Relevant to Blender v2.31
There are several other application for IPOs other than just animating an Object movement.
The IPO Type Menu Buttons in the header (Figure 14.6, “The IPO window.”) allow IPO Block type selection, the active one there is the Object IPO described up to now, but there are Material IPO, World IPO, Vertex Keys IPO, Constraints IPO and Sequence IPO. Not every entry is always present, depending on context. Curve IPO block appears if the selected object is a curve and not a Mesh, the Lamp IPO only appears if the selected object is a lamp.
Material IPO is a way of animating a Material. Just as with objects, IPO Curves can be used to specify 'key positions' for Materials. With the mouse in the ButtonsWindow, the command IKEY calls up a pop-up menu with options for the various Material variables. If you are in a Material, Lamp or World IPO Block then a small Num Button appears next to the IPO type Menu in the IPO Window toolbar. This indicates which texture channel is active. The mapping for all 8 channels can be controlled with IPOCurves!
Strictly speaking, with textures two other animations are possible. Since Objects can give texture coordinates on other objects (Each object in Blender can be used as a source for texture coordinates. To do this, the option "Object" must be selected in the green "Coordinates input" buttons and the name of the object must be filled in. An inverse transformation is now performed on the global render coordinate to obtain the local object coordinate) it is possible to animate the texture simply by animating the location, size, and rotation of the object.
Furthermore, at each frame, Blender can be made to load another (numbered) Image as a texture map instead of having a fixed one. It is also possible to use SGI movie files or AVI files for this.