Transformation Types

There are many types of transformations.

Translation is a transformation of the xy plane that moves a graphics object toward or away from the origin of the surface in the x- or y-direction. For example, moving an object from point A (x1, y1) to point B (x2, y2) is a translation operation in which an object is being moved (y2 y1) points in the y-direction.

Rotation moves an object around a fixed angle around the center of the plane.

In the reflection transformation, an object moves to a position in the opposite direction from an axis, along a line perpendicular to the axis. The resulting object is the same distance from the axis as the original point, but in the opposite direction.

Simple transformations, including rotation, scaling, and reflection are called linear transformations. A linear transformation followed by translation is called an affine transformation.

The shearing transformation skews objects based on a shear factor. In the sample applications discussed throughout this chapter, will see how to use these transformations in GDI+.

So far we've looked at only simple transformations. Now let's discuss some more complex transformation-related functionality defined in the .NET Framework library.

What Can You Transform?

You have just seen the basics of transforming lines. We can also transform graphics objects such as points, curves, shapes, images, text, colors, and textures, as well as colors and images used in pens and brushes.