// MinecraftPT — TAA
// Temporal anti-aliasing with jittered accumulation and neighborhood clamping.

#include "/Lib/Settings.glsl"
#include "/Lib/Utilities.glsl"
#include "/Lib/BasicFunctions/TemporalNoise.glsl"

uniform sampler2D colortex12; // HDR scene (current)
uniform sampler2D colortex13; // previous frame HDR

layout(location = 0) out vec4 colorOut;
layout(location = 1) out vec4 historyOut; // same result, stored for next frame

void main(){
	vec2 texelCoord = gl_FragCoord.xy;

	vec3 current = texelFetch(colortex12, ivec2(texelCoord), 0).rgb;

	// Motion vector
	vec2 motion = texelFetch(colortex10, ivec2(texelCoord * 0.5), 0).xy * 2.0;
	vec2 prevCoord = texelCoord + motion;

	// Sample previous
	vec3 history = textureLod(colortex13, prevCoord / screenSize, 0.0).rgb;

	// Neighborhood clamp
	vec3 minColor = history;
	vec3 maxColor = history;
	for (int i = -1; i <= 1; i++){
	for (int j = -1; j <= 1; j++){
		vec3 c = textureLod(colortex13, (prevCoord + vec2(i, j)) / screenSize, 0.0).rgb;
		minColor = min(minColor, c);
		maxColor = max(maxColor, c);
	}}
	history = clamp(history, minColor, maxColor);

	// Subpixel sharpening
	float sharpening = TAA_SUBPIXEL_SHARPNING;
	current = current + (current - history) * sharpening * TAA_AGGRESSION;

	float blend = TAA_BLENDWEIGHT;
	vec3 color = mix(current, history, blend);

	colorOut = vec4(color, 1.0);
	historyOut = vec4(color, 1.0);
}