GpiBitBlt requires an application to use device coordinates for the dimensions of the source and target rectangles. GpiBitBlt allows you to direct bit maps to devices other than the screen. It is independent of the drawing mode, but it operates as if in draw mode.

At its simplest, GpiBitBlt copies a whole bit map, unaltered, from a device or bit map source to a device or bit map target. At its most powerful, GpiBitBlt can take a part of or a whole bit map, and alter both its size and appearance in the process of copying it to another device context. A bit map can be copied:

A memory device context (whether it is the source or the target of the GpiBitBlt operation) must have a bit map selected when GpiBitBlt is called.

GpiBitBlt has a number of input parameters, two of which are the handles of two presentation spaces: the source presentation space and the target presentation space. Both of these presentation spaces must be associated with an appropriate device context. Unless the associated device is a banded printer, a single presentation space can be both source and target. This allows you to copy a bit map within a single PM window, or to update the bit map. The source and target rectangles are specified in device coordinates in GpiBitBlt. GpiBitBlt, consequently, is very device-dependent, and should be avoided when creating data for interchange.


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