vk: bring back SURF_DRAWSKY geometries

Needed to hide invisible geometry on e.g. c5a1. Breaks de_dust2 roofs
(#474). That will need to be addressed some other way.

Still uses special value for base_color texture to signal SKY SURFACE.
A supposedly better way to do this would be to have them have a special
material.

ref/vk/shaders/bounce.comp

@@ -20,7 +20,6 @@ RAY_LIGHT_DIRECT_INPUTS(X)
 
 layout(set=0, binding=20, rgba16f) uniform writeonly image2D out_indirect_diffuse;
 layout(set=0, binding=21, rgba16f) uniform writeonly image2D out_indirect_specular;
-layout(set=0, binding=27) uniform samplerCube skybox;
 
 #include "ray_primary_common.glsl"
 #include "ray_primary_hit.glsl"
@@ -73,6 +72,7 @@ bool getHit(vec3 origin, vec3 direction, inout RayPayloadPrimary payload) {
 		// 2. Same as the above, but also with a completely independent TLAS. Why: no need to mask-check geometry for opaque-vs-alpha
 		const MiniGeometry geom = readCandidateMiniGeometry(rq);
 		const uint tex_base_color = getKusok(geom.kusok_index).material.tex_base_color;
+		// Should never happen: skybox is opaque if (tex_base_color == TEX_BASE_SKYBOX)
 		const vec4 texture_color = texture(textures[nonuniformEXT(tex_base_color)], geom.uv);
 
 		const float alpha_mask_threshold = .1f;
@@ -149,14 +149,8 @@ void computeBounce(ivec2 pix, vec3 direction, out vec3 diffuse, out vec3 specula
 	payload.base_color_a = vec4(0.);
 	payload.emissive = vec4(0.);
 	const vec3 pos = imageLoad(position_t, pix).xyz + geometry_normal * ray_normal_fudge;
-	if (!getHit(pos, bounce_direction, payload)) {
-		const vec3 skycolor = SRGBtoLINEAR(texture(skybox, bounce_direction).rgb);
-		if (brdf_type == DIFFUSE_TYPE) {
-			diffuse += skycolor;
-		} else
-			specular += skycolor;
+	if (!getHit(pos, bounce_direction, payload))
 		return;
-	}
 
 	throughput *= payload.base_color_a.rgb;
 

ref/vk/shaders/light_common.glsl

@@ -117,7 +117,7 @@ bool shadowedSky(vec3 pos, vec3 dir) {
 		| gl_RayFlagsSkipClosestHitShaderEXT
 		;
 	const uint hit_type = traceShadowRay(pos, dir, dist, flags);
-	return payload_shadow.hit_type != SHADOW_MISS;
+	return payload_shadow.hit_type != SHADOW_SKY;
 #elif defined(RAY_QUERY)
 
 	rayQueryEXT rq;
@@ -125,22 +125,28 @@ bool shadowedSky(vec3 pos, vec3 dir) {
 		// Culling for shadows breaks more things (e.g. de_cbble slightly off the ground boxes) than it probably fixes. Keep it turned off.
 		//| gl_RayFlagsCullFrontFacingTrianglesEXT
 		| gl_RayFlagsOpaqueEXT
-		| gl_RayFlagsTerminateOnFirstHitEXT
+		//| gl_RayFlagsTerminateOnFirstHitEXT
 		//| gl_RayFlagsSkipClosestHitShaderEXT
 		;
 	const float L = 10000.; // TODO Why 10k?
 	rayQueryInitializeEXT(rq, tlas, flags, GEOMETRY_BIT_OPAQUE, pos, 0., dir, L);
 
-	// Any intersection results in a shadow
+	// Find closest intersection, and then check whether that was a skybox
 	while (rayQueryProceedEXT(rq)) {}
 
 	if (rayQueryGetIntersectionTypeEXT(rq, true) == gl_RayQueryCommittedIntersectionTriangleEXT) {
-		return true;
+		const uint instance_kusochki_offset = rayQueryGetIntersectionInstanceCustomIndexEXT(rq, true);
+		const uint geometry_index = rayQueryGetIntersectionGeometryIndexEXT(rq, true);
+		const uint kusok_index = instance_kusochki_offset + geometry_index;
+		const Kusok kusok = getKusok(kusok_index);
+
+		if (kusok.material.tex_base_color != TEX_BASE_SKYBOX)
+			return true;
 	}
 
