ReSTIR (with tweaks)

baseq2/q2rtx.menu

@@ -147,6 +147,7 @@ begin video
         toggle "AMD FSR 1.0" flt_fsr_enable
         range --status "lower is sharper" "AMD FSR 1.0 sharpness" flt_fsr_sharpness 0 2 0.01
         pairs "global illumination" pt_num_bounce_rays low 0.5 medium 1 high 2
+        pairs "direct light sampling" pt_restir "RIS light" 0 "ReSTIR, high quality" 1 "ReSTIR, half" 2 "ReSTIR, quarter" 3
         pairs "reflection/refraction depth" pt_reflect_refract off 0 1 1 2 2 4 4 8 8
 		toggle --status "turn some monitors in the game into security camera views" \
             "security cameras" pt_cameras

cmake/compileShaders.cmake

@@ -16,6 +16,7 @@ set(SHADER_SOURCE_DEPENDENCIES
     ${CMAKE_SOURCE_DIR}/src/refresh/vkpt/shader/precomputed_sky.glsl
     ${CMAKE_SOURCE_DIR}/src/refresh/vkpt/shader/precomputed_sky_params.h
     ${CMAKE_SOURCE_DIR}/src/refresh/vkpt/shader/projection.glsl
+    ${CMAKE_SOURCE_DIR}/src/refresh/vkpt/shader/restir.h
     ${CMAKE_SOURCE_DIR}/src/refresh/vkpt/shader/sky.h
     ${CMAKE_SOURCE_DIR}/src/refresh/vkpt/shader/tiny_encryption_algorithm.h
     ${CMAKE_SOURCE_DIR}/src/refresh/vkpt/shader/tone_mapping_utils.glsl

doc/client.md

@@ -937,6 +937,13 @@ Selects the projection to use for rendering. Default value is 0.
 #### `pt_reflect_refract`
 Number of reflection or refraction bounces to trace. Default value is 2.
 
+#### `pt_restir`
+Switch for experimental direct light sampling algorithms. Default value is 1.
+- 0 — RIS light sampling.
+- 1 — ReSTIR, high quality.
+- 2 — ReSTIR El-Cheapo, uses half of the shadow rays.
+- 3 — ReSTIR El-Very-Cheapo, uses one quarter of the shadow rays.
+
 #### `pt_roughness_override`
 Global override for roughness of all materials. Negative values mean there is no
 override. Default value is -1.

inc/refresh/models.h

@@ -118,6 +118,7 @@ typedef struct light_poly_s {
 	int cluster;
 	int style;
 	float emissive_factor;
+	int type;
 } light_poly_t;
 
 typedef struct maliasmesh_s maliasmesh_t;

src/refresh/vkpt/bsp_mesh.c

@@ -959,6 +959,7 @@ collect_one_light_poly_entire_texture(bsp_t *bsp, mface_t *surf, mtexinfo_t *tex
 
 		light.material = texinfo->material;
 		light.style = light_style;
+		light.type = LIGHT_POLYGON;
 
 		if(!get_triangle_off_center(light.positions, light.off_center, NULL, 1.f))
 			continue;
@@ -1113,6 +1114,7 @@ collect_one_light_poly(bsp_t *bsp, mface_t *surf, mtexinfo_t *texinfo, int model
 				light_poly_t* light = append_light_poly(num_lights, allocated_lights, lights);
 				light->material = texinfo->material;
 				light->style = light_style;
+				light->type = LIGHT_POLYGON;
 				light->emissive_factor = emissive_factor;
 				VectorCopy(instance_positions[0], light->positions + 0);
 				VectorCopy(instance_positions[i1], light->positions + 3);
@@ -1328,6 +1330,7 @@ collect_sky_and_lava_light_polys(bsp_mesh_t *wm, bsp_t* bsp)
 			}
 
 			light.style = 0;
+			light.type = LIGHT_POLYGON;
 
 			if (!get_triangle_off_center(light.positions, light.off_center, NULL, 1.f))
 				continue;
@@ -1821,6 +1824,7 @@ bsp_mesh_create_custom_sky_prims(uint32_t* prim_ctr, bsp_mesh_t* wm, const bsp_t
 		light->material = 0;
 		light->style = 0;
 		light->cluster = cluster;
+		light->type = LIGHT_POLYGON;
 
 		++*prim_ctr;
 

src/refresh/vkpt/conversion.h

@@ -90,6 +90,16 @@ static inline float halfToFloat(uint16_t value)
 	return v.f;
 }
 
+static inline float uintBitsToFloat(uint32_t ui)
+{
+	union {
+		float f;
+		uint32_t ui;
+	} bits;
+	bits.ui = ui;
+	return bits.f;
+}
+
 void packHalf4x16(uint32_t* half, float* vec4);
 
