One of my teaching samples has died in 1.0.9! (Although the bug may have
crept in earlier)

Moving some geometry below the camera using applyMatrix causes some
multiplication artefacts.

I've simplified to demonstrate the bug below (affects both Mac and PC).

Example:

// try this with PGraphicsOpenGL to see expected outcome
void setup()
{
size(400,400,P3D);
PMatrix3D mat = new PMatrix3D();
mat.translate(width/2,0,height/2);
applyMatrix(mat);
// a box below the camera
translate(0,height,0);
box(width*2,10,height*2);
}

*** This bug has been marked as a duplicate of 1393 ***