# demo1.py
# draw a series of rotated trianges with different colors and different transparencies

import PyArt,math

ident = [1, 0, 0, 1, 0, 0]

canvas = PyArt.Canvas(256,156, bg=0x7f7f7f) 
canvas.gstate.fill = 0x0000FF
canvas.gstate.fill_opacity = .5

# define the triangle path p
p = PyArt.Path()
yu = 36.95
p.moveto(0,-yu)
p.lineto(-32,yu/2.0)
p.lineto(32,yu/2.0)
p.close()
p.end()

# paint the first triangle
x0,y0  = 96, 96
sc = 2.0
canvas.translate(x0,y0)
canvas.scale(sc,sc)
canvas.fill(p)

# paint the second triangle, rotating & scaling relative to the first
canvas.gstate.CTM = ident
canvas.translate(x0+32,y0)
canvas.rotate(35)
sc = sc/math.sqrt(3.0)
canvas.scale(sc,sc)

canvas.gstate.fill = 0x00FF00 # green
canvas.fill(p)


# paint the next triangle
canvas.gstate.CTM = ident

canvas.translate(x0+32*2,y0)
canvas.rotate(35*2)
sc = sc/math.sqrt(3.0)
canvas.scale(sc,sc)
canvas.gstate.fill = 0xFF0000 # red
canvas.gstate.fill_opacity = canvas.gstate.fill_opacity/2.0
canvas.fill(p)

# last triangle
canvas.gstate.CTM = ident
canvas.translate(x0+32*2.5,y0)
canvas.rotate(35*3)
sc = sc/math.sqrt(3.0)
canvas.scale(sc,sc)
canvas.gstate.fill = 0x00FFFF 
canvas.gstate.fill_opacity = canvas.gstate.fill_opacity/2.0
canvas.fill(p)

canvas.save("demo1.png")