 #endif // CONVERSION_H_

src/refresh/vkpt/main.c

@@ -1666,20 +1666,14 @@ destroy_vulkan(void)
 	return 0;
 }
 
-typedef struct entity_hash_s {
-	unsigned int mesh : 8;
-	unsigned int model : 9;
-	unsigned int entity : 14;
-	unsigned int bsp : 1;
-} entity_hash_t;
-
 static int entity_frame_num = 0;
 static uint32_t model_entity_ids[2][MAX_MODEL_INSTANCES];
 static int model_entity_id_count[2];
+static int light_entity_ids[2][MAX_MODEL_LIGHTS];
+static int light_entity_id_count[2];
 static int iqm_matrix_count[2];
 static ModelInstance model_instances_prev[MAX_MODEL_INSTANCES];
 
-#define MAX_MODEL_LIGHTS 16384
 static int num_model_lights = 0;
 static light_poly_t model_lights[MAX_MODEL_LIGHTS];
 
@@ -1808,47 +1802,70 @@ static void fill_model_instance(ModelInstance* instance, const entity_t* entity,
 		instance->material |= MATERIAL_FLAG_LIGHT;
 }
 
-static void add_dlight_spot(const dlight_t* light, DynLightData* dynlight_data)
+static void add_dlight_spot(const dlight_t* dlight, light_poly_t* light)
 {
 	// Copy spot data
-	VectorCopy(light->spot.direction, dynlight_data->spot_direction);
-	switch(light->spot.emission_profile)
+	VectorCopy(dlight->spot.direction, light->positions + 6);
+	uint spot_type = 0, spot_data = 0;
+	switch(dlight->spot.emission_profile)
 	{
 	case DLIGHT_SPOT_EMISSION_PROFILE_FALLOFF:
-		dynlight_data->type |= DYNLIGHT_SPOT_EMISSION_PROFILE_FALLOFF << 16;
-		dynlight_data->spot_data = floatToHalf(light->spot.cos_total_width) | (floatToHalf(light->spot.cos_falloff_start) << 16);
+		spot_type = DYNLIGHT_SPOT_EMISSION_PROFILE_FALLOFF;
+		spot_data = floatToHalf(dlight->spot.cos_total_width) | (floatToHalf(dlight->spot.cos_falloff_start) << 16);
 		break;
 	case DLIGHT_SPOT_EMISSION_PROFILE_AXIS_ANGLE_TEXTURE:
-		dynlight_data->type |= DYNLIGHT_SPOT_EMISSION_PROFILE_AXIS_ANGLE_TEXTURE << 16;
-		dynlight_data->spot_data = floatToHalf(light->spot.total_width) | (light->spot.texture << 16);
+		spot_type = DYNLIGHT_SPOT_EMISSION_PROFILE_AXIS_ANGLE_TEXTURE;
+		spot_data = floatToHalf(dlight->spot.total_width) | (dlight->spot.texture << 16);
 		break;
 	}
+	light->positions[4] = uintBitsToFloat(spot_type);
+	light->positions[5] = uintBitsToFloat(spot_data);
 }
 
 static void
-add_dlights(const dlight_t* lights, int num_lights, QVKUniformBuffer_t* ubo)
+add_dlights(const dlight_t* dlights, int num_dlights, light_poly_t* light_list, int* num_lights, int max_lights, bsp_t *bsp, int* light_entity_ids)
 {
-	ubo->num_dyn_lights = 0;
-
-	for (int i = 0; i < num_lights; i++)
+	for (int i = 0; i < num_dlights; i++)
 	{
-		const dlight_t* light = lights + i;
-
-		DynLightData* dynlight_data = ubo->dyn_light_data + ubo->num_dyn_lights;
-		VectorCopy(light->origin, dynlight_data->center);
-		VectorScale(light->color, light->intensity / 25.f, dynlight_data->color);
-		dynlight_data->radius = light->radius;
-		switch(light->light_type) {
-		case DLIGHT_SPHERE:
-			dynlight_data->type = DYNLIGHT_SPHERE;
-			break;
-		case DLIGHT_SPOT:
-			dynlight_data->type = DYNLIGHT_SPOT;
-			add_dlight_spot(light, dynlight_data);
-			break;
-		}
+		if (*num_lights >= max_lights)
+			return;
+
+		const dlight_t* dlight = dlights + i;
+		light_poly_t* light = light_list + *num_lights;
 
