Some Ghost-Block-Rendering Related Questions [1.12.2]

[Tschipp]

I'm trying to render ghost blocks (partially transparent blocks), but I am having some minor issues.

 

Issue #1:

Stained glass is rendered as a plain Color/Solid blocks aren't rendered as transparent:

Code:

			double d0 = player.lastTickPosX + (player.posX - player.lastTickPosX) * event.getPartialTicks();
			double d1 = player.lastTickPosY + (player.posY - player.lastTickPosY) * event.getPartialTicks();
			double d2 = player.lastTickPosZ + (player.posZ - player.lastTickPosZ) * event.getPartialTicks();

			IBlockState stateToRender = LinearHelper.getState(player);

			Minecraft.getMinecraft().renderEngine.bindTexture(TextureMap.LOCATION_BLOCKS_TEXTURE);
			BlockRendererDispatcher renderer = Minecraft.getMinecraft().getBlockRendererDispatcher();

			GlStateManager.pushMatrix();
			GlStateManager.enableBlend();
			GlStateManager.blendFunc(GL11.GL_CONSTANT_ALPHA, GL11.GL_ONE_MINUS_CONSTANT_ALPHA);

			for (BlockPos toPlace : positions) //positions is just a Collection filled with BlockPos
			{
				GlStateManager.pushMatrix();
				GlStateManager.translate(-d0, -d1, -d2);
				GlStateManager.translate(toPlace.getX(), toPlace.getY(), toPlace.getZ());
				GlStateManager.rotate(-90, 0f, 1f, 0f);
				GL14.glBlendColor(1f, 1f, 1f, 0.8f);
				renderer.renderBlockBrightness(stateToRender, 1f);
				GlStateManager.popMatrix();
			}

			GlStateManager.disableBlend();
			GlStateManager.popMatrix();
		

 

I've also tried changing the blend Function to 

			GlStateManager.blendFunc(GL11.GL_SRC_ALPHA, GL11.GL_ONE_MINUS_SRC_ALPHA);

That solved the issue of glass transparency, but it also removed the transparency of other solid blocks:

To be honest, I don't exactly understand what the Blend functions do. If someone could enlighten me, I would be very happy.

 

Issue #2:

The second issue is probably closely related to the first one. The preview-block (the block that gets rendered next to the cursor) is also rendered as a flat Color.

Code:

			RenderHelper.enableGUIStandardItemLighting();
			GlStateManager.pushMatrix();

			Minecraft.getMinecraft().getRenderItem().renderItemAndEffectIntoGUI(stack, (int) (res.getScaledWidth() / 2 + (2.3 * res.getScaleFactor())), (int) (res.getScaledHeight() / 2 - (2.4 * res.getScaleFactor())));

			GlStateManager.popMatrix();
			RenderHelper.disableStandardItemLighting();

 

Issue #3:

At some positions in the world (and always at the same positions), the blockface of a partially transparent block gets rendered.

It shouldn't render that blockface, it should behave like glass when it's placed down.

The code is the same as for Issue #1.

I'm really not sure why it happens, and it always happens at the same spots in the same world. As far as I can tell, nothing is special about these positions, they aren't adjacent to chunkborders or anything.

[Big_Bad_E]

Wait, so by ghost blocks are they just a little transparent?

 

If so shouldn't you set the block to not be an opaque cube?

 

If that's not what you're trying to do, then please make it a bit cleared, I'm having some trouble understanding your thought process.

[Tschipp]

That's not what I'm trying to do. I'm trying to render a solid block (like planks) slightly transparent, and I also want to render stained glass, just with a bit extra transparency applied to the already existing transparency of the block.

[Animefan8888]

48 minutes ago, Tschipp said:

That solved the issue of glass transparency, but it also removed the transparency of other solid blocks:

If one works for one and another works for the other one, check if the block is opaque and use the one that works for that.

[Big_Bad_E]

27 minutes ago, Tschipp said:

That's not what I'm trying to do. I'm trying to render a solid block (like planks) slightly transparent, and I also want to render stained glass, just with a bit extra transparency applied to the already existing transparency of the block.

I'd suggest not to call OpenGL, and instead make a custom item and set the BakedModel to the target BakedModel, but with the texture slightly more opaque.

For help on getting the texture and displaying it, I'd check out the SecretRoomsMod's GitHub.

[Animefan8888]

@Tschipp Under what conditions are you rendering, is this for a block that your mod makes or just as a placement identifier?

