The next important aspect of the painter is its coordinate system. The painter in fact has two coordinate systems. One is its own logical coordinate system that operates on real numbers, and the other is the physical coordinate system of the device the painter operates on. Each operation on the logical coordinate system is mapped to physical coordinates in the device and applied there. Let's start with explaining the logical coordinate system first, and then we'll see how this relates to physical coordinates.
The painter represents an infinite cartesian canvas, with the horizontal axis pointing right and the vertical axis pointing down by default. The system can be modified by applying affine transformations to it—translating, ...
