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The two checkboxes named “Ignore wall/floor rotation TP” refers to how layers that use the True perspective (TP) effect will behave in regard to the rotation. Rotating the canvas output of a true perspective layer can break the effect of true perspective, for example, true perspective expects the corners of the room to be in one spot, but by changing the output the corners calculated by the true perspective shader will not be in line with the physical corners of the room. If “Ignore wall/floor rotation TP” is enabled all layers with True perspective will compensate its output so that it’s not affected by the canvas rotation. This means that even though all other UI elements and non-TP layers will be rotated, the image of a TP layer will appear to stay in the same place. To change the image of a TP layer, the user should change the “Heading” variable in the TP menu. When this is enabled, the TP layer seems to not be moving in the output, but in the console Canvas tab, the layer texture is rotated, what you see is the compensation for the rotation being applied on output.
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