Fix for scene load fail

Fix scene failing to load for scenes with existing sources (issue #34).

Terrain walls and geometry submodule

Add a shared geometry git submodule.
Clearly differentiate WebGL vs non-WebGL (Polygons) shadows in settings.
Add setting to disable shadows altogether (issue #30).
Handle limited-sight (terrain) walls in both Polygons and WebGL settings (issue #21).
Handle shadows for walls whose bottom elevation is above the canvas (issue #33).
Fix for conflict with Flying Tokens Module (issue #32).
Add an elevation setting for light configuration.

Bug fix re rangeBottom

Potential fix for issue #29 (canvas freeze re "rangeBottom")

Remove 3d visibility testing

Remove 3d visibility code. (Taken over by Alternative Token Visibility. Perfect Vision or Levels will also work for this.)

Remove dependency on Wall Height. (Still highly recommended.)

Levels improvements

Incorporate update from Perfect Vision 4.0.34; no longer need to force PV into debug mode.

Fix issue #27 (Elevation fill not getting saved to scene).

Fix issue #23 (Avoid changing elevations when min or step elevation is changed).

Fix issue #20 (Check for elevated tiles before adjusting token elevation). EV now considers tokens on tiles to be "on the ground" if the token and tile elevation are the same. This should allow creation of "bridges" made of tiles and better functionality with Levels.

Fix issue #26 (Vision broken when using Levels). EV will now set the scene minimum elevation to the minimum tile elevation. In addition, for basements, it is necessary that the terrain elevation around the basement be modified to equal the basement level. (E.g., if the basement is at -10, color all the elevation tiles around the basement to -10.)

EV will now exclude from shadow calculations walls under tiles, or walls under elevation 0 if the vision or light source is above the tile. This avoids rendering shadows in unexpected places, such as in a building set up for Levels where the walls should only appear if the token is at the same level as the walls.

Perfect Vision

Compatibility with Perfect Vision should be much improved (issues #4 and #18). Added an additional non-radius vision shader and simplified the shader geometry calculation. This also addresses issue #15 in a more comprehensive way.

Fix for calculating averageElevationAtGridPoint.

Fix issue #19 (default elevation). Added a method, changePixelElevationValues, that changes every pixel that is currently at a specified elevation to a different elevation. Also added a macro for easy access to this functionality. This allows, for example, the user to change the scene from the default value to some other value.

Sight.range = 0 fix

Fix for issue #15 (no vision when sight.range = 0). To avoid a possible bug in PolygonMesher and because ShadowShader assumes normalized geometry based on radius, set radius to 1 if radius is 0.

Inverted shadows fix

Fix for issue #17 (inverted polygon shadows).
Avoid combining shadows unless required for vision, which provides performance improvement when using the shader for vision shadows.

Levels compatibility and bug fixes

Fix for testing detect range. This should fix functionality for detect tremor. Note that detection is using a 3d range, which affects detection when token or target is elevated. Tremor does not currently consider whether or not a token is "on the ground."

Fix for issue #16 (negative elevation).
Fix for issue #12 (levels compatibility) and #14 (_testRange check).
Possible fix for issue #15.

Elevated Vision now hands off visibility testing to Levels or Perfect Vision if present. If you see a serious discrepancy in tokens being visible/not visible in shadows with or without Levels enabled, please submit a Git issue.

Fix for limited vision

Fix for issue #13 (applying elevation data to limited vision).