[Solved][1.16.5] Issue with rendering texture using Tessellator and BufferBuilder

[MonkeyKnight]

I have coded a little test to experiment with rendering fullscreen overlays for my mod in Minecraft. As it is my first time delving into this kind of rendering, I started off simple, basically copying the renderPumpkin() method but I am having issues. My goal is to render textures that will show up on a player's screen in certain situations. For this test, I just went with the standard pumpkinblur. I used a RenderGameOverlayEvent.Post to trigger the rendering of the pumpkin. Here is my event code:

@EventBusSubscriber(modid = Epidemics.MOD_ID, bus = Bus.FORGE)
public class GuiRenderEvents {

    @SubscribeEvent
    public static void renderGameOverlay(RenderGameOverlayEvent.Post event) {
        if (event.getType() == RenderGameOverlayEvent.ElementType.HOTBAR) {
        	//System.out.println("Event Triggered");
        	new RenderTest(Minecraft.getInstance());
        }
    }
}

I then created a class that extends InGameGUI to render the pumpkin. It almost directly copies the renderPumpkin() method in InGameGUI.

import com.mojang.blaze3d.systems.RenderSystem;

import net.minecraft.client.Minecraft;
import net.minecraft.client.gui.IngameGui;
import net.minecraft.client.renderer.BufferBuilder;
import net.minecraft.client.renderer.Tessellator;
import net.minecraft.client.renderer.vertex.DefaultVertexFormats;

public class RenderTest extends IngameGui{
	
	public RenderTest(Minecraft minecraft) {
		super(minecraft);
		renderTest(minecraft);
	}
	
	private void renderTest(Minecraft minecraft) {
		RenderSystem.disableDepthTest();
		RenderSystem.depthMask(false);
		RenderSystem.defaultBlendFunc();
		RenderSystem.color4f(1.0F, 1.0F, 1.0F, 1.0F);
		RenderSystem.disableAlphaTest();
		minecraft.getTextureManager().bind(PUMPKIN_BLUR_LOCATION);
		Tessellator tessellator = Tessellator.getInstance();
		BufferBuilder bufferbuilder = tessellator.getBuilder();
		bufferbuilder.begin(7, DefaultVertexFormats.POSITION_TEX);
		bufferbuilder.vertex(0.0D, (double)this.screenHeight, -90.0D).uv(0.0F, 1.0F).endVertex();
		bufferbuilder.vertex((double)this.screenWidth, (double)this.screenHeight, -90.0D).uv(1.0F, 1.0F).endVertex();
		bufferbuilder.vertex((double)this.screenWidth, 0.0D, -90.0D).uv(1.0F, 0.0F).endVertex();
		bufferbuilder.vertex(0.0D, 0.0D, -90.0D).uv(0.0F, 0.0F).endVertex();
		tessellator.end();
		RenderSystem.depthMask(true);
		RenderSystem.enableDepthTest();
		RenderSystem.enableAlphaTest();
		RenderSystem.color4f(1.0F, 1.0F, 1.0F, 1.0F);
	}
}

The renderTest() method is being triggered but I do not see anything on my screen. Can you spot where I might have forgotten something?

Edited May 6, 2021 by MonkeyKnight

[MonkeyKnight]

I have a quick update. I have narrowed down the issue to the renderGameOverlay.post event. I changed the code of the renderTest constructor to just trigger the vanilla renderPumpkin() method and there still was no pumpkin face shown.

	public RenderTest(Minecraft minecraft) {
		super(minecraft);
		renderPumpkin();
		/*
		screenWidth = minecraft.getWindow().getGuiScaledWidth();
	    	screenHeight = minecraft.getWindow().getGuiScaledHeight();
		renderTest(minecraft);
		*/
	}

Do you have any suggestions on what I should change in my render event?

[MonkeyKnight]

I have another update! I changed my render event code to this:

@EventBusSubscriber(modid = Epidemics.MOD_ID, bus = Bus.FORGE)
public class GuiRenderEvents {

