59 lines
1.1 KiB
Go
59 lines
1.1 KiB
Go
package main
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import (
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"fmt"
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"github.com/ungerik/go3d/vec3"
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"log"
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"strings"
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"time"
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)
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// Clamp a float value to the given range
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func fclamp(val float32, minval int, maxval int) int {
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return max(minval, min(maxval, int(val)))
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}
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func main() {
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log.Printf("Program begin")
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const (
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width = 1024
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height = 768
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colmax = 255
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)
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framebuffer := make([]vec3.T, width*height)
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now := time.Now()
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for y := range height {
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for x := range width {
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framebuffer[x+y*width] = vec3.T{
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float32(y) / float32(height),
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float32(x) / float32(width),
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0,
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}
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}
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}
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log.Printf("Generate frame took %dms", time.Since(now).Milliseconds())
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fmt.Printf("P3\n%d %d\n%d\n# Image contents\n", width, height, colmax)
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var buffer strings.Builder
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now = time.Now()
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for i := range height * width {
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fb := framebuffer[i]
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buffer.WriteString(fmt.Sprintf("%d %d %d\t",
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fclamp(colmax*fb[0], 0, colmax),
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fclamp(colmax*fb[1], 0, colmax),
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fclamp(colmax*fb[2], 0, colmax),
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))
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if i&63 == 63 {
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buffer.WriteRune('\n')
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}
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}
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log.Printf("Conversion took %dms", time.Since(now).Milliseconds())
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fmt.Printf(buffer.String())
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fmt.Printf("\n# Image end\n")
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}
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