Any more news on possible fix for shimmering?

  • Heya guys just to detract from the excitement of the Geoconvert tool, Ate you guys any closer to finding out what causes the bad shimmering of buildings in towns?, more so in the Switzerland area, especially Innsbruck, not having a moan, love the Sim, just wondering that's all😎

  • I think the causes are identified but fixing it is not as easy as one may think. Basically we have to work around the existing limitations of the graphics cards.

    In general there are multiple potential reasons for shimmering

    • z-fighting: at a great distances nearby triangles like the triangles of house roofs and the ground are don't have enough depth spacing and tend to switch places in the depth priority: one frame the house roof is in front, the next the ground is in front.
      A solution for decals is already implemented in the Aerofly, I don't know if houses or city models are also rendered closer by... When a lot of houses are in front of each other at great distance under low visibility angle they also start z-flighting, I don't know if it would be suitable to distort the town model and drag out elements that are far away from the camera to fix this?
    • shadow-flickering: at great distances the shadow resolution is reduced to save processing power of the graphics card. But then one pixel in the shadow map is as large as an entire house thus causing large differences in shadow color each frame
      Maybe a rendering technique relative to the ground can be invented so that the shadow map pixels remain static on the ground?
    • anti-aliasing: sharp edges of brightly illuminated roofs and dark walls hit each other in a very few pixels on the screen. The edges tend to jump by single pixels which can be observed by the human eye. Even better smoothing of the edges would take up more processing power.
      But Anti-Aliasing is turned on, maybe it's not sampled often enough? (8x, 16x?)
    • texture-flickering: under a shallow angle high resolution textures become and create artifacts.
      Mip-mapping is already in use to fight against that.

    So yeah, it's not easy to create a non flickering scene with great resolution at great distances and at the same time have high resolution very close to the camera. The native format of floating point numbers used in graphics card just isn't optimal for this. Double precision graphics card are on it's way but it looks like we might be stuck with these sort of problems for a while. It takes a lot of effort to work around these issues so to answer your question: We're working on it and will probably have to experiment with new techniques to get rid of all of the shimmering.