markus_GE, on 22 September 2013 - 02:19 AM, said:
So is OR (except for the new exclusion area) already (partially) not drawing the DM Terrain where it´s overlaid by the normal one?
No, OR is drawing all the low-resolution terrain in the viewing distance (default of 40km) except a 500m exclusion zone. It is then drawing all the high-resolution terrain in that viewing distance (default of 2km) on top of it. I would have liked to use the GPU to help here with its depth buffer, but low-resolution terrain isn't
always lower than high-resolution terrain, alas (mostly it is something like 10m down).
markus_GE, on 22 September 2013 - 02:19 AM, said:
Rewritten for OpR, this means: DM are lowered anyway, so from the cab or any other camera angle Close to the ground, there already is no Chance that the line between DM and normal Terrain can be seen as a gap, if DMs only start where our "plate" (normal Terrain) leaves off (it´ll be noticeable just as a cut in texturing, like we already know it). Now let them start let´s say 50 metres before the "plate" leaves off, and there is no Chance to see a gap any way.
While this is a nice idea, and a good diagram to explain it, you do actually get gaps.
Bug 1213712 has
an examples of such gaps. While we can probably improve that specific case (I don't think we were drawing all the high-resolution terrain we should have been there), there are cases we can't fix so easily.
Firstly, as noted, low-resolution terrain isn't always below high-resolution terrain so if you are switching over (at 2km) and the low-resolution terrain isn't lower, you get a visible gap.
Secondly, and more importantly to me, is the problem of running out of high-resolution terrain before the viewing distance is reached. This happens on various routes with the default 2km viewing distance, but is much worse if people crank that setting up - as people do. For example, what do you think happens if you are on a low-detail route and set it to 10km, and look out to the left of the cab? You see - if you're lucky - 2-3km of high-resolution terrain, then a 7km gap to the low-resolution terrain. Not good.