Hello,

I am working on an GUI for a Block (in 1.12.2) and want the background to be drawn considering the Alphachannel.

It worked like this :

@Override
	protected void drawGuiContainerBackgroundLayer(float partialTicks, int mouseX, int mouseY) {
		
		int i = (this.width - this.xSize) / 2;
		int j = (this.height - this.ySize) / 2;
		
		Minecraft.getMinecraft().getTextureManager().bindTexture(texture);
		
		GlStateManager.color(1.0F, 1.0F, 1.0F, 0.7F);
		
		drawTexturedModalRect(i, j, 0, 0, xSize, ySize);
		
		GlStateManager.color(1.0F, 1.0F, 1.0F, 1.0F);
	
	}

 

But I had to discover, that if I or a commandblock write something in the chat the background is drawn without transparency as long as the chat is visible.

After the chat disappears it changes back.

 

I am not enough into minecrafts intern rendering processes to understand what minecraft is doing here.

Could anyone help me with that?

Edited November 16, 20195 yr by Eisenpaulchen

Call GuiContainer#drawDefaultBackground to draw the background.

Ok I did that but that was just a formal suggestion?

It unfortunatly did not fix it.

As you can imagine it looks now like this :

@Override
	public void drawDefaultBackground() {
		
		int i = (this.width - this.xSize) / 2;
		int j = (this.height - this.ySize) / 2;
		
		Minecraft.getMinecraft().getTextureManager().bindTexture(texture);
		
		GlStateManager.color(1.0F, 1.0F, 1.0F, 0.7F);
		
		drawTexturedModalRect(i, j, 0, 0, xSize, ySize);
		
		GlStateManager.color(1.0F, 1.0F, 1.0F, 1.0F);
	}

plus the call in

drawScreen()

 

like this :

 

@Override
	public void drawScreen(int mouseX, int mouseY, float partialTicks) {
		drawDefaultBackground();
		...
	}

 

Ok I did some research my self in the Minecraft Sourcecode and I found a possible solution:

 

In Minecrafts method for rendering the chat called 

drawChat()

The method

GlStateManager.disableBlend();

is called.

 

As one can see in this OpenGl Wiki article this is what took the transparency from my background as long as the chat is visible.

 

Therefore I fixed it like this:

GlStateManager.color(1.0F, 1.0F, 1.0F, 0.7F);
		
GlStateManager.enableBlend();
		
drawTexturedModalRect(i, j, 0, 0, xSize, ySize);
		
GlStateManager.disableBlend();

GlStateManager.color(1.0F, 1.0F, 1.0F, 1.0F);

 

Hope this is the or at least one right way to do this. If this is not the case please tell me.

4 hours ago, Eisenpaulchen said:

Hope this is the or at least one right way to do this.

It is indeed.