http://bugs.winehq.org/show_bug.cgi?id=20307
--- Comment #14 from Henri Verbeet hverbeet@gmail.com 2009-12-01 04:52:43 --- Shadows usually imply some relation with depth/stencil buffer handling.
For what it's worth, it would make sense for 34dd27e3a8f9affb919db6f7c912040ded8eace8 to have some impact on performance, because it allows the depth blit in surface_load_ds_location() to happen even the color and depth buffers have different sizes. The impact should be minor though, certainly not as much as you're seeing. ec97383f6fb1a14c19dfcb85dd5239a8938c9e3c shouldn't change wined3d behaviour, just the GL entry points that are called.