Clipping?
transform-origin: 50px 50px 0; transform: perspective(100px) rotateY(45deg);
= [ 1 0 0 50 0 1 0 50 0 0 1 0 0 0 0 1 ] x [ 1 0 0 0 0 1 0 0 0 0 1 0 0 0 -0.01 1 ] x [ 0.707 0 0.707 0 0 1 0 0 -0.707 0 0.707 0 0 0 0 1 ] x [ 1 0 0 -50 0 1 0 -50 0 0 1 0 0 0 0 1 ] = [ 1.061 0 0.354 -3.03 0.354 1 -0.354 -17.67 -0.707 0 0.707 35.355 0.007 0 -0.007 0.646 ] Compute bottom right point at (100,100) [ 1.061 0 0.354 -3.03 0.354 1 -0.354 -17.67 -0.707 0 0.707 35.35 0.007 0 -0.007 0.646 ] x [ 100 100 0 1 ] = [ 103.037 117.682 -35.35 1.356 ]

x=76.12 y=89.94 z=-26.12

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