42 lines
544 B
Go
42 lines
544 B
Go
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package main
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import (
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"math"
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)
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func Bresenham2(fb *Framebuffer, color uint, x0 int, y0 int, x1 int, y1 int) {
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dx := int(math.Abs(float64(x1 - x0)))
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sx := -1
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if x0 < x1 {
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sx = 1
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}
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dy := -int(math.Abs(float64(y1 - y0)))
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sy := -1
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if y0 < y1 {
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sy = 1
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}
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err := dx + dy
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for {
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fb.SetSafe(uint(x0), uint(y0), color)
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if x0 == x1 && y0 == y1 {
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break
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}
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e2 := 2 * err
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if e2 >= dy {
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if x0 == x1 {
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break
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}
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err += dy
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x0 += sx
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}
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if e2 <= dx {
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if y0 == y1 {
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break
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}
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err += dx
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y0 += sy
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}
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}
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}
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