I have removed the m_pHitObject, m_xray and m_testPropName and replace them by a temporary struct "RayCastData" which contains these datas and a collision mask. Finally i add a collision mask argument in the python function "rayCast" :
```
rayCast(to, from, dist, prop, face, xray, poly, mask)
```
It can be useful to hit only object which are on the right colision layer. for example if you have hitbox for a charater or vehicle you don't want to hit it with raycast.
test file : {F237337}
left mouse click on two planes and see console messages.
Somewhat more elaborate test file by @sybren: {F237779}
Look around and click on the cubes. One cube lamp responds, the other doesn't, based on their collision groups.
Reviewers: moguri, hg1, agoose77, campbellbarton, sybren
Reviewed By: agoose77, campbellbarton, sybren
Subscribers: campbellbarton, sergey, blueprintrandom, sybren
Projects: #game_engine, #game_physics
Differential Revision: https://developer.blender.org/D1239