Initial commit: Minecraft 光追着色器包（从零实现的 path tracing）

2026-09-19 12:06:22 +08:00
commit 59e30822f8
314 changed files with 9259 additions and 0 deletions
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+// MinecraftPT — Translucent_FS
+// Composites translucent geometry (water, glass, particles) on top of solid.
+
+#include "/Lib/Settings.glsl"
+#include "/Lib/Utilities.glsl"
+#include "/Lib/BasicFunctions/LightingConstants.glsl"
+#include "/Lib/GbufferData.glsl"
+#include "/Lib/BasicFunctions/Sunlight_Shadow.glsl"
+#include "/Lib/BasicFunctions/Blocklight.glsl"
+#include "/Lib/PathTracing/Tracer/SampleIRC.glsl"
+#include "/Lib/PathTracing/Tracer/ShadowTracing.glsl"
+
+uniform sampler2D colortex12; // combined HDR solid scene
+uniform sampler2D colortex4;  // translucent albedo
+uniform sampler2D colortex5;  // translucent normal
+
+layout(location = 0) out vec4 colorOut;
+
+void main(){
+	ivec2 texelCoord = ivec2(gl_FragCoord.xy);
+
+	float depth = texelFetch(depthtex0, texelCoord, 0).r;
+	if (depth >= 1.0){
+		colorOut = texelFetch(colortex12, texelCoord, 0);
+		return;
+	}
+
+	// Check if there is translucent data
+	vec4 gbuffer5 = texelFetch(colortex5, texelCoord, 0);
+	float matID = gbuffer5.a * 255.0;
+
+	if (matID < 0.5){
+		colorOut = texelFetch(colortex12, texelCoord, 0);
+		return;
+	}
+
+	bool isSmooth;
+	GbufferData gbuffer = GetGbufferDataTranslucent(texelCoord, isSmooth);
+
+	vec4 viewPos = gbufferProjectionInverse * vec4(vec2(texelCoord) / screenSize * 2.0 - 1.0, depth * 2.0 - 1.0, 1.0);
+	viewPos.xyz /= viewPos.w;
+	vec3 worldPos = gbufferModelViewInverse[3].xyz + viewPos.xyz;
+
+	vec3 solidColor = texelFetch(colortex12, texelCoord, 0).rgb;
+
+	// Water: blend with refraction
+	vec3 color = solidColor;
+
+	if (matID == MATID_WATER){
+		vec3 waterColor = gbuffer.albedo;
+		float alpha = gbuffer.albedoAlpha;
+
+		// Fresnel
+		vec3 viewDir = normalize(-viewPos.xyz);
+		float NdotV = max(dot(gbuffer.worldNormal, viewDir), 0.0);
+		float fresnel = 0.02 + 0.98 * pow(1.0 - NdotV, 5.0);
+
+		// Light contribution (sun + sky) on water
+		vec3 sunLight = GetSunlight(viewPos.xyz, worldPos, gbuffer.vertexNormal, gbuffer.worldNormal, gbuffer.lightmap.x);
+		vec3 waterLight = waterColor * (sunLight + Blocklight(gbuffer.lightmap) * 0.5);
+
+		// Water tint / depth color
+		vec3 deepColor = waterColor * 0.3;
+
+		color = mix(solidColor, waterLight + deepColor, fresnel * 0.8 + 0.2);
+
+	}else if (matID == MATID_STAINEDGLASS){
+		vec3 glassColor = gbuffer.albedo;
+		float alpha = gbuffer.albedoAlpha;
+
+		vec3 viewDir = normalize(-viewPos.xyz);
+		float NdotV = max(dot(gbuffer.worldNormal, viewDir), 0.0);
+		float fresnel = 0.04 + 0.96 * pow(1.0 - NdotV, 5.0);
+
+		color = mix(solidColor, solidColor * glassColor, fresnel);
+		color += glassColor * 0.1;
+
+	}else{
+		// Particles etc — additively blend
+		color = solidColor + gbuffer.albedo * gbuffer.albedoAlpha * 0.5;
+	}
+
+	colorOut = vec4(color, 1.0);
+}