Some other software fixes/changes

Some other software fixes/changes I've made

• Change 1: single-sided linedef midtextures (read: not double-sided linedefs, but single-sided) now don't skew if Effect 2 is checked. Before, there wasn't any ability for software to disable skewing for them. =V
• Change 2: PolyObject back side midtextures now return to being where they should be. Had to make a hack to fix this though.

src/r_segs.c

@@ -1883,12 +1883,13 @@ void R_StoreWallRange(INT32 start, INT32 stop)
// a single sided line is terminal, so it must mark ends
markfloor = markceiling = true;
#ifdef ESLOPE
-		if (!(linedef->flags & ML_EFFECT1)) {
+		if (linedef->flags & ML_EFFECT2) {
if (linedef->flags & ML_DONTPEGBOTTOM)
rw_midtexturemid = frontsector->floorheight + textureheight[sidedef->midtexture] - viewz;
else
-				rw_midtexturemid = frontsector->ceilingheight;
+				rw_midtexturemid = frontsector->ceilingheight - viewz;
}
+		else
#endif
if (linedef->flags & ML_DONTPEGBOTTOM)
{
@@ -2507,6 +2508,15 @@ void R_StoreWallRange(INT32 start, INT32 stop)
#ifdef ESLOPE
maskedtextureheight = ds_p->maskedtextureheight; // note to red, this == &(ds_p->maskedtextureheight[0])
+#ifdef POLYOBJECTS
+			if (curline->polyseg) { // use REAL front and back floors please, so midtexture rendering isn't mucked up
+				rw_midtextureslide = rw_midtexturebackslide = 0;
+				if (!!(linedef->flags & ML_DONTPEGBOTTOM) ^ !!(linedef->flags & ML_EFFECT3))
+					rw_midtexturemid = rw_midtextureback = max(curline->frontsector->floorheight, curline->backsector->floorheight) - viewz;
+				else
+					rw_midtexturemid = rw_midtextureback = min(curline->frontsector->ceilingheight, curline->backsector->ceilingheight) - viewz;
+			} else
+#endif
// Set midtexture starting height
if (linedef->flags & ML_EFFECT2) { // Ignore slopes when texturing
rw_midtextureslide = rw_midtexturebackslide = 0;