Translation and Rotation (in 3D!)
“What is the Matrix?”
In this chapter:
– 2D and 3D translation.
– Using P3D and OPENGL.
– Vertex shapes.
– 2D and 3D rotation.
– Saving the transformation state in the stack: pushMatrix() and popMatrix().
14.1 The Z-Axis
As we have seen throughout this book, pixels in a two-dimensional window are described using Cartesian coordinates: an X (horizontal) and a Y (vertical) point. This concept dates all the way back to Chapter 1, when we began thinking of the screen as a digital piece of graph paper.
In three-dimensional space (such as the actual, real-world space where you are reading this book), a third axis (commonly referred to as the Z-axis) refers to the depth of any given point. In a ...