diff --git a/shaders/slang/ssao/blur.slang b/shaders/slang/ssao/blur.slang new file mode 100644 index 00000000..b35d087d --- /dev/null +++ b/shaders/slang/ssao/blur.slang @@ -0,0 +1,30 @@ +/* Copyright (c) 2025, Sascha Willems + * + * SPDX-License-Identifier: MIT + * + */ + +import types; + +Sampler2D samplerSSAO; + +[shader("fragment")] +float4 fragmentMain(VSOutput input) +{ + const int blurRange = 2; + int n = 0; + int2 texDim; + samplerSSAO.GetDimensions(texDim.x, texDim.y); + float2 texelSize = 1.0 / (float2)texDim; + float result = 0.0; + for (int x = -blurRange; x <= blurRange; x++) + { + for (int y = -blurRange; y <= blurRange; y++) + { + float2 offset = float2(float(x), float(y)) * texelSize; + result += samplerSSAO.Sample(input.UV + offset).r; + n++; + } + } + return result / (float(n)); +} \ No newline at end of file diff --git a/shaders/slang/ssao/composition.slang b/shaders/slang/ssao/composition.slang new file mode 100644 index 00000000..04991a03 --- /dev/null +++ b/shaders/slang/ssao/composition.slang @@ -0,0 +1,59 @@ +/* Copyright (c) 2025, Sascha Willems + * + * SPDX-License-Identifier: MIT + * + */ + +import types; + +Sampler2D samplerposition; +Sampler2D samplerNormal; +Sampler2D samplerAlbedo; +Sampler2D samplerSSAO; +Sampler2D samplerSSAOBlur; + +struct UBO +{ + float4x4 _dummy; + int ssao; + int ssaoOnly; + int ssaoBlur; +}; +ConstantBuffer uboParams; + +[shader("fragment")] +float4 fragmentMain(VSOutput input) +{ + float3 fragPos = samplerposition.Sample(input.UV).rgb; + float3 normal = normalize(samplerNormal.Sample(input.UV).rgb * 2.0 - 1.0); + float4 albedo = samplerAlbedo.Sample(input.UV); + + float ssao = (uboParams.ssaoBlur == 1) ? samplerSSAOBlur.Sample(input.UV).r : samplerSSAO.Sample(input.UV).r; + + float3 lightPos = float3(0.0, 0.0, 0.0); + float3 L = normalize(lightPos - fragPos); + float NdotL = max(0.5, dot(normal, L)); + + float4 outFragColor; + if (uboParams.ssaoOnly == 1) + { + outFragColor.rgb = ssao.rrr; + } + else + { + float3 baseColor = albedo.rgb * NdotL; + + if (uboParams.ssao == 1) + { + outFragColor.rgb = ssao.rrr; + + if (uboParams.ssaoOnly != 1) + outFragColor.rgb *= baseColor; + } + else + { + outFragColor.rgb = baseColor; + } + } + return outFragColor; +} \ No newline at end of file diff --git a/shaders/slang/ssao/fullscreen.slang b/shaders/slang/ssao/fullscreen.slang new file mode 100644 index 00000000..d734ebc5 --- /dev/null +++ b/shaders/slang/ssao/fullscreen.slang @@ -0,0 +1,16 @@ +/* Copyright (c) 2025, Sascha Willems + * + * SPDX-License-Identifier: MIT + * + */ + +import types; + +[shader("vertex")] +VSOutput vertexMain(uint VertexIndex : SV_VertexID) +{ + VSOutput output; + output.UV = float2((VertexIndex << 1) & 2, VertexIndex & 2); + output.Pos = float4(output.UV * 2.0f - 1.0f, 0.0f, 1.0f); + return output; +} diff --git a/shaders/slang/ssao/gbuffer.slang b/shaders/slang/ssao/gbuffer.slang new file mode 100644 index 00000000..73e4d9dd --- /dev/null +++ b/shaders/slang/ssao/gbuffer.slang @@ -0,0 +1,73 @@ +/* Copyright (c) 2025, Sascha Willems + * + * SPDX-License-Identifier: MIT + * + */ + +struct VSInput +{ + float4 Pos; + float2 UV; + float3 Color; + float3 Normal; +}; + +struct VSOutput +{ + float4 Pos : SV_POSITION; + float3 Normal; + float2 UV; + float3 Color; + float3 WorldPos; +}; + +struct FSOutput +{ + float4 Position : SV_TARGET0; + float4 Normal : SV_TARGET1; + float4 Albedo : SV_TARGET2; +}; + +struct UBO +{ + float4x4 projection; + float4x4 model; + float4x4 view; + float nearPlane; + float farPlane; +}; +ConstantBuffer ubo; + +[[vk::binding(0, 1)]] Texture2D textureColorMap; +[[vk::binding(0, 