* let the clipper work on relative angles to simplify the math.
* properly initialize the initial visible range and preserve it for multiple invocations.
* track the maximum visible angular range per sector. While possibly not sufficient to handle every edge case imaginable it has low overhead and is still useful to eliminate obvious cases that do not need more complex checks. It is enough to fix the blue door in Duke E3L4.
* removed unused elements of the clipper.
* the bunch drawer can at most process an angular range of 180°. If this gets exceeded it can run into wraparound issues that may cause holes in the geometry.
* there was no clipping to the current field of view so it always checked the full 360°.
* Blood's automap was not drawn at all.
* SW's automap always showed all sectors
* SW's player sprite was not rendered.
* Non-automap: Forward gotsector to the game code because there's still a few places in Blood that need it.
