Due to differences in the rasterization rules for simple primitives (lines,
polygons, etc.) between Java 2D and OpenGL, some work is required to make sure
these primitives render "correctly" using the OpenGL pipeline. Work was
recently completed on the X11 and GDI pipelines to ensure proper rendering
of lines and polygons (see 4771101), so similar techniques should be applied to
the methods in OGLRenderer. The existing regression test:
test/sun/java2d/SunGraphics2D/PolyVertTest.java
does a good job of testing many small and degenerate line/polygon cases, so it
should act as a good measure of success when fixing this bug.

Some OpenGL implementations render lines slightly differently than other
implementations, so care must be taken to keep in line with the OpenGL
specification's rules for line rasterization.