Modern Beta for Forge 1.12.2

A quick hotfix patch. The 1.5.0.0 patch notes have been copied below.

• Fix a datafixer issue that disallowed older Modern Beta worlds with default settings from loading.

1.5.0.0 marks the release of another major version. Please back up your world, just in case, if you wish to update this version.

• Add map previewer, accessed from the world customization GUI.
  • The map previewer will generate a rough terrain/biome map centered on 0/0 based on currently selected settings.
  • If no world seed has been set, then a new random seed will be used for each generation. You can select the displayed seed to copy it to clipboard.
• Add multiple generation subtypes for the Release chunk source, under the layerType generator setting. The types added are:
  • Vanilla: Default, original generation.
  • Continental: Large continents and even larger oceans. Resembles world generation from Minecraft 1.6.4 and earlier.
  • Islands: Large islands with smaller islands interspersed.
  • Small Islands: Like the Islands preset, but with smaller islands only.
  • Pangaea: A single large continent at the center of the world, with smaller islands in the ocean beyond it.
• Add layerSize generator setting, which disconnects the biomeSize setting previously used to set both the terrain size and biome size of the Release chunk and biome sources, respectively.
  • layerSize now controls just terrain size when using the Release chunk source.
  • biomeSize is still used to control biome size when using the Release biome source.
  • Existing worlds will be updated to use the new setting.
• Rework world customization GUI. Page navigation buttons have been removed and replaced with a tab-like interface.
• Add chunk source settings page/tab to world customization GUI and move certain settings to that page.
• Adjust the biome distribution for Release biome source. Previously cold/icy climates were very common and hot climates very rare. The distribution has been adjusted to be more equal. This will affect biome distribution in new chunks for existing worlds with these settings, sorry!
• Fix an incompatibility with JEID/REID.

Technical Changes:

• Add getBaseHeight and getHeightVariation methods to NoiseBiomeSource.
• Add generatesBeaches method to SurfaceBuilder which is used by the map previewer to indicate whether to draw beaches.
• Change GuiPredicate to consume a built ModernBetaGeneratorSettings object instead of its factory.
• Remove a bunch of methods from ChunkSource.
• Remove the World parameter from several methods in ChunkSource.
• Rearrange multiple API packages.