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

shaders/Lib/BasicFunctions/Blocklight.glsl

@@ -0,0 +1,37 @@
+// MinecraftPT — Block Light
+// Maps vanilla block light level to physical light, with per-block colors.
+
+#ifndef BLOCKLIGHT_GLSL
+#define BLOCKLIGHT_GLSL
+
+// Convert lightmap blocklight (0-1) to physical light intensity
+float BlocklightFromLightmap(float blocklight){
+	return pow(blocklight, 2.0) * BLOCKLIGHT_BRIGHTNESS;
+}
+
+// Get the block light color for a material
+vec3 BlocklightColor(float materialID){
+	// Warm torch color by default
+	vec3 color = pow(vec3(COLOR_TORCH_R, COLOR_TORCH_G, COLOR_TORCH_B), vec3(2.2));
+
+	if (materialID == MATID_SOULTORCH || materialID == MATID_COPPER_LANTERN){
+		color = pow(vec3(COLOR_SOULTORCH_R, COLOR_SOULTORCH_G, COLOR_SOULTORCH_B), vec3(2.2));
+	}else if (materialID == MATID_AMETHYST){
+		color = pow(vec3(COLOR_AMETHYST_R, COLOR_AMETHYST_G, COLOR_AMETHYST_B), vec3(2.2));
+	}else if (materialID == MATID_FIRE){
+		color = pow(vec3(COLOR_FIRE_R, COLOR_FIRE_G, COLOR_FIRE_B), vec3(2.2));
+	}else if (materialID == MATID_ENDROD){
+		color = pow(vec3(COLOR_ENDROD_R, COLOR_ENDROD_G, COLOR_ENDROD_B), vec3(2.2));
+	}
+
+	return color * BlocklightFromLightmap(0.5);
+}
+
+// Physical block light for a lightmap value
+vec3 Blocklight(vec2 lightmap){
+	// Blocklight color temperature
+	vec3 warmColor = pow(vec3(COLOR_TORCH_R, COLOR_TORCH_G, COLOR_TORCH_B), vec3(2.2));
+	return warmColor * pow(lightmap.x, 2.0) * BLOCKLIGHT_BRIGHTNESS;
+}
+
+#endif