-Utilize R_RenderSegRange for rending both solid and masked segs in 4 column horizontal blocks.

git-svn-id: http://odamex.net/svn/root/branches/rend32@3872 b0bcef46-2027-0410-bd56-ab726e9a1d04
-Fix a solid column rendering bug that rendered an extra row for toptextures and bottomtextures.

git-svn-id: http://odamex.net/svn/root/branches/rend32@3873 b0bcef46-2027-0410-bd56-ab726e9a1d04
-Rename R_RenderSegRange to R_RenderColumnRange and use it for rendering the sky columns.
-R_RenderColumnRange now also renders columns directly to the screen buffer (r_columnmethod disabled).
-Clean up sky rendering code and fix a bug with r_drawflat enabled.

git-svn-id: http://odamex.net/svn/root/branches/rend32@3874 b0bcef46-2027-0410-bd56-ab726e9a1d04
-Unroll the blitting loop in R_DrawColumnGeneric.
-Use R_FillColumnGeneric and R_DrawColumnGeneric templates for the horizontal interleaving column drawers R_FillColumnHorizP and R_DrawColumnHorizP.
-Add comments indicating the purpose of each of the palettized and direct drawing functions.

git-svn-id: http://odamex.net/svn/root/branches/rend32@3875 b0bcef46-2027-0410-bd56-ab726e9a1d04
-Remove rw_x and rw_stop globals.
-Rename R_RenderSegLoop to R_RenderSegRange with the first and last column numbers as parameters.

git-svn-id: http://odamex.net/svn/root/branches/rend32@3876 b0bcef46-2027-0410-bd56-ab726e9a1d04
-Small fix to r3873 to ensure column drawers render the bottom row of the screen.

git-svn-id: http://odamex.net/svn/root/branches/rend32@3877 b0bcef46-2027-0410-bd56-ab726e9a1d04