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Progressive pixel layout

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Brooke Vibber 2024-02-04 14:25:15 -08:00
parent 510457f97a
commit c152c4346b
2 changed files with 62 additions and 5 deletions
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63
mandel.s
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@ -31,7 +31,7 @@ pixel_color = $b8 ; u8
pixel_mask = $b9 ; u8 pixel_mask = $b9 ; u8
pixel_shift = $ba ; u8 pixel_shift = $ba ; u8
pixel_offset = $bb ; u8 pixel_offset = $bb ; u8
fill_level = $bc ; u8
; FP registers in zero page ; FP registers in zero page
FR0 = $d4 ; float48 FR0 = $d4 ; float48
@ -218,6 +218,15 @@ z_buffer:
.export start .export start
max_fill_level = 6
fill_masks:
.byte %00011111
.byte %00001111
.byte %00000111
.byte %00000011
.byte %00000001
.byte %00000000
; 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
@ -959,6 +968,11 @@ copy_byte_loop:
jsr SETVBV jsr SETVBV
main_loop: main_loop:
lda #0
sta fill_level
fill_loop:
; sy = -92 .. 91 ; sy = -92 .. 91
lda #(256-half_height) lda #(256-half_height)
sta sy sta sy
@ -973,6 +987,40 @@ loop_sy:
sta sx + 1 sta sx + 1
loop_sx: loop_sx:
; check the fill mask
ldy #0
loop_skip_level:
cpy fill_level
beq current_level
lda fill_masks,y
and sx
bne not_skipped_mask1
lda fill_masks,y
and sy
beq skipped_mask
not_skipped_mask1:
iny
jmp loop_skip_level
current_level:
lda fill_masks,y
and sx
bne skipped_mask
lda fill_masks,y
and sy
beq not_skipped_mask
skipped_mask:
jmp skipped
not_skipped_mask:
; run the fractal!
zoom_factor cx, sx, zoom, aspect_x zoom_factor cx, sx, zoom, aspect_x
add16 cx, cx, ox add16 cx, cx, ox
zoom_factor cy, sy, zoom, aspect_y zoom_factor cy, sy, zoom, aspect_y
@ -983,7 +1031,7 @@ loop_sx:
jsr keycheck jsr keycheck
beq no_key beq no_key
; @fixme clear the pixel stats ; @fixme clear the pixel stats
jmp main_loop jmp fill_loop
no_key: no_key:
; check if we should update the counters ; check if we should update the counters
@ -997,7 +1045,7 @@ no_key:
; count_frames >= 120? update! ; count_frames >= 120? update!
lda count_frames lda count_frames
cmp #120 ; >= 2 seconds cmp #120 ; >= 2 seconds
bmi skip_status bmi skipped
update_status: update_status:
; FR0 = (float)count_pixels & clear count_pixels ; FR0 = (float)count_pixels & clear count_pixels
@ -1061,7 +1109,7 @@ update_status:
draw_text_indirect speed_start, speed_precision, INBUFF draw_text_indirect speed_start, speed_precision, INBUFF
draw_text speed_start + speed_precision, str_speed_len, str_speed draw_text speed_start + speed_precision, str_speed_len, str_speed
skip_status: skipped:
clc clc
lda sx lda sx
@ -1095,6 +1143,13 @@ loop_sy_done:
draw_text 40 - str_done_len, str_done_len, str_done draw_text 40 - str_done_len, str_done_len, str_done
fill_loop_done:
inc fill_level
lda fill_level
cmp #max_fill_level
beq loop
jmp fill_loop
loop: loop:
; finished ; finished
jsr keycheck jsr keycheck

4
readme.md
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@ -14,7 +14,7 @@ Non-goals:
Enjoy! I'll probably work on this off and on for the next few weeks until I've got it producing fractals. Enjoy! I'll probably work on this off and on for the next few weeks until I've got it producing fractals.
-- brion, january 2023 -- brooke, january 2023 - february 2024
## Current state ## Current state
@ -28,6 +28,8 @@ The mandelbrot calculations are done using 4.12-precision fixed point numbers. I
Iterations are capped at 255. Iterations are capped at 255.
The pixels are run in a progressive layout to get the basic shape on screen faster.
## Next steps ## Next steps
Add a running counter of ms/px using the vertical blank interrupts as a timer. This'll show how further work improves it! Add a running counter of ms/px using the vertical blank interrupts as a timer. This'll show how further work improves it!