CD Metafile Driver (cdmf.h)
This driver allows the generation of a CD Metafile, a very simple format that includes calls to functions of the CD library and provides persistence to its primitives.
Use
The file is created by calling function cdCreateCanvas(CD_METAFILE, Data). The Data parameter is a string that must contain the filename and the canvas dimensions, in the following format:
''filename [widthxheight resolution]'' or in C use "%s %gx%g %g"
Only the parameter filename is required. Width and height are provided in millimeters (note the lowercase "x" between them), and their default value in pixels is INT_MAX for both dimensions. Resolution is the number of pixels per millimeter; its default value is "3.8". Width, height and resolution are real values.
Any amount of such canvases may exist simultaneously. It is important to note that a call to function cdKillCanvas is required to close the file properly.
Images - Be careful when saving images in the file, because it uses a text format to store all numbers and texts of primitives, including images, which significantly increases its size.
Extension - Although this is not required, we recommend the extension used for the file to be ".MF".
Behavior of Functions
Coordinate System and Clipping
- cdGetCanvasSize: returns the size used in the call to function cdCreateCanvas.
- cdUpdateYAxis: does nothing.
Attributes
Colors
- cdGetColorPlanes: always returns 24.
Client Images
- cdGetImageRGB: does nothing.
Server Images
- All functions do nothing.
WC
- Implemented directly in the driver.