I am a tutorial-reading, source-code-speculating newb, so pardon my ignorance.

 

When I try to make a block plant something, the plant appears, but as soon as I interact with it (right-click, left-click, etc.), it disappears.  I hope that this is a problem that you veterans are familiar with, because I have no real idea what's going on.

 

I want to make a version of a dropper that plants on tilled soil.  To do this, I made a block, extended the dropper class, and overwrote the dispense method. 

 

In the method, I call the onItemUse method of the seeds, and according to a println, the 'player', ' x' ,'y' ,'z' , and 'direction' of the onItemUse call are the same as when I do it myself (manually planting still works).

 

here is what I added to the dispense method.

                	//first, we parasitically use the first player in the world list.
                	//(change this later)
                	World world=Minecraft.getMinecraft().theWorld;
                	int tarx=x + Facing.offsetsXForSide[i1],
                		tary=y + Facing.offsetsYForSide[i1],
                		tarz=z + Facing.offsetsZForSide[i1];
                	float	f1=1, f2=1, f3=1;
                	boolean used = false;
                    if (world.playerEntities.size()>0)
                    {
                    	EntityPlayer oddballPlayer = (EntityPlayer) world.playerEntities.get(0);
                		used = itemstack.getItem().onItemUse(itemstack, oddballPlayer, world, tarx, tary, tarz, 1, f1, f2, f3);
                    	if (used){
                			System.out.println("I PLANTED!");
                		}else{
                			System.out.println("I tried...");
                		}
                	}

                    if (used){
                    	itemstack1 = itemstack.copy();

                    	if (--itemstack1.stackSize == 0)
                    	{
                    		itemstack1 = null;
                    	}	
                    }else{
                    	itemstack1 = getBehaviorForItemStack(itemstack).dispense(blocksourceimpl, itemstack);
                    }

 

the full class is here:

http://pastebin.com/2cQKdpGE

//first, we parasitically use the first player in the world list.
                	//(change this later)
                	World world=Minecraft.getMinecraft().theWorld;

You need to change that now. It is client-side only, while placing blocks is server side.

You need to change that now.

 

Thanks GoToLink!

 

I wondered if this was some client/server thing, but as I said, I'm new, and I really don't know how the client/server thing works.  If you have any advice on learning the client/server thing, I'll eat it up, but if not, I'm sure I can figure it out somewhere else.

Hi

 

This link might help with some of the background understanding..

http://greyminecraftcoder.blogspot.com.au/p/list-of-topics.html

In particular the first four topics, plus Minecraft Game Loop, plus "How Forge starts up your code", plus "Client <--> Server communication"

 

-TGG