Vector Image Considerations

Up to this point, we've only been giving examples of how to use ImageMan with raster images. It turns out, though, that using ImageMan with vector images is just as easy as using ImageMan with raster images there's just a few differences.

The first thing to do when you open an image is to call the ImgGetInfo function, then check the returned flags; if the IMG_DISP_VECTOR flag is set, the image will display on-screen using a Windows Metafile (the IMG_PRNT_VECTOR flag indicates that the image will print in a vector format as printing is handled differently from on-screen display, you will not normally need to worry about the state of this flag).

When you've determined that a given image is a vector image, there are a few places where you should have code that differs from the code for raster images. Those are as follows:

• ImgCopy cannot be used on vector images.
• ImgGetDIB , ImgGetDIBPtr , ImgGetDataPtr will not work on vector images
• Vector images cannot be exported using the ImgX functions.
• The image manipulation functions rotation, interpolation, contrasting, gamma, color reduction, etc..., do not work on vector images.

Other than these few limitations, vector images can be handled identically to raster images.

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