//go:build ignore

//kage:unit pixels

package main

var Time float

func Fragment(dstPos vec4, srcPos vec2, color vec4) vec4 {
	orig := imageSrc0At(srcPos)
	if orig.a < 0.01 {
		return orig
	}

	// Flame noise using position and time
	noise := fract(sin(dot(srcPos, vec2(12.9898, 78.233))) * 43758.5453)
	noise2 := fract(sin(dot(srcPos*0.5, vec2(45.123, 67.89))) * 12345.6789)
	noiseTime := fract(sin(dot(srcPos + Time*0.1, vec2(98.765, 43.21))) * 54321.9876)

	// Moving flame pattern
	flame := sin(srcPos.x*10.0 + Time*3.0) * cos(srcPos.y*8.0 - Time*2.5)
	flame2 := sin((srcPos.x*15.0 + srcPos.y*12.0) + Time*4.0)
	flamePattern := flame * 0.5 + flame2 * 0.5

	// Combine noise and flame
	burnIntensity := (noise*0.3 + noise2*0.3 + noiseTime*0.2 + flamePattern*0.2)
	burnIntensity = clamp(burnIntensity, 0.0, 1.0)

	// Warm color palette
	r := 1.0
	g := burnIntensity * 0.6 + 0.2
	b := burnIntensity * 0.1

	// Alpha
	a := orig.a

	// Edge glowing effect
	edgeGlow := abs(sin(srcPos.x*20.0 + srcPos.y*15.0 + Time*5.0)) * 0.3

	return vec4(
		min(r + edgeGlow, 1.0),
		min(g + edgeGlow*0.5, 1.0),
		min(b + edgeGlow*0.2, 1.0),
		a,
	)
}