Old Thames Water Problem Returned in Acceleration, + Others

[Holger 0]

Hi there,actually, the problem isn't with the mesh file but rather with the water polygons, which have fixed heights. Some of the polygon points have wildly inaccurate elevation values leading to those bumps. In other words, a higher-res mesh file wouldn't make any difference.It's not too difficult making a (sloped) flatten for the Thames in SBuilderX, which would override the default flatten. All one has to do is trace the river while slewing in the sim (while being connected to SBuilderX) and then decide on adequate elevation values for each point (you can even use SBuilder to interpolate intermediate points for those).So why are the default polys so messed up? Because the algorithm ACES used utilized the Shuttle Radar (SRTM) elevation data to compute the polygon point heights. Radar data have the unfortunate issue that they trace the top of all surfaces, including man-made structures, and not the ground. That's why most of the bumps in the Thames are where bridges cross the river and it's also why most SRTM-derived mesh files show inner cities to be much more "bumpy" than they should be.Cheers, Holger