 ; -8..7 ; 2
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clc ; 2
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bmi signextend_neg ; 3
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;============
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; 67
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;-1
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adc X_OLD ; 3
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sta XPOS_L ; xpos=x_old+(random()%16)-8; x +/- 8 ; 3
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lda #0 ; 2
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adc XPOS_H ; 3
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sta XPOS_H ; 3
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jmp exp_sub_done ; 3
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;===========
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; 16
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signextend_neg:
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adc X_OLD ; 3
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sta XPOS_L ; xpos=x_old+(random()%16)-8; x +/- 8 ; 3
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lda #$ff ; 2
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adc XPOS_H ; 3
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sta XPOS_H ; 3
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nop ; 2
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;===========
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; 16
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exp_sub_done:
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; set Y position
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jsr random16 ; 6+42
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lda SEEDL ; 3
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and #$f ; 0..15 ; 2
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sec ; 2
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sbc #8 ; -8..7 ; 2
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adc Y_OLD ; 3
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sta YPOS_H ; ypos_h=y_old+(random()%16)-8; y +/- 8 ; 3
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;============
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; 63
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; draw white (with fringes)
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lda COLOR_GROUP ; 3
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clc ; 2
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adc #$3 ; 2
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tax ; 2
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lda colortbl,X ; get color from table ; 4+
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sta HGR_COLOR ; 3
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;===========
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; 16
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; hplot(xpos,ypos_h); draw at center of explosion
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; HPLOT X,Y: X= (y,x), Y=a
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ldx XPOS_L ; 3
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lda YPOS_H ; 3
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ldy #0 ; never above 255 ; 2
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jsr hplot0 ; hplot(x_old,y_old); ; 6+244
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;==============
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; 258
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; Make sound and ready explosion
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sound3:
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bit SPEAKER ; 4
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ldy #1 ; 2
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sty FWTEMP ; save Y ; 3
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; move to continue explosion
