#86 Implement SSR (HLSL)

Assets/BuiltIn/Shader/SSR/HLSL/LibSSR.hlsl

@@ -0,0 +1,80 @@
+#define LENGTH 20.0
+
+float3 SSR(const float3 position, const float3 reflection, const float roughness)
+{	
+	float4 projectedCoord;
+
+	float3 beginPosition;
+	float3 endPosition;
+
+	float3 rayPosition = position;
+	float4 viewPosition;
+
+	float3 dir = reflection * LENGTH;
+
+	float mipLevel = roughness * 7.0;
+
+	// base color
+	// convert 3d position to 2d texture coord
+	viewPosition = mul(float4(position, 1.0), uView);
+	projectedCoord = mul(float4(viewPosition.xyz, 1.0), uProjection);
+	projectedCoord.xy = projectedCoord.xy / projectedCoord.w;
+	projectedCoord.xy = float2(0.5, -0.5) * projectedCoord.xy + float2(0.5, 0.5);
+
+	// default reflect color is from position
+	float3 baseColor = uTexLastFrame.SampleLevel(uTexLastFrameSampler, projectedCoord.xy, mipLevel).rgb;
+
+	// ray test
+	for (int i = 6; i >= 0; --i)
+	{
+		// begin ray
+		beginPosition = rayPosition;
+
+		// end ray
+		endPosition = rayPosition + dir;
+
+		// mid ray
+		rayPosition += dir * 0.5;
+
+		// convert 3d position to 2d texture coord
+		viewPosition = mul(float4(rayPosition, 1.0), uView);
+		projectedCoord = mul(float4(viewPosition.xyz, 1.0), uProjection);		
+        projectedCoord.xy = projectedCoord.xy / projectedCoord.w;
+	    projectedCoord.xy = float2(0.5, -0.5) * projectedCoord.xy + float2(0.5, 0.5);
+
+		float3 testPosition = uTexPosition.Sample(uTexPositionSampler, projectedCoord.xy).xyz;
+
+		float3 d1 = testPosition - beginPosition;
+		float lengthSQ1 = d1.x*d1.x + d1.y*d1.y + d1.z*d1.z;
+
+		float3 d2 = testPosition - endPosition;
+		float lengthSQ2 = d2.x*d2.x + d2.y*d2.y + d2.z*d2.z;
+
+		// beginPosition is nearer
+		if (lengthSQ1 < lengthSQ2)
+		{
+			rayPosition = beginPosition;
+		}
+
+		// binary search test
+		dir *= 0.5;
+	}
+
+	float z = mul(float4(reflection, 0.0), uView).z;
+	z = clamp(z, 0.0, 1.0);
+
+	// convert 3d position to 2d texture coord
+	viewPosition = mul(float4(rayPosition, 1.0), uView);
+	projectedCoord = mul(float4(viewPosition.xyz, 1.0), uProjection);
+	projectedCoord.xy = projectedCoord.xy / projectedCoord.w;
+	projectedCoord.xy = float2(0.5, -0.5) * projectedCoord.xy + float2(0.5, 0.5);
+
+	// default reflect color is from position
+	float3 color = uTexLastFrame.SampleLevel(uTexLastFrameSampler, projectedCoord.xy, mipLevel).rgb;
+
+	// edge factor
+	float2 dCoords = smoothstep(float2(0.0, 0.0), float2(0.5, 0.5), abs(float2(0.5, 0.5) - projectedCoord.xy));
+	float screenEdgefactor = clamp(1.0 - (dCoords.x + dCoords.y), 0.0, 1.0);
+
+	return lerp(baseColor * 0.7, color, screenEdgefactor * z);
+}

Assets/BuiltIn/Shader/SpecularGlossiness/Lighting/HLSL/LibSG.hlsl

@@ -1,12 +1,16 @@
 static const float PI = 3.1415926;
 
 #include "LibSolverMetallic.hlsl"
+#if defined(ENABLE_SSR)
+#include "../../../SSR/HLSL/LibSSR.hlsl"
+#endif
 #include "../../../PostProcessing/HLSL/LibToneMapping.hlsl"
 
 float3 SG(
 	const float3 baseColor,
 	const float spec,
 	const float gloss,
+	const float3 position,
 	const float3 worldViewDir,
 	const float3 worldLightDir,
 	const float3 worldNormal,
@@ -55,7 +59,10 @@ float3 SG(
 	color += indirectColor * diffuseColor * indirectMultiplier / PI;
 
 	// IBL reflection
-	// ...
+#if defined(ENABLE_SSR)	
+	float3 reflection = -normalize(reflect(worldViewDir, worldNormal));
+	color = color + sRGB(SSR(position, reflection, roughness)) * metallic * specularColor;
+#endif
 
 	return color;
 }

Assets/BuiltIn/Shader/SpecularGlossiness/Lighting/HLSL/SGDirectionalLightBakeFS.d.hlsl

@@ -82,6 +82,7 @@ float4 main(PS_INPUT input) : SV_TARGET
 		albedo,
 		data.r,
 		data.g,
+		position,
 		viewDir,
 		uLightDirection.xyz,
 		normal,