1)]] SamplerState samplerColorMap; + +[shader("vertex")] +VSOutput vertexMain(VSInput input) +{ + VSOutput output; + output.Pos = mul(ubo.projection, mul(ubo.view, mul(ubo.model, input.Pos))); + output.UV = input.UV; + // Vertex position in view space + output.WorldPos = mul(ubo.view, mul(ubo.model, input.Pos)).xyz; + // Normal in view space + float3x3 normalMatrix = (float3x3)mul(ubo.view, ubo.model); + output.Normal = mul(normalMatrix, input.Normal); + output.Color = input.Color; + return output; +} + +float linearDepth(float depth) +{ + float z = depth * 2.0f - 1.0f; + return (2.0f * ubo.nearPlane * ubo.farPlane) / (ubo.farPlane + ubo.nearPlane - z * (ubo.farPlane - ubo.nearPlane)); +} + +[shader("fragment")] +FSOutput fragmentMain(VSOutput input) +{ + FSOutput output; + output.Position = float4(input.WorldPos, linearDepth(input.Pos.z)); + output.Normal = float4(normalize(input.Normal) * 0.5 + 0.5, 1.0); + output.Albedo = textureColorMap.Sample(samplerColorMap, input.UV) * float4(input.Color, 1.0); + return output; +} \ No newline at end of file diff --git a/shaders/slang/ssao/ssao.slang b/shaders/slang/ssao/ssao.slang new file mode 100644 index 00000000..624a5f78 --- /dev/null +++ b/shaders/slang/ssao/ssao.slang @@ -0,0 +1,70 @@ +/* Copyright (c) 2025, Sascha Willems + * + * SPDX-License-Identifier: MIT + * + */ + +import types; + +Sampler2D samplerPositionDepth; +Sampler2D samplerNormal; +Sampler2D ssaoNoiseSampler; + +struct UBOSSAOKernel +{ + float4 samples[64]; +}; +ConstantBuffer uboSSAOKernel; + +struct UBO +{ + float4x4 projection; +}; +ConstantBuffer ubo; + +[[SpecializationConstant]] const int SSAO_KERNEL_SIZE = 64; +[[SpecializationConstant]] const float SSAO_RADIUS = 0.5; + +[shader("fragment")] +float fragmentMain(VSOutput input) +{ + // Get G-Buffer values + float3 fragPos = samplerPositionDepth.Sample(input.UV).rgb; + float3 normal = normalize(samplerNormal.Sample(input.UV).rgb * 2.0 - 1.0); + + // Get a random vector using a noise lookup + int2 texDim; + samplerPositionDepth.GetDimensions(texDim.x, texDim.y); + int2 noiseDim; + ssaoNoiseSampler.GetDimensions(noiseDim.x, noiseDim.y); + const float2 noiseUV = float2(float(texDim.x) / float(noiseDim.x), float(texDim.y) / (noiseDim.y)) * input.UV; + float3 randomVec = ssaoNoiseSampler.Sample(noiseUV).xyz * 2.0 - 1.0; + + // Create TBN matrix + float3 tangent = normalize(randomVec - normal * dot(randomVec, normal)); + float3 bitangent = cross(tangent, normal); + float3x3 TBN = transpose(float3x3(tangent, bitangent, normal)); + + // Calculate occlusion value + float occlusion = 0.0f; + for(int i = 0; i < SSAO_KERNEL_SIZE; i++) + { + float3 samplePos = mul(TBN, uboSSAOKernel.samples[i].xyz); + samplePos = fragPos + samplePos * SSAO_RADIUS; + + // project + float4 offset = float4(samplePos, 1.0f); + offset = mul(ubo.projection, offset); + offset.xyz /= offset.w; + offset.xyz = offset.xyz * 0.5f + 0.5f; + + float sampleDepth = -samplerPositionDepth.Sample(offset.xy).w; + + float rangeCheck = smoothstep(0.0f, 1.0f, SSAO_RADIUS / abs(fragPos.z - sampleDepth)); + occlusion += (sampleDepth >= samplePos.z ? 1.0f : 0.0f) * rangeCheck; + } + occlusion = 1.0 - (occlusion / float(SSAO_KERNEL_SIZE)); + + return occlusion; +} + diff --git a/shaders/slang/ssao/types.slang b/shaders/slang/ssao/types.slang new file mode 100644 index 00000000..52f46ab3 --- /dev/null +++ b/shaders/slang/ssao/types.slang @@ -0,0 +1,13 @@ +/* Copyright (c) 2025, Sascha Willems + * + * SPDX-License-Identifier: MIT + * + */ + +module types; + +public struct VSOutput +{ + public float4 Pos : SV_POSITION; + public float2 UV; +};