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Terrain Brush Max size limited to 0.94 max terrain size?

Discussion in 'World Building' started by Jesus, Feb 6, 2019.

  1. Jesus

    Jesus

    Joined:
    Jul 12, 2010
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    483
    Trying out the new terrain system, and I came across a strange limitation.

    If i have the terrain size as 200mx200m, the largest stamp size I can slide to or even enter, is 188m. So if I want a stamp to be corretly aligned at 200x200m, I have to use a terrain of size 212x212m.

    So the stamp max size = terrain size x 0.94.

    Why?


    Is this a hard limitation, or is there some design/development reason the stamp size isn't the same as the max size of the terrain?
     
  2. wyatttt

    wyatttt

    Unity Technologies

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    May 9, 2018
    Posts:
    250
    I'm assuming we limit it because you can only ever paint on at most 4 neighboring Terrain tiles. Increasing the brush size beyond that would mean that any tile that is above the 4 won't be affected by the paint operation. I'll admit, not the best workflow especially if you have small terrain tiles.
     
  3. Jesus

    Jesus

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    Jul 12, 2010
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    Ah right, but in theory that would limit the maximum stamp size to the same size as the terrain though?

    Unless that's a limit based on some sort of lower mip / smoothing algorithm for compatibility between terrains, but I can't figure out what math lead to that. By that reasoning, it would be 1 - (1/512) or 1 - (1/256) or something.

    EDIT:

    0.94 ~= 1 - (1/16) but 16x16 resolution for height or basemap or normal map, maybe the lowest LOD stage for the terrain (does it go as low as 16x16 quads?).
     
  4. wyatttt

    wyatttt

    Unity Technologies

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    That is correct. It'll limit it to about .94f of the minimum terrain dimension, so:

    maxBrushSize = min(terrainData.size.x, terrainData.size.z) * .94f
     
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