Yeah, sorry, I know, the enums are renamed for second or third time in a
row, first they were Image::Format, then ImageFormat, then ColorFormat
and now PixelFormat. But this time it's final and last time they are
renamed and now everything is finally consistent:
* ColorFormat::DepthComponent -- depth is not a color, thus
PixelFormat::DepthComponent makes a lot more sense.
* There will be PixelStorage classes, which will be stored in images
alonside PixelFormat/PixelType enums, making everything nicely
aligned.
* The GL documentation about glTexImage2D() etc. denotes the <format>
and <type> parameters as format and type of *pixel* data, so now we
are _finally_ consistent with the official naming.
I wonder why did I not choose PixelFormat originally. Anyway, the old
<Magnum/ColorFormat.h> header, ColorFormat, ColorType and
CompressedColorFormat types are now aliases to the new ones, are marked
as deprecated and will be removed in some future release (as always, I'm
waiting at least six months before removing the deprecated
functionality).
It is superseded by core functionality. The only annoyance is that you
need to use TextureFormat::SRGB in ES2 and TextureFormat::SRGB8 in ES3,
but that's with many other formats anyway. Also apparently the unsized
format is still allowed in core desktop GL, which is a shame.
It makes sense, but this ordering also helps to avoid bug in Doxygen
1.8.6+ which merges next non-xrefitem section with the previous one (so
e.g. the TODO list contained the following @see block, which is not
desired).
The only places where they aren't absolute are:
- when header is included from corresponding source file
- when including headers which are not part of final installation (e.g.
test-specific configuration, headers from Implementation/)
Everything what was in src/ is now in src/Corrade, everything from
src/Plugins is now in src/MagnumPlugins, everything from external/ is in
src/MagnumExternal. Added new CMakeLists.txt file and updated the other
ones for the moves, no other change was made. If MAGNUM_BUILD_DEPRECATED
is set, everything compiles and installs like previously except for the
plugins, which are now in MagnumPlugins and not in Magnum/Plugins.
Until recently (or maybe not too recently) ES3 extension header was
"currently empty", now the extension header is shared with ES2. It's
nice to finally get rid of all the weird ifndefs.
Removed all known GLEW workarounds, added one small workaround for
missing ARB_texture_compression_bptc. I didn't want to patch glLoadGen
for just four enum values, this way it's possible to use stock one
without any patching (except for missing OpenGL 2.1 support, as stated
in external/OpenGL/GL/README.md).
As one file now replaces both `glew.h` and `glcorearb.h` and it has the
same size as `glcorearb.h` alone , it saves approximately 18k LOC,
resulting in 15 second shorter compilation time (5:03 before, 4:48 now).
Not bad.
Separated EXT_framebuffer_object, EXT_framebuffer_blit,
EXT_framebuffer_multisample and EXT_packed_depth_stencil don't have the
same functionality as ARB_framebuffer_object (e.g. missing
GL_FRAMEBUFFER_UNDEFINED in glCheckFramebufferStatus()) and separated
read/draw binding is only in EXT_framebuffer_blit, which complicates the
internals.
Checked with Mesa 8/9 and OpenGL 2.1, current one has
ARB_framebuffer_object and also all these four, Mesa 7.7 didn't have
EXT_framebuffer_multisample, but that's a long time ago, so not
supporting these separate extensions shouldn't be an issue.
The problem with unavailable separate binding points remains on OpenGL
ES 2.0, there are three different extensions bringing that
functionality, thus the code managing the available binding points
remains there.
Special RGB values together, RGBA values together, Depth values
together, DepthStencil values together. Left sized internal formats in
the same order, though.
It is deprecated, but many ES2 implementations don't support
EXT_texture_rg, thus this is the only way to have single- and
two-component textures without wasting precious memory. The enum value
isn't exposed on desktop OpenGL and ES3. GL_ALPHA is not supported, as
it doesn't bring any new functionality (it is also single-component
and thus can be interchanged with GL_LUMINANCE).
Advantages:
* The enums were large (600-800 lines) and they polluted the header,
now they are in separate files (except for BufferTexture, which has
the enum small enough to be left in the same file).
* Image classes now don't need to include OpenGL headers, as they were
needed only for the enum values. With advantage of C++11's forward
enum declarations there is no need to include the enum headers
anywhere in implementation, only when particular values are needed.
* The values are now less verbose:
AbstractTexture::InternalFormat::RGB8 // before
TextureFormat::RGB8 // now
* Resolved another "trivial choice" problem (thanks @JanDupal for
introducing this term to me): how to specify the format if there are
ten ways to do it (some being massively confusing):
Image2D::Format f = AbstractImage::Format::RGB; // too long...
Image2D::Format f = Image3D::Format::RGBA; // why 3D? this works?
Image2D::Format f = BufferImage1D::Format::RGBA; // wat?
It is even worse (and more verbose) with textures:
Texture2D::InternalFormat f =
CubeMapTextureArray::InternalFormat::RGB8; // this is allowed?
To have consistent naming this change was done also with
BufferTexture::InternalFormat (now BufferTextureFormat), although there
were no trivial choice issues and the enum isn't too large. But at least
it is now less typing.
Vladimír Vondruš