private void BasicVis_RenderFrame(object sender, FrameEventArgs e)
{
OpenGLUtil.UseFrameBuffer(frameBufferID); // render to our custom framebuffer
GL.Viewport(0, 0, 1024, 1024); // render on teh entire framebuffer
GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit); // clear the screen
depthProgram.UseProgram(); // use the depth program
// camera properties
Matrix4 proj = Matrix4.CreateOrthographic(100, 100, 0, 100);
Matrix4 view = Matrix4.LookAt(new Vector3(4, 3, 3), Vector3.Zero, new Vector3(0, 1, 0));
Matrix4 model = Matrix4.Identity;
depthProgram.SetMVP(model * view * proj);
depthProgram.EnableAttributes();
depthProgram.LoadBuffer(vertexBufferID);
GL.DrawArrays(PrimitiveType.Triangles, 0, vertexBufferData.Length); // here the fragment shader will automatically write the depth to the texture bc of location 0
depthProgram.DisableAttributes();
OpenGLUtil.UseFrameBuffer(0); // now render to the screen
GL.Viewport(0, 0, Width, Height);
GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit); // clear the screen
textureProgram.UseProgram(); // use the texture program to display the 2d texture
textureProgram.SetTexture(textureID);
textureProgram.EnableAttributes();
textureProgram.LoadBuffer(vertexBufferID); // load the positions so that it can use them to map to the UV coordinates
GL.DrawArrays(PrimitiveType.Triangles, 0, vertexBufferData.Length);
textureProgram.DisableAttributes();
SwapBuffers();
}
private void RenderLightMapDepths()
{
foreach (var light in openGLLights)
{
Matrix4 depthProj = default(Matrix4);
Matrix4 depthView = default(Matrix4);
if (light.FrameBufferID == -1 || light.ShadowMapID == -1) // no dynamic shadows
{
depthProjs.Add(depthProj);
depthViews.Add(depthView);
continue;
}
if (light.IsDirectional)
{
// ortho view from light (directional)
var upDir = Vector3.UnitZ;
if (Vector3.Cross(upDir, light.Pos.Xyz).LengthSquared == 0)
{
upDir = Vector3.UnitY; // up can be any direction except the look at direction
}
depthProj = Matrix4.CreateOrthographic(FarClip, FarClip, -FarClip / 2, 2 * FarClip);
depthView = Matrix4.LookAt(FarClip * light.Pos.Xyz, Vector3.Zero, upDir);
}
else
{
// will look shitty for a point light
// projective view from light (spotlight)
var upDir = Vector3.UnitZ;
if (Vector3.Cross(upDir, light.ConeDir).LengthSquared == 0)
{
upDir = Vector3.UnitY; // up can be any direction except the look at direction
}
depthProj = Matrix4.CreatePerspectiveFieldOfView(light.ConeAngle * 2, 1.0f, Camera.MinRange, Camera.MaxRange); // uses camera specs to guide percision
depthView = Matrix4.LookAt(light.Pos.Xyz, light.Pos.Xyz + light.ConeDir, upDir);
}
OpenGLUtil.UseFrameBuffer(light.FrameBufferID); // use our custom framebuffer instead of the screen
GL.Viewport(0, 0, ShadowMapSize, ShadowMapSize); // render on teh entire framebuffer
GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit); // clear the framebuffer
depthProgram.UseProgram();
depthProgram.EnableAttributes();
depthProgram.LoadBuffer(vertexBufferID);
int startIndex = 0;
foreach (IGraphicalBody body in Bodies)
{
Matrix4 scale = Matrix4.Identity;
Matrix4 rotation = Matrix4.CreateFromQuaternion(body.Orientation.ToGLQuaternion());
Matrix4 translation = Matrix4.CreateTranslation(body.Translation.ToGLVector3());
Matrix4 model = scale * rotation * translation;
depthProgram.SetMVP(model * depthView * depthProj);
int numVerts = body.Triangles.Length * 3;
GL.DrawArrays(PrimitiveType.Triangles, startIndex, numVerts); // here the fragment shader will automatically write the depth to the texture bc of location 0
startIndex += numVerts;
}
depthProgram.DisableAttributes();
depthProjs.Add(depthProj);
depthViews.Add(depthView);
OpenGLUtil.CheckInvalidFrameBuffer();
}
}