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lda #STATE_CONTINUE_EXPLOSION ; 2
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sta STATE ; 3
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rts ; 6
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;=============
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; 20
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;==========================================================================
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; Continue Explosion
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;==========================================================================
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;
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; cycles cpy!=9 : 8+2233+2227+13+5 = 4486
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; cpy==9 : 8+ +2227+13+62 = 2310 waste 2176
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continue_explosion:
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ldy FWTEMP ; 3
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;================================
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; Draw spreading dots in white
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cpy #9 ; 2
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beq explosion_erase_waste ; 3
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;===========
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; 8
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; -1
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; hcolor_equals(color_group+3);
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lda COLOR_GROUP ; 3
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clc ; 2
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adc #$3 ; 2
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tax ; 2
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lda colortbl,X ; get color from table ; 4+
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sta HGR_COLOR ; 3
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ldx FWTEMP ; 3
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stx OFFSET ; 3
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jsr explosion ; 6+2203
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jmp explosion_erase ; 3
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;============
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; 2233
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explosion_erase_waste:
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; waste 2176-4 = 2172
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sound2:
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; bit SPEAKER ; 4
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nop
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nop
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; Try X=47 Y=9 cycles=2170 R2
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nop ; 2
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ldy #9 ; 2
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eeloop1:ldx #47 ; 2
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eeloop2:dex ; 2
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bne eeloop2 ; 2nt/3
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dey ; 2
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bne eeloop1 ; 2nt/3
|
|
|
|
|
|
|
|
explosion_erase:
|
|
;======================
|
|
; erase old
|
|
|
|
; erase with proper color black (0 or 4)
|
|
|
|
ldx COLOR_GROUP ; 3
|
|
lda colortbl,X ; get color from table ; 4+
|
|
sta HGR_COLOR ; 3
|
|
|
|
ldx FWTEMP ; 3
|
|
dex ; 2
|
|
stx OFFSET ; 3
|
|
|
|
jsr explosion ; 6+2203
|
|
;==============
|
|
; 2227
|
|
done_with_explosion:
|
|
|
|
; lda #$c0 ;
|
|
; jsr WAIT ;
|
|
|
|
inc FWTEMP ; 5
|
|
lda FWTEMP ; 3
|
|
cmp #10 ; 2
|
|
beq explosion_done ; 3
|
|
;=============
|
|
; 13
|
|
|
|
; -1
|
|
rts ; 6
|
|
|
|
explosion_done:
|
|
;==================================
