prep - Control Value Program

The Control Value Program consists of a set of TrueType instructions that will be executed whenever the font or point size or transformation matrix change and before each glyph is interpreted. Any instruction is legal in the CVT Program but since no glyph is associated with it, instructions intended to move points within a particular glyph outline cannot be used in the CVT Program. The name 'prep' is anachronistic.
Type Description
BYTE[ ]Set of instructions executed whenever point size or font or transformation change