brooke/mandel-6502
1
0
Fork 1
Code Issues Pull requests Projects Releases Packages Wiki Activity

add an alternate viewport (compile-time currently)

Browse source 
zoomed to max
This commit is contained in:
Brooke Vibber 2024-12-29 13:10:35 -08:00
parent 0fc5ba914f
commit 2118890977
1 changed files with 31 additions and 9 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

40
mandel.s
View file

@ -246,6 +246,18 @@ fill_masks:
.byte %00000001 .byte %00000001
.byte %00000000 .byte %00000000
viewport_zoom:
.byte 1
.byte 8
viewport_ox:
.word $0000
.word $f110
viewport_oy:
.word $0000
.word $fbe0
; 2 + 9 * byte cycles ; 2 + 9 * byte cycles
.macro add bytes, dest, arg1, arg2 .macro add bytes, dest, arg1, arg2
clc ; 2 cyc clc ; 2 cyc
@ -1213,13 +1225,27 @@ zero_byte_loop:
jsr imul8xe_init jsr imul8xe_init
; ox = 0; oy = 0 ; initialize viewport
;ldx #0 ; overview
ldx #1 ; closeup
lda viewport_zoom,x
sta zoom
txa
asl a
tax
lda viewport_ox,x
sta ox
lda viewport_oy,x
sta oy
inx
lda viewport_ox,x
sta ox + 1
lda viewport_oy,x
sta oy + 1
; count_frames = 0; count_pixels = 0 ; count_frames = 0; count_pixels = 0
lda #0 lda #0
sta ox
sta ox + 1
sta oy
sta oy + 1
sta count_frames sta count_frames
sta count_pixels sta count_pixels
@ -1229,10 +1255,6 @@ zero_byte_loop:
ldx #total_pixels ldx #total_pixels
jsr ZF1 jsr ZF1
; zoom = 2x
lda #1
sta zoom
; Disable display DMA ; Disable display DMA
lda #0 lda #0
sta DMACTL sta DMACTL