A device context (DC) is a GDI structure containing information that governs the display of text and graphics on a particular output device. You use a DC to store, retrieve, and modify the attributes of graphic objects and to specify graphic modes. The graphic objects stored in a DC include a pen for line drawing, a brush for painting and filling, a font for text output, a bitmap for copying or scrolling, a palette for defining the available colors, and a region for clipping.
DCs supported by Windows CE are described in the following table.
| Device context type | Description |
|---|---|
| Display | Supports drawing operations on display devices. |
| Printer | Supports drawing operations on printers. |
| Memory | Supports drawing operations on device-dependent bitmaps or DIB sections. |
The graphics modes control general display characteristics, such as how colors are mixed. Graphics modes supported by Windows CE are described in the following table.
| Graphics mode type | Description |
|---|---|
| Background Mode | Defines how background colors are mixed with window or screen colors for text and bitmap operations. |
| Drawing Mode | Defines how foreground colors are mixed with window or screen colors for pen, brush, bitmap, and text operations. |
Note Windows CE does not support multiple mapping modes. The only mapping mode is MM_TEXT, which maps logical coordinates to the physical coordinates in a 1:1 ratio from left to right and top to bottom.