Question

I made some code to produce boxes every time my code encounters a white pixel in my level image. However, it doesn’t seem to work. It only works if I comment out the actual loading from image parts.

        GL11.glMatrixMode(GL11.GL_PROJECTION);
    GL11.glLoadIdentity();
    GL11.glOrtho(-5, 5, -5, 5, -20, 20);
    GL11.glMatrixMode(GL11.GL_MODELVIEW);
    float camPosX=0, camPosY=0;
    for(int i=0;i<level.getWidth();i++){
        for(int j=0;j<level.getHeight();j++){
            if(level.getRGB(i, j)==Color.red.getRGB()){camPosX=i;camPosY=j;}
        }
    }
    System.out.println("Camera position is "+camPosX+", "+camPosY);
    int x=0;
    while (!Display.isCloseRequested()) {
        Display.sync(60);
        //poll for keypresses first, default key is 'forward'
        if(Keyboard.isKeyDown(Keyboard.KEY_NUMPAD8));



        GL11.glClear(GL11.GL_DEPTH_BUFFER_BIT|GL11.GL_COLOR_BUFFER_BIT);
        //GL11.glEnable(GL11.GL_CULL_FACE);
        GL11.glEnable(GL11.GL_DEPTH_TEST);
        GL11.glColor3f(0, 0, 0);
        for(int i=0;i<level.getWidth();i++){
            for(int j=0;j<level.getHeight();j++){
                if(level.getRGB(i, j)==Color.WHITE.getRGB()){
                    GL11.glTranslatef(-i, 0, -j);
                    GL11.glRotatef(45, 1, 1, 1);
                    GL11.glBegin(GL11.GL_QUADS);
                    GL11.glColor3f(1.0f,0.0f,0.0f);          // Set The Color To Red
                    GL11.glVertex3f( 0.5f, 0.5f, 0.5f);          // Top Right Of The Quad (Front)
                    GL11.glVertex3f(-0.5f, 0.5f, 0.5f);          // Top Left Of The Quad (Front)
                    GL11.glVertex3f(-0.5f,-0.5f, 0.5f);          // Bottom Left Of The Quad (Front)
                    GL11.glVertex3f( 0.5f,-0.5f, 0.5f);          // Bottom Right Of The Quad (Front)
                    GL11.glVertex3f( 0.5f,-0.5f,-0.5f);          // Bottom Left Of The Quad (Back)
                    GL11.glVertex3f(-0.5f,-0.5f,-0.5f);          // Bottom Right Of The Quad (Back)
                    GL11.glVertex3f(-0.5f, 0.5f,-0.5f);          // Top Right Of The Quad (Back)
                    GL11.glVertex3f( 0.5f, 0.5f,-0.5f);          // Top Left Of The Quad (Back)
                    GL11.glVertex3f(-0.5f, 0.5f, 0.5f);          // Top Right Of The Quad (Left)
                    GL11.glVertex3f(-0.5f, 0.5f,-0.5f);          // Top Left Of The Quad (Left)
                    GL11.glVertex3f(-0.5f,-0.5f,-0.5f);          // Bottom Left Of The Quad (Left)
                    GL11.glVertex3f(-0.5f,-0.5f, 0.5f);          // Bottom Right Of The Quad (Left)
                    GL11.glVertex3f( 0.5f, 0.5f,-0.5f);          // Top Right Of The Quad (Right)
                    GL11.glVertex3f( 0.5f, 0.5f, 0.5f);          // Top Left Of The Quad (Right)
                    GL11.glVertex3f( 0.5f,-0.5f, 0.5f);          // Bottom Left Of The Quad (Right)
                    GL11.glVertex3f( 0.5f,-0.5f,-0.5f);          // Bottom Right Of The Quad (Right)
                    GL11.glEnd();
                    GL11.glLoadIdentity();
                }
            }
        }
        GL11.glTranslatef(-camPosX, 0, -camPosY);
        Display.update();
    }

Answer 1

In the main loop where you generate the boxes, you probably want to do

...
if(level.GetRGB(i, j)==Color.WHITE.getRGB()) {
    GL11.glPushMatrix(); // store current matrix
    GL11.glTranslatef(-i, 0, -j);
    ...
    GL11.glPopMatrix(); // instead of GL11.glLoadIdentity()
}

The line

GL11.glTranslatef(-camPosX, 0, -camPosY);

probably does not what you think it does. It does not have any effect on the following call Display.update(). However, it will affect the next run of your main loop, because you do not call GL11.glLoadIdentity() at the beginning of the main loop. I suggest moving it to the beginning of the main loop and calling glLoadIdentity() before.