-
Notifications
You must be signed in to change notification settings - Fork 23
/
plasma_bot.s
220 lines (153 loc) · 3.71 KB
/
plasma_bot.s
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
; do a (hopefully fast) plasma type demo
; 151 -- original
; 137 -- optimize generation
; 136 -- align lookup table so we can index it easier
; 130 -- optimize indexing of lookup
; 126 -- run loops backaward
; 124 -- notice X already 0 before plot
; 131 -- use GBASCALC. much faster, but 7 bytes larger
; 129 -- run loop backwards
; 128 -- set color ourselves
; 127 -- overlap color lookup with sine table
; 119 -- forgot to comment out unused
; 121 -- make it use full screen (40x48)
; 149 -- add page flipping
; 144 -- optimize a bit
; 141 -- smc DRAW_PAGE
; 144 -- for bot, backwards jump
; 142 -- from qkumba, remove php/plp
; 141 -- from qkumba, remove SAVEX
; goal=135
.include "zp.inc"
.include "hardware.inc"
CTEMP = $FC
;SAVEOFF = $FD
;SAVEX = $FE
;SAVEY = $FF
;================================
; Clear screen and setup graphics
;================================
plasma:
jsr SETGR ; set lo-res 40x40 mode
bit FULLGR ; make it 40x48
; color = ( 8.0 + 8*sin(x) + 8.0 + 8*sin(y) )/2
; becomes
; color = ( 16 + (sintable[xx&0xf]) + (sintable[yy&0xf])) / 2;
; we only create a 16x16 texture, which we pattern across 40x48 screen
create_lookup:
ldy #15
create_yloop:
ldx #15
create_xloop:
clc
lda #15 ; 8+8 (but 15 works better)
adc sinetable,X
adc sinetable,Y
lsr
lookup_smc:
sta lookup ; always starts at $d00
inc lookup_smc+1
dex
bpl create_xloop
dey
bpl create_yloop
; X and Y both $FF
create_lookup_done:
forever_loop:
cycle_colors:
; cycle colors
; can't do palette rotate on Apple II so faking it here
; just incrementing every entry in texture by 1
; X if $FF when arriving here
; ldx #0
inx ; make X 0
cycle_loop:
inc lookup,X
inx
bne cycle_loop
; set/flip pages
; we want to flip pages and then draw to the offscreen one
flip_pages:
; ldx #0 ; x already 0
lda draw_page_smc+1 ; DRAW_PAGE
beq done_page
inx
done_page:
ldy PAGE1,X ; set display page to PAGE1 or PAGE2
eor #$4 ; flip draw page between $400/$800
sta draw_page_smc+1 ; DRAW_PAGE
; plot current frame
; scan whole 40x48 screen and plot each point based on
; lookup table colors
plot_frame:
ldx #47 ; YY=47 (count backwards)
plot_yloop:
txa ; get (y&0xf)<<4
pha ; save YY / SAVEX
asl
asl
asl
asl
sta CTEMP ; save for later
txa ; get Y in accumulator
lsr ; call actually wants Ycoord/2
ldy #$0f ; setup mask for odd/even line
bcc plot_mask
ldy #$f0
plot_mask:
sty MASK
jsr GBASCALC ; point GBASL/H to address in (A is ycoord/2)
; after, A is GBASL, C is clear
lda GBASH ; adjust to be PAGE1/PAGE2 ($400 or $800)
draw_page_smc:
adc #0
sta GBASH
;==========
ldy #39 ; XX = 39 (countdown)
plot_xloop:
; stx SAVEX ; SAVE YY
tya ; get x&0xf
and #$f
ora CTEMP ; combine with val from earlier
; get ((y&0xf)*16)+x
tax
plot_lookup:
; sta plot_lookup_smc+1
plot_lookup_smc:
lda lookup,X ; load lookup, (y*16)+x
; lda lookup ; load lookup, (y*16)+x
and #$f
lsr ; we actually only have 8 colors
tax
lda colorlookup,X ; lookup color
sta COLOR ; each nibble should be same
jsr PLOT1 ; plot at GBASL,Y (x co-ord goes in Y)
; ldx SAVEX ; restore YY
dey
bpl plot_xloop
pla
tax
dex
bpl plot_yloop
bmi forever_loop
colorlookup:
bw_color_lookup:
; blue
;.byte $55,$22,$66,$77,$ff,$77,$55 ; ,$00 shared w sin table
; pink
.byte $55,$11,$33,$bb,$ff,$bb,$55
; this is actually 8*sin(x)
sinetable:
.byte $00,$03,$05,$07,$08,$07,$05,$03
.byte $00,$FD,$FB,$F9,$F8,$F9,$FB,$FD
;colorlookup:
;.byte $00,$00,$05,$05,$07,$07,$0f,$0f
;.byte $07,$07,$06,$06,$02,$02,$05,$05
;.byte $00,$55,$77,$ff,$77,$66,$22,$55
; want this to be at 3f5
; Length is 141 so start at $3f4 -
; 1013 - 141 + 3 = 875 = $36B
jmp plasma
; make lookup happen at page boundary
.org $d00
lookup: