How do I map a texture onto an Entity in a Minecraft Plugin - minecraft

Question

I'm trying to write a plugin to brand cattle and thought it would be pretty easy, but I'm stuck looking for the information that would help me do this.
Where can I find information that will help me map a texture (from a png, for example) onto an Entity. While there's information about built-in textures for Players etc, I haven't found a resource that would help me understand how I could get something to render on the side of an Entity.
I'm guessing that I'd use something like the following calls...
Minecraft.getMinecraft().renderEngine.bindTexture(new ResourceLocation("tc:textures/gui/my-icon.png"));
Minecraft.getMinecraft().ingameGUI.drawTexturedModalRect(etc);
Not certain how I'd enforce them into the drawing of a cow or a horse.

Answer 1

This isn't possible while using Bukkit, since Bukkit is server-side and can't change textures. There's one exception, though: Servers can send players resource packs. However, there does not appear to be a way to create a unique texture based off of any data, so you'd have to make all cows look the same. It wouldn't really do what you want. (Players are another exception, but protocol-wise, their skins are arbitrary anyways).
However, if you want to use Minecraft Forge, this is far more manageable. You can subclass the entity and change some of the rendering code. Perhaps you can also have an item of some sort (a branding iron, maybe) to convert existing cows into branded cows (they would still spawn as normal cows). I'm not too much of a Forge dev, but something like this should work (though I haven't tested it). This is more of an outline; things like converting the entity and creating an item I'll leave to you.
Here's a basic outline for an entitiy that tracks a texture between the server and the client:
import net.minecraft.entity.passive.EntityCow;
import net.minecraft.util.ResourceLocation;
public class EntityBrandedCow extends EntityCow {
#Override
protected void entityInit() {
super.entityInit();
// Data watcher lets you track data between the server and client
// without handling packets yourself
// http://wiki.vg/Entities
this.dataWatcher.addObject(14, "minecraft:textures/entity/cow/cow.png");
}
public void setTexture(ResourceLocation texture) {
this.dataWatcher.updateObject(14, texture.toString());
}
public ResourceLocation getTexture() {
return new ResourceLocation(this.dataWatcher.getWatchableObjectString(14));
}
}
You'll need to register a custom renderer for your new entity. This would go in the client proxy.
RenderingRegistry.registerEntityRenderingHandler(EntityBrandedCow.class, new RenderBrandedCow(Minecraft.getRenderManager(), new ModelCow(), .7f));
And here's such a render you can use:
import net.minecraft.util.ResourceLocation;
import net.minecraft.client.model.ModelBase;
import net.minecraft.entity.Entity;
import net.minecraft.client.model.ModelBase;
import net.minecraft.client.renderer.entity.RenderLiving;
import net.minecraft.client.renderer.entity.RenderManager;
public class RenderBrandedCow extends RenderLiving {
public RenderBrandedCow(RenderManager manager, ModelBase model, float shadowSize) {
super(manager, model, shadowSize);
}
#Override
protected ResourceLocation getEntityTexture(Entity entity) {
return ((EntityBrandedCow)entity).getTexture();
}
}
That renderer only changes the texture, and doesn't actually overlay anything. This, among other things, means that texture packs won't change branded cows without creating additional textures. An alternative would be to create a second layer. (This is based off of the way sheep wool works - see net.minecraft.client.renderer.entity.layers.LayerSheepWool and net.minecraft.client.renderer.RenderSheep). You can change the renderer to this:
import net.minecraft.client.model.ModelBase;
import net.minecraft.client.renderer.entity.RenderLiving;
import net.minecraft.client.renderer.entity.RenderManager;
public class RenderBrandedCow extends RenderCow {
public RenderBrandedCow(RenderManager manager, ModelBase model, float shadowSize) {
super(manager, model, shadowSize);
this.addLayer(new LayerCowBrand(this));
}
}
And here's the start of some kind of layer rendering code. This won't work on its own; you'll need to write a ModelBrand (see ModelSheep1 for the basis of that).
public class LayerCowBrand implements LayerRenderer {
private final BrandedCowRenderer renderer;
private final ModelBrand model = new ModelBrand();
public LayerCowBrand(BrandedCowRenderer renderer) {
this.renderer = renderer;
}
public void doRenderLayer(EntityBrandedCow entity, float p_177162_2_, float p_177162_3_, float p_177162_4_, float p_177162_5_, float p_177162_6_, float p_177162_7_, float p_177162_8_) {
// It's common to write a second method with the right parameters...
// I don't know off my hand what the parameters here are.
this.renderer.bindTexture(entity.getTexture());
this.model.setModelAttributes(this.sheepRenderer.getMainModel());
this.model.setLivingAnimations(p_177162_1_, p_177162_2_, p_177162_3_, p_177162_4_);
this.model.render(p_177162_1_, p_177162_2_, p_177162_3_, p_177162_5_, p_177162_6_, p_177162_7_, p_177162_8_);
}
public boolean shouldCombineTextures() {
// I don't know
return true;
}
public void doRenderLayer(EntityLivingBase p_177141_1_, float p_177141_2_, float p_177141_3_, float p_177141_4_, float p_177141_5_, float p_177141_6_, float p_177141_7_, float p_177141_8_) {
// This is the actual render method that implements the interface.
this.doRenderLayer((EntityBrandedCow)p_177141_1_, p_177141_2_, p_177141_3_, p_177141_4_, p_177141_5_, p_177141_6_, p_177141_7_, p_177141_8_);
}
}
Hopefully this at least lets you get started. As I said, I'm not a forge dev, but this should be the basics. If you want to ask more questions about forge, post here on Stack Overflow using minecraft-forge (Gaming Stack Exchange also has a minecraft-forge tag but that's for mod usage, not development).