|
|
; randomly draw more explosions
|
|
;==================================
|
|
jsr random16 ; 6+42
|
|
lda SEEDL ; 3
|
|
and #$4 ; 2
|
|
sta STATE ; 3
|
|
|
|
; if 0, then move to state 0 (start over)
|
|
; if 1, then move to state 4 (new random explosion)
|
|
|
|
rts ; 6
|
|
;============
|
|
; 62
|
|
|
|
|
|
.align $100
|
|
|
|
;===============================
|
|
; Draw explosion rays
|
|
;===============================
|
|
;
|
|
; Note: the western pixels don't do the full 16-bit math
|
|
; as currently it's not possible for those to overflow 256
|
|
;
|
|
; cycles = 275+275+270+270+272+278+278+279+6=2203
|
|
|
|
explosion:
|
|
|
|
; HPLOT X,Y: X= (y,x), Y=a
|
|
|
|
; Southeast pixel
|
|
clc ; 2
|
|
lda XPOS_L ; 3
|
|
adc OFFSET ; 3
|
|
tax ; 2
|
|
lda XPOS_H ; 3
|
|
adc #0 ; 2
|
|
tay ; 2
|
|
clc ; 2
|
|
lda YPOS_H ; 3
|
|
adc OFFSET ; 3
|
|
jsr hplot0 ; hplot(xpos+o,ypos_h+o); ; 6+244
|
|
;==============
|
|
; 275
|
|
|
|
; Northeast Pixel
|
|
clc ; 2
|
|
lda XPOS_L ; 3
|
|
adc OFFSET ; 3
|
|
tax ; 2
|
|
lda XPOS_H ; 3
|
|
adc #0 ; 2
|
|
tay ; 2
|
|
sec ; 2
|
|
lda YPOS_H ; 3
|
|
sbc OFFSET ; 3
|
|
jsr hplot0 ; hplot(xpos+o,ypos_h-o); ; 6+244
|
|
;==============
|
|
; 275
|
|
|
|
; Northwest Pixel
|
|
sec ; 2
|
|
lda XPOS_L ; 3
|
|
sbc OFFSET ; 3
|
|
tax ; 2
|
|
ldy #0 ; 2
|
|
sec ; 2
|
|
lda YPOS_H ; 3
|
|
sbc OFFSET ; 3
|
|
jsr hplot0 ; hplot(xpos-o,ypos_h-o); NW ; 6+244
|
|
;==============
|
|
; 270
|
|
|
|
; Southwest Pixel
|
|
sec ; 2
|
|
lda XPOS_L ; 3
|
|
sbc OFFSET ; 3
|
|
tax ; 2
|
|
ldy #0 ; 2
|
|
clc ; 2
|
|
lda YPOS_H ; 3
|
|
adc OFFSET ; 3
|
|
jsr hplot0 ; hplot(xpos-o,ypos_h+o); SW ; 6+244
|
|
;=============
|
|
; 270
|
|
|
|
; HPLOT X,Y: X= (y,x), Y=a
|
|
|
|
; South Pixel
|
|
ldx XPOS_L ; 3
|
|
ldy XPOS_H ; 3
|
|
clc ; 2
|
|
lda OFFSET ; 3
|
|
adc OFFSET ; 3
|
|
adc OFFSET ; 3
|
|
lsr ; 2
|
|
adc YPOS_H ; 3
|
|
jsr hplot0 ; hplot(xpos,ypos_h+(o*1.5)); S ; 6+244
|
|
;=============
|
|
; 272
|
|
|
|
; North Pixel
|
|
ldx XPOS_L ; 3
|
|
ldy XPOS_H ; 3
|
|
clc ; O O*1.5 NEG ; 2
|
|
lda OFFSET ; 0 = 0 0 ; 3
|
|
adc OFFSET ; 1 = 1 -1 ; 3
|
|
adc OFFSET ; 2 = 3 -3 ; 3
|
|
lsr ; 3 = 4 -4 ; 2
|
|
eor #$FF ; 4 = 6 -6 ; 2
|
|
clc ; 2
|
|
adc #1 ; 2
|
|
adc YPOS_H ; 3
|
|
jsr hplot0 ; hplot(xpos,ypos_h-(o*1.5)); N ; 6+244
|
|
;==============
|
|
; 278
|
|
|
|
; HPLOT X,Y: X= (y,x), Y=a
|
|
|
|
; East Pixel
|
|
clc ; 2
|
|
lda OFFSET ; 3
|
|
adc OFFSET ; 3
|
|
adc OFFSET ; 3
|
|
lsr ; 2
|
|
adc XPOS_L ; 3
|
|
tax ; 2
|
|
lda #0 ; 2
|
|
adc XPOS_H ; 3
|
|
tay ; 2
|
|
lda YPOS_H ; 3
|
|
jsr hplot0 ; hplot(xpos+(o*1.5),ypos_h); E ; 6+244
|
|
;==============
|
|
; 278
|
|
|
|
; West Pixel
|
|
clc ; O O*1.5 NEG ; 2
|
|
lda OFFSET ; 0 = 0 0 ; 3
|
|
adc OFFSET ; 1 = 1 -1 ; 3
|
|
adc OFFSET ; 2 = 3 -3 ; 3
|
|
lsr ; 3 = 4 -4 ; 2
|
|
eor #$FF ; 4 = 6 -6 ; 2
|
|
clc ; 2
|
|
adc #1 ; 2
|
|
adc XPOS_L ; 3
|
|
tax ; 2
|
|
ldy #0 ; 2
|
|
lda YPOS_H ; 3
|
|
jsr hplot0 ; hplot(xpos-(o*1.5),ypos_h); W ; 6+244
|
|
;==============
|
|
; 279
|
|
|
|
rts ; 6
|
|
|
|
|
|
|
|
;=========================================================================
|
|
; Draw the stars
|
|
;=========================================================================
|
|
; 7+ 280X + 5
|
|
; 16 stars = 4492
|
|
|
|
|
|
.align $100
|
|
draw_stars:
|
|
; HCOLOR = 3, white (though they are drawn purple)
|
|
lda #$7f ; 2
|
|
sta HGR_COLOR ; 3
|
|
ldy #0 ; 2
|
|
;===========
|
|
; 7
|
|
|
|
star_loop:
|
|
tya ; 2
|
|
pha ; 3
|
|
|
|
; HPLOT X,Y
|
|
; X= (y,x), Y=a
|
|
|
|
ldx stars,Y ; 4+
|
|
lda stars+1,Y ; 4+
|
|
ldy #0 ; 2
|
|
|
|
jsr hplot0 ;6+244
|
|
|
|
pla ; 4
|
|
tay ; 2
|
|
|
|
iny ; 2
|
|
iny ; 2
|
|
cpy #NUMSTARS*2 ; 2
|
|
|
|
bne star_loop ; 3
|
|
;============
|
|
; 279
|
|
|
|
; -1
|
|
rts ; 6
|
|
|
|
stars: ; even x so they are purple
|
|
.byte 28,107, 108, 88, 126, 88, 136, 95
|
|
.byte 150,108, 148,120, 172,124, 180,109
|
|
.byte 216, 21, 164, 40, 124, 18, 60, 12
|
|
.byte 240,124, 94,125, 12, 22, 216,116
|
|
|
|
|
|
; moved to letters.s
|
|
; fw_letters:
|