OpenXR - Simplify projection matrix creation

Common/VR/VRRenderer.cpp

@@ -312,27 +312,14 @@ bool VR_InitFrame( engine_t* engine ) {
 			float tanAngleDown = tanf(fov.angleDown);
 			float tanAngleUp = tanf(fov.angleUp);
 
-			float M[16];
+			float M[16] = {};
 			M[0] = 2 / (tanAngleRight - tanAngleLeft);
-			M[1] = 0;
 			M[2] = (tanAngleRight + tanAngleLeft) / (tanAngleRight - tanAngleLeft);
-			M[3] = 0;
-
-			M[4] = 0;
 			M[5] = 2 / (tanAngleUp - tanAngleDown);
 			M[6] = (tanAngleUp + tanAngleDown) / (tanAngleUp - tanAngleDown);
-			M[7] = 0;
-
-			// place the far plane at infinity
-			M[8] = 0;
-			M[9] = 0;
 			M[10] = -1;
 			M[11] = -(nearZ + nearZ);
-
-			M[12] = 0;
-			M[13] = 0;
 			M[14] = -1;
-			M[15] = 0;
 
 			memcpy(vrMatrix[matrix], M, sizeof(float) * 16);
 		} else if ((matrix == VR_VIEW_MATRIX_LEFT_EYE) || (matrix == VR_VIEW_MATRIX_RIGHT_EYE)) {