Render scenes upside-down to framebuffer objects (FBO). The strange thing
about rendering to OpenGL FBO is that it follows the bottom-left triangle
rasterization rule with common PC GPUs. At least Intel and AMD. NVIDIA to
be tested. My raster-rule-test github gist demonstrates this.
This commit flips coordinates in y-direction, which effectively turns the
bottom-left rule into top-left rule needed for Xbox compatibility.
This (together with the previous commit) fixes Midtown Madness 3 Seine
water rectangular seam rendering artifacts (and the remaining seams are
present with Xbox hardware too.) May fix similar artifacts in other games.
ce936bccdd