PBREffect

This effect implements a Disney-style (Roughness/Metalness workflow) Physically-Based Renderer (PBR) effect using Image-Based Lighting (IBL) in combination with up to three directional lights. This effect also supports GPU instancing.

Header

#include <Effects.h>

Initialization

Construction requires a Direct3D 11 device.

std::unique_ptr<PBREffect> effect;
effect = std::make_unique<PBREffect>(device);

For exception safety, it is recommended you make use of the C++ RAII pattern and use a std::unique_ptr or std::shared_ptr

Interfaces

PBREffect supports IEffect, IEffectMatrices, and IEffectLights.

Fog settings are not supported by this effect.

Input layout

This effect requires SV_Position, NORMAL, and TEXCOORD0. It does not support per-vertex color.

If instancing is enabled, this effect also requires these vertex elements:

"InstMatrix",  0, DXGI_FORMAT_R32G32B32A32_FLOAT
"InstMatrix",  1, DXGI_FORMAT_R32G32B32A32_FLOAT
"InstMatrix",  2, DXGI_FORMAT_R32G32B32A32_FLOAT

Properties

SetAlpha: Sets the alpha (transparency) of the effect. Defaults to 1 (fully opaque). This value is also used for binning opaque vs. transparent geometry.
SetConstantAlbedo, SetConstantMetallic, and SetConstantRoughness: Used to set the constant value when not using texturing for the albedo, roughness, and metalness information.
SetAlbedoTexture: Sets the albedo texture. This uses the sampler in slot 0. Can be set to nullptr to remove a reference. Can optionally include an alpha channel as well.
SetNormalTexture: Sets the normal texture. This uses the sampler in slot 0. Can be set to nullptr to remove a reference.

See NormalMapEffect for more details about the normal map texture.

SetRMATexture: Sets the roughness/metalness/ambient-occlusion (RMA) texture. This uses the sampler in slot 0. Can be set to nullptr to remove a reference.

The RMA texture uses the glTF2 standard order: The metalness is in the B channel, roughness in the G channel, and ambient occlusion in the R channel. If there's no ambient occlusion, then the R channel should be set to all 1.

SetEmissiveTexture: Associates an emissive texture with the effect. This uses the sampler in slot 0. Can be set to nullptr to remove a reference.
SetSurfaceTextures: Associates a albedo texture, normal texture, and roughness/metalness/ambient-occlusion (RMA) texture with the effect in one method. This uses the sampler in slot 0. Can be set to nullptr to remove a reference.
SetIBLTextures: Associates a radiance and irradiance texture with the effect. The number of miplevels in the radiance texture is also required as this is used to compute roughness. This uses the sampler in slot 1. Can be set to nullptr to remove a reference.

The radiance and irradiance map are special cubemaps. They are generated by tools like AMD Cubemapgen, cmft/cmftStudio, IBLBaker, and Lys.

SetBiasedVertexNormals: Enables support for compressed vertex normals which require *2 - 1 biasing at runtime such as DXGI_FORMAT_R10G10B10A2_UNORM.
SetInstancingEnabled: Enables support for per-vertex instancing by adding a per-vertex XMFLOAT3X4 transform matrix.
SetVelocityGeneration: Enables the generation of a velocity buffer. If set to true, then both a Render Target 0 and Render Target 1 must be bound for rendering.

This effect does not support both instancing and velocity generation at the same time.

SetRenderTargetSizeInPixels: Used to set the pixel size of the render target when generating velocity buffers.

Remarks

This effect always performs per-pixel lighting. Calls to SetLightingEnabled(false); will generate a C++ exception, and calls to SetPerPixelLighting are ignored.

The lighting modeling for PBR does not make use of an ambient or specular term as these are more directly modeled by the image-based lighting model. Calls to SetAmbientLightColor and SetLightSpecularColor are ignored.

This effect requires a texture sampler in both slots 0 and 1. GeometricPrimitive and SpriteBatch only set a texture sampler in slot 0 by default, Model sets a sampler in slots 0 and 1.