Files
sumi/sierpinski.go

48 lines
1.2 KiB
Go

package main
import (
rl "github.com/gen2brain/raylib-go/raylib"
)
type SierpinskiArrow struct {
dirty bool
}
func (s *SierpinskiArrow) Draw(env *Env) {
rl.Translatef(float32(env.GetGraphicsWidth())/2.0, float32(env.GetGraphicsHeight())/2.0, 0)
rl.ClearBackground(rl.NewColor(0, 0, 0, 0))
sierpinskiArrow(env, int(env.Ports["sierpinskiArrowDepth"]), env.Ports["sierpinskiArrowLength"])
}
func (s *SierpinskiArrow) Update(_ *Env) {
s.dirty = true
}
func (s *SierpinskiArrow) IsDirty() bool {
return s.dirty
}
func sierpinskiArrow(env *Env, order int, length float64) {
if order == 0 {
curve(env, order, length, env.Ports["sierpinskiArrowAngle"])
} else {
rl.Rotatef(float32(env.Ports["sierpinskiArrowAngle"]), 0, 0, 1)
curve(env, order, length, -env.Ports["sierpinskiArrowAngle"])
}
}
func curve(env *Env, order int, length float64, angle float64) {
if order == 0 {
len := int32(length)
rl.SetLineWidth(4)
rl.DrawLine(0, 0, len, 0, rl.RayWhite)
rl.Translatef(float32(length), 0, 0)
} else {
curve(env, order-1, length/2, -angle)
rl.Rotatef(float32(angle), 0, 0, 1)
curve(env, order-1, length/2, angle)
rl.Rotatef(float32(angle), 0, 0, 1)
curve(env, order-1, length/2, -angle)
}
}