ID2D1Transform::MapInputRectsToOutputRect method

Performs the inverse mapping to MapOutputRectToInputRects.

Syntax

HRESULT MapInputRectsToOutputRect(
  [in] const D2D1_RECT_L *inputRects,
  [in] const D2D1_RECT_L *inputOpaqueRects,
             UINT32      inputRectCount,
             D2D1_RECT_L *outputRect,
             D2D1_RECT_L *outputOpaqueRect
);

Parameters

inputRects [in]

Type: const D2D1_RECT_L*

An array of input rectangles to be mapped to the output rectangle. The inputRects parameter is always equal to the input bounds.

inputOpaqueRects [in]

Type: const D2D1_RECT_L*

An array of input rectangles to be mapped to the opaque output rectangle.

inputRectCount

Type: UINT32

The number of inputs specified. The implementation guarantees that this is equal to the number of inputs specified on the transform.

outputRect

Type: D2D1_RECT_L*

The output rectangle that maps to the corresponding input rectangle.

outputOpaqueRect

Type: D2D1_RECT_L*

The output rectangle that maps to the corresponding opaque input rectangle.

Return value

Type: HRESULT

If the method succeeds, it returns S_OK. If it fails, it returns an HRESULT error code.

Remarks

The transform implementation must ensure that any pixel shader or software callback implementation it provides honors this calculation.

Unlike the MapOutputRectToInputRects and MapInvalidRect functions, this method is explicitly called by the renderer at a determined place in its rendering algorithm. The transform implementation may change its state based on the input rectangles and use this information to control its rendering information. This method is always called before the MapInvalidRect and MapOutputRectToInputRects methods of the transform.

Requirements

See also

ID2D1Transform

ID2D1EffectImpl