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L_DoubleBufferBegin

#include "l_bitmap.h"

L_LTDIS_API L_HDC L_DoubleBufferBegin(hDoubleBufferHandle, hDC, cx, cy)

Returns a memory hDC that is used in the double buffering process.

Parameters

L_HANDLE hDoubleBufferHandle

Handle that identifies the double buffering process.

L_INT cx

Width in pixels, of the target device context.

L_INT cy

Height, in pixels, of the target device context.

Returns

Value	Meaning
<> 0	Memory `hDC` to use for double buffered paints.
0	The function failed.

Comments

Use L_DoubleBufferBegin to begin a double buffering process. All double buffered paint operations should be wrapped in L_DoubleBufferBegin and L_DoubleBufferEnd calls.

The hDC argument is the device context that you want to double buffer. The arguments cx and cy specify the pixel dimensions of the hDC. If the call to L_DoubleBufferBegin is successful, a memory hDC is returned. Use this memory hDC for all subsequent paint operations. When you want the result of the memory hDC to appear on the target hDC, call L_DoubleBufferEnd.

Note that you must create a double buffer handle with L_DoubleBufferCreateHandle before calling this function.

For more information, see the topic Minimizing Flicker With Double Buffering.

Required DLLs and Libraries