LWJGL make object always face up

Question

I need to make 3D objects to face up same way no matter their position to the camera. As if camera was very very far away and zoomed in. Here is what I mean (take a look at the pillar and walls): http://youtu.be/Pn9fh93oV-c

Here is what I have so far:

package pack;

import org.lwjgl.LWJGLException;
import org.lwjgl.input.Keyboard;
import org.lwjgl.opengl.Display;
import org.lwjgl.opengl.DisplayMode;
import org.lwjgl.opengl.GL11;

import java.util.Random;

import static org.lwjgl.opengl.GL11.*;
import static org.lwjgl.util.glu.GLU.gluPerspective;

public class Main {

float viewx, viewy;
float angle;

public static void main(String[] args) {
    Main main = new Main();
    main.start();
}

private void start() {
    try {
        Display.setDisplayMode(new DisplayMode(640, 480));
        Display.setTitle("Three Dee Demo");
        Display.create();
    } catch (LWJGLException e) {
        e.printStackTrace();
        Display.destroy();
        System.exit(1);
    }
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluPerspective((float) 30, 640f / 480f, 0.001f, 100);
    glMatrixMode(GL_MODELVIEW);
    glEnable(GL_DEPTH_TEST);
    glTranslatef(0, 0, -20);

    while (!Display.isCloseRequested()) {
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

        update();
        render();

        Display.update();
        Display.sync(60);
    }

    Display.destroy();
    System.exit(0);
}

private void render() {

     GL11.glBegin(GL11.GL_QUADS);    
     GL11.glColor3f(1.0f,1.0f,0.0f);           
     GL11.glVertex3f( 1.0f, 1.0f,-1.0f);        
     GL11.glVertex3f(-1.0f, 1.0f,-1.0f);        
     GL11.glVertex3f(-1.0f, 1.0f, 1.0f);
     GL11.glVertex3f( 1.0f, 1.0f, 1.0f);  
     GL11.glColor3f(1.0f,0.5f,0.0f);            
     GL11.glVertex3f( 1.0f,-1.0f, 1.0f);
     GL11.glVertex3f(-1.0f,-1.0f, 1.0f);
     GL11.glVertex3f(-1.0f,-1.0f,-1.0f);
     GL11.glVertex3f( 1.0f,-1.0f,-1.0f);
     GL11.glColor3f(1.0f,0.0f,0.0f);
     GL11.glVertex3f( 1.0f, 1.0f, 1.0f);
     GL11.glVertex3f(-1.0f, 1.0f, 1.0f);
     GL11.glVertex3f(-1.0f,-1.0f, 1.0f);
     GL11.glVertex3f( 1.0f,-1.0f, 1.0f);
     GL11.glColor3f(1.0f,1.0f,0.0f);
     GL11.glVertex3f( 1.0f,-1.0f,-1.0f);
     GL11.glVertex3f(-1.0f,-1.0f,-1.0f);
     GL11.glVertex3f(-1.0f, 1.0f,-1.0f);
     GL11.glVertex3f( 1.0f, 1.0f,-1.0f);
     GL11.glColor3f(0.0f,0.0f,1.0f);
     GL11.glVertex3f(-1.0f, 1.0f, 1.0f);
     GL11.glVertex3f(-1.0f, 1.0f,-1.0f);
     GL11.glVertex3f(-1.0f,-1.0f,-1.0f);
     GL11.glVertex3f(-1.0f,-1.0f, 1.0f);
     GL11.glColor3f(1.0f,0.0f,1.0f);
     GL11.glVertex3f( 1.0f, 1.0f,-1.0f);
     GL11.glVertex3f( 1.0f, 1.0f, 1.0f);
     GL11.glVertex3f( 1.0f,-1.0f, 1.0f);
     GL11.glVertex3f( 1.0f,-1.0f,-1.0f);
 GL11.glEnd();    

}

private void update() {
    if (Keyboard.isKeyDown(Keyboard.KEY_UP)) {
        viewx -= 0.1f*(float)Math.sin(Math.toRadians(angle));
        viewy -= 0.1f*(float)Math.cos(Math.toRadians(angle));
    }

    if (Keyboard.isKeyDown(Keyboard.KEY_DOWN)) {
        viewx += 0.1f*(float)Math.sin(Math.toRadians(angle));
        viewy += 0.1f*(float)Math.cos(Math.toRadians(angle));
    }
    if (Keyboard.isKeyDown(Keyboard.KEY_RIGHT)) {
        viewx+= 0.1f*(float)Math.sin(Math.toRadians(angle-90));
        viewy+=0.1f*(float)Math.cos(Math.toRadians(angle-90));
    }

    if (Keyboard.isKeyDown(Keyboard.KEY_LEFT)) {
        viewx+= 0.1f*(float)Math.sin(Math.toRadians(angle+90));
        viewy+=0.1f*(float)Math.cos(Math.toRadians(angle+90));
    }

    if (Keyboard.isKeyDown(Keyboard.KEY_Q)) {
         angle += 1;
    }


    if (Keyboard.isKeyDown(Keyboard.KEY_E)) {
        angle -= 1;
    }

    glLoadIdentity();
    glRotatef (angle, 0, 0, 1);
    glTranslated(viewx, viewy, -20);

    GL11.glBegin(GL11.GL_QUADS);    
    GL11.glColor3f(1.0f,1.0f,0.0f);           
    GL11.glVertex3f( -viewx-0.2f, -viewy-0.2f,0);        
    GL11.glVertex3f(-viewx+0.2f, -viewy-0.2f, 0);        
    GL11.glVertex3f(-viewx+0.2f, -viewy+0.2f, 0);
    GL11.glVertex3f( -viewx-0.2f, -viewy+0.2f, 0);  
    glEnd();       

}
}

Answer 1

That game appeaers to be using an orthographic projection - notice how the thing farther away from the camera are not smaller. That is why the direction of lines doesn't depend on the camera position.

The left half of this picture shows a grid of crates rendered with a perspective projection. The right half shows the same grid rendered with an orthographic projection.

Notice how, with the orthographic projection, all of the crates look identical regardless of their position, and regardless of their distance from the camera - only their orientation matters.

In the OpenGL fixed-function pipeline, you can set up an orthographic projection using glOrtho. If you are using the programmable pipeline, then it depends on your specific program; in general, you'll want to use a projection matrix in the fo