Update brute ray shader

Libraries/renderlib/Shaders/src/raytrace_brute.hlsl

@@ -1,4 +1,3 @@
-
 #include "std/rand.hlsl"
 #include "std/attrib.hlsl"
 #include "std/math.hlsl"
@@ -89,6 +88,13 @@ void raygeneration() {
 			TraceRay(scene, RAY_FLAG_FORCE_OPAQUE, ~0, 0, 1, 0, ray, payload);
 			#endif
 
+			#ifdef _EMISSION
+			if (payload.color.a  == -2) {
+				accum += payload.color.rgb;
+				break;
+			}
+			#endif
+
 			// Miss
 			if (payload.color.a < 0) {
 				#ifdef _TRANSPARENCY
@@ -97,7 +103,6 @@ void raygeneration() {
 					transparentHits++;
 					i--;
 				}
-				// else {
 				#endif
 
 				if (i == 0 && constant_buffer.params.x < 0) { // No envmap
@@ -167,7 +172,7 @@ void closesthit(inout RayPayload payload, in BuiltInTriangleIntersectionAttribut
 
 	float4 texpaint1 = mytexture1.Load(uint3(tex_coord * size, 0));
 	float4 texpaint2 = mytexture2.Load(uint3(tex_coord * size, 0));
-	float3 color = payload.color.rgb * pow(texpaint0.rgb, float3(2.2, 2.2, 2.2));
+	float3 texcolor = pow(texpaint0.rgb, float3(2.2, 2.2, 2.2));
 
 	float3 tangent = float3(0, 0, 0);
 	float3 binormal = float3(0, 0, 0);
@@ -177,26 +182,27 @@ void closesthit(inout RayPayload payload, in BuiltInTriangleIntersectionAttribut
 	texpaint1.g = -texpaint1.g;
 	n = mul(texpaint1.rgb, float3x3(tangent, binormal, n));
 
+	float3 diffuseDir = cos_weighted_hemisphere_direction(n, payload.color.a, seed, constant_buffer.eye.w, mytexture_sobol, mytexture_scramble, mytexture_rank);
 	float f = rand(DispatchRaysIndex().x, DispatchRaysIndex().y, payload.color.a, seed, constant_buffer.eye.w, mytexture_sobol, mytexture_scramble, mytexture_rank);
-	if (f > 0.5) {
-		payload.ray_dir = lerp(reflect(WorldRayDirection(), n), cos_weighted_hemisphere_direction(n, payload.color.a, seed, constant_buffer.eye.w, mytexture_sobol, mytexture_scramble, mytexture_rank), pow(texpaint2.g, 1.2));
+	if (f < 0.5) {
+		float3 specularDir = reflect(WorldRayDirection(), n);
+		payload.ray_dir = lerp(specularDir, diffuseDir, texpaint2.g * texpaint2.g);
+		float3 v = normalize(constant_buffer.eye.xyz - hit_world_position());
+		float dotNV = max(dot(n, v), 0.0);
+		float3 specular = surfaceSpecular(texcolor, texpaint2.b);
+		payload.color.xyz *= envBRDFApprox(specular, texpaint2.g, dotNV);
 	}
 	else {
-		payload.ray_dir = cos_weighted_hemisphere_direction(n, payload.color.a, seed, constant_buffer.eye.w, mytexture_sobol, mytexture_scramble, mytexture_rank);
-		color = color * (1.0 - texpaint2.b);
+		payload.ray_dir = diffuseDir;
+		payload.color.xyz *= surfaceAlbedo(texcolor, texpaint2.b);
 	}
 
-	// float dotNL = dot(n, -WorldRayDirection());
-	// float3 wi = payload.ray_dir.x * tangent + payload.ray_dir.y * binormal + payload.ray_dir.z * n;
-	// float dotNV = dot(n, wi);
-
 	payload.ray_origin = hit_world_position() + payload.ray_dir * 0.0001f;
-	payload.color.xyz = color.xyz;
 
 	#ifdef _EMISSION
 	if (texpaint1.a == 1.0) { // matid
 		payload.color.xyz *= 100.0f;
-		payload.color.a = -1.0;
+		payload.color.a = -2.0;
 	}
 	#endif
 
@@ -211,7 +217,7 @@ void closesthit(inout RayPayload payload, in BuiltInTriangleIntersectionAttribut
 void miss(inout RayPayload payload) {
 
 	#ifdef _EMISSION
-	if (payload.color.a == -1.0) {
+	if (payload.color.a == -2.0) {
 		return;
 	}
 	#endif

Libraries/renderlib/Shaders/src/std/math.hlsl

@@ -15,12 +15,6 @@ void create_basis(float3 normal, out float3 tangent, out float3 binormal) {
 	binormal = cross(tangent, normal);
 }
 