Assets/BuiltIn/Shader/SpecularGlossiness/Lighting/HLSL/SGDirectionalLightBakeFS.hlsl

@@ -92,6 +92,7 @@ float3 SG(
 	const float3 baseColor,
 	const float spec,
 	const float gloss,
+	const float3 position,
 	const float3 worldViewDir,
 	const float3 worldLightDir,
 	const float3 worldNormal,
@@ -160,6 +161,7 @@ float4 main(PS_INPUT input) : SV_TARGET
 		albedo,
 		data.r,
 		data.g,
+		position,
 		viewDir,
 		uLightDirection.xyz,
 		normal,

Assets/BuiltIn/Shader/SpecularGlossiness/Lighting/HLSL/SGDirectionalLightFS.d.hlsl

@@ -36,8 +36,12 @@ cbuffer cbPerFrame
 	float3 uLightMultiplier;
 	float3 uShadowDistance;
 	float4x4 uShadowMatrix[3];
+	float4x4 uProjection;
+	float4x4 uView;
 };
 
+#define ENABLE_SSR
+
 #include "LibShadow.hlsl"
 #include "LibSG.hlsl"
 
@@ -72,6 +76,7 @@ float4 main(PS_INPUT input) : SV_TARGET
 		albedo,
 		data.r,
 		data.g,
+		position,
 		viewDir,
 		uLightDirection.xyz,
 		normal,

Assets/BuiltIn/Shader/SpecularGlossiness/Lighting/HLSL/SGDirectionalLightFS.hlsl

@@ -28,6 +28,8 @@ cbuffer cbPerFrame
 	float3 uLightMultiplier;
 	float3 uShadowDistance;
 	float4x4 uShadowMatrix[3];
+	float4x4 uProjection;
+	float4x4 uView;
 };
 float texture2DCompare(float3 uv, float compare) {
 	float depth = uShadowMap.SampleLevel(uShadowMapSampler, uv, 0).r;
@@ -80,6 +82,51 @@ float solveMetallic(float3 diffuse, float3 specular, float oneMinusSpecularStren
 	float D = b * b - 4.0 * a * c;
 	return clamp((-b + sqrt(D)) / (2.0 * a), 0.0, 1.0);
 }
+float3 SSR(const float3 position, const float3 reflection, const float roughness)
+{
+	float4 projectedCoord;
+	float3 beginPosition;
+	float3 endPosition;
+	float3 rayPosition = position;
+	float4 viewPosition;
+	float3 dir = reflection * 20.0;
+	float mipLevel = roughness * 7.0;
+	viewPosition = mul(float4(position, 1.0), uView);
+	projectedCoord = mul(float4(viewPosition.xyz, 1.0), uProjection);
+	projectedCoord.xy = projectedCoord.xy / projectedCoord.w;
+	projectedCoord.xy = float2(0.5, -0.5) * projectedCoord.xy + float2(0.5, 0.5);
+	float3 baseColor = uTexLastFrame.SampleLevel(uTexLastFrameSampler, projectedCoord.xy, mipLevel).rgb;
+	for (int i = 6; i >= 0; --i)
+	{
+		beginPosition = rayPosition;
+		endPosition = rayPosition + dir;
+		rayPosition += dir * 0.5;
+		viewPosition = mul(float4(rayPosition, 1.0), uView);
+		projectedCoord = mul(float4(viewPosition.xyz, 1.0), uProjection);
+        projectedCoord.xy = projectedCoord.xy / projectedCoord.w;
+	    projectedCoord.xy = float2(0.5, -0.5) * projectedCoord.xy + float2(0.5, 0.5);
+		float3 testPosition = uTexPosition.Sample(uTexPositionSampler, projectedCoord.xy).xyz;
+		float3 d1 = testPosition - beginPosition;
+		float lengthSQ1 = d1.x*d1.x + d1.y*d1.y + d1.z*d1.z;
+		float3 d2 = testPosition - endPosition;
+		float lengthSQ2 = d2.x*d2.x + d2.y*d2.y + d2.z*d2.z;
+		if (lengthSQ1 < lengthSQ2)
+		{
+			rayPosition = beginPosition;
+		}
+		dir *= 0.5;
+	}
+	float z = mul(float4(reflection, 0.0), uView).z;
+	z = clamp(z, 0.0, 1.0);
+	viewPosition = mul(float4(rayPosition, 1.0), uView);
+	projectedCoord = mul(float4(viewPosition.xyz, 1.0), uProjection);
+	projectedCoord.xy = projectedCoord.xy / projectedCoord.w;
+	projectedCoord.xy = float2(0.5, -0.5) * projectedCoord.xy + float2(0.5, 0.5);
+	float3 color = uTexLastFrame.SampleLevel(uTexLastFrameSampler, projectedCoord.xy, mipLevel).rgb;
+	float2 dCoords = smoothstep(float2(0.0, 0.0), float2(0.5, 0.5), abs(float2(0.5, 0.5) - projectedCoord.xy));
+	float screenEdgefactor = clamp(1.0 - (dCoords.x + dCoords.y), 0.0, 1.0);
+	return lerp(baseColor * 0.7, color, screenEdgefactor * z);
+}
 static const float gamma = 2.2;
 static const float invGamma = 1.0 / 2.2;
 float3 sRGB(float3 color)
@@ -94,6 +141,7 @@ float3 SG(
 	const float3 baseColor,
 	const float spec,
 	const float gloss,
+	const float3 position,
 	const float3 worldViewDir,
 	const float3 worldLightDir,
 	const float3 worldNormal,
@@ -126,6 +174,8 @@ float3 SG(
 	float3 directionalLight = NdotL * directionLightColor * visibility;
 	float3 color = (directionalLight * directMultiplier + pointLightColor * lightMultiplier) * diffuseColor + specular * specularColor * visibility + light.a * specularColor;
 	color += indirectColor * diffuseColor * indirectMultiplier / PI;
+	float3 reflection = -normalize(reflect(worldViewDir, worldNormal));
+	color = color + sRGB(SSR(position, reflection, roughness)) * metallic * specularColor;
 	return color;
 }
 float4 main(PS_INPUT input) : SV_TARGET
@@ -152,6 +202,7 @@ float4 main(PS_INPUT input) : SV_TARGET
 		albedo,
 		data.r,
 		data.g,
+		position,
 		viewDir,
 		uLightDirection.xyz,
 		normal,

