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ID3D10Device::OMSetBlendState method (d3d10.h)

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Set the blend state of the output-merger stage.

Syntax

void OMSetBlendState(
  [in] ID3D10BlendState *pBlendState,
  [in] const FLOAT [4]  BlendFactor,
  [in] UINT             SampleMask
);

Parameters

[in] pBlendState

Type: ID3D10BlendState*

Pointer to a blend-state interface (see ID3D10BlendState). Passing in NULL implies a default blend state. See remarks for further details.

[in] BlendFactor

Type: const FLOAT

Array of blend factors, one for each RGBA component. The blend factors modulate values for the pixel shader, render target, or both. If you created the blend-state object with D3D10_BLEND_BLEND_FACTOR or D3D10_BLEND_INV_BLEND_FACTOR, the blending stage uses the non-NULL array of blend factors. If you didn't create the blend-state object with D3D10_BLEND_BLEND_FACTOR or D3D10_BLEND_INV_BLEND_FACTOR, the blending stage does not use the non-NULL array of blend factors; the runtime stores the blend factors, and you can later call ID3D11DeviceContext::OMGetBlendState to retrieve the blend factors. If you pass NULL, the runtime uses or stores a blend factor equal to { 1, 1, 1, 1 }.

[in] SampleMask

Type: UINT

32-bit sample coverage. The default value is 0xffffffff. See remarks.

Return value

None

Remarks

Blend state is used by the output-merger stage to determine how to blend together two RGB pixel values and two alpha values. The two RGB pixel values and two alpha values are the RGB pixel value and alpha value that the pixel shader outputs and the RGB pixel value and alpha value already in the output render target. The blend option controls the data source that the blending stage uses to modulate values for the pixel shader, render target, or both. The blend operation controls how the blending stage mathematically combines these modulated values.

To create a blend-state interface, call ID3D10Device::CreateBlendState.

Passing in NULL for the blend-state interface indicates to the runtime to set a default blending state. The following table indicates the default blending parameters.

State Default Value
AlphaToCoverageEnable FALSE
BlendEnable FALSE[8]
SrcBlend D3D10_BLEND_ONE
DstBlend D3D10_BLEND_ZERO
BlendOp D3D10_BLEND_OP_ADD
SrcBlendAlpha D3D10_BLEND_ONE
DstBlendAlpha D3D10_BLEND_ZERO
BlendOpAlpha D3D10_BLEND_OP_ADD
RenderTargetWriteMask[8] D3D10_COLOR_WRITE_ENABLE_ALL[8]
 

A sample mask determines which samples get updated in all the active render targets. The mapping of bits in a sample mask to samples in a multisample render target is the responsibility of an individual application. A sample mask is always applied; it is independent of whether multisampling is enabled, and does not depend on whether an application uses multisample render targets.

The method will not hold a reference to the interfaces passed in. For that reason, applications should be careful not to release an interface currently in use by the device.

Requirements

Requirement Value
Target Platform Windows
Header d3d10.h
Library D3D10.lib

See also

ID3D10Device Interface