I am trying to render a very simple tree by using a tree texture with transparency and rendering it along the x and y axis. But if I render something else behind it after, it doesn't work.

This is because of the way the z-buffer works, and in C++ I could do glDepthMask(GL_FALSE), render the two QUADS, and then call glDepthMask(GL_TRUE).

I tried doing this in Processing like this-
Code:

PGraphicsOpenGL pgl = (PGraphicsOpenGL) g;
    GL gl = pgl.beginGL();
    gl.glDepthMask(false);
    pushMatrix();
    translate( loc.x, loc.y, loc.z );

     beginShape( QUADS );
     texture( tree );
     vertex( 0, -30, 0, 0, 1 );
     vertex( 0, 30, 0, 1, 1 );
     vertex( 0, 30, 60, 1, 0 );
     vertex( 0, -30, 60, 0, 0 );
     
     vertex( -30, 0, 0, 0, 1 );
     vertex( 30, 0, 0, 1, 1 );
     vertex( 30, 0, 60, 1, 0 );
     vertex( -30, 0, 60, 0, 0 );
     endShape();
     
     popMatrix();
     gl.glDepthMask(true);
     pgl.endGL(); 

But the trees don't appear. If i remove pgl.endGL(), the trees appear fine, but I get a whole slew of other errors.

Am I allowed to call processing GL statements within beginGL(), and if so, why aren't my trees appearing?

Thanks!