Converting between Monochrome and Color Data Bit Maps

It is possible to copy a monochrome bit map to a color bit map or device, and to copy a color bit map to a monochrome bit map or device. PM handles these conversions automatically according to the following rules:

• If you are copying a monochrome bit map to a color bit map or to a color or monochrome device surface, a source setting of 1 adopts the current image-foreground color of the target presentation space, and a source setting of 0 adopts the current image-background color of the target presentation space. For example, if the image foreground color is blue and the image background color is yellow in the target presentation space, a monochrome bit map is converted to a blue foreground on a yellow background.

• If you are copying from a monochrome pattern to a color bit map or device, a source setting of 1 adopts the current area-foreground color of the target device and a source setting of 0 adopts the current area-background color of the target device. Note that if image bundle attributes do not exist for the source bit map, as is the case when using GpiWCBitBlt (which uses a bit map handle as the source), then zero source pixels adopt the image background color and nonzero source pixels adopt the image-foreground color of the presentation space.

• If you are copying a color bit map to a monochrome bit map or device, those pels that have the same color as the current image-background color in the source presentation space adopt the image background color of the target presentation space. For example, if the current image-background color in the source presentation space is blue, all blue pels in the bit map take on the color of the current image background in the target presentation space.

  All other pels in the color bit map adopt the current image foreground color of the target presentation space.