2023-01-16 19:10:47 +01:00

96 lines
2.3 KiB
Go

package main
import (
"image"
"image/color"
"image/draw"
"log"
"math/rand"
"time"
"github.com/zserge/fenster"
)
type Fire struct {
*image.Paletted
}
var palette = color.Palette{
color.RGBA{0x07, 0x07, 0x07, 0xff},
color.RGBA{0x1f, 0x07, 0x07, 0xff},
color.RGBA{0x2f, 0x0f, 0x07, 0xff},
color.RGBA{0x47, 0x0f, 0x07, 0xff},
color.RGBA{0x57, 0x17, 0x07, 0xff},
color.RGBA{0x67, 0x1f, 0x07, 0xff},
color.RGBA{0x77, 0x1f, 0x07, 0xff},
color.RGBA{0x8f, 0x27, 0x07, 0xff},
color.RGBA{0x9f, 0x2f, 0x07, 0xff},
color.RGBA{0xaf, 0x3f, 0x07, 0xff},
color.RGBA{0xbf, 0x47, 0x07, 0xff},
color.RGBA{0xc7, 0x47, 0x07, 0xff},
color.RGBA{0xdf, 0x4f, 0x07, 0xff},
color.RGBA{0xdf, 0x57, 0x07, 0xff},
color.RGBA{0xdf, 0x57, 0x07, 0xff},
color.RGBA{0xd7, 0x5f, 0x07, 0xff},
color.RGBA{0xd7, 0x67, 0x0f, 0xff},
color.RGBA{0xcf, 0x6f, 0x0f, 0xff},
color.RGBA{0xcf, 0x77, 0x0f, 0xff},
color.RGBA{0xcf, 0x7f, 0x0f, 0xff},
color.RGBA{0xcf, 0x87, 0x17, 0xff},
color.RGBA{0xc7, 0x87, 0x17, 0xff},
color.RGBA{0xc7, 0x8f, 0x17, 0xff},
color.RGBA{0xc7, 0x97, 0x1f, 0xff},
color.RGBA{0xbf, 0x9f, 0x1f, 0xff},
color.RGBA{0xbf, 0x9f, 0x1f, 0xff},
color.RGBA{0xbf, 0xa7, 0x27, 0xff},
color.RGBA{0xbf, 0xa7, 0x27, 0xff},
color.RGBA{0xbf, 0xaf, 0x2f, 0xff},
color.RGBA{0xb7, 0xaf, 0x2f, 0xff},
color.RGBA{0xb7, 0xb7, 0x2f, 0xff},
color.RGBA{0xb7, 0xb7, 0x37, 0xff},
color.RGBA{0xcf, 0xcf, 0x6f, 0xff},
color.RGBA{0xdf, 0xdf, 0x9f, 0xff},
color.RGBA{0xef, 0xef, 0xc7, 0xff},
color.RGBA{0xff, 0xff, 0xff, 0xff},
}
func newFire(r image.Rectangle, p color.Palette) *Fire {
img := image.NewPaletted(r, p)
b := r.Bounds().Max
// seed
for x := 0; x < b.X; x++ {
img.SetColorIndex(x, b.Y-1, uint8(len(palette)-1))
}
return &Fire{Paletted: img}
}
func (f *Fire) Next() {
b := f.Bounds().Max
for x := 0; x < b.X; x++ {
for y := b.Y - 1; y > 0; y-- {
z := rand.Intn(3) - 1 // -1, 0, 1
n := f.ColorIndexAt(x, y)
if n > 0 && z == 0 {
n-- // next color
}
f.SetColorIndex(x+z, y-1, n)
}
}
}
func main() {
win, err := fenster.New(320, 200, "Doom Fire")
if err != nil {
log.Fatal(err)
}
defer win.Close()
f := newFire(win.Bounds(), palette)
for win.Loop(time.Second / 60) {
if win.Key(27) || win.Key('Q') {
break
}
f.Next()
draw.Draw(win, win.Bounds(), f, image.Point{}, draw.Src)
}
}