Talk:Biome spread

Walls do not spread biomes.
Confirmed here on forums. --MentalMouse42 (talk) 04:54, 17 August 2019 (UTC)


 * According to the 1.3.5.3 source code, that is not entirely true. Walls do spread, but they only affect natural purity walls. Here is what I found:
 * Natural Corrupt Grass Walls, natural Ebonstone Walls (both regardless of foreground block type – can be none at all), and Corrupt grass can all convert any Grass Wall, Jungle Wall, or Flower Wall (all three natural or manually placed, does not matter) within a radius of 2 tiles to a natural Corrupt Grass Wall, but only if there is at least one Corruption-related block (Demonite Ore, Corrupt grass, Corruption plants/flowers, Vile Mushroom, Ebonstone Block, Corruption Thorny Bush, Ebonsand Block, or Purple Ice Block) within a radius of 20 tiles. Crimson and Hallow seem to be quite similar to that (although Hallow cannot convert Jungle Walls, as it cannot convert any Jungle tiles).
 * There is some... unexpected behavior, though: Above the surface, the Crimson does not have this Crimson-related-block-within-20-tiles restriction, but instead the restriction that there does need to be a Crimson-related block in front of the Crimstone/Crimson Grass Wall. Below the surface, this seems to be true for all three biomes. I am highly skeptical about this, because it would be very arbitrary to let only surface Corruption and Hallow spread quite differently from the rest (or am I missing something here?). I assume an error occurred during decompiling which led to certain variable names being swapped (especially because there is unused, unnecessary code nearby, which would imply behavior like described above – if the variable names were correct).
 * The Underground Desert has a separate spreading mechanism: Natural Ebonsandstone Walls, natural Hardened Ebonsand Walls (both regardless of foreground block type – can be none at all), and Ebonsandstone Blocks can convert any Sandstone Wall, natural Crimsandstone Wall, or natural Pearlsandstone Wall to a natural Ebonsandstone Wall and can convert any natural Hardened Sand Wall, natural Hardened Crimsand Wall, or natural Hardened Pearlsand Wall to a natural Hardened Ebonsand Wall. Both conversions can only happen within a radius of 2 tiles and only if there is any Corruption-related block within a radius of 20 tiles.
 * I would like to get some input on this before adding it to the article, especially regarding what I called "unexpected behavior" above. After doing some more source-digging, I realized that Corruption and Crimson are not actually always as similar as I had thought, but this still seems odd to me. Has anybody experienced something in that regard?
 * --Rye Greenwood (talk) 04:09, 18 August 2019 (UTC)