- (void)startRenderLoop:(GLView *)MeshGLView
{
    if(displayLink == nil)
    {
        displayLink = [self.view.window.screen displayLinkWithTarget:MeshGLView selector:@selector(drawView)];
        [displayLink addToRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
        NSLog(@"Starting Render Loop");
    }
}


- (void)drawView:(GLView *)theView {
    NSLog(@"drawView");
    if (theView.context != nil)
    {
        [EAGLContext setCurrentContext:theView.context];

        if (![theView getFrameBuffer])
            [theView createFramebuffer];
    }

    if (redraw) {
        NSLog(@"drawMesh");
        [self drawMesh:theView];
        redraw = NO;
    }
}

- (void)drawMesh:(GLView *)MeshView {

    if (MeshView.context != nil)
    {
        //make it the current context for rendering
        [EAGLContext setCurrentContext:MeshView.context];

        //if our framebuffers have not been created yet, do that now!
        if (![MeshView getFrameBuffer])
            [MeshView createFramebuffer];
    }

    glMatrixMode(GL_MODELVIEW);

    Mesh mesh = _sculpture->getMesh();
    int numberOfTriangles = mesh.getNumberOfTriangles();
    std::vector<float> vertices = mesh.getVertices();
    std::vector<float> normals = mesh.getNormals();

    //Draw mesh
    {
    glColor4f(1,0,1,1);

    glEnable(GL_COLOR_MATERIAL);
    glShadeModel(GL_FLAT);

    glEnableClientState(GL_VERTEX_ARRAY);
    glEnableClientState(GL_NORMAL_ARRAY);

        static double theta = 0;
        theta += 0.03;
        glRotatef(theta, 1, 1, 0);

    glVertexPointer(3, GL_FLOAT, 0, vertices.data());
    glNormalPointer(GL_FLOAT, 0, normals.data());

    glDrawArrays(GL_TRIANGLES, 0, numberOfTriangles);


    glDisableClientState(GL_NORMAL_ARRAY);
    glDisableClientState(GL_VERTEX_ARRAY);


    glShadeModel(GL_SMOOTH);
    glDisable(GL_COLOR_MATERIAL);
    glColor4f(1, 1, 1, 1);
    }

    //Draw Axes
    {
        const GLfloat lineX[] = {
            FrustumData.left * FrustumData.ratio, (FrustumData.top + FrustumData.bottom) / 2 * FrustumData.ratio, -FrustumData.zFar, //point A
            FrustumData.right * FrustumData.ratio, (FrustumData.top + FrustumData.bottom) / 2 * FrustumData.ratio, -FrustumData.zFar //point B
        };
        const GLfloat lineY[] = {
            (FrustumData.left + FrustumData.right) / 2 * FrustumData.ratio , FrustumData.bottom * FrustumData.ratio, -FrustumData.zFar, //point A
            (FrustumData.left + FrustumData.right) / 2 * FrustumData.ratio , FrustumData.top * FrustumData.ratio, -FrustumData.zFar //point B
        };
        const GLfloat lineZ[] = {
            (FrustumData.left + FrustumData.right) / 2 * FrustumData.ratio, (FrustumData.top + FrustumData.bottom) / 2 * FrustumData.ratio, -FrustumData.zFar, //point A
            (FrustumData.left + FrustumData.right) / 2 * FrustumData.ratio, (FrustumData.top + FrustumData.bottom) / 2 * FrustumData.ratio, -FrustumData.zNear //point B
        };

        glEnableClientState(GL_VERTEX_ARRAY);

        glColor4f(1.0f, 0.0f, 0.0f, 1.0f); // opaque red
        glVertexPointer(3, GL_FLOAT, 0, lineX);
        glDrawArrays(GL_LINES, 0, 2);

        glColor4f(0.0f, 1.0f, 0.0f, 1.0f); // opaque green
        glVertexPointer(3, GL_FLOAT, 0, lineY);
        glDrawArrays(GL_LINES, 0, 2);

        glColor4f(0.0f, 0.0f, 1.0f, 1.0f); // opaque blue
        glVertexPointer(3, GL_FLOAT, 0, lineZ);
        glDrawArrays(GL_LINES, 0, 2);

        glDisableClientState(GL_VERTEX_ARRAY);
    }
}