A display apparatus includes means for detecting gaze direction of user; processor configured to process input image based upon gaze direction to generate first and second images; first and second image renderers to render first and second images; optical combiner; first array of micro-prisms to split light emanating from second image renderer into multiple directions to produce multiple projections of second image; optical element to direct said multiple projections towards optical combiner; and optical shutter arranged between optical element and optical combiner, wherein optical shutter allows given portion of said multiple projections to pass, whilst blocking remaining portion of said multiple projections. The optical combiner optically combines projection of first image with given portion of said multiple projections, to produce on image plane output image having spatially-variable angular resolution. The processor controls optical shutter based upon detected gaze direction, whilst first and second images are being rendered.