Rendering an entity within another entity's render

[coolAlias]

I'm working on a spell-casting mob and was thinking I would be clever and just create a fake spell entity within the mob's render class, and render that as appropriate, since I don't actually want to spawn the spell into the world just yet.

 

Anyway, Minecraft doesn't seem to like that so much:

 

java.lang.NullPointerException: Rendering entity in world
at net.minecraft.client.renderer.entity.Render.bindTexture(Render.java:62)
at net.minecraft.client.renderer.entity.Render.bindEntityTexture(Render.java:57)
at zeldaswordskills.client.render.entity.RenderEntityMagicSpell.doRender(RenderEntityMagicSpell.java:55)
at zeldaswordskills.client.render.entity.RenderEntityWizzrobe.doRender(RenderEntityWizzrobe.java:56)
at net.minecraft.client.renderer.entity.RenderManager.func_147939_a(RenderManager.java:300)
at net.minecraft.client.renderer.entity.RenderManager.renderEntityStatic(RenderManager.java:278)
at net.minecraft.client.renderer.entity.RenderManager.renderEntitySimple(RenderManager.java:251)
at net.minecraft.client.renderer.RenderGlobal.renderEntities(RenderGlobal.java:533)
at net.minecraft.client.renderer.EntityRenderer.renderWorld(EntityRenderer.java:1308)
at net.minecraft.client.renderer.EntityRenderer.updateCameraAndRender(EntityRenderer.java:1095)
at net.minecraft.client.Minecraft.runGameLoop(Minecraft.java:1067)
at net.minecraft.client.Minecraft.run(Minecraft.java:961)
at net.minecraft.client.main.Main.main(Main.java:164)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:134)
at net.minecraft.launchwrapper.Launch.main(Launch.java:28)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at GradleStart.bounce(GradleStart.java:107)
at GradleStart.startClient(GradleStart.java:100)
at GradleStart.main(GradleStart.java:65)


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Stacktrace:
at net.minecraft.client.renderer.entity.Render.bindTexture(Render.java:62)
at net.minecraft.client.renderer.entity.Render.bindEntityTexture(Render.java:57)
at zeldaswordskills.client.render.entity.RenderEntityMagicSpell.doRender(RenderEntityMagicSpell.java:55)
at zeldaswordskills.client.render.entity.RenderEntityWizzrobe.doRender(RenderEntityWizzrobe.java:56)

-- Entity being rendered --
Details:
Entity Type: zeldaswordskills.wizzrobe (zeldaswordskills.entity.mobs.EntityWizzrobe)
Entity ID: 70
Entity Name: entity.zeldaswordskills.wizzrobe.name
Entity's Exact location: -104.53, 83.00, 174.50
Entity's Block location: World: (-105,83,174), Chunk: (at 7,5,14 in -7,10; contains blocks -112,0,160 to -97,255,175), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
Entity's Momentum: 0.00, -0.08, 0.00

-- Renderer details --
Details:
Assigned renderer: zeldaswordskills.client.render.entity.RenderEntityWizzrobe@b9902f7
Location: 5.56,-3.62,1.74 - World: (5,-4,1), Chunk: (at 5,-1,1 in 0,0; contains blocks 0,0,0 to 15,255,15), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
Rotation: 88.59375
Delta: 0.1744988
Stacktrace:
at net.minecraft.client.renderer.entity.RenderManager.func_147939_a(RenderManager.java:300)
at net.minecraft.client.renderer.entity.RenderManager.renderEntityStatic(RenderManager.java:278)
at net.minecraft.client.renderer.entity.RenderManager.renderEntitySimple(RenderManager.java:251)
at net.minecraft.client.renderer.RenderGlobal.renderEntities(RenderGlobal.java:533)
at net.minecraft.client.renderer.EntityRenderer.renderWorld(EntityRenderer.java:1308)

 

 

Here is what I tried in the mob's render class:

 

