ID2D1RenderTarget::CreateCompatibleRenderTarget(D2D1_SIZE_F,D2D1_SIZE_U,ID2D1BitmapRenderTarget**) method (d2d1.h)

Creates a bitmap render target for use during intermediate offscreen drawing that is compatible with the current render target.

Syntax

HRESULT CreateCompatibleRenderTarget(
  D2D1_SIZE_F             desiredSize,
  D2D1_SIZE_U             desiredPixelSize,
  ID2D1BitmapRenderTarget **bitmapRenderTarget
);

Parameters

desiredSize

Type: [in] D2D1_SIZE_F

The desired size of the new render target (in device-independent pixels), if it should be different from the original render target. For more info, see the Remarks section.

desiredPixelSize

Type: [in] D2D1_SIZE_U

The desired size of the new render target in pixels if it should be different from the original render target. For more information, see the Remarks section.

bitmapRenderTarget

Type: [out] ID2D1BitmapRenderTarget**

When this method returns, contains a pointer to a pointer to a new bitmap render target. This parameter is passed uninitialized.

Return value

Type: HRESULT

If this method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.

Remarks

The pixel size and DPI of the new render target can be altered by specifying values for desiredSize or desiredPixelSize.

• If desiredSize is specified but desiredPixelSize is not, the pixel size is computed from the desired size using the parent target DPI. If the desiredSize maps to a integer-pixel size, the DPI of the compatible render target is the same as the DPI of the parent target. If desiredSize maps to a fractional-pixel size, the pixel size is rounded up to the nearest integer and the DPI for the compatible render target is slightly higher than the DPI of the parent render target. In all cases, the coordinate (desiredSize.width, desiredSize.height) maps to the lower-right corner of the compatible render target.
• If the desiredPixelSize is specified and desiredSize is not, the DPI of the new render target is the same as the original render target.
• If both desiredSize and desiredPixelSize are specified, the DPI of the new render target is computed to account for the difference in scale.
• If neither desiredSize nor desiredPixelSize is specified, the new render target size and DPI match the original render target.

The bitmap render target created by this method is not compatible with GDI.

Requirements

See also

ID2D1RenderTarget