Select relevant 3D lights per mesh on GLES3 and Mobile renderers

drivers/gles3/rasterizer_scene_gles3.cpp

@@ -71,27 +71,32 @@ uint32_t RasterizerSceneGLES3::geometry_instance_get_pair_mask() {
 	return ((1 << RS::INSTANCE_LIGHT) | (1 << RS::INSTANCE_REFLECTION_PROBE));
 }
 
-void RasterizerSceneGLES3::GeometryInstanceGLES3::pair_light_instances(const RID *p_light_instances, uint32_t p_light_instance_count) {
-	GLES3::Config *config = GLES3::Config::get_singleton();
-
+Pair<uint32_t, uint32_t> RasterizerSceneGLES3::GeometryInstanceGLES3::clear_light_instances() {
 	paired_omni_light_count = 0;
 	paired_spot_light_count = 0;
 	paired_omni_lights.clear();
 	paired_spot_lights.clear();
-
-	for (uint32_t i = 0; i < p_light_instance_count; i++) {
-		RS::LightType type = GLES3::LightStorage::get_singleton()->light_instance_get_type(p_light_instances[i]);
-		switch (type) {
+	return Pair((uint32_t)GLES3::Config::get_singleton()->max_lights_per_object,
+			(uint32_t)GLES3::Config::get_singleton()->max_renderable_lights);
+}
+void RasterizerSceneGLES3::GeometryInstanceGLES3::pair_light_instance(
+		const RID p_light_instance, RS::LightType light_type, uint32_t placement_idx) {
+	if (placement_idx < GLES3::Config::get_singleton()->max_lights_per_object) {
+		switch (light_type) {
 			case RS::LIGHT_OMNI: {
-				if (paired_omni_light_count < (uint32_t)config->max_lights_per_object) {
-					paired_omni_lights.push_back(p_light_instances[i]);
-					paired_omni_light_count++;
+				if (placement_idx >= paired_omni_light_count) {
+					paired_omni_lights.push_back(p_light_instance);
+					++paired_omni_light_count;
+				} else {
+					paired_omni_lights[placement_idx] = p_light_instance;
 				}
 			} break;
 			case RS::LIGHT_SPOT: {
-				if (paired_spot_light_count < (uint32_t)config->max_lights_per_object) {
-					paired_spot_lights.push_back(p_light_instances[i]);
-					paired_spot_light_count++;
+				if (placement_idx >= paired_spot_light_count) {
+					paired_spot_lights.push_back(p_light_instance);
+					++paired_spot_light_count;
+				} else {
+					paired_spot_lights[placement_idx] = p_light_instance;
 				}
 			} break;
 			default:

drivers/gles3/rasterizer_scene_gles3.h

@@ -341,7 +341,8 @@ class RasterizerSceneGLES3 : public RendererSceneRender {
 		virtual void set_use_lightmap(RID p_lightmap_instance, const Rect2 &p_lightmap_uv_scale, int p_lightmap_slice_index) override;
 		virtual void set_lightmap_capture(const Color *p_sh9) override;
 
-		virtual void pair_light_instances(const RID *p_light_instances, uint32_t p_light_instance_count) override;
+		virtual Pair<uint32_t, uint32_t> clear_light_instances() override;
+		virtual void pair_light_instance(const RID p_light_instance, RS::LightType light_type, uint32_t placement_idx) override;
 		virtual void pair_reflection_probe_instances(const RID *p_reflection_probe_instances, uint32_t p_reflection_probe_instance_count) override;
 		virtual void pair_decal_instances(const RID *p_decal_instances, uint32_t p_decal_instance_count) override {}
 		virtual void pair_voxel_gi_instances(const RID *p_voxel_gi_instances, uint32_t p_voxel_gi_instance_count) override {}

servers/rendering/dummy/rasterizer_scene_dummy.h

@@ -66,7 +66,8 @@ class RasterizerSceneDummy : public RendererSceneRender {
 		virtual Transform3D get_transform() override { return Transform3D(); }
 		virtual AABB get_aabb() override { return AABB(); }
 