 	// check for alpha-masked surfaces separately
-	// TODO compare with doing it in the same loop as above
-	return shadowTestAlphaMask(pos, dir, L);
+	const float hit_t = rayQueryGetIntersectionTEXT(rq, true);
+	return shadowTestAlphaMask(pos, dir, hit_t);
 
 #else
 #error RAY_TRACE or RAY_QUERY

ref/vk/shaders/ray_common.glsl

@@ -23,6 +23,7 @@ struct RayPayloadOpaque {
 
 #define SHADOW_MISS 0
 #define SHADOW_HIT 1
+#define SHADOW_SKY 2
 
 struct RayPayloadShadow {
 	uint hit_type;

ref/vk/shaders/ray_interop.h

@@ -71,6 +71,8 @@ LIST_SPECIALIZATION_CONSTANTS(DECLARE_SPECIALIZATION_CONSTANT)
 #define MATERIAL_MODE_BLEND_GLOW 5
 #define MATERIAL_MODE_COUNT 6
 
+#define TEX_BASE_SKYBOX 0xffffffffu
+
 struct Material {
 	uint tex_base_color;
 

ref/vk/shaders/ray_primary.comp

@@ -24,8 +24,6 @@ RAY_PRIMARY_OUTPUTS(X)
 
 layout(set = 0, binding = 1) uniform accelerationStructureEXT tlas;
 
-layout(set = 0, binding = 7) uniform samplerCube skybox;
-
 #include "trace_simple_blending.glsl"
 
 struct Ray {
@@ -78,6 +76,7 @@ void main() {
 		;
 	rayQueryInitializeEXT(rq, tlas, flags, GEOMETRY_BIT_OPAQUE | GEOMETRY_BIT_ALPHA_TEST | GEOMETRY_BIT_REFRACTIVE, ray.origin, 0., ray.direction, ray.dist);
 	while (rayQueryProceedEXT(rq)) {
+		// FIXME this is a no-op. It doesn't do what I though it did. Should check for SBT index for alpha-test material instead.
 		if (0 != (rayQueryGetRayFlagsEXT(rq) & gl_RayFlagsOpaqueEXT))
 			continue;
 
@@ -90,6 +89,7 @@ void main() {
 		// 2. Same as the above, but also with a completely independent TLAS. Why: no need to mask-check geometry for opaque-vs-alpha
 		const MiniGeometry geom = readCandidateMiniGeometry(rq);
 		const uint tex_base_color = getKusok(geom.kusok_index).material.tex_base_color;
+		// Should never happen: skybox is opaque if (tex_base_color == TEX_BASE_SKYBOX)
 		const vec4 texture_color = texture(textures[nonuniformEXT(tex_base_color)], geom.uv);
 
 		const float alpha_mask_threshold = .1f;
@@ -105,9 +105,6 @@ void main() {
 		//debug_geometry_index = rayQueryGetIntersectionPrimitiveIndexEXT(rq, true);
 		primaryRayHit(rq, payload);
 		L = rayQueryGetIntersectionTEXT(rq, true);
-	} else {
-		payload.hit_t = payload.prev_pos_t = vec4(ray.origin + ray.direction * ray.dist, ray.dist);
-		payload.emissive.rgb = SRGBtoLINEAR(texture(skybox, ray.direction).rgb);
 	}
 
 	traceSimpleBlending(ray.origin, ray.direction, L, payload.emissive.rgb, payload.base_color_a.rgb);

ref/vk/shaders/ray_primary.rchit

@@ -29,7 +29,10 @@ void main() {
 
 	const Kusok kusok = getKusok(geom.kusok_index);
 
-	{
+	if (kusok.material.tex_base_color == TEX_BASE_SKYBOX) {
+		payload.emissive.rgb = SRGBtoLINEAR(texture(skybox, gl_WorldRayDirectionEXT).rgb);
+		return;
+	} else {
 		const vec4 color = getModelHeader(gl_InstanceID).color * kusok.material.base_color;
 		payload.base_color_a = sampleTexture(kusok.material.tex_base_color, geom.uv, geom.uv_lods) * color;
 		payload.material_rmxx.r = sampleTexture(kusok.material.tex_roughness, geom.uv, geom.uv_lods).r * kusok.material.roughness;

