Posted by Daniel S. on Mar 22, 2011; 2:44pm
URL: https://forum.jogamp.org/Issue-about-textures-and-glOrtho-tp2675799p2715127.html

Hi,

thanks for your hints (statemachine ;-). I'm still not so firm with OpenGL.
 I've tried gl.glDisable(GL.GL_DEPTH_TEST) and gl.glDisable(GL.GL_CULL_FACE); but nothing changed.

So I have search a lot in the internet and coded a new example. Now textures and glOrtho work fine. but I can't draw anythiong on my background image. I'm guessing that I have to load the Modelview matrix after drawing the quad with the texture. But I can't get it runnig....

Maybe you know the right instructions :-)

Here is my display Method:


public void display(GLAutoDrawable drawable) {
                // TODO Auto-generated method stub
                final GL gl = drawable.getGL();

                // Clear screen.
                gl.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT);
               
               
               
               
               
               
               
        gl.glMatrixMode(GL.GL_PROJECTION);  // Select Projection
        gl.glPushMatrix();      // Push The Matrix
        gl.glLoadIdentity();      // Reset The Matrix
        gl.glOrtho(0, 640, 480, 0, -1, 1);  // Select Ortho Mode (640x480)
        gl.glMatrixMode(GL.GL_MODELVIEW);  // Select Modelview Matrix
        gl.glPushMatrix();      // Push The Matrix
        gl.glLoadIdentity();      // Reset The Matrix

                  // Enable two-dimensional texturing.
                 
                  tex.enable ();
                 
                 
        // Bind this texture to the current rendering context.
                 
        tex.bind ();
                 
        gl.glBegin(GL.GL_QUADS);
                 
        gl.glTexCoord2f(0, 1); // Texture Coordinate  ( 0, 1 )
        gl.glVertex2f(0, 0);  // First Vertex    (   0,   0 )

          // Texture Coordinate  ( 0, 0 )
          gl.glTexCoord2f(0, 0 );
          gl.glVertex2f(0, 480);  // Second Vertex  (   0, 480 )

          // Texture Coordinate  ( 1, 0 )
          gl.glTexCoord2f(1 , 0 );  
          gl.glVertex2f(640, 480);  // Third Vertex    ( 640, 480 )

          // Texture Coordinate  ( 1, 1 )
          gl.glTexCoord2f(1 , 1 );  
          gl.glVertex2f(640, 0);  // Fourth Vertex  ( 640,   0 )
                 
  gl.glEnd();
  tex.disable ();
                 
       
        // this trinagle isn't shown
                  gl.glBegin(GL.GL_TRIANGLES);
                        gl.glColor3f(1,0,0);
                        gl.glVertex2d(100,100);
                        gl.glVertex2d(150,150);
                        gl.glVertex2d(300,300);
                  gl.glEnd();
                 
                 
        }


Thanks in advance!

Greetings,
Daniel