<cat>Material.ShaderBasic</cat> <title>Constant Buffers</title> # What are constant buffers Constant buffer or "cbuffers" as known by HLSL is a buffer/struct which is stored in GPU memory and can be accessed within your shader. Once the file is included you should be able to access the cbuffer like a regular variable within your shader. An example of its usage can be seen below: ``` COMMON { #include "common/shared.hlsl" // Contains PerViewConstantBuffer_t } VS { #include "common/vertex.hlsl" // // Main // PixelInput MainVs( INSTANCED_SHADER_PARAMS( VS_INPUT i ) ) { PixelInput o = ProcessVertex( i ); o.vPositionWs.z += sin(g_flTime) * 5.0f; // wiggle return FinalizeVertex( o ); } } ``` # Settings constant buffers in code Constant buffers are set using the `RenderAttributes.SetData` function. Much like the other attributes you only need to pass the data itself to the attribute. ```cs struct MyData { public float SomeFloat; public Vector3 SomeVector; } // ... { MyData myStuff = new(); myStuff.SomeFloat = 10.0f; myStuff.SomeVector = Vector3.One; Attributes.SetData( "MyConstBuffer_t", myStuff ); } ``` And accessing it within shaders is as simple as: ```h VS { #include "common/vertex.hlsl" struct MyConstBuffer_t cbuffer MyConstBuffer_t { float SomeFloat; float3 SomeVector; }; // // Main // PixelInput MainVs( INSTANCED_SHADER_PARAMS( VS_INPUT i ) ) { PixelInput o = ProcessVertex( i ); o.vPositionWs += SomeVector * SomeFloat; // Use our constbuffer values! return FinalizeVertex( o ); } } ``` # Built-in constant buffer ## PerViewConstantBuffer_t Usage: `#include "common/shared.hlsl"` | Type | Field | Note | |------|-------|------| | float4x4 | g_matWorldToProjection | | | float4x4 | g_matProjectionToWorld | | | float4x4 | g_matWorldToView | | | float4x4 | g_matViewToProjection | | | float4 | g_vInvProjRow3 | | | float4 | g_vClipPlane0 | | | float | g_flToneMapScalarLinear | | | float | g_flLightMapScalar | | | float | g_flEnvMapScalar | | | float | g_flToneMapScalarGamma | | | float3 | g_vCameraPositionWs | The world position of the camera | | float | g_flViewportMinZ | | | float3 | g_vCameraDirWs | The current camera direction | | float | g_flViewportMaxZ | | | float3 | g_vCameraUpDirWs | | | float | g_flTime | The time since the client has connected | | float3 | g_vDepthPsToVsConversion | | | float | g_flNearPlane | NearZ | | float | g_flFarPlane | FarZ | | float | g_flLightBinnerFarPlane | | | float2 | g_vInvViewportSize | | | float2 | g_vViewportToGBufferRatio | | | float2 | g_vMorphTextureAtlasSize | | | float4 | g_vInvGBufferSize | | | float | g_flOOTransformTextureWidth | | | float | g_flOOTransformTextureHeight | | | float2 | g_vViewportOffset | | | float2 | g_vViewportSize | | | float2 | g_vRenderTargetSize | | | float | g_flFogBlendToBackground | | | float | g_flHenyeyGreensteinCoeff | | | float3 | g_vFogColor | | | float | g_flNegFogStartOverFogRange | | | float | g_flInvFogRange | | | float | g_flFogMaxDensity | | | float | g_flFogExponent | | | float | g_flMod2xIdentity | | | float2 | g_bRoughnessParams | | | bool | g_bUseRoughnessCone | | | bool | g_bUseRoughnessEllipse | | | float | g_bStereoEnabled | | | float | g_flStereoCameraIndex | | | float3 | g_vMiddleEyePositionWs | | | float | g_flPad2 | Padding for alignment, unused | | float4x4 | g_matWorldToProjectionMultiview[ 2 ] | | | float4 | g_vCameraPositionWsMultiview[ 2 ] | | | float4 | g_vFrameBufferCopyInvSizeAndUvScale | | | float4 | g_vCameraAngles | | | float4 | g_vWorldToCameraOffset | | | float4 | g_vWorldToCameraOffsetMultiview[ 2 ] | | | float4 | g_vPerViewConstantExtraData0 | | | float4 | g_vPerViewConstantExtraData1 | | | float4 | g_vPerViewConstantExtraData2 | | | float4 | g_vPerViewConstantExtraData3 | | | float4x4 | m_matPrevProjectionToWorld | | ## PerViewConstantBufferVR_t Usage: `#include "common/shared.hlsl"` | Type | Field | Note | |------|-------|------| | bool | g_bVolumetricFogEnabled | | | bool | g_bGradientFogEnabled | | | bool | g_bCubemapFogEnabled | | | bool | g_bSphericalVignetteEnabled | | | bool | g_bAmbientOcclusionProxiesEnabled | | | float4 | g_vAoProxyDownres | | | float | g_flExcitationAmount | Xen animations | | float | g_flDepressionAmount | Xen animations | | float4 | g_vWindDirection | Current wind direction | | float | g_flWindSpeed | Current wind speed | | float4 | g_vInteractionProjectionOrigin | | | float4 | g_vInteractionVolumeInvExtents | | | float4 | g_vInteractionTriggerVolumeInvMins | | | float4 | g_vInteractionTriggerVolumeWorldToVolumeScale | | | float4 | g_vGradientFogBiasAndScale | | | float4 | m_vGradientFogExponents | | | float4 | g_vGradientFogColor_Opacity | | | float4 | g_vGradientFogCullingParams | | | float | g_flCubeFogOffset | | | float | g_flCubeFogScale | | | float | g_flCubeFogBias | | | float | g_flCubeFogExponent | | | float | g_flCubeFogHeightOffset | | | float | g_flCubeFogHeightScale | | | float | g_flCubeFogHeightExponent | | | float | g_flCubeMapSizeLog2 | | | float4x4 | g_matvCubeFogSkyWsToOs | | | float4 | g_vCubeFogCullingParams | | | float4 | g_vSphericalVignetteBiasAndScale | | | float4 | g_vSphericalVignetteOrigin_Exponent | | | float4 | g_vSphericalVignetteColor_Opacity | | | float | g_flVolFogNearClipPlane | | | float | g_flVolFogClipPlaneRange | | | float4 | g_vVolFogDitherScaleBias | | | float4 | g_vVolFogPostWorldToFrustumScale | | | float4 | g_vVolFogPostWorldToFrustumBias | | | float4x4 | g_mVolFogFromWorld[ 2 ] | | | float4 | g_vHighPrecisionLightingOffsetWs | |