-		virtual void pair_light_instances(const RID *p_light_instances, uint32_t p_light_instance_count) override {}
+		virtual Pair<uint32_t, uint32_t> clear_light_instances() override { return Pair((uint32_t)0, (uint32_t)0); }
+		virtual void pair_light_instance(const RID p_light_instance, RS::LightType light_type, uint32_t placement_idx) override {}
 		virtual void pair_reflection_probe_instances(const RID *p_reflection_probe_instances, uint32_t p_reflection_probe_instance_count) override {}
 		virtual void pair_decal_instances(const RID *p_decal_instances, uint32_t p_decal_instance_count) override {}
 		virtual void pair_voxel_gi_instances(const RID *p_voxel_gi_instances, uint32_t p_voxel_gi_instance_count) override {}

servers/rendering/renderer_geometry_instance.h

@@ -66,7 +66,8 @@ class RenderGeometryInstance {
 	virtual Transform3D get_transform() = 0;
 	virtual AABB get_aabb() = 0;
 
-	virtual void pair_light_instances(const RID *p_light_instances, uint32_t p_light_instance_count) = 0;
+	virtual Pair<uint32_t, uint32_t> clear_light_instances() = 0;
+	virtual void pair_light_instance(const RID p_light_instance, RS::LightType light_type, uint32_t placement_idx) = 0;
 	virtual void pair_reflection_probe_instances(const RID *p_reflection_probe_instances, uint32_t p_reflection_probe_instance_count) = 0;
 	virtual void pair_decal_instances(const RID *p_decal_instances, uint32_t p_decal_instance_count) = 0;
 	virtual void pair_voxel_gi_instances(const RID *p_voxel_gi_instances, uint32_t p_voxel_gi_instance_count) = 0;

servers/rendering/renderer_rd/forward_clustered/render_forward_clustered.h

@@ -572,7 +572,8 @@ class RenderForwardClustered : public RendererSceneRenderRD {
 		virtual void set_use_lightmap(RID p_lightmap_instance, const Rect2 &p_lightmap_uv_scale, int p_lightmap_slice_index) override;
 		virtual void set_lightmap_capture(const Color *p_sh9) override;
 
-		virtual void pair_light_instances(const RID *p_light_instances, uint32_t p_light_instance_count) override {}
+		virtual Pair<uint32_t, uint32_t> clear_light_instances() override { return Pair((uint32_t)0, (uint32_t)0); }
+		virtual void pair_light_instance(const RID p_light_instance, RS::LightType light_type, uint32_t placement_idx) override {}
 		virtual void pair_reflection_probe_instances(const RID *p_reflection_probe_instances, uint32_t p_reflection_probe_instance_count) override {}
 		virtual void pair_decal_instances(const RID *p_decal_instances, uint32_t p_decal_instance_count) override {}
 		virtual void pair_voxel_gi_instances(const RID *p_voxel_gi_instances, uint32_t p_voxel_gi_instance_count) override;

servers/rendering/renderer_rd/forward_mobile/render_forward_mobile.cpp

@@ -2553,23 +2553,27 @@ uint32_t RenderForwardMobile::geometry_instance_get_pair_mask() {
 	return ((1 << RS::INSTANCE_LIGHT) + (1 << RS::INSTANCE_REFLECTION_PROBE) + (1 << RS::INSTANCE_DECAL));
 }
 
-void RenderForwardMobile::GeometryInstanceForwardMobile::pair_light_instances(const RID *p_light_instances, uint32_t p_light_instance_count) {
+Pair<uint32_t, uint32_t> RenderForwardMobile::GeometryInstanceForwardMobile::clear_light_instances() {
 	omni_light_count = 0;
 	spot_light_count = 0;
-
-	for (uint32_t i = 0; i < p_light_instance_count; i++) {
-		RS::LightType type = RendererRD::LightStorage::get_singleton()->light_instance_get_type(p_light_instances[i]);
-		switch (type) {
+	return Pair((uint32_t)MAX_RDL_CULL,
+			(uint32_t)get_singleton()->get_max_elements());
+}
+void RenderForwardMobile::GeometryInstanceForwardMobile::pair_light_instance(
+		const RID p_light_instance, RS::LightType light_type, uint32_t placement_idx) {
+	if (placement_idx < (uint32_t)MAX_RDL_CULL) {
+		RendererRD::ForwardID light_id = RendererRD::LightStorage::get_singleton()->light_instance_get_forward_id(p_light_instance);
+		switch (light_type) {
 			case RS::LIGHT_OMNI: {
-				if (omni_light_count < (uint32_t)MAX_RDL_CULL) {
-					omni_lights[omni_light_count] = RendererRD::LightStorage::get_singleton()->light_instance_get_forward_id(p_light_instances[i]);
-					omni_light_count++;
+				omni_lights[placement_idx] = light_id;
+				if (placement_idx >= omni_light_count) {
+					omni_light_count = placement_idx + 1;
 				}
 			} break;
 			case RS::LIGHT_SPOT: {
-				if (spot_light_count < (uint32_t)MAX_RDL_CULL) {
-					spot_lights[spot_light_count] = RendererRD::LightStorage::get_singleton()->light_instance_get_forward_id(p_light_instances[i]);
-					spot_light_count++;
+				spot_lights[placement_idx] = light_id;
+				if (placement_idx >= spot_light_count) {
+					spot_light_count = placement_idx + 1;
 				}
 			} break;
 			default:

