experimental: add per-slot mapmodel scale factors

4th parameter of the "mapmodel" command is now a scale factor between
0.25 and 4.0. Values outside that range (like the dummy zero from old
map config files) are interpreted as 1.0
Scaling does not affect the clipping, which has to be adjusted manually.

DOCREF mapmodel editmapmodelslot

source/src/entities.cpp

@@ -78,7 +78,7 @@ void rendermapmodels()
         {
             mapmodelinfo &mmi = getmminfo(e.attr2);
             if(!&mmi) continue;
-            rendermodel(mmi.name, ANIM_MAPMODEL|ANIM_LOOP, e.attr4, 0, vec(e.x, e.y, S(e.x, e.y)->floor + mmi.zoff + float(e.attr3) / ENTSCALE5), e.attr6, float(e.attr1) / ENTSCALE10, float(e.attr5) / ENTSCALE10, 10.0f);
+            rendermodel(mmi.name, ANIM_MAPMODEL|ANIM_LOOP, e.attr4, 0, vec(e.x, e.y, S(e.x, e.y)->floor + mmi.zoff + float(e.attr3) / ENTSCALE5), e.attr6, float(e.attr1) / ENTSCALE10, float(e.attr5) / ENTSCALE10, 10.0f, 0, NULL, NULL, mmi.scale);
         }
     }
 }