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Again, I don't quite know if i got the title write. Anywho, a friend of mine started working on a big 3D Model of a city and asked me i can do a small app to view and walk in his city. Made a placeholder and coded it, but I'm facing a small problem. Is there something i can do to stop the camera passing trough walls? And i do not mean, collision because i already have that sorted out! If i am "sliding" near a wall, there are a few chances i will see right trough it! Here's an example:
Walking near the wall

Walking alongside with the wall

I got collision all sorted out by using a cube, and moving it around, positioning the camera at the same place with the cube (*cough* will have some rocket launches attacking the player, collision with him needed*cough), so it's not about collision. Is there something i could do?