    @SubscribeEvent
    public static void renderGameOverlay(RenderGameOverlayEvent.Post event) {
        if (event.getType() == RenderGameOverlayEvent.ElementType.HOTBAR) {
        	System.out.println(1);
        	RenderTest render = new RenderTest(Minecraft.getInstance());
        	render.renderTestPumpkin(Minecraft.getInstance());
        }
    }
}

public class RenderTest extends IngameGui{

	private int screenWidth;
	private int screenHeight;
	public RenderTest(Minecraft minecraft) {
		super(minecraft);
		
		screenWidth = minecraft.getWindow().getGuiScaledWidth();
	    screenHeight = minecraft.getWindow().getGuiScaledHeight();
	    /*
		renderTest(minecraft);
		*/
	}
	
	public void renderTestPumpkin(Minecraft minecraft) {
		RenderSystem.disableDepthTest();
		RenderSystem.depthMask(false);
		RenderSystem.defaultBlendFunc();
		RenderSystem.color4f(1.0F, 1.0F, 1.0F, 1.0F);
		RenderSystem.disableAlphaTest();
		minecraft.getTextureManager().bind(PUMPKIN_BLUR_LOCATION);
		Tessellator tessellator = Tessellator.getInstance();
		BufferBuilder bufferbuilder = tessellator.getBuilder();
		bufferbuilder.begin(7, DefaultVertexFormats.POSITION_TEX);
		bufferbuilder.vertex(0.0D, (double)screenHeight, -90.0D).uv(0.0F, 1.0F).endVertex();
		bufferbuilder.vertex((double)screenWidth, (double)screenHeight, -90.0D).uv(1.0F, 1.0F).endVertex();
		bufferbuilder.vertex((double)screenWidth, 0.0D, -90.0D).uv(1.0F, 0.0F).endVertex();
		bufferbuilder.vertex(0.0D, 0.0D, -90.0D).uv(0.0F, 0.0F).endVertex();
		tessellator.end();
		RenderSystem.depthMask(true);
		RenderSystem.enableDepthTest();
		RenderSystem.enableAlphaTest();
		RenderSystem.color4f(1.0F, 1.0F, 1.0F, 1.0F);
	}
}

Now it is showing up n the game, just as a black screen though. Do you know what is causing the black screen?

[MonkeyKnight]

Never mind, it works fine now. I just forgot to blend it.

[eggpasta]

Just now, MonkeyKnight said:

Never mind, it works fine now. I just forgot to blend it.

Can you show what that looks like?

I would like to try this

[MonkeyKnight]

Sure, here are my two classes that I used. 

The render event:

@EventBusSubscriber(modid = Epidemics.MOD_ID, bus = Bus.FORGE)
public class GuiRenderEvents {

    @SubscribeEvent
    public static void renderGameOverlay(RenderGameOverlayEvent.Post event) {
        if (event.getType() == RenderGameOverlayEvent.ElementType.ALL) {
        	System.out.println(1);
        	RenderTest render = new RenderTest(Minecraft.getInstance());
        	render.renderTestPumpkin(Minecraft.getInstance());
        }
    }
}

The renderer:

public class RenderTest extends IngameGui{

	public static final ResourceLocation NEW_PUMPKIN_LOCATION = new ResourceLocation(Epidemics.MOD_ID + ":textures/gui/pumpkinblurtest.png");
	private int screenWidth;
	private int screenHeight;
	public RenderTest(Minecraft minecraft) {
		super(minecraft);
		
		screenWidth = minecraft.getWindow().getGuiScaledWidth();
	    screenHeight = minecraft.getWindow().getGuiScaledHeight();
	}
	
	public void renderTestPumpkin(Minecraft minecraft) {
		RenderSystem.disableDepthTest();
		RenderSystem.enableBlend();
		RenderSystem.depthMask(false);
		RenderSystem.defaultBlendFunc();
		RenderSystem.blendFuncSeparate(SourceFactor.SRC_ALPHA, DestFactor.ONE_MINUS_SRC_ALPHA, SourceFactor.ONE, DestFactor.ZERO);
		RenderSystem.color4f(1.0F, 1.0F, 1.0F, 1.0F);
		RenderSystem.disableAlphaTest();
		minecraft.getTextureManager().bind(NEW_PUMPKIN_LOCATION);
		Tessellator tessellator = Tessellator.getInstance();
		BufferBuilder bufferbuilder = tessellator.getBuilder();
		bufferbuilder.begin(7, DefaultVertexFormats.POSITION_TEX);
		bufferbuilder.vertex(0.0D, (double)screenHeight, -90.0D).uv(0.0F, 1.0F).endVertex();
		bufferbuilder.vertex((double)screenWidth, (double)screenHeight, -90.0D).uv(1.0F, 1.0F).endVertex();
		bufferbuilder.vertex((double)screenWidth, 0.0D, -90.0D).uv(1.0F, 0.0F).endVertex();
		bufferbuilder.vertex(0.0D, 0.0D, -90.0D).uv(0.0F, 0.0F).endVertex();
		tessellator.end();
		RenderSystem.depthMask(true);
		RenderSystem.enableDepthTest();
		RenderSystem.enableAlphaTest();
		RenderSystem.color4f(1.0F, 1.0F, 1.0F, 1.0F);
	}
}