Also updated material densities and added attribute MaxPickDensity to pickaxe, so it's now possible to define a pickaxe that cannot go through granite.
Previously, smooth materials would get extra triangles at the top to create
slopes instead of steps. Now those also appear at the bottom.
Smooth also gets generally smoother at the bottom, while Rough gets rougher
at the top. The new Smoother material is somewhere between Flat and Smooth.
Octagon is like Flat but also gets straight slope triangles.
The idea is that for some materials (e.g. earth chunks) it really
doesn't make sense to not immediately collect them - they would just
collide with something and recreate the material you just dug out.
So instead, this allows materials to specify that they want their
dug out objects to be collected immediately - if not, they simply
don't get created.
Note that this doesn't mean that material is lost, as it will simply
acumulate in the digger's material list instead. We might want to
cap that at some point though.
+ Refactored the ShakeFree, BlastFree, DigFree, DrawQuad etc. functions and
removed unused functions ClearRectDensity, DigFreeMaterial,...
+ Moved the polygon fill algorithm from StdSurface8.cpp to C4Landscape.cpp
+ Clearance functions which used to subtract a circle now subtract something
that looks more like a chunk
+ Pickaxe works with BlastFree now
+ Removed Dig2ObjectRequest
Clonkonaut