public class KnowledgeClientProxy extends CommonProxy {

	public void registerRenderInfo() {

		 ClientRegistry.bindTileEntitySpecialRenderer(TileEntityThaumTank.class, new TileEntityThaumTankRenderer());
		 MinecraftForgeClient.registerItemRenderer(Item.getItemFromBlock(TKBlocks.thaumTank), new ThaumTankItemRenderer());
	}
}










public class ThaumTankItemRenderer implements IItemRenderer {

	private static RenderItem renderItem = new RenderItem();

    @Override
    public boolean handleRenderType(ItemStack itemStack, ItemRenderType type) {
            return type == ItemRenderType.INVENTORY;
    }

    @Override
    public boolean shouldUseRenderHelper(ItemRenderType type, ItemStack item,
                    ItemRendererHelper helper) {
            return false;
    }

    @Override
    public void renderItem(ItemRenderType type, ItemStack itemStack, Object... data) {
            FontRenderer fontRenderer = Minecraft.getMinecraft().fontRenderer;

            // ====================== Render item texture ======================
            IIcon icon = itemStack.getIconIndex();
            renderItem.renderIcon(0, 0, icon, 16, 16);

            // ====================== Render OpenGL square shape ======================
            GL11.glDisable(GL11.GL_TEXTURE_2D);
            GL11.glEnable(GL11.GL_BLEND);
            GL11.glDepthMask(false);
            GL11.glBlendFunc(GL11.GL_SRC_ALPHA, GL11.GL_ONE_MINUS_SRC_ALPHA);

            Tessellator tessellator = Tessellator.instance;
            tessellator.startDrawing(GL11.GL_QUADS);
            tessellator.setColorRGBA(0, 0, 0, 128);
            tessellator.addVertex(0, 0, 0);
            tessellator.addVertex(0, 8, 0);
            tessellator.addVertex(8, 8, 0);
            tessellator.addVertex(8, 0, 0);
            tessellator.draw();

            GL11.glDepthMask(true);
            GL11.glDisable(GL11.GL_BLEND);

            // ====================== Render text ======================
            GL11.glEnable(GL11.GL_TEXTURE_2D);
            String text = Integer.toString(itemStack.getItemDamage());
            fontRenderer.drawStringWithShadow(text, 1, 1, 0xFFFFFF);
    }

}