prog8/examples/cx16/life.p8
2024-09-06 16:39:44 +02:00

140 lines
4.4 KiB
Lua

; conway's game of life.
%import math
%import textio
main {
const ubyte WIDTH = 80
const ubyte HEIGHT = 60-4
const uword STRIDE = $0002+WIDTH
uword world1 = memory("world1", (WIDTH+2)*(HEIGHT+2), 0)
uword world2 = memory("world2", (WIDTH+2)*(HEIGHT+2), 0)
uword @requirezp active_world = world1
sub start() {
; cx16.set_screen_mode(3)
txt.cls()
txt.color(8)
txt.plot(50,0)
txt.print("prog8 - conway's game of life")
sys.memset(world1, (WIDTH+2)*(HEIGHT+2), 0)
sys.memset(world2, (WIDTH+2)*(HEIGHT+2), 0)
set_start_gen()
ubyte gen_add
uword gen
repeat {
if gen_add==0
cbm.SETTIM(0,0,0)
next_gen()
gen++
txt.home()
txt.color(5)
txt.print(" gen ")
txt.print_uw(gen)
gen_add++
if gen_add==10 {
txt.print(" jiffies/10 gens: ")
txt.print_uw(cbm.RDTIM16())
txt.print(" ")
gen_add=0
}
}
}
sub set_start_gen() {
; some way to set a custom start generation:
; str start_gen = " " +
; " " +
; " " +
; " ** " +
; " * * " +
; " * " +
; " * * " +
; " ****** " +
; " " +
; " " +
; " " +
; " " +
; " " +
; " " +
; " " +
; " "
;
; for y in 0 to 15 {
; for x in 0 to 15 {
; if start_gen[y*16 + x]=='*'
; active_world[offset + x] = 1
; }
; offset += STRIDE
; }
; randomize whole world
uword offset = STRIDE+1
ubyte x
ubyte y
for y in 0 to HEIGHT-1 {
for x in 0 to WIDTH-1 {
active_world[offset+x] = math.rnd() & 1
}
offset += STRIDE
}
}
sub next_gen() {
const ubyte DXOFFSET = 0
const ubyte DYOFFSET = 2
ubyte[2] cell_chars = [sc:' ', sc:'●']
uword @requirezp new_world = world1
if active_world == world1
new_world = world2
; To avoid re-calculating word index lookups into the new- and active world arrays,
; we calculate the required pointer values upfront.
; Inside the loop we can use ptr+x just fine (results in efficient LDA (ptr),Y instruction because x is a byte type),
; and for each row we simply add the stride to the pointer.
; It's more readable to use active_world[offset] etc, but offset is a word value, and this produces
; inefficient assembly code because we can't use a register indexed mode in this case. Costly inside a loop.
uword @requirezp new_world_ptr = new_world + STRIDE+1-DXOFFSET
uword @requirezp active_world_ptr = active_world + STRIDE+1-DXOFFSET
ubyte x
ubyte y
for y in DYOFFSET to HEIGHT+DYOFFSET-1 {
cx16.vaddr_autoincr(1, $b000 + 256*y, 0, 2) ; allows us to use simple Vera data byte assigns later instead of setchr() calls
for x in DXOFFSET to WIDTH+DXOFFSET-1 {
; count the living neighbors
ubyte cell = @(active_world_ptr + x)
uword @requirezp ptr = active_world_ptr + x - STRIDE - 1
ubyte neighbors = @(ptr) + @(ptr+1) + @(ptr+2) +
@(ptr+STRIDE) + cell + @(ptr+STRIDE+2) +
@(ptr+STRIDE*2) + @(ptr+STRIDE*2+1) + @(ptr+STRIDE*2+2)
; apply game of life rules
if neighbors==3
cell=1
else if neighbors!=4
cell=0
@(new_world_ptr + x) = cell
; draw new cell
; txt.setchr(x,y,cell_chars[cell])
cx16.VERA_DATA0 = cell_chars[cell]
}
active_world_ptr += STRIDE
new_world_ptr += STRIDE
}
active_world = new_world
}
}