This moves all the byte swapping utilities into a header named Swap.h.
A dedicated header is much more preferable here due to the size of the
code itself. In general usage throughout the codebase, CommonFuncs.h was
generally only included for these functions anyway. These being in their
own header avoids dumping the lesser used utilities into scope. As well
as providing a localized area for more utilities related to byte
swapping in the future (should they be needed). This also makes it nicer
to identify which files depend on the byte swapping utilities in
particular.
Since this is a completely new header, moving the code uncovered a few
indirect includes, as well as making some other inclusions unnecessary.
The D3D backend was always forcing Anisotropic filtering when that is enabled regardless of how the game chose to configure the texture filtering registers; this causes the same issues as "Force Filtering" without Anisotropy, such as causing game UI elements to no longer line up adjacent correctly. Historically, OpenGL's Anisotropy support has always worked "better" than D3D's due to seeming to not have this problem; unfortunately, OpenGL's Anisotropy specification only gives GL_LINEAR based filtering modes defined behavior, with only the mipmap setting being required to be considered. Some OpenGL implementations were implicitly disabling Anisotropy when the min/mag filters were set to GL_NEAREST, but this behavior is not required by the spec so cannot be relied on.
Approximately three or four times now, the issue of pointers being
in an inconsistent state been an issue in the video backend renderers
with regards to tripping up other developers.
Global (ugh) resources are put into a unique_ptr and will always have a
well-defined state of being - null or not null
We are used to use the texture parameter for all util draw calls,
but AMD seems to have a bug where they use the sampler parameter
of stage 0 if no sampler is bound to the used stage.
So as workaround (and a bit as nicer code), we now use sampler
objects everywhere.
This drops the "feature" to load level 0 from the custom texture
and all other levels from the native one if the size matches.
But in my opinion, when a custom texture only provide one level,
no more should be used at all.
