prog8/examples/cx16/mandelbrot.p8
2020-08-30 19:31:20 +02:00

43 lines
1.1 KiB
Lua

%import cx16textio
%import cx16flt
%zeropage basicsafe
main {
const uword width = 60
const uword height = 50
const ubyte max_iter = 16
sub start() {
txt.print("calculating mandelbrot fractal...\n\n")
ubyte pixelx
ubyte pixely
for pixely in 0 to height-1 {
float yy = (pixely as float)/0.40/height - 1.3
for pixelx in 0 to width-1 {
float xx = (pixelx as float)/0.32/width - 2.2
float xsquared = 0.0
float ysquared = 0.0
float x = 0.0
float y = 0.0
ubyte iter = 0
while iter<max_iter and xsquared+ysquared<4.0 {
y = x*y*2.0 + yy
x = xsquared - ysquared + xx
xsquared = x*x
ysquared = y*y
iter++
}
; txt.setchr(pixelx, pixely, '*')
txt.color2(1, max_iter-iter)
c64.CHROUT(' ')
}
c64.CHROUT('\n')
}
}
}