If I understand you correctly, your kinect is at an angle, and you want to find the angle that makes the kinect 90 degrees to the wall, and then project the depth values to the new angle?

If that's right, I think all you need is some trigonometry, and the floorclip plane to figure out the angle in question, and the depth and height to get the x, y coordinates with Cos/Sine. Then some Matrix math to project the depth to the new perspective
and angles

HTH

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