Flip Y-Axis

[Videogamers0]

I would use Matrix.CreateOrthographicOffCenter like shown here:

Inverting Y Axis

@JasonBricco Use a orthographic projection matrix like this to get y=0 at the bottom. Note that this example also does adds an offset of half a pixel to properly account for sampling texels. You may wish to change the far and near plane to whatever. var viewport = GraphicsDevice.Viewport; var projectionMatrix = Matrix.CreateTranslation(-0.5f, -0.5f, 0) * Matrix.CreateOrthographicOffCenter(0, viewport.Width, 0, viewport.Height, 0, 1); See https://msdn.microsoft.com/en-us/library/bb195659.aspx …

Also I wouldn’t recommend manually setting the components of the transform. Instead create it using matrix multiplications such as…

TransformMatrix = 
      Matrix.CreateOrthographicOffCenter(...) * 
      Matrix.CreateScale(_zoom, _zoom, 1) * 
      Matrix.CreateTranslation(new Vector3(-CameraPosition, 0f))

etc, as it tends to be much more maintainable and extensible code