Text on top of 3D box

Processing Coding Questions
1

I have a 3D box and I would like to show data on top of the picture, which are always on front and are not moving, when I move the box.
I found, that hint can be used to disable depth test for that but that just gives text, which turns with the box camera angle, instead of staying independent of it.

2Dsurface2
2Dsurface2900×700 8.85 KB

I can try to rotate the text in opposition to the camera angle. That looks good, but as soon as I hit the mouse button to turn the box, the text slightly bends in.

2Dsurface
2Dsurface900×700 7.69 KB

I am not sure, how to get to a text, which just stay’s on on top of the rest without moving.

Here the relevant code of the part that draws everything :

void draw(){
  background(129,200,273);
  lights();
  translate(450,350,0);
  rotateY(camangle);
  noFill();
  stroke(0);
  box(boxsize);
  
 for (int j=0; j < coil.length; j++){
  for (int i = 1; i < coil[j].segments.length; i++){
    PVector point0 = new PVector();
    PVector point1 = new PVector();
    point0 = coil[j].segments[i-1].location.copy();
    point1= coil[j].segments[i].location.copy();
//check that segments are within box; while instead of if to cover cases with coordinates larger than boxsize/2    
   while (point0.x > boxsize/2){ point0.x -=boxsize; }
   while (point0.x < -boxsize/2){ point0.x +=boxsize; }
   while (point0.y > boxsize/2){ point0.y -=boxsize; }
   while (point0.y < -boxsize/2){ point0.y +=boxsize; }
   while (point0.z > boxsize/2){ point0.z -=boxsize; }
   while (point0.z < -boxsize/2){ point0.z +=boxsize; }
   while (point1.x > boxsize/2){ point1.x -=boxsize; }
   while (point1.x < -boxsize/2){ point1.x +=boxsize; }
   while (point1.y > boxsize/2){ point1.y -=boxsize; }
   while (point1.y < -boxsize/2){ point1.y +=boxsize; }
   while (point1.z > boxsize/2){ point1.z -=boxsize; }
   while (point1.z < -boxsize/2){ point1.z +=boxsize; } 
    
    //check if points are on opposite ends of box, then no line is drawn, 2*sdistance to accommodate deviation
    if (abs(point1.x - point0.x) < 2*sdistance && abs(point1.y - point0.y) < 2*sdistance && abs(point1.z - point0.z) < 2*sdistance*sdistance){
      strokeWeight(5);
      line(point0.x,point0.y, point0.z, point1.x, point1.y, point1.z);
      strokeWeight(1);
    }
  }
 }
  
  if(mousePressed == true){
    camangle += 0.1;
  }

   textSize(30);
   //hint(DISABLE_DEPTH_TEST);
   pushMatrix();
   rotateY(-camangle);
   text(coil[j].cRg, -boxsize+50+j*150, boxsize-200);
   popMatrix();
   //hint(ENABLE_DEPTH_TEST);
   
  }
}
2

If what you want is to draw like a 2d sketch over your 3d sketch, this post will help you:

3

That was, what I had looked at, but I didn’t reset the camera. Now it works. The ortho() function doesn’t help because it flattens the box, so to say.

4

The ortho() function at the end of draw must me paired with a call to perspective() at the beginning of draw to restore your desired camera mode. This should fix the flat box.

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