Ah the good old times where my brain was not overflowing with
unnecessarily deep knowledge about how GPUs (and OpenGL drivers in
particular) work. Nope, switching a blend state and calling glFinish()
won't generate any GPU work, that will be all deferred until there's
something to be actually drawn, cleared or copied.
'cuz I was writing some raw GL for Emscripten tests and arrived at
glClear(GL_COLOR);
without having any suspicion that this is just TOTALLY WRONG. Same
would go for Vulkan few years ahead when I'm so used to the Magnum
wrappers that I forget what the common pitfalls are.
There are no SSO / DSA extensions on that platform, so it doesn't make
sense to do this extra indirection. Saves another kilobyte (237 -> 236
kB) in WebGL 2 magnum-gl-info.wasm.
Instead of wrapping glProgramUniform*() inside a member function, we now
call that function directly, which allows us to remove 2/3rds of
AbstractShaderProgram members. The non-DSA code path is still
implemented though member functions, though they are now static,
mimic the signature of the DSA APIs and do a use() + glUniform*()
internally.
With this flag set (which is done implicitly for all windowless apps
and, conversely, not done for all windowed apps), the default
framebuffer state isn't touched in any way, which should avoid potential
race conditions with default framebuffer on another thread.
This means that instead of 12 separate allocations we have just one,
allocating everything together in a contiguous piece of memory. That
should be also a bit more cache friendly when accessing the state as
it's not scattered around the memory like crazy.
Because there are no Pointer indirections needed anymore, the State
members are just references now. That resulted in a lot of sweeping
changes around the whole GL library, but they're all trivial, changing
`->` to `.`, mostly.
There's two more nested allocations in the TextureState struct, will
take care of them in a separate commit.
I don't see a real use case for this API (and don't remember ever using
it) and it only causes extra overhead during context creation (and then
a ton of useless allocations at runtime).
Broken since 0ceb54ed7d, but the two code
paths actually differ only by an enum name so it didn't cause any
crashes. (I wonder why I need two different code paths at all.)
Disabling engine startup log or modifying enabled extensions /
workarounds from the application side was one of the common pain
points and this should *finally* solve the problem. This Configuration
is now inherited by the usual Platform::*Application::GLConfiguration /
Platform::Windowless*Application::Configuration classes people are used
to, so for the end user it's just as if these classes got a bunch new
options.
Having this, I also extended the ContextGLTest to verify that the
Configuration and command-line options do what's expected because that
hadn't automated tests until now. The test is mostly a copy of what I
did for Vulkan already, nothing special. Additionally all
Platform*ApplicationTest executables gained a new --quiet option to
verify that the GL::Context::Configuration subset gets correctly passed
from the Application code, because that's something we can't really
verify in an automated way.
StringViews are great -- given that they are trivially destructible, the
compiler can now tell me that I have unused variables. If it wouldn't be
trivially destructible (like std::string), the destructor is treated as
if it has side-effects so the compiler won't complain.
Ew. At first I tried to just port a growable Array of StringViews (which
would already save quite a lot), but then I realized I have a clear
upper bound on the extensions and so can use a "counting sort" without
having to deduplicate anything after.
After the previous (rather minimal) reduction by the Context cleanup,
this reduces the size of magnum-gl-info.wasm from 245 to 237 kB. Quite
significant, I'd say!
These are in most cases the only strings that are used, and I don't
think having to call std::strlen() for each of them is a good idea if
we don't need to.
We're going to eventually include this class in all Application classes
(need that in order to inherit a to-be-created Configuration class) and
the <string> and <vector> would be just too much. This change caused
magnum-gl-info.wasm (WebGL 2 build) to go down from 247 to 245 kB. Not
much, but that's I guess because there's still a lot other vectors of
strings elsewhere.
There's a lot more places to clean up, will do those in separate
commits. This change is the most atomic I could do, and it introduces a
breaking change to all APIs that returned a std::vector or a
std::string. Fortunately (or as I hope) those weren't used that much, so
it shouldn't cause build breakages for that many people.
Quite a lot of the optimization ideas is borrowed from the new Vk
library -- such as "interning" the driver workaround strings to avoid
allocating their copies.
This was done silently until now and I think such platform-specific code
should be always exposed as a disableable workaround. Moreover, I need a
similar thing for ANGLE, so this comes handy.
Needed a change in flextGL to allow merging in 3rd party gl.xml
additions because Chrome is apparently a center of the universe and thus
doesn't need to bother upstreaming its extensions, ffs.
Apparently "pixel size" could have meant "image size in pixels" as well.
Additionally also clarify what image size means, since it might be
unclear especially for the block-compressed images.
An unqualified link to Extensions.h will, guess what -- pick the last
Extension.h header that Doxygen came across. So in this case
Magnum/Vk/Extensions.h. With no warning or any other hint that something
MAYBE could be wrong. FFS.
Vladimír Vondruš