Added the feature to hide objects behind invisible objects (occlusion).
Thw workflow is:
Call context.setColorMask(false, false, false, false);
Draw the object, that shall hide other objects.
Call context.setColorMask(true, true, true, true);

The OcclusionMaterial is a ColorMaterial, that calls
context.setColorMask(false, false, false, false); in its updateMaterial method
and
context.setColorMask(true, true, true, true); in its cleanMaterial method.

Added cleanMaterial beside updateMaterial in MaterialBase.
clean Material is called in DefaultRenderer.drawRenderables

I'm not sure, whether this fits your engine.
Update:
Only OcclusionMaterial has to be added to the master, since all the magic setColorMask calls are now being done inside this class.

----
Added the feature to hide objects behind invisible objects (occlusion).
Thw workflow is:
Call context.setColorMask(false, false, false, false);
Draw the object, that shall hide other objects.
Call context.setColorMask(true, true, true, true);

The OcclusionMaterial is a ColorMaterial, that calls
context.setColorMask(false, false, false, false); in its updateMaterial method
and
context.setColorMask(true, true, true, true); in its cleanMaterial method.

Added cleanMaterial beside updateMaterial in MaterialBase.
clean Material is called in DefaultRenderer.drawRenderables

I'm not sure, whether this fits your engine. (reverse-merged from commit 69349920c962197bbc57ee535b7f6bfdeb8064ed)
update HoverController. Allow _steps to be 0 so panAngle and tiltAngle can resolve to their targets immediately.
fix unpaired mouse over/mouse out events
fix ObjectContainer3D bounds calculation
added removeChildAt function
OBJParser: do not create zero-length geometries
check for zero-length data in CompactSubGeometry
normalize normals and tangents after transform
optimize RegisterPool creation
Refactoring of ParticleNodeBase

Now users can use ParticleNode.name in most easy way
Now ImageParser can work with BitmapData
Be able to set profile
Some optimizations in lighting
Pass on profile for animation fragment code
Support for single-light setups in normal material framework in constrained mode
Fix depth test in multipass, removed texture and program state setting from proxy
Merge branch 'constrained_mode' into dev
Redo lightpicker assignments
Merge remote-tracking branch 'Alexx999/dev' into dev

Conflicts:
	src/away3d/core/managers/Mouse3DManager.as