Geometry Classes

This topic provides an introduction to the TPoint, TSize, TRect and TRegion basic graphics classes.

A TPoint stores and provides the means for manipulating conceptual points and sizes. It consists of a pair of (x,y) co-ordinates.

A TSize is described in terms of a width and height.

A TRect represents a rectangle whose sides are parallel with the axes of the co-ordinate system. It is described by the co-ordinates of its top left and bottom right corners, or by its top left hand corner and its size.

A TRegion consists of one or more TRect s. All Draw() functions draw to a TRect rather than to a TRegion because calculating the dimensions of a TRegion is too complex for the requirements of most applications. TRegion s are principally used when drawing sprites.

The classes: RRegion, RRegionBuf<class S> and TRegionFix<class S> all derive from TRegion.