private Vector3 screenToWorld(Vector3 coord, Matrix view, Matrix proj, Matrix world, ViewportF screen)
{
Vector3 near = screen.Unproject(new Vector3(coord.X * screen.Width, coord.Y * screen.Height, 0.0f), proj, view, world);
Vector3 far = screen.Unproject(new Vector3(coord.X * screen.Width, coord.Y * screen.Height, 1.0f), proj, view, world);
return(near + (far - near) * 0.1f);
}
public Ray ScreenPointToRay(Vector2 screenCoords)
{
// expand coord to fit the view
screenCoords.X *= _graphicsDevice.BackBuffer.Width;
screenCoords.Y *= _graphicsDevice.BackBuffer.Height;
// translate vectors into world space by unprojecting them.
var customViewport = new ViewportF(0, 0, _graphicsDevice.BackBuffer.Width, _graphicsDevice.BackBuffer.Height, _nearZClip, _farZClip);
var nearWorldCoord = customViewport.Unproject(new Vector3(screenCoords, _nearZClip), ProjectionMatrix, ViewMatrix, Matrix.Identity);
var farWorldCoord = customViewport.Unproject(new Vector3(screenCoords, _farZClip), ProjectionMatrix, ViewMatrix, Matrix.Identity);
var dir = (farWorldCoord - nearWorldCoord).ToNormal();
return(new Ray(nearWorldCoord, dir));
}
public Vector3 UnprojectScreenCoord(Vector3 screenCoords)
{
// expand coord to fit the view
screenCoords.X *= _graphicsDevice.BackBuffer.Width;
screenCoords.Y *= _graphicsDevice.BackBuffer.Height;
// translate vectors into world space by unprojecting them.
var customViewport = new ViewportF(0, 0, _graphicsDevice.BackBuffer.Width, _graphicsDevice.BackBuffer.Height, _nearZClip, _farZClip);
var worldCoord = customViewport.Unproject(screenCoords, ProjectionMatrix, ViewMatrix, Matrix.Identity);
return(worldCoord);
}