-float schlick_weight(float cosTheta) {
-	float m = saturate(1. - cosTheta);
-	float m2 = m * m;
-	return m2 * m2 * m;
-}
-
 void generate_camera_ray(float2 screen_pos, out float3 ray_origin, out float3 ray_dir, float3 eye, float4x4 inv_vp) {
 	screen_pos.y = -screen_pos.y;
 	float4 world = mul(float4(screen_pos, 0, 1), inv_vp);
@@ -38,18 +32,34 @@ float2 equirect(float3 normal, float angle) {
 }
 
 float3 cos_weighted_hemisphere_direction(float3 n, uint sample, uint seed, int frame, Texture2D<float4> sobol, Texture2D<float4> scramble, Texture2D<float4> rank) {
-	float2 r = float2(
-		rand(DispatchRaysIndex().x, DispatchRaysIndex().y, sample, seed, frame, sobol, scramble, rank),
-		rand(DispatchRaysIndex().x, DispatchRaysIndex().y, sample, seed + 1, frame, sobol, scramble, rank)
-	);
-	float3 uu = normalize(cross(n, float3(0.0, 1.0, 1.0)));
-	float3 vv = cross(uu, n);
-	float ra = sqrt(r.y);
-	float rx = ra * cos(6.2831 * r.x);
-	float ry = ra * sin(6.2831 * r.x);
-	float rz = sqrt(1.0 - r.y);
-	float3 rr = float3(rx * uu + ry * vv + rz * n);
-	return normalize(rr);
+	const float PI = 3.1415926535;
+	const float PI2 = PI * 2.0;
+	float f0 = rand(DispatchRaysIndex().x, DispatchRaysIndex().y, sample, seed, frame, sobol, scramble, rank);
+	float f1 = rand(DispatchRaysIndex().x, DispatchRaysIndex().y, sample, seed + 1, frame, sobol, scramble, rank);
+	float z = f0 * 2.0f - 1.0f;
+	float a = f1 * PI2;
+	float r = sqrt(1.0f - z * z);
+	float x = r * cos(a);
+	float y = r * sin(a);
+	return normalize(n + float3(x, y, z));
+}
+
+float3 surfaceAlbedo(const float3 baseColor, const float metalness) {
+	return lerp(baseColor, float3(0.0, 0.0, 0.0), metalness);
+}
+
+float3 surfaceSpecular(const float3 baseColor, const float metalness) {
+	return lerp(float3(0.04, 0.04, 0.04), baseColor, metalness);
+}
+
+// https://www.unrealengine.com/en-US/blog/physically-based-shading-on-mobile
+float3 envBRDFApprox(float3 specular, float roughness, float dotNV) {
+	const float4 c0 = float4(-1, -0.0275, -0.572, 0.022);
+	const float4 c1 = float4(1, 0.0425, 1.04, -0.04);
+	float4 r = roughness * c0 + c1;
+	float a004 = min(r.x * r.x, exp2(-9.28 * dotNV)) * r.x + r.y;
+	float2 ab = float2(-1.04, 1.04) * a004 + r.zw;
+	return specular * ab.x + ab.y;
 }
 
 #endif

Libraries/renderlib/Sources/arm/render/RenderPathRaytrace.hx

@@ -48,8 +48,9 @@ class RenderPathRaytrace {
 			lastLayer = null;
 		}
 
+		if (!Context.envmapLoaded) Context.loadEnvmap();
 		var probe = Scene.active.world.probe;
-		var savedEnvmap = Context.showEnvmapBlur ? probe.radianceMipmaps[0] : probe.radiance;
+		var savedEnvmap = Context.showEnvmapBlur ? probe.radianceMipmaps[0] : Context.savedEnvmap;
 		var isLive = Config.raw.brush_live && RenderPathPaint.liveLayerDrawn > 0;
 		var materialSpace = UIHeader.inst.worktab.position == SpaceMaterial;
 		var layer = (isLive || materialSpace) ? RenderPathPaint.liveLayer : Context.layer;
@@ -166,8 +167,9 @@ class RenderPathRaytrace {
 			return;
 		}
 
+		if (!Context.envmapLoaded) Context.loadEnvmap();
 		var probe = Scene.active.world.probe;
-		var savedEnvmap = Context.showEnvmapBlur ? probe.radianceMipmaps[0] : probe.radiance;
+		var savedEnvmap = Context.showEnvmapBlur ? probe.radianceMipmaps[0] : Context.savedEnvmap;
 		if (lastEnvmap != savedEnvmap || lastLayer != Context.layer.texpaint) {
 			lastEnvmap = savedEnvmap;
 			lastLayer = Context.layer.texpaint;