servers/rendering/renderer_rd/forward_mobile/render_forward_mobile.h

@@ -537,7 +537,8 @@ class RenderForwardMobile : public RendererSceneRenderRD {
 		virtual void set_use_lightmap(RID p_lightmap_instance, const Rect2 &p_lightmap_uv_scale, int p_lightmap_slice_index) override;
 		virtual void set_lightmap_capture(const Color *p_sh9) override;
 
-		virtual void pair_light_instances(const RID *p_light_instances, uint32_t p_light_instance_count) override;
+		virtual Pair<uint32_t, uint32_t> clear_light_instances() override;
+		virtual void pair_light_instance(const RID p_light_instance, RS::LightType light_type, uint32_t placement_idx) override;
 		virtual void pair_reflection_probe_instances(const RID *p_reflection_probe_instances, uint32_t p_reflection_probe_instance_count) override;
 		virtual void pair_decal_instances(const RID *p_decal_instances, uint32_t p_decal_instance_count) override;
 		virtual void pair_voxel_gi_instances(const RID *p_voxel_gi_instances, uint32_t p_voxel_gi_instance_count) override {}

servers/rendering/renderer_scene_cull.cpp

@@ -1956,7 +1956,7 @@ void RendererSceneCull::_unpair_instance(Instance *p_instance) {
 		InstanceGeometryData *geom = static_cast<InstanceGeometryData *>(p_instance->base_data);
 		ERR_FAIL_NULL(geom->geometry_instance);
 
-		geom->geometry_instance->pair_light_instances(nullptr, 0);
+		geom->geometry_instance->clear_light_instances();
 		geom->geometry_instance->pair_reflection_probe_instances(nullptr, 0);
 		geom->geometry_instance->pair_decal_instances(nullptr, 0);
 		geom->geometry_instance->pair_voxel_gi_instances(nullptr, 0);
@@ -2932,26 +2932,83 @@ void RendererSceneCull::_scene_cull(CullData &cull_data, InstanceCullResult &cul
 
