The indexed binding is allowed for only some types (atomic counters,
uniforms, shader storage and transform feedback), thus we need separate
enum for that. Because the bind() function will be used far more often
than setTargetHint(), the original Target enum is now renamed to
TargetHint and the new Target enum contains (in non-deprecated build)
only three values.
For backwards compatibility, though, we need to have all original Target
values, thus the new Target enum contains also all other values from
TargetHint, but they are marked as deprecated and (at least) run-time
checked in bind() so they aren't accidentaly used for indexed binding.
Similarly there are also deprecated Target overloads of Buffer() and
setTargetHint(). It's ugly, but hopefully will suffice for now. This mess
will be removed as soon as possible in some upcoming version.
The documentation of ARB_invalidate_subdata mentions that all the
functions are really just a hint for the implementation to make some
performance optimizations and they are not affecting behavior at all. So
it's perfectly fine to do nothing if the extension is not supported.
I didn't do this originally as I mistakenly thought that invalidating
depth buffer would somehow behave the same as clearing it, but that's
not the case.
In most cases the label is set directly from code, e.g.:
texture.setLabel("diffuse-duck");
Avoiding conversion to std::string and passing char(&)[size] directly
will avoid one allocation and deallocation. Better solution would be to
use std::string_view everywhere, but we're not in C++17 yet.
A general way to detect drivers, which can be later used for applying
driver-specific workarounds. Currently used for disabling
ARB_explicit_uniform_location on AMD drivers.
In OpenGL ES this is implemented in EXT_multi_draw_arrays extension, if
it is not available, the functionality is emulated using sequence of
normal draw() calls.
Functionality provided by GL 3.3 and ARB_instanced_arrays, on ES2 this
is again implemented in three different extensions --
{ANGLE,EXT,NV}_instanced_arrays. They are disabled until Magnum has
proper extension loading on ES.
On desktop GL this is provided by ARB_draw_instanced (GL 3.1). Base
instance is available only on desktop GL (4.2, ARB_base_instance). In
ES2 the instanced functionality is provided by three (!) different
extensions (ANGLE_instanced_arrays, EXT_draw_instanced,
NV_draw_instanced), the proper implementation is chosen on context
creation based on what extension is available. Though we don't have
extension loader for ES yet, thus all these extensions are disabled and
the implementation has assertion in it.
Added blind test which tests only that something has been drawn and no
errors were emitted, but not whether the right command is used. I'll
probably need to check this later, because the Mesh::draw() behemoth is
going slightly out of hand :)
Until we have proper extension loader implemented (caused
FramebufferGLTest to assert).
On a related note, NVidia drivers 334.21 support *a lot* of ES2
extensions. Wow.
Until now the textures were bound to layers, which was rather confusing,
especially when binding layered textures to layers (gaah). Also the
wording might have implied that each texture must be in some layer in
order to make it usable in shader. This is no longer the case with (yet
unimplemented) bindless texture, so another reason to remove the
confusion.
All occurences of texture layers were replaced texture binding units to
follow OpenGL naming. It was mostly in the docs, except for
already-deprecated *Layer enums in shaders, but they will be removed
soon anyway.
Previously the extensions were either disabled altogether (e.g. because
we don't have yet extension wrangler on ES) or had manually adjusted
minimal required versions to avoid issues on older versions (e.g.
ARB_explicit_attrib_location is known to give compiler errors when used
with GLSL < 1.50 on some drivers), both done basically at compile time
unrelated to actual hardware/driver used.
Now all the extensions are enabled exactly as the driver advertises them
(or when their core version is not larger than the context version) and
have minimal required versions as per specification. Given extension is
supported in given version when it is marked as such and its minimal
required version is not larger than the requested one. The extension
disabling is thus done by simply increasing the minimal required version
to larger value (or Version::None for disabling it for all versions).
Currently no such disabling is put into place, but the existing
workarounds scattered all over the place will be gradually converted to
this.
Simplified the code and tests by marking all extensions from previous
versions as supported instead of additional "shorthand" checking whether
extension's core version is supported. The check wasn't probably much of
a speedup, as it was just another branch. This was also buggy
previously, because when the extension would be reported as not being
supported in older versions, which is not what we want. Hopefully this
won't reintroduce the numerous issues with Mesa and OSX I had in the
past :-)
Also removed duplicate implementation of
Context::isExtensionSupported(), one overload is now calling the other.
Also added (currently disabled) ES implementation (provided by
EXT_separate_shader_objects). Unfortunately it's not possible to reduce
the function count, because ARB_separate_shader_objects and
EXT_direct_state_access are completely independent. Also double uniforms
are supported since GL 4.0 and SSO are since 4.1, so we can't omit
old glUniform*() calls for doubles either.
The previous way was half-working at best, as it handled array textures
improperly. Now there is overload for each texture type. The old way
with attachTexture*D() is marked as deprecated and will be removed in
future release.
Vladimír Vondruš