@SideOnly(Side.CLIENT)
public class RenderEntityWizzrobe extends RenderLiving
{
private static final ResourceLocation fireWizzrobeTexture = new ResourceLocation("textures/entity/zombie.png");

private final EntityMagicSpell spell;
private final RenderEntityMagicSpell spellRenderer;

/** Wizzrobe model provides easy means of knowing if spell should be rendered */
private final ModelWizzrobe model;

public RenderEntityWizzrobe(ModelWizzrobe model) {
	super(model, 0.5F);
	this.model = model;
	this.spell = new EntityMagicSpell(Minecraft.getMinecraft().theWorld);
	this.spell.ticksExisted = 0;
	this.spellRenderer = new RenderEntityMagicSpell();
}

@Override
public void doRender(Entity entity, double dx, double dy, double dz, float yaw, float partialTick) {
	super.doRender(entity, dx, dy, dz, yaw, partialTick);
	if (model.atPeak) { // spell should render
		spell.setType(MagicType.WIND);
		++spell.ticksExisted;
		spellRenderer.doRender(spell, dx, dy, dz, yaw, partialTick); // NULL pointer thrown from here, pointing to bindEntityTexture
	} else {
		spell.ticksExisted = 0;
	}
}

@Override
protected ResourceLocation getEntityTexture(Entity entity) {
	return fireWizzrobeTexture; // TODO
}
}

 

 

Here is the RenderEntityMagicSpell class - works fine for real spell entities rendering in the world:

 

@SideOnly(Side.CLIENT)
public class RenderEntityMagicSpell extends Render
{
private final ModelCube box1 = new ModelCube(4);
private final ModelCube box2 = new ModelCube(4);

public RenderEntityMagicSpell() {}

@Override
public void doRender(Entity entity, double dx, double dy, double dz, float yaw, float partialTick) {
	GL11.glPushMatrix();
	GL11.glEnable(GL11.GL_BLEND);
	GL11.glDisable(GL11.GL_LIGHTING);
	GL11.glEnable(GL11.GL_TEXTURE_2D);
	GL11.glBlendFunc(GL11.GL_SRC_ALPHA, GL11.GL_ONE_MINUS_SRC_ALPHA);
	OpenGlHelper.setLightmapTextureCoords(OpenGlHelper.lightmapTexUnit, 240f, 240f);
	GL11.glTranslated(dx, dy, dz);
	GL11.glRotatef(yaw, 0, 1, 0);
	float roll = ((float) entity.ticksExisted + partialTick) * 40;
	while (roll > 360) roll -= 360;
	GL11.glRotatef(roll, 0.8F, 0F, -0.6F);
	bindEntityTexture(entity);
	Tessellator.instance.setBrightness(0xf000f0);
	box1.render(entity);
	GL11.glRotatef(45, 1, 0, 1);
	box2.render(entity);
	GL11.glDisable(GL12.GL_RESCALE_NORMAL);
	GL11.glEnable(GL11.GL_LIGHTING);
	GL11.glDisable(GL11.GL_BLEND);
	GL11.glPopMatrix();
}

@Override
protected ResourceLocation getEntityTexture(Entity entity) {
	return ((EntityMagicSpell) entity).getType().getEntityTexture();
}
}

 

 

Clearly the problem is that Render#bindEntityTexture is not able to get the correct texture, but after going through the stack trace and trying to trace the method calls, I still cannot fathom why.

 

Does anyone have experience doing something like this?

[TheGreyGhost]

Hi

 

I don't have experience doing this, but at the risk of stating the obvious I assume that in net.minecraft.client.renderer.entity.Render.bindTexture(Render.java:62), either renderManager or renderEngine is null?

 

        this.renderManager.renderEngine.bindTexture(p_110776_1_);

 

If you can figure out why that is, you'd be a lot closer..?

 

-TGG

 

[coolAlias]

Ha, you are probably right TGG. Instantiating a render class instance probably doesn't initialize the render manager/engine in any way... hmm. Sometimes it just takes another pair of eyes