-		ubo->num_dyn_lights++;
+		light->cluster = BSP_PointLeaf(bsp->nodes, dlight->origin)->cluster;
+
+		entity_hash_t hash;
+		hash.entity = i + 1; //entity ID
+		hash.mesh = 0xAA;
+
+		if(light->cluster >= 0)
+		{
+			//Super wasteful but we want to have all lights in the same list.
+
+			VectorCopy(dlight->origin, light->positions + 0);
+			VectorScale(dlight->color, dlight->intensity / 25.f, light->color);
+			light->positions[3] = dlight->radius;
+			light->material = NULL;
+			light->style = 0;
+
+			switch(dlight->light_type) {
+				case DLIGHT_SPHERE:
+					light->type = LIGHT_SPHERE;
+					hash.model = 0xFE;
+					break;
+				case DLIGHT_SPOT:
+					light->type = LIGHT_SPOT;
+					// Copy spot data
+					add_dlight_spot(dlight, light);
+					hash.model = 0xFD;
+					break;
+			}
+
+			light_entity_ids[(*num_lights)] = *(uint32_t*)&hash;
+			(*num_lights)++;
+
+		}
 	}
 }
 
@@ -1860,7 +1877,7 @@ static inline void transform_point(const float* p, const float* matrix, float* r
 	VectorCopy(transformed, result); // vec4 -> vec3
 }
 
-static void instance_model_lights(int num_light_polys, const light_poly_t* light_polys, const float* transform)
+static void instance_model_lights(int num_light_polys, const light_poly_t* light_polys, const float* transform, entity_hash_t hash)
 {
 	for (int nlight = 0; nlight < num_light_polys; nlight++)
 	{
@@ -1890,10 +1907,15 @@ static void instance_model_lights(int num_light_polys, const light_poly_t* light
 		VectorCopy(src_light->color, dst_light->color);
 		dst_light->material = src_light->material;
 		dst_light->style = src_light->style;
+		dst_light->type = LIGHT_POLYGON;
+
+		hash.mesh = nlight; //More a light index than a mesh
+		light_entity_ids[entity_frame_num][num_model_lights] = *(uint32_t*)&hash;
 
 		num_model_lights++;
 	}
 }
+
 static const mat4 g_identity_transform = {
 	{ 1.f, 0.f, 0.f, 0.f },
 	{ 0.f, 1.f, 0.f, 0.f },
@@ -1973,7 +1995,7 @@ static void process_bsp_entity(const entity_t* entity, int* instance_count)
 	mi->render_buffer_idx = VERTEX_BUFFER_WORLD;
 	mi->render_prim_offset = model->geometry.prim_offsets[0];
 
-	instance_model_lights(model->num_light_polys, model->light_polys, transform);
+	instance_model_lights(model->num_light_polys, model->light_polys, transform, hash);
 
 	if (model->geometry.accel)
 	{
@@ -2166,7 +2188,13 @@ static void process_regular_entity(
 		mult_matrix_vector(end, transform, offset2);
 		VectorSet(color, 0.25f, 0.5f, 0.07f);
 
-		vkpt_build_cylinder_light(model_lights, &num_model_lights, MAX_MODEL_LIGHTS, bsp_world_model, begin, end, color, 1.5f);
+		entity_hash_t hash;
+		hash.entity = entity->id;
+		hash.model = entity->model;
+		hash.mesh = 0;
+		hash.bsp = 0;
+
+		vkpt_build_cylinder_light(model_lights, &num_model_lights, MAX_MODEL_LIGHTS, bsp_world_model, begin, end, color, 1.5f, hash, light_entity_ids[entity_frame_num]);
 	}
 
 	*instance_count = current_instance_index;
@@ -2241,7 +2269,13 @@ prepare_entities(EntityUploadInfo* upload_info)
 				else
 					create_entity_matrix(transform, (entity_t*)entity);
 
-				instance_model_lights(model->num_light_polys, model->light_polys, transform);
+				entity_hash_t hash;
+				hash.entity = i + 1;
+				hash.model = ~entity->model;
+				hash.mesh = 0;
+				hash.bsp = 0;
+
+				instance_model_lights(model->num_light_polys, model->light_polys, transform, hash);
 			}
 		}
 	}
@@ -2318,6 +2352,7 @@ prepare_entities(EntityUploadInfo* upload_info)
 
 	memset(instance_buffer->model_current_to_prev, -1, sizeof(instance_buffer->model_current_to_prev));
 	memset(instance_buffer->model_prev_to_current, -1, sizeof(instance_buffer->model_prev_to_current));
+	memset(instance_buffer->mlight_prev_to_current, ~0u, sizeof(instance_buffer->mlight_prev_to_current));
 
 	model_entity_id_count[entity_frame_num] = model_instance_idx;
 	for(int i = 0; i < model_entity_id_count[entity_frame_num]; i++) {
@@ -2937,8 +2972,6 @@ prepare_ubo(refdef_t *fd, mleaf_t* viewleaf, const reference_mode_t* ref_mode, c
 	VectorCopy(sky_matrix[0], ubo->environment_rotation_matrix[0]);
 	VectorCopy(sky_matrix[1], ubo->environment_rotation_matrix[1]);
 	VectorCopy(sky_matrix[2], ubo->environment_rotation_matrix[2]);
-
-	add_dlights(vkpt_refdef.fd->dlights, vkpt_refdef.fd->num_dlights, ubo);
 
 	if (wm->num_cameras > 0)
 	{
@@ -2955,6 +2988,21 @@ prepare_ubo(refdef_t *fd, mleaf_t* viewleaf, const reference_mode_t* ref_mode, c
 	ubo->num_cameras = wm->num_cameras;
 }
 
