This is now a separate type from spritetype which contains an actor pointer instead so that sprite display can be handled without requiring a static sprite array.
* 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°.
* moving polymost_voxdraw into polymost.cpp.
* consolidated all remaining voxel code in hw_voxels.cpp. All original Build voxel code is completely gone now, except for polymost_voxdraw, so this got moved out of the build/ folder.
* integrate Blood's voxel init code into the main function.
* some further cleanup was allowed as a result of this, so engineInit is gone now because these parts can now be done outside the games' app_init functions.
Since these do not fully get processed sequentially the contents need to be preserved until needed.
This required getting rid of the global tsprite array. Polymost still uses a static vatiable, though, but this is only accessed in polymost-exclusive code.
* 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.
* masked walls were inserted into the sprite render list, causing sorting issues and depth fighting (see Duke's cameras and the 'closed' sign in Route66/Carnival.map)
* vertical and horizontal wall sprites needed their sorting functions swapped.
* plane clipping for wall sprites used bad coordinates.
