Is there a way of tweaking some vanilla class:
I want to, change this code from Level.class (World.class on 1.16.x i think)

public abstract class Level extends net.minecraftforge.common.capabilities.CapabilityProvider<Level> implements LevelAccessor, AutoCloseable, net.minecraftforge.common.extensions.IForgeLevel {
...
public boolean isRainingAt(BlockPos p_46759_) {
      if (!this.isRaining()) {
         return false;
      } else if (!this.canSeeSky(p_46759_)) {
         return false;
      } else if (this.getHeightmapPos(Heightmap.Types.MOTION_BLOCKING, p_46759_).getY() > p_46759_.getY()) {
         return false;
      } else {
         Biome biome = this.getBiome(p_46759_);
         return biome.getPrecipitation() == Biome.Precipitation.RAIN && biome.getTemperature(p_46759_) >= 0.15F;
      }
}
  ... }

what i want to do is, make the rain stop or start on specific area (or better change climate).
Biome's climate settings(temperature, humidity) can be changed, but i think only once, on world generation, I think

source: [1.17.1]
net.minecraft.world.level;
net.minecraft.world.level.biome;
net.minecraftforge.event.world.BiomeLoadingEvent;

im nowhere near what im trying to do... but if anyone has an idea how to achieve it, or anything similar, any help is appreciated :3

can the class be replaced with extention???

hi, it's u again 😅
so i shouldn't change it... (regardless of compatibility with other mods)

how about anything with similar result, any idea...

im trying to add monsoon and season

Mixins? https://github.com/SpongePowered/Mixin/wiki/Introduction-to-Mixins---Understanding-Mixin-Architecture#2-through-the-looking-glass

19 minutes ago, diesieben07 said:

Not in a supported way.

hi, it's u again 😅
so i shouldn't change it... (regardless of compatibility with other mods)

how about anything with similar result, any idea...

im trying to add monsoon and season

3 minutes ago, than00ber1 said:

Mixins? https://github.com/SpongePowered/Mixin/wiki/Introduction-to-Mixins---Understanding-Mixin-Architecture#2-through-the-looking-glass

ohhhhh look interesting. ill read first. anyway thanks!

3 hours ago, diesieben07 said:

Mixins / Coremods are not a supported practice here.

oh, oki. thanks anyways

you could ask on the Forge discord server  in the channel #non-api-modding (there are the experts about Mixins/Coremods)