SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.
Now that we've extracted all of the stateless functions that can be
hidden, it's time to make the index generator a regular class with
active data members.
This can just be a member that sits within the vertex manager base
class. By deglobalizing the state of the index generator we also get rid
of the wonky dual-initializing that was going on within the OpenGL
backend.
Since the renderer is always initialized before the vertex manager, we
now only call Init() once throughout the execution lifecycle.
We can use if constexpr with the template functions that pass in a
non-type template parameter, allowing the removal of branches that
aren't taken at compile time.
Compilers will generally do this by default, however, we now give a
gentle prodding to the compiler if this would otherwise not be the case.
These don't rely on any of the static members within the IndexGenerator
class, so we can make all of these functions fully internal to the
translation unit.
This is much better as prefixed double underscores are reserved for the
implementation when it comes to identifiers. Another reason its better,
is that, on Windows, where __forceinline is a compiler built-in, with
the previous define, header inclusion software that detects unnecessary
includes will erroneously flag usages of Compiler.h as unnecessary
(despite being necessary on other platforms). So we define a macro
that's used by Windows and other platforms to ensure this doesn't
happen.
Instead of globbing things under an ambiguous Common.h header, move
compiler-specifics over to Compiler.h. This gives us a dedicated home
for anything related to compilers that we want to make functional across
all compilers that we support.
This moves us a little closer to eliminating Common.h entirely.
As we do lots of writes to *Iptr, the compiler isn't allowed to cache any shared variable (neither index nor Iptr itself).
This commit inlines Iptr + index into the index generator functions, so the compiler know that they are const.
We are used to render them out of order as long as everything else matches, but rendering order does matter, so we have to flush on primitive switch. This commit implements this flush.
Also as we flush on primitive switch, we don't have to create three different index buffers. All indices are now stored in one buffer.
This will slow down games which switch often primitive types (eg ztp), but it should be more accurate.
