A bitmap is a matrix of memory bits that, when copied to a device, defines the color and pattern of a corresponding matrix of pixels on the display surface of the device. Bitmaps are useful in drawing, charting, and word-processing applications because they prepare images in memory and then quickly copy them to the display.
The relationship between bitmap bits in memory and pixels on a device is device-dependent. On a monochrome device, the correspondence is usually one-to-one, where one bit in memory corresponds to one pixel on the device.
Bitmap functions display bitmaps. Following are the bitmap functions:
| Function | Description |
| BitBlt | Copies a bitmap from a source to a destination device. |
| CreateBitmap | Creates a bitmap. |
| CreateBitmapIndirect | Creates a bitmap described in a structure. |
| CreateCompatibleBitmap | Creates a bitmap that is compatible with a specified device. |
| CreateDiscardableBitmap | Creates a discardable bitmap that is compatible with a specified device. |
| ExtFloodFill | Fills the display surface within a border or over an area of a given color. |
| FloodFill | Fills the display surface within a border. |
| GetBitmapBits | Retrieves the bits in memory for a specific bitmap. |
| GetBitmapDimension | Retrieves the height and width of a bitmap. |
| GetBitmapDimensionEx | Retrieves the height and width of a bitmap. |
| GetPixel | Retrieves the RGB value for a pixel. |
| LoadBitmap | Loads a bitmap from a resource file. |
| PatBlt | Creates a bit pattern. |
| SetBitmapBits | Sets the bits of a bitmap. |
| SetBitmapDimension | Sets the height and width of a bitmap. |
| SetBitmapDimensionEx | Sets the height and width of a bitmap. |
| SetPixel | Sets the RGB value for a pixel. |
| StretchBlt | Copies a bitmap from a source to a destination device (compressing or stretching the bitmap, if necessary). |
In addition, applications can use the LoadBitmap function from the USER API to load a bitmap from a resource file. For more information about this USER function, see Chapter 1, “Window Management.”