Add lighting scene IDs to lighting system

common/src/backend/java/dev/engine_room/flywheel/backend/engine/LightLut.java

@@ -11,46 +11,55 @@
 // Massive kudos to RogueLogix for figuring out this LUT scheme.
 // First layer is Y, then X, then Z.
 public final class LightLut {
-	public final Layer<Layer<IntLayer>> indices = new Layer<>();
+	public final Layer<Layer<Layer<IntLayer>>> indices = new Layer<>();
 
-	public void add(long position, int index) {
+	public void add(int scene, long position, int index) {
 		final var x = SectionPos.x(position);
 		final var y = SectionPos.y(position);
 		final var z = SectionPos.z(position);
 
-		indices.computeIfAbsent(y, Layer::new)
+		indices.computeIfAbsent(scene, Layer::new)
+				.computeIfAbsent(y, Layer::new)
 				.computeIfAbsent(x, IntLayer::new)
 				.set(z, index + 1);
 	}
 
 	public void prune() {
 		// Maybe this could be done better incrementally?
-		indices.prune((middle) -> middle.prune(IntLayer::prune));
+		indices.prune((scene) -> scene.prune((middle) -> middle.prune(IntLayer::prune)));
 	}
 
-	public void remove(long section) {
+	public void remove(int scene, long section) {
 		final var x = SectionPos.x(section);
 		final var y = SectionPos.y(section);
 		final var z = SectionPos.z(section);
 
-		var first = indices.get(y);
+		var first = indices.get(scene);
 
 		if (first == null) {
 			return;
 		}
 
-		var second = first.get(x);
+		var second = first.get(y);
 
 		if (second == null) {
 			return;
 		}
 
-		second.clear(z);
+		var third = second.get(x);
+
+		if (third == null) {
+			return;
+		}
+
+		third.clear(z);
 	}
 
 	public IntArrayList flatten() {
 		final var out = new IntArrayList();
-		indices.fillLut(out, (yIndices, lut) -> yIndices.fillLut(lut, IntLayer::fillLut));
+		this.indices.fillLut(out, (sceneIndices, lut1) -> sceneIndices.fillLut(lut1,
+				(yIndices, lut2) -> yIndices.fillLut(lut2, IntLayer::fillLut)
+		));
 		return out;
 	}
 

common/src/backend/java/dev/engine_room/flywheel/backend/engine/LightStorage.java

@@ -195,12 +195,12 @@ private void removeUnusedSections() {
 	}
 
 	private void beginTrackingSection(long section, int index) {
-		lut.add(section, index);
+		lut.add(0, section, index);
 		needsLutRebuild = true;
 	}
 
 	private void endTrackingSection(long section) {
-		lut.remove(section);
+		lut.remove(0, section);
 		needsLutRebuild = true;
 	}
 

common/src/backend/resources/assets/flywheel/flywheel/internal/api_impl.glsl

@@ -3,10 +3,10 @@ struct FlwLightAo {
     float ao;
 };
 
-/// Get the light at the given world position relative to flw_renderOrigin from the given normal.
+/// Get the light at the given scene and world position relative to flw_renderOrigin from the given normal.
 /// This may be interpolated for smooth lighting.
-bool flw_light(vec3 worldPos, vec3 normal, out FlwLightAo light);
+bool flw_light(uint scene, vec3 worldPos, vec3 normal, out FlwLightAo light);
 
-/// Fetches the light value at the given block position.
+/// Fetches the light value at the given scene and block position.
 /// Returns false if the light for the given block is not available.
-bool flw_lightFetch(ivec3 blockPos, out vec2 light);
+bool flw_lightFetch(uint scene, ivec3 blockPos, out vec2 light);

common/src/backend/resources/assets/flywheel/flywheel/internal/light_lut.glsl

@@ -44,9 +44,14 @@ bool _flw_nextLut(uint base, int coord, out uint next) {
     return false;
 }
 
-bool _flw_chunkCoordToSectionIndex(ivec3 sectionPos, out uint index) {
+bool _flw_chunkCoordToSectionIndex(uint sceneId, ivec3 sectionPos, out uint index) {
+    uint scene;
+    if (_flw_nextLut(0u, int(sceneId), scene) || scene == 0u) {
+        return true;
+    }
+
     uint first;
-    if (_flw_nextLut(0u, sectionPos.y, first) || first == 0u) {
+    if (_flw_nextLut(scene, sectionPos.y, first) || first == 0u) {
         return true;
     }
 
