SharpGL WPF draw from code behind not using OpenGLDraw

Question

I'm trying to draw on a OpenGLControl from the code behind (or preferably using the MVVM pattern) without using the OpenGLDraw eventhandler. The reason for this is that I'm using it for augmented reality and the camera is using an external trigger, so I want to draw whenever a new frame comes in from the camera. In the example I've used a timer to simulate the camera.

I've tried the following:

<Window x:Class="Example1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Test" Height="400" Width="600"
        xmlns:sharpGL="clr-namespace:SharpGL.WPF;assembly=SharpGL.WPF">
    <Grid>
        <sharpGL:OpenGLControl
            x:Name="glControl"          
            OpenGLInitialized="OpenGLControl_OpenGLInitialized"
            RenderContextType="DIBSection"
            DrawFPS="True"/>
    </Grid>
</Window>

And the code behind:

using System.Windows;
using SharpGL;
using SharpGL.SceneGraph;
using System.Timers;

namespace Example1
{
    public partial class MainWindow : Window
    {
        Timer clock = new Timer(1000f / 60f);
        float rotatePyramid = 0;

        public MainWindow()
        {
            InitializeComponent();
        }
        private void OpenGLControl_OpenGLInitialized(object sender, OpenGLEventArgs args)
        {
            OpenGL gl = args.OpenGL;
            gl.Enable(OpenGL.GL_DEPTH_TEST);

            clock.Elapsed += OnFrame;
            clock.Start();
        }

        private void OnFrame(object sender, ElapsedEventArgs e)
        {

            OpenGL gl = glControl.OpenGL;

            //  Clear the color and depth buffers.
            gl.Clear(OpenGL.GL_COLOR_BUFFER_BIT | OpenGL.GL_DEPTH_BUFFER_BIT);

            //  Reset the modelview matrix.
            gl.LoadIdentity();

            //  Move the geometry into a fairly central position.
            gl.Translate(0f, 0.0f, -6.0f);

            //  Draw a pyramid. First, rotate the modelview matrix.
            gl.Rotate(rotatePyramid, 0.0f, 1.0f, 0.0f);

            //  Start drawing triangles.
            gl.Begin(OpenGL.GL_TRIANGLES);

            gl.Color(1.0f, 0.0f, 0.0f);
            gl.Vertex(0.0f, 1.0f, 0.0f);
            gl.Color(0.0f, 1.0f, 0.0f);
            gl.Vertex(-1.0f, -1.0f, 1.0f);
            gl.Color(0.0f, 0.0f, 1.0f);
            gl.Vertex(1.0f, -1.0f, 1.0f);

            gl.Color(1.0f, 0.0f, 0.0f);
            gl.Vertex(0.0f, 1.0f, 0.0f);
            gl.Color(0.0f, 0.0f, 1.0f);
            gl.Vertex(1.0f, -1.0f, 1.0f);
            gl.Color(0.0f, 1.0f, 0.0f);
            gl.Vertex(1.0f, -1.0f, -1.0f);

            gl.Color(1.0f, 0.0f, 0.0f);
            gl.Vertex(0.0f, 1.0f, 0.0f);
            gl.Color(0.0f, 1.0f, 0.0f);
            gl.Vertex(1.0f, -1.0f, -1.0f);
            gl.Color(0.0f, 0.0f, 1.0f);
            gl.Vertex(-1.0f, -1.0f, -1.0f);

            gl.Color(1.0f, 0.0f, 0.0f);
            gl.Vertex(0.0f, 1.0f, 0.0f);
            gl.Color(0.0f, 0.0f, 1.0f);
            gl.Vertex(-1.0f, -1.0f, -1.0f);
            gl.Color(0.0f, 1.0f, 0.0f);
            gl.Vertex(-1.0f, -1.0f, 1.0f);

            gl.End();
            gl.Flush();

            rotatePyramid += 3.0f;
        }
    }
}

This only renders a black screen with the FPS counter in it. I think it has to do with not getting the right OpenGL object. I would really like to use the MVVM pattern and using bindings, but if that's not possible then code behind would also work, as long is I can draw whenever I get a frame from the camera.

SharpGL WPF draw from code behind not using OpenGLDraw

0 Answers0