 					if (geometry_instance_pair_mask & (1 << RS::INSTANCE_LIGHT) && (idata.flags & InstanceData::FLAG_GEOM_LIGHTING_DIRTY)) {
 						InstanceGeometryData *geom = static_cast<InstanceGeometryData *>(idata.instance->base_data);
-						uint32_t idx = 0;
-
-						for (const Instance *E : geom->lights) {
-							InstanceLightData *light = static_cast<InstanceLightData *>(E->base_data);
-							if (!(RSG::light_storage->light_get_cull_mask(E->base) & idata.layer_mask)) {
-								continue;
-							}
-
-							if ((RSG::light_storage->light_get_bake_mode(E->base) == RS::LIGHT_BAKE_STATIC) && idata.instance->lightmap) {
-								continue;
-							}
-
-							instance_pair_buffer[idx++] = light->instance;
-							if (idx == MAX_INSTANCE_PAIRS) {
-								break;
+						ERR_FAIL_NULL(geom->geometry_instance);
+						// Clear any existing light instances for this mesh and return the max count per-mesh, and total (per-scene).
+						Pair<uint32_t, uint32_t> max_per_mesh_total = geom->geometry_instance->clear_light_instances();
+						if ((max_per_mesh_total.first > 0) && (max_per_mesh_total.second > 0)) {
+							// Run through all M lights, but use a heap to keep track of the best N
+							uint32_t omni_count = 0, spot_count = 0;
+							// Score, index into the light array.
+							LocalVector<Pair<float, uint32_t>> omni_score_idx, spot_score_idx;
+							// SortArray has heap functionality in it.
+							SortArray<Pair<float, uint32_t>> heapify;
+							bool omni_needs_heap = true, spot_needs_heap = true;
+							Vector3 mesh_center = idata.instance->transformed_aabb.get_center();
+							// Run through all lights in the scene (there might be more than max_renderable_lights).
+							uint32_t total_omni_count = 0, total_spot_count = 0;
+							for (const Instance *E : geom->lights) {
+								RS::LightType light_type = RSG::light_storage->light_get_type(E->base);
+								if (((RS::LIGHT_OMNI == light_type) && (total_omni_count++ < max_per_mesh_total.second)) ||
+										((RS::LIGHT_SPOT == light_type) && (total_spot_count++ < max_per_mesh_total.second))) {
+									// Perform culling.
+									if (!(RSG::light_storage->light_get_cull_mask(E->base) & idata.layer_mask)) {
+										continue;
+									}
+									if ((RSG::light_storage->light_get_bake_mode(E->base) == RS::LIGHT_BAKE_STATIC) && idata.instance->lightmap) {
+										continue;
+									}
+
+									InstanceLightData *light = static_cast<InstanceLightData *>(E->base_data);
+									// Large scores are worse, so linear with distance, inverse with energy and range.
+									Vector3 light_center = E->transformed_aabb.get_center();
+									float light_range_energy =
+											RSG::light_storage->light_get_param(E->base, RS::LightParam::LIGHT_PARAM_RANGE) *
+											RSG::light_storage->light_get_param(E->base, RS::LightParam::LIGHT_PARAM_ENERGY);
+									float light_inst_score = mesh_center.distance_to(light_center) / MAX(0.01f, light_range_energy);
+									// Keep the "best" lights on a per-light-type basis.
+									switch (light_type) {
+										case RS::LIGHT_OMNI: {
+											if (omni_count < max_per_mesh_total.first) {
+												// We have room to just add it, and track the score and where it goes.
+												omni_score_idx.push_back(Pair(light_inst_score, omni_count));
+												geom->geometry_instance->pair_light_instance(light->instance, light_type, omni_count++);
+											} else {
+												if (omni_needs_heap) {
+													// We need to make this a heap one time.
+													heapify.make_heap(0, omni_count, &omni_score_idx[0]);
+													omni_needs_heap = false;
+												}
+												if (light_inst_score < omni_score_idx[0].first) {
+													uint32_t replace_index = omni_score_idx[0].second;
+													geom->geometry_instance->pair_light_instance(light->instance, light_type, replace_index);
+													heapify.adjust_heap(0, 0, omni_count, Pair(light_inst_score, replace_index), &omni_score_idx[0]);
+												}
+											}
+										} break;
+										case RS::LIGHT_SPOT: {
+											if (spot_count < max_per_mesh_total.first) {
+												// We have room to just add it, and track the score and where it goes.
+												spot_score_idx.push_back(Pair(light_inst_score, spot_count));
+												geom->geometry_instance->pair_light_instance(light->instance, light_type, spot_count++);
+											} else {
+												if (spot_needs_heap) {
+													// We need to make this a heap one time.
+													heapify.make_heap(0, spot_count, &spot_score_idx[0]);
+													spot_needs_heap = false;
+												}
+												if (light_inst_score < spot_score_idx[0].first) {
+													uint32_t replace_index = spot_score_idx[0].second;
+													geom->geometry_instance->pair_light_instance(light->instance, light_type, replace_index);
+													heapify.adjust_heap(0, 0, spot_count, Pair(light_inst_score, replace_index), &spot_score_idx[0]);
+												}
+											}
+										} break;
+										default:
+											break;
+									}
+								}
 							}
 						}
-
-						ERR_FAIL_NULL(geom->geometry_instance);
-						geom->geometry_instance->pair_light_instances(instance_pair_buffer, idx);
 						idata.flags &= ~InstanceData::FLAG_GEOM_LIGHTING_DIRTY;
 					}