up/down arrow: move Forward/Back (inc/dec cameraZ)
left/right arrow: rotate (turn) left/right
mn: move Left/Right (inc/dec cameraX)
comma, period: mvove Up/Down (inc/dec cameraY)
uv: inc/dec phi, to rotate a wall
rt: toggle RotateX, RotateZ variables
x: Flip X coords
yz: Swap X,Y or swap X,Z coords