I know this should probably go to stack overflow, but:

 

When rendering with vertexes (we are talking 2D), you can pretty much draw anything you want - rect, circle, arc or like in my case - rect with arc corners.

 

Now - coloring that shit is also simple, but what about applying repeating texture onto non-rectangular vertexes?

 

 

Basically - what's the approach on drawing box above?

Rules:

* Background = repeating any texture.

* Arc-corners = of any radius.

* Outside of bounds (white border) will not be rendered (not included in image)

 

EDIT

 

Okay - I think using stencils is right way, but  - any good tutorials on that?

After trying everything... does MC support stencil buffers? I think Forge did something in about 1.6.4 (or earlier) that was enabling stencil buffer, but idk if its still a thing - can't find anything. Do I have to do it myself?

 

EDIT

 

Everything points to "It doesn't".

 

So question:

 

How to create/enable stencil buffer without ASM (Minecraft#createDisplay())?

 

Pre-init:

Minecraft.getMinecraft().getFramebuffer().enableStencil();

Call:

System.out.println(GL11.glGetInteger(GL11.GL_STENCIL_BITS));
System.out.println(Minecraft.getMinecraft().getFramebuffer().isStencilEnabled());

Out:

8
true

 

P.S: Now that last part of comic... how to do rest

Of course this only works if the user has FBOs enabled.

 

Question then - how big is the part of users that doesn't or could have some problems there? I am not gonna spend weeks on this design if it turns out that it doesn't work for 50% of ppl.

 

...if you would have to guess.

 

EDIT: Wait... I think this is retarded question. Like... really retarded.

You know the day is good when you beat one of design problems.

 

GL11.glEnable(GL11.GL_STENCIL_TEST); // Turn on da test
GL11.glClear(GL11.GL_STENCIL_BUFFER_BIT); // Flush old data

GL11.glStencilMask(0xFF); // Writing = ON
GL11.glStencilFunc(GL11.GL_ALWAYS, 1, 0xFF); // Always "add" to frame
GL11.glStencilOp(GL11.GL_KEEP, GL11.GL_KEEP, GL11.GL_REPLACE); // Replace on success
//Anything rendered here becomes "cut" frame.

GL11.glStencilMask(0x00); // Writing = OFF
GL11.glStencilFunc(GL11.GL_NOTEQUAL, 0, 0xFF); // Anything that wasn't defined above will not be rendered.
//Anything rendered here will be cut if goes beyond frame defined before.

GL11.glDisable(GL11.GL_STENCIL_TEST); // Turn this shit off!

 

EDIT: Edited code to more universal.