[Tschipp]

@Animefan8888 It's a placement identifier

 

33 minutes ago, Animefan8888 said:

If one works for one and another works for the other one, check if the block is opaque and use the one that works for that.

Yes, I guess that would kinda work, but the glass would then just have the standard transparency that it already has, and it wouldn't be decreased

 

Edited August 4, 2018 by Tschipp

[Animefan8888]

Just now, Tschipp said:

@Animefan8888 It's a placement identifier

That's what I thought did you try what I suggested above?

[Tschipp]

2 minutes ago, Animefan8888 said:

That's what I thought did you try what I suggested above?

Yes, see edit above

[Animefan8888]

8 minutes ago, Tschipp said:

Yes, see edit above

Try using this instead.

GlStateManager.tryBlendFuncSeparate(GlStateManager.SourceFactor.SRC_ALPHA, GlStateManager.DestFactor.ONE_MINUS_SRC_ALPHA, GlStateManager.SourceFactor.ONE, GlStateManager.DestFactor.ZERO);

Also switch to using GLStateManager instead of direct OpenGL calls.

[Tschipp]

7 hours ago, Animefan8888 said:

Try using this instead.

GlStateManager.tryBlendFuncSeparate(GlStateManager.SourceFactor.SRC_ALPHA, GlStateManager.DestFactor.ONE_MINUS_SRC_ALPHA, GlStateManager.SourceFactor.ONE, GlStateManager.DestFactor.ZERO);

 

I tried it, but sadly the solid blocks like wood are still not transparent... The solution you suggested above might be the best one.

Quote

Also switch to using GLStateManager instead of direct OpenGL calls.

do you mean this statement?

GL14.glBlendColor(1f, 1f, 1f, 0.8f);

I replaced it with this

GlStateManager.color(1f, 1f, 1f, 0.8f);

but that didn't change anything.

[Animefan8888]

23 minutes ago, Tschipp said:

I replaced it with this

GlStateManager.color(1f, 1f, 1f, 0.8f);

but that didn't change anything.

You do this because it is what Minecraft uses, directly calling OpenGL could mess with the GLStateManager.

25 minutes ago, Tschipp said:

I tried it, but sadly the solid blocks like wood are still not transparent... The solution you suggested above might be the best one.

Maybe, but does it work with the glass completely?

[Tschipp]

I get the default transparency that the glass block has, but I can’t go any lower than that

[Cadiboo]

http://lessie2d.tumblr.com/post/28673280483/opengl-blend-function-cheat-sheet-well-this-is

 

https://www.andersriggelsen.dk/glblendfunc.php

 

Have a look at those, but you’ll be doing a lot of work by trial & error in the debugger.

 

feel free to look at all my rendering code here

https://github.com/Cadiboo/WIPTech/blob/master/src/main/java/cadiboo/wiptech/client/render/tileentity/TESRAssemblyTable.java

(Hologram part)

 

https://github.com/Cadiboo/WIPTech/blob/master/src/main/java/cadiboo/wiptech/util/Utils.java

(renderStackWithColor and renderStackIntoGUIWithColor)

[Tschipp]

7 hours ago, Cadiboo said:

http://lessie2d.tumblr.com/post/28673280483/opengl-blend-function-cheat-sheet-well-this-is

 

https://www.andersriggelsen.dk/glblendfunc.php

 

Have a look at those, but you’ll be doing a lot of work by trial & error in the debugger.

 

feel free to look at all my rendering code here

https://github.com/Cadiboo/WIPTech/blob/master/src/main/java/cadiboo/wiptech/client/render/tileentity/TESRAssemblyTable.java

(Hologram part)

 

https://github.com/Cadiboo/WIPTech/blob/master/src/main/java/cadiboo/wiptech/util/Utils.java

(renderStackWithColor and renderStackIntoGUIWithColor)

Thanks! 

Can your hologram properly render stained glass? I tried it with the blend function you used, but it didn't seem to work for me.

[Cadiboo]

4 hours ago, Tschipp said:

Thanks! 

Can your hologram properly render stained glass? I tried it with the blend function you used, but it didn't seem to work for me.

I’m not sure, I’ve only used it with solid models. Use the OpenGL cheat sheet and the blend testing page, also the way Minecraft renders water will 100% fuck up your rendering, not sure why but water doesn’t play nice with transparency/blending

Edited August 6, 2018 by Cadiboo