Assets/BuiltIn/Shader/SpecularGlossiness/Lighting/SGDirectionalLight.xml

@@ -19,6 +19,8 @@
 			<uniform name="uLightMultiplier" type="SHADER_VEC3" value="0.0" float="3"/>
 			<uniform name="uShadowDistance" type="SHADOW_MAP_DISTANCE" value="0" float="3"/>
 			<uniform name="uShadowMatrix" type="SHADOW_MAP_MATRIX" value="0" float="16" array="3" matrix="true"/>
+			<uniform name="uProjection" type="DEFERRED_PROJECTION" value="0" float="16" matrix="true"/>
+			<uniform name="uView" type="DEFERRED_VIEW" value="0" float="16" matrix="true"/>
 		</fs>
 	</uniforms>
 	<resources>

Projects/Skylicht/Engine/Source/Material/Shader/CShader.cpp

@@ -33,6 +33,7 @@ This file is part of the "Skylicht Engine".
 #include "ShaderCallback/CShaderShadow.h"
 #include "ShaderCallback/CShaderSH.h"
 #include "ShaderCallback/CShaderParticle.h"
+#include "ShaderCallback/CShaderDeferred.h"
 
 namespace Skylicht
 {
@@ -50,6 +51,7 @@ namespace Skylicht
 		addCallback<CShaderShadow>();
 		addCallback<CShaderSH>();
 		addCallback<CShaderParticle>();
+		addCallback<CShaderDeferred>();
 	}
 
 	CShader::~CShader()
@@ -1052,21 +1054,13 @@ namespace Skylicht
 		{
 		}
 		break;
-		case DEFERRED_VIEW:
-		{
-		}
-		break;
-		case DEFERRED_PROJECTION:
-		{
-		}
-		break;
+		*/
 		case CUSTOM_VALUE:
 		{
 			// todo
 			// set params in callback
 		}
 		break;
-		*/
 		default:
 			return false;
 		}

Projects/Skylicht/Engine/Source/Material/Shader/ShaderCallback/CShaderDeferred.cpp

@@ -0,0 +1,67 @@
+/*
+!@
+MIT License
+
+Copyright (c) 2020 Skylicht Technology CO., LTD
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files
+(the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify,
+merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+This file is part of the "Skylicht Engine".
+https://github.com/skylicht-lab/skylicht-engine
+!#
+*/
+
+#include "pch.h"
+#include "CShaderDeferred.h"
+
+namespace Skylicht
+{
+	core::matrix4 CShaderDeferred::s_projection;
+	core::matrix4 CShaderDeferred::s_view;
+
+	CShaderDeferred::CShaderDeferred()
+	{
+
+	}
+
+	CShaderDeferred::~CShaderDeferred()
+	{
+
+	}
+
+	void CShaderDeferred::OnSetConstants(CShader *shader, SUniform *uniform, IMaterialRenderer* matRender, bool vertexShader)
+	{
+		switch (uniform->Type)
+		{
+		case DEFERRED_VIEW:
+		{
+			if (vertexShader == true)
+				matRender->setShaderVariable(uniform->UniformShaderID, s_view.pointer(), uniform->SizeOfUniform, video::EST_VERTEX_SHADER);
+			else
+				matRender->setShaderVariable(uniform->UniformShaderID, s_view.pointer(), uniform->SizeOfUniform, video::EST_PIXEL_SHADER);
+		}
+		break;
+		case DEFERRED_PROJECTION:
+		{
+			if (vertexShader == true)
+				matRender->setShaderVariable(uniform->UniformShaderID, s_projection.pointer(), uniform->SizeOfUniform, video::EST_VERTEX_SHADER);
+			else
+				matRender->setShaderVariable(uniform->UniformShaderID, s_projection.pointer(), uniform->SizeOfUniform, video::EST_PIXEL_SHADER);
+		}
+		break;
+		default:
+			break;
+		}
+	}
+}