52 lines
1.3 KiB
Go
52 lines
1.3 KiB
Go
package main
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import (
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"fmt"
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rl "github.com/gen2brain/raylib-go/raylib"
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)
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type SierpinskiArrow struct{
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dirty bool
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}
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func (s *SierpinskiArrow) Draw(ctx *RenderCtx) {
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rl.Translatef(float32(ctx.SourceWidth) / 2.0, float32(ctx.SourceHeight) / 2.0, 0)
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rl.ClearBackground(rl.NewColor(0, 0, 0, 0))
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sierpinskiArrow(ctx, int(ctx.Ports["sierpinskiArrowDepth"]), ctx.Ports["sierpinskiArrowLength"])
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}
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func (s *SierpinskiArrow) Update(ctx *RenderCtx) {
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s.dirty = true
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}
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func (s *SierpinskiArrow) IsDirty() bool {
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return s.dirty
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}
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func sierpinskiArrow(ctx *RenderCtx, order int, length float64) {
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fmt.Printf("drawing SierpinskiArrow, order = %d, length = %.2f\n", order, length)
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if order == 0 {
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curve(ctx, order, length, ctx.Ports["sierpinskiArrowAngle"])
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} else {
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rl.Rotatef(float32(ctx.Ports["sierpinskiArrowAngle"]), 0, 0, 1)
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curve(ctx, order, length, -ctx.Ports["sierpinskiArrowAngle"])
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}
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}
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func curve(ctx *RenderCtx, order int, length float64, angle float64) {
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if order == 0 {
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len := int32(length)
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rl.SetLineWidth(4)
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rl.DrawLine(0, 0, len, 0, rl.RayWhite)
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rl.Translatef(float32(length), 0, 0)
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} else {
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curve(ctx, order-1, length/2, -angle)
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rl.Rotatef(float32(angle), 0, 0, 1)
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curve(ctx, order-1, length/2, angle)
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rl.Rotatef(float32(angle), 0, 0, 1)
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curve(ctx, order-1, length/2, -angle)
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}
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}
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