protected override void OnLoad()
{
base.OnLoad();
// initialize shader (load sources, create/compile/link shader program, error checking)
// when using the factory method the shader sources are retrieved from the ShaderSourceAttributes
_program = ProgramFactory.Create <SimpleColorProgram>();
// this program will be used all the time so just activate it once and for all
_program.Use();
//arbitrary black box to load mesh data
string jsonString = File.ReadAllText("./Data/Meshes/OpenTK.fakeformat");
MeshData meshData = JsonSerializer.Deserialize <MeshData>(jsonString);
Buffer <uint> IndexBuffer = new Buffer <uint>();
IndexBuffer.Init(BufferTarget.ElementArrayBuffer, meshData.Indices.Select(index => index - 1).ToArray());
Buffer <Vector3> VertBuffer = new Buffer <Vector3>();
VertBuffer.Init(BufferTarget.ArrayBuffer, Enumerable.Range(0, meshData.Vertices.Count / 3).Select(a => new Vector3(meshData.Vertices[a * 3], meshData.Vertices[a * 3 + 1], meshData.Vertices[a * 3 + 2])).ToArray());
//a bit of a hack, i wanted the mesh to have some visual depth.
//the only reason this works is I just happen to know the Z coordinate for the mesh is in a certain range
//other meshes will either look stupid or just throw exceptions because the color values are out of range
Buffer <uint> ColorBuffer = new Buffer <uint>();
ColorBuffer.Init(BufferTarget.ArrayBuffer, VertBuffer.Content.Select(vertex => (uint)Color.FromArgb((int)(vertex.Z * 500) + 100, (int)(vertex.Z * 500) + 100, (int)(vertex.Z * 500) + 100).ToArgb()).ToArray());
mesh = new DynamicShape()
.WithVertexAttrib(_program.InPosition, VertBuffer)
.WithVertexAttrib(_program.InColor, ColorBuffer)
.WithElementBuffer(IndexBuffer)
.WithDisposeFunction(() => {
VertBuffer?.Dispose();
IndexBuffer?.Dispose();
ColorBuffer?.Dispose();
})
.SetDrawFunction((VAO) => {
VAO.DrawElements(PrimitiveType.Triangles, IndexBuffer.ElementCount);
});
// set camera position
ActiveCamera.Position = new Vector3(0, 0, 3);
// set a nice clear color
GL.ClearColor(Color.MidnightBlue);
GL.Enable(EnableCap.DepthTest);
GL.Enable(EnableCap.CullFace);
GL.CullFace(CullFaceMode.Back);
}
protected override void OnRenderFrame(FrameEventArgs e)
{
base.OnRenderFrame(e);
// set up render to texture
_framebuffer.Bind(FramebufferTarget.Framebuffer);
GL.Viewport(0, 0, FramebufferWidth, FramebufferHeight);
GL.ClearColor(Color.Black);
GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);
// render rotating cube to texture
_colorProgram.Use();
_colorProgram.ModelViewProjectionMatrix.Set(
Matrix4.CreateRotationX((float)FrameTimer.TimeRunning / 1000)
* Matrix4.CreateRotationY((float)FrameTimer.TimeRunning / 1000)
* Matrix4.CreateTranslation(0, 0, -5)
* Matrix4.CreatePerspectiveFieldOfView(MathHelper.PiOver4, FramebufferWidth / (float)FramebufferHeight, 0.1f, 100));
_cube.Draw();
// reset to default framebuffer
Framebuffer.Unbind(FramebufferTarget.Framebuffer);
// set up viewport for the window
GL.Viewport(0, 0, Size.X, Size.Y);
GL.ClearColor(Color.MidnightBlue);
GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);
// render quad with texture
_textureProgram.Use();
_textureProgram.ModelViewProjectionMatrix.Set(ActiveCamera.ViewProjectionMatrix);
_quad.Draw();
// swap buffers
SwapBuffers();
}
private void OnRenderFrame(object sender, FrameEventArgs e)
{
// set up render to texture
_framebuffer.Bind(FramebufferTarget.Framebuffer);
GL.Viewport(0, 0, FramebufferWidth, FramebufferHeight);
GL.ClearColor(Color.Black);
GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);
// render rotating cube to texture
_colorProgram.Use();
_colorProgram.ModelViewProjectionMatrix.Set(
Matrix4.CreateRotationX((float)FrameTimer.TimeRunning / 1000)
* Matrix4.CreateRotationY((float)FrameTimer.TimeRunning / 1000)
* Matrix4.CreateTranslation(0, 0, -5)
* Matrix4.CreatePerspectiveFieldOfView(MathHelper.PiOver4, FramebufferWidth / (float)FramebufferHeight, 0.1f, 100));
_cubeVao.Bind();
_cubeVao.DrawElements(PrimitiveType.Triangles, _cube.IndexBuffer.ElementCount);
// reset to default framebuffer
Framebuffer.Unbind(FramebufferTarget.Framebuffer);
// set up viewport for the window
GL.Viewport(0, 0, Width, Height);
GL.ClearColor(Color.MidnightBlue);
GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);
SetupPerspective();
// render quad with texture
_textureProgram.Use();
_textureProgram.ModelViewProjectionMatrix.Set(ModelView * Projection);
_quadVao.Bind();
_quadVao.DrawArrays(PrimitiveType.TriangleStrip, 0, _quad.VertexBuffer.ElementCount);
// swap buffers
SwapBuffers();
}