[1.6.4] Item Render on top of block when placed on block

[Xcox123]

First, sorry for the bad title, couldn't think of how to word it

 

Basically, what I want is, that when I right click a block with any item, the item renders (maybe spinning if thats possible) on top of the block. An example of this is in Thaumcraft's infusion alter. When you right click an item onto it, to renders on top of it, but isn't a pickupable entity.

 

Anyone got a suggestion for how I should go about doing this?

[TheGreyGhost]

Hi

 

From a rendering point of view, vanilla does this already when you drop items- creates an EntityItem.

 

You could use a TileEntitySpecialRenderer for the block which holds its own EntityItem (so that the player can't pick it up) and renders it.

 

-TGG

[MrArcane111]

First off, why are you still coding for 1.6.4? Use 1.7.2!

 

Secondly, to render an item:

 

Minecraft mc = Minecraft.getMinecraft();

GL11.glTranslatef(8, 0, 0);
float scale = 1.9F;
GL11.glScalef(scale, scale, scale);
float angle = mc.theWorld.getWorldTime() * 11.6F;
GL11.glRotatef(angle, 0 - 0.5F, 0 - 0.5F, 0);

if (is != null)
{
mc.renderEngine.bindTexture(TextureMap.locationItemsTexture);
int renderPass = 0;

do
{
	IIcon icon = Items.ender_eye.getIcon(item, renderPass);

	if (icon != null)
	{
		float minU = icon.getMinU();
		float maxU = icon.getMaxU();
		float minV = icon.getMinV();
		float maxV = icon.getMaxV();
		ItemRenderer.renderItemIn2D(Tessellator.instance, maxU, minV, minU, maxV, icon.getIconWidth(), icon.getIconHeight(), 1.0F / 16.0F);
		GL11.glColor3f(1.0F, 1.0F, 1.0F);
	}

	renderPass++;
} while (renderPass < is.getItem().getRenderPasses(is.getItemDamage()));
}

 

You will need to adjust the icon and GL scales/translations --I basically just ripped this out of my Ender Glove code. This will render any item that you want with a thickness (default is 0.0625F). As an added bonus, this also rotates said item around various axes --adjust as you see fit. You will have to adjust this method for blocks. Good luck!

[Xcox123]

Thanks!!!

 

I know this is prob a noob question(sorry) but what is "is" ("while (renderPass < is.getItem().getRenderPasses(is.getItemDamage()));")

[Xcox123]

I feel like a dick for this but ~Bump

 

[TheGreyGhost]

Thanks!!!

 

I know this is prob a noob question(sorry) but what is "is" ("while (renderPass < is.getItem().getRenderPasses(is.getItemDamage()));")

 

Hi

 

To be honest, I don't think you need to do all of that manually since vanilla does it for you, and handles all the special cases too (eg items which are 3D, items which have multiple render passes (eg potions) etc.)

Step (1) create an EntityItem from your item

            EntityItem entityitem = new EntityItem(world, xPosition, yPosition, zPosition, itemStack);

  Store it somewhere (in your TileEntity), don't spawn it

Step (2) in your TileEntitySpecialRenderer for the TileEntity, render the EntityItem

    renderItem.doRender(itemStack, xPos, yPos, zPos, 0, partialTick);

where

renderItem is a RenderItem() you have created and stored previously, and partialTick should be available from your TESR method, otherwise set it to 0.

 

Step (3) in your tileEntity.updateEntity(), animate the item

entityItem.age++;

 

There are several tutorials around on how to create TileEntity and TileEntitySpecialRenderer, if you're not sure how to do that.

 

You may need to set up some of the lighting configurations / OpenGL settings before the call to the doRender, but we can cross that bridge when we come to it

 

-TGG

 

 

 

 

 

 

 

 

 

 

 

 

 

[Xcox123]

First off, why are you still coding for 1.6.4? Use 1.7.2!

 

Secondly, to render an item:

 

Minecraft mc = Minecraft.getMinecraft();

GL11.glTranslatef(8, 0, 0);
float scale = 1.9F;
GL11.glScalef(scale, scale, scale);
float angle = mc.theWorld.getWorldTime() * 11.6F;
GL11.glRotatef(angle, 0 - 0.5F, 0 - 0.5F, 0);

if (is != null)
{
mc.renderEngine.bindTexture(TextureMap.locationItemsTexture);
int renderPass = 0;

do
{
	IIcon icon = Items.ender_eye.getIcon(item, renderPass);

	if (icon != null)
	{
		float minU = icon.getMinU();
		float maxU = icon.getMaxU();
		float minV = icon.getMinV();
		float maxV = icon.getMaxV();
		ItemRenderer.renderItemIn2D(Tessellator.instance, maxU, minV, minU, maxV, icon.getIconWidth(), icon.getIconHeight(), 1.0F / 16.0F);
		GL11.glColor3f(1.0F, 1.0F, 1.0F);
	}

	renderPass++;
} while (renderPass < is.getItem().getRenderPasses(is.getItemDamage()));
}

 

You will need to adjust the icon and GL scales/translations --I basically just ripped this out of my Ender Glove code. This will render any item that you want with a thickness (default is 0.0625F). As an added bonus, this also rotates said item around various axes --adjust as you see fit. You will have to adjust this method for blocks. Good luck!

 

I am using this code in the onBlockActivated method, but whenever I right click the block, it gives the following crash error:  java.lang.RuntimeException: No OpenGL context found in the current thread.

 

I have no experience at all with OpenGL, anyone got a suggestion?

[TheGreyGhost]

Hi

 

Two things

i) the error is because onBlockActivated is called on the server as well as the client.  in onBlockActivated, use par2World.isRemote() to tell the difference. 

ii) putting the render code into onBlockActivated is not going to do what you want.

 

your render code will get called every time the block (TileEntity) is rendered.  onBlockActivated is only called once.

your onBlockActivated needs to update your TileEntity with the new item, so that when the renderer for TileEntity is called, it displays the item you clicked.

 

I suggest you get the rendering working first and worry about the onBlockActivated later.

 

-TGG

[Xcox123]

Thanks for the help

 

So should I put the render code into the TileEntity class that I have?

 

I have moved my code into the only class that extends TileEntitySpecialRenderer, which is my Render class for my custom model. I am currently calling it in onBlockActivated, with a if(!world.isRemote)to open the gui and then a if(player.getCurrentEquippedItem() != null) to detect if theres an item in hand. If there is, it runs the render code.

 

So where should I call my render code if onBlockActivated is bad?

 

[TheGreyGhost]

Thanks for the help

 

So should I put the render code into the TileEntity class that I have?

 

I have moved my code into the only class that extends TileEntitySpecialRenderer, which is my Render class for my custom model. I am currently calling it in onBlockActivated, with a if(!world.isRemote)to open the gui and then a if(player.getCurrentEquippedItem() != null) to detect if theres an item in hand. If there is, it runs the render code.

 

So where should I call my render code if onBlockActivated is bad?

Hi

 

Your render code should go into your TileEntitySpecialRenderer for your TileEntity: the renderTileEntityAt for your TESR should call a "whatIsMyDisplayedItem()" method on the TileEntity to retrieve the Item being displayed, then render the displayed item.

 

Your block.onBlockActivated should retrieve the TileEntity at that location (World.getBlockTileEntity) and call your "changeDisplayedItem()" method on it.  Later, when the TESR calls whatIsMyDisplayedItem(), it will then receive the new Item.

 

Do you know how to register your TileEntity and TESR?  Also, if you want the TileEntity to remember your displayed item after saving & reloading the world - the NBT functions readFromNBT and writeToNBT?

 

-TGG