ref/vk/shaders/ray_primary.rmiss

@@ -1,14 +1,4 @@
 #version 460 core
 #extension GL_EXT_ray_tracing: require
 
-#include "ray_primary_common.glsl"
-#include "color_spaces.glsl"
-
-layout(set = 0, binding = 7) uniform samplerCube skybox;
-
-layout(location = PAYLOAD_LOCATION_PRIMARY) rayPayloadEXT RayPayloadPrimary payload;
-
-void main() {
-	// TODO payload.prev_pos_t = payload.hit_t = vec4(geom.pos, gl_HitTEXT);
-	payload.emissive.rgb = SRGBtoLINEAR(texture(skybox, gl_WorldRayDirectionEXT).rgb);
-}
+void main() {}

ref/vk/shaders/ray_primary_hit.glsl

@@ -10,6 +10,7 @@
 
 layout(set = 0, binding = 6) uniform sampler2D textures[MAX_TEXTURES];
 layout(set = 0, binding = 2) uniform UBO { UniformBuffer ubo; } ubo;
+layout(set = 0, binding = 7) uniform samplerCube skybox;
 
 vec4 sampleTexture(uint tex_index, vec2 uv, vec4 uv_lods) {
 #ifndef RAY_BOUNCE
@@ -29,7 +30,10 @@ void primaryRayHit(rayQueryEXT rq, inout RayPayloadPrimary payload) {
 	const Kusok kusok = getKusok(geom.kusok_index);
 	const Material material = kusok.material;
 
-	{
+	if (kusok.material.tex_base_color == TEX_BASE_SKYBOX) {
+		payload.emissive.rgb = SRGBtoLINEAR(texture(skybox, rayDirection).rgb);
+		return;
+	} else {
 		payload.base_color_a = sampleTexture(material.tex_base_color, geom.uv, geom.uv_lods);
 		payload.material_rmxx.r = sampleTexture(material.tex_roughness, geom.uv, geom.uv_lods).r * material.roughness;
 		payload.material_rmxx.g = sampleTexture(material.tex_metalness, geom.uv, geom.uv_lods).r * material.metalness;

ref/vk/shaders/ray_shadow.rchit

@@ -7,5 +7,10 @@
 layout(location = PAYLOAD_LOCATION_SHADOW) rayPayloadInEXT RayPayloadShadow payload_shadow;
 
 void main() {
-	payload_shadow.hit_type = SHADOW_HIT;
+	const int instance_kusochki_offset = gl_InstanceCustomIndexEXT;
+	const int kusok_index = instance_kusochki_offset + gl_GeometryIndexEXT;
+	const Kusok kusok = getKusok(kusok_index);
+	const uint tex_base_color = kusok.material.tex_base_color;
+
+	payload_shadow.hit_type = (kusok.material.tex_base_color != TEX_BASE_SKYBOX) ? SHADOW_HIT : SHADOW_SKY ;
 }

ref/vk/shaders/ray_shadow_interface.glsl

@@ -3,6 +3,7 @@
 
 #define SHADOW_MISS 0
 #define SHADOW_HIT 1
+#define SHADOW_SKY 2
 
 struct RayPayloadShadow {
 	uint hit_type;

ref/vk/vk_brush.c

@@ -778,13 +778,13 @@ static model_sizes_t computeSizes( const model_t *mod ) {
 		case BrushSurface_Water:
 			sizes.water_surfaces++;
 			addWarpVertIndCounts(surf, &sizes.water_vertices, &sizes.water_indices);
-		case BrushSurface_Sky:
 		case BrushSurface_Hidden:
 			continue;
 
 		case BrushSurface_Animated:
 			sizes.animated_count++;
 		case BrushSurface_Regular:
+		case BrushSurface_Sky:
 			break;
 		}
 
@@ -1058,11 +1058,11 @@ static qboolean fillBrushSurfaces(fill_geometries_args_t args) {
 			switch (type) {
 			case BrushSurface_Water:
 			case BrushSurface_Hidden:
-			case BrushSurface_Sky:
 				continue;
 			case BrushSurface_Animated:
 				args.bmodel->animated_indexes[animated_count++] = num_geometries;
 			case BrushSurface_Regular:
+			case BrushSurface_Sky:
 				break;
 			}
 
@@ -1089,7 +1089,10 @@ static qboolean fillBrushSurfaces(fill_geometries_args_t args) {
 
 			model_geometry->index_offset = index_offset;
 
-			{
+			if ( type == BrushSurface_Sky ) {
+#define TEX_BASE_SKYBOX 0xffffffffu // FIXME ray_interop.h
+				model_geometry->material.tex_base_color = TEX_BASE_SKYBOX;
+			} else {
 				ASSERT(!FBitSet( surf->flags, SURF_DRAWTILED ));
 				VK_CreateSurfaceLightmap( surf, args.mod );
 			}