Essentially, I'm trying to recreate particles as entities. The main reason I'm trying to do this is so I can use Entity's onImpact() method to do server-side things, like setting an entity on fire (whereas particles are client-side).

 

In order to render these 2D entities, do I need to:

[*]Use an item-based renderer and create a new item for every particle (like every vanilla ThrowableEntity does)

[*]Use a model-based renderer and create a model (that I would probably have to make 2D and always face the player)

Or is there a way to render a texture in 2D without using an item or model?

You'd do #2 sort of, except that you would manually interface with the tessellator to draw your camera-facing quad.  Take a look at how nametags are drawn.

Oh god... I am too damn lazy to explain everything about renderers, so... Catch!

 

/**
* @author Ernio
*/
@SideOnly(Side.CLIENT)
public class RenderThrowable extends Render
{
ResourceLocation rl = new ResourceLocation(ModID + ":" + "textures/something/" + "test" + ".png");

public RenderThrowable(RenderManager rm)
{
	super(rm);
}

public void doRender(EntityThrowable entity, double x, double y, double z, float f, float partialTicks)
{
	GlStateManager.pushMatrix();
	GlStateManager.translate((float) (x), (float) (y), (float) (z));
	GlStateManager.enableRescaleNormal();
	GlStateManager.rotate(-this.renderManager.playerViewY, 0.0F, 1.0F, 0.0F);
	GlStateManager.rotate(this.renderManager.playerViewX, 1.0F, 0.0F, 0.0F);
	GL11.glScalef(entity.getScale(), entity.getScale(), entity.getScale());
	this.bindEntityTexture(entity);
	float fix = 0.00390625F;
	int xOffset = (entity.getIconIndex() % 16) * 16;
	int yOffset = (entity.getIconIndex() % 256) * 16;
	Tessellator tess = Tessellator.getInstance();
	WorldRenderer wr = tess.getWorldRenderer();
	wr.startDrawingQuads();
	wr.setNormal(0.0F, 1.0F, 0.0F);
	wr.addVertexWithUV((-0.5F), (0.6F), 0.0F, (xOffset + 0) * fix, (yOffset + 16) * fix);
	wr.addVertexWithUV((0.5F), (0.6F), 0.0F, (xOffset + 16) * fix, (yOffset + 16) * fix);
	wr.addVertexWithUV((0.5F), (-0.4F), 0.0F, (xOffset + 16) * fix, (yOffset + 0) * fix);
	wr.addVertexWithUV((-0.5F), (-0.4F), 0.0F, (xOffset + 0) * fix, (yOffset + 0) * fix);
	tess.draw();
	GlStateManager.disableRescaleNormal();
	GlStateManager.popMatrix();

	super.doRender(entity, x, y, z, f, partialTicks);
}

protected ResourceLocation getResource(EntityThrowable entity)
{
	return rl;
}

@Override
protected ResourceLocation getEntityTexture(Entity entity)
{
	return this.getResource((EntityThrowable) entity);
}

@Override
public void doRender(Entity entity, double x, double y, double z, float f, float partialTicks)
{
	this.doRender((EntityThrowable) entity, x, y, z, f, partialTicks);
}
}

 

ClientProxy#init():

RenderingRegistry.registerEntityRenderingHandler(CustomEntityThrowable.class, new RenderThrowable(Minecraft.getMinecraft().getRenderManager()));

 

And btw - this shit right there is badlwy written. I could fix some things, but again - I am lazy.

 

As to what it does - it literally grabs ResourceLocation provided and renders it FLAT (2d) in center of entity facing player.

 

Note that this system is designed to grab 16x16 textures from 256x256 sheet (ResourceLocation) on index based on:

int xOffset = (entity.getIconIndex() % 16) * 16;
int yOffset = (entity.getIconIndex() % 256) * 16;

 

So go figure

 

To do it for items (grap item texture) look at ItemRenderer classes. Also - for it to work with item (and not pure RL like above), yo uwill need to put texture in texture sheet using TextureStitchEvent (or whatver).