Posted by sara on Sep 26, 2012; 11:26pm
URL: https://forum.jogamp.org/2D-Picking-with-Jogl-tp2594712p4026278.html

Hi,

unfortunately gluProject  did not solve my problem when I zoom in or zoom out the window,
So I wanna use picking code, but I do not know how to choose the values of glOrtho , I use the width and height but it did not work or other values did not work correctly ,this is my code?

  public void pick(GL gl) {
       
        int[] selectBuf = new int[BUFSIZE];
        IntBuffer selectBuffer = BufferUtil.newIntBuffer(BUFSIZE);
        int hits;
        int viewport[] = new int[4];

      gl.glGetIntegerv(GL.GL_VIEWPORT, viewport, 0);
       gl.glSelectBuffer(BUFSIZE, selectBuffer);
      gl.glRenderMode(GL.GL_SELECT);

        gl.glInitNames();
       gl.glPushName(-1);            
       gl.glPushMatrix();
       gl.glLoadIdentity();
       glu.gluPickMatrix((double) pickPoint.x,
              (double) ( viewport[3] -pickPoint.y),
                5.0, 5.0, viewport, 0);
         
       gl.glOrtho(0.0, wid, 0.0,hi, -0.5, 2.5);        
        drawRects(gl, GL.GL_SELECT);
       gl.glPopMatrix();
       gl.glFlush();

       hits = gl.glRenderMode(GL.GL_RENDER);
      selectBuffer.get(selectBuf);
      processHits(hits, selectBuf);

    }

I have to present this program in Friday, I really do not know how to solve?

Thanks in advance,
Sara