+static void
+update_mlight_prev_to_current(void)
+{
+	light_entity_id_count[entity_frame_num] = num_model_lights;
+	for(int i = 0; i < light_entity_id_count[entity_frame_num]; i++) {
+		entity_hash_t hash = *(entity_hash_t*)&light_entity_ids[entity_frame_num][i];
+		if(hash.entity == 0u) continue;
+		for(int j = 0; j < light_entity_id_count[!entity_frame_num]; j++) {
+			if(light_entity_ids[entity_frame_num][i] == light_entity_ids[!entity_frame_num][j]) {
+				vkpt_refdef.uniform_instance_buffer.mlight_prev_to_current[j] = i;
+				break;
+			}
+		}
+	}
+}
 
 /* renders the map ingame */
 void
@@ -3043,9 +3091,12 @@ R_RenderFrame_RTX(refdef_t *fd)
 		vkpt_pt_instance_model_blas(&vkpt_refdef.bsp_mesh_world.geom_sky,         g_identity_transform, VERTEX_BUFFER_WORLD, -1, 0);
 		vkpt_pt_instance_model_blas(&vkpt_refdef.bsp_mesh_world.geom_custom_sky,  g_identity_transform, VERTEX_BUFFER_WORLD, -1, 0);
 
-		vkpt_build_beam_lights(model_lights, &num_model_lights, MAX_MODEL_LIGHTS, bsp_world_model, fd->entities, fd->num_entities, prev_adapted_luminance);
+		vkpt_build_beam_lights(model_lights, &num_model_lights, MAX_MODEL_LIGHTS, bsp_world_model, fd->entities, fd->num_entities, prev_adapted_luminance, light_entity_ids[entity_frame_num], &num_model_lights);
+		add_dlights(vkpt_refdef.fd->dlights, vkpt_refdef.fd->num_dlights, model_lights, &num_model_lights, MAX_MODEL_LIGHTS, bsp_world_model, light_entity_ids[entity_frame_num]);
 	}
 
+	update_mlight_prev_to_current();
+
 	vkpt_vertex_buffer_ensure_primbuf_size(upload_info.num_prims);
 
 	QVKUniformBuffer_t *ubo = &vkpt_refdef.uniform_buffer;

src/refresh/vkpt/path_tracer.c

@@ -104,6 +104,7 @@ cvar_t*                      cvar_pt_enable_sprites = NULL;
 
 extern cvar_t *cvar_pt_caustics;
 extern cvar_t *cvar_pt_reflect_refract;
+extern cvar_t *cvar_pt_restir;
 
 
 typedef struct QvkGeometryInstance_s {
@@ -1139,6 +1140,11 @@ vkpt_pt_trace_lighting(VkCommandBuffer cmd_buf, float num_bounce_rays)
 	BARRIER_COMPUTE(cmd_buf, qvk.images[VKPT_IMG_PT_COLOR_HF]);
 	BARRIER_COMPUTE(cmd_buf, qvk.images[VKPT_IMG_PT_COLOR_SPEC]);
 
+	if(cvar_pt_restir->value != 0) {
+		int frame_idx = qvk.frame_counter & 1;
+		BARRIER_COMPUTE(cmd_buf, qvk.images[VKPT_IMG_PT_RESTIR_A + frame_idx]);
+	}
+
 	BUFFER_BARRIER(cmd_buf,
 		.srcAccessMask = VK_ACCESS_SHADER_WRITE_BIT,
 		.dstAccessMask = VK_ACCESS_TRANSFER_READ_BIT,

src/refresh/vkpt/shader/constants.h

@@ -114,6 +114,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #define MAX_TLAS_INSTANCES       (MAX_MODEL_INSTANCES + MAX_RESERVED_INSTANCES)
 #define MAX_LIGHT_SOURCES        32
 #define MAX_LIGHT_STYLES         64
+#define MAX_MODEL_LIGHTS         16384
 
 #define TLAS_INDEX_GEOMETRY      0
 #define TLAS_INDEX_EFFECTS       1
@@ -161,9 +162,10 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #define M_PI 3.1415926535897932384626433832795
 #endif
 
-// Dynamic light types
-#define DYNLIGHT_SPHERE         0
-#define DYNLIGHT_SPOT           1
+// Light types
+#define LIGHT_POLYGON        0
+#define LIGHT_SPHERE         1
+#define LIGHT_SPOT           2
 
 //
 // Spotlight styles (emission profiles)