@@ -90,9 +95,9 @@ bool _flw_isSolid(uint sectionOffset, uvec3 blockInSectionPos) {
     return (word & (1u << bitInWordOffset)) != 0u;
 }
 
-bool flw_lightFetch(ivec3 blockPos, out vec2 lightCoord) {
+bool flw_lightFetch(uint scene, ivec3 blockPos, out vec2 lightCoord) {
     uint lightSectionIndex;
-    if (_flw_chunkCoordToSectionIndex(blockPos >> 4, lightSectionIndex)) {
+    if (_flw_chunkCoordToSectionIndex(scene, blockPos >> 4, lightSectionIndex)) {
         return false;
     }
     // The offset of the section in the light buffer.
@@ -307,14 +312,14 @@ vec3 _flw_lightForDirection(uint[27] lights, vec3 interpolant, uint c00, uint c0
     return light;
 }
 
-bool flw_light(vec3 worldPos, vec3 normal, out FlwLightAo light) {
+bool flw_light(uint scene, vec3 worldPos, vec3 normal, out FlwLightAo light) {
     // Always use the section of the block we are contained in to ensure accuracy.
     // We don't want to interpolate between sections, but also we might not be able
     // to rely on the existence neighboring sections, so don't do any extra rounding here.
     ivec3 blockPos = ivec3(floor(worldPos)) + flw_renderOrigin;
 
     uint lightSectionIndex;
-    if (_flw_chunkCoordToSectionIndex(blockPos >> 4, lightSectionIndex)) {
+    if (_flw_chunkCoordToSectionIndex(scene, blockPos >> 4, lightSectionIndex)) {
         return false;
     }
     // The offset of the section in the light buffer.

common/src/lib/resources/assets/flywheel/flywheel/light/flat.glsl

@@ -1,6 +1,6 @@
 void flw_shaderLight() {
     vec2 embeddedLight;
-    if (flw_lightFetch(ivec3(floor(flw_vertexPos.xyz)) + flw_renderOrigin, embeddedLight)) {
+    if (flw_lightFetch(0, ivec3(floor(flw_vertexPos.xyz)) + flw_renderOrigin, embeddedLight)) {
         flw_fragLight = max(flw_fragLight, embeddedLight);
     }
 }

common/src/lib/resources/assets/flywheel/flywheel/light/smooth.glsl

@@ -1,6 +1,6 @@
 void flw_shaderLight() {
     FlwLightAo light;
-    if (flw_light(flw_vertexPos.xyz, flw_vertexNormal, light)) {
+    if (flw_light(0, flw_vertexPos.xyz, flw_vertexNormal, light)) {
         flw_fragLight = max(flw_fragLight, light.light);
 
         flw_fragColor.rgb *= light.ao;

common/src/lib/resources/assets/flywheel/flywheel/light/smooth_when_embedded.glsl

@@ -1,7 +1,7 @@
 void flw_shaderLight() {
     #ifdef FLW_EMBEDDED
     FlwLightAo light;
-    if (flw_light(flw_vertexPos.xyz, flw_vertexNormal, light)) {
+    if (flw_light(0, flw_vertexPos.xyz, flw_vertexNormal, light)) {
         flw_fragLight = max(flw_fragLight, light.light);
 
         flw_fragColor.rgb *= light.ao;

docs/shader-api/common.glsl

@@ -3,10 +3,10 @@ struct FlwLightAo {
     float ao;
 };
 
-/// Get the light at the given world position.
+/// Get the light at the given scene and world position.
 /// This may be interpolated for smooth lighting.
-bool flw_light(vec3 worldPos, vec3 normal, out FlwLightAo light);
+bool flw_light(uint scene, vec3 worldPos, vec3 normal, out FlwLightAo light);
 
-/// Fetches the light value at the given block position.
+/// Fetches the light value at the given scene and block position.
 /// Returns false if the light for the given block is not available.
-bool flw_lightFetch(ivec3 blockPos, out vec2 light);
+bool flw_lightFetch(uint scene, ivec3 blockPos, out vec2 light);