.

Edited January 23, 20232 yr by D0XY

The GUI class, it seems, only has methods for drawing horizontal/vertical lines, so I don't think there's a convenient pre-written utility method accessible here. However, you can still accomplish this through the Tessellator.

 

--Aquire an instance of the Tessellator with Tessellator#getInstance(), and an instance of BufferBuilder by calling Tessellator#getBuffer() on your Tessellator object.

--Set the desired settings with GlStateManager#whatever().

--Call BufferBuilder#begin(), passing in the desired line mode as one of the public static final ints in the GL11 class, and the desired vertex format from the DefaultVertexFormats class.

--Add the two vertices of your line with BufferBuilder#pos(), BufferBuilder#color(), etc, and end each vertex with BufferBuilder#endVertex().

(A pseudo example below, since that was unclear)

buffer.pos().color().endVertex();
buffer.pos().color().endVertex();

--With everything above set up, call Tessellator#draw() on your Tessellator object.

--Reset the GlStateManager settings to what they were before.

 

EDIT: You should also call GlStateManager#pushMatrix() before BufferBuilder#begin(), and GlStateManager#popMatrix() after Tessellator#draw(). This shifts the current matrix out from being worked on, to make space for your own, and then back in place once you're done with it (At least I think so, right?).

Edited October 19, 20196 yr by SerpentDagger

.

Edited January 23, 20232 yr by D0XY

6 minutes ago, D0XY said:

GL11.glPushMatrix();

Do not interact with OpenGL directly like that. Don't use GL11 use GLStateManager. Also please use the Tesselator.