Read-only mirror of https://gitlab.gnome.org/GNOME/mutter
2616ae0fa9
This adds a new CoglDriver for GL 3 called COGL_DRIVER_GL3. When requested, the GLX, EGL and SDL2 winsyss will set the necessary attributes to request a forward-compatible core profile 3.1 context. That means it will have no deprecated features. To simplify the explosion of checks for specific combinations of context->driver, many of these conditionals have now been replaced with private feature flags that are checked instead. The GL and GLES drivers now initialise these private feature flags depending on which driver is used. The fixed function backends now explicitly check whether the fixed function private feature is available which means the GL3 driver will fall back to always using the GLSL progend. Since Rob's latest patches the GLSL progend no longer uses any fixed function API anyway so it should just work. The driver is currently lower priority than COGL_DRIVER_GL so it will not be used unless it is specificly requested. We may want to change this priority at some point because apparently Mesa can make some memory savings if a core profile context is used. In GL 3, getting the combined extensions string with glGetString is deprecated so this patch changes it to use glGetStringi to build up an array of extensions instead. _cogl_context_get_gl_extensions now returns this array instead of trying to return a const string. The caller is expected to free the array. Some issues with this patch: • GL 3 does not support GL_ALPHA format textures. We should probably make this a feature flag or something. Cogl uses this to render text which currently just throws a GL error and breaks so it's pretty important to do something about this before considering the GL3 driver to be stable. • GL 3 doesn't support client side vertex buffers. This probably doesn't matter because CoglBuffer won't normally use malloc'd buffers if VBOs are available, but it might but worth making malloc'd buffers a private feature and forcing it not to use them. • GL 3 doesn't support the default vertex array object. This patch just makes it create and bind a single non-default vertex array object which gets used just like the normal default object. Ideally it would be good to use vertex array objects properly and attach them to a CoglPrimitive to cache the state. Reviewed-by: Robert Bragg <robert@linux.intel.com> (cherry picked from commit 66c9db993595b3a22e63f4c201ea468bc9b88cb6) |
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| cogl-pango | ||
| deps | ||
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| examples | ||
| po | ||
| tests | ||
| .gitignore | ||
| .vimrc | ||
| autogen.sh | ||
| ChangeLog | ||
| cogl.doap | ||
| config-custom.h | ||
| config.h.win32.in | ||
| configure.ac | ||
| COPYING | ||
| Makefile.am | ||
| NEWS | ||
| README.in | ||
README for Cogl @COGL_1_VERSION@
===============================================================================
Note: This file is delimited with -- markers so it is possible to split
sections out for other purposes, such as for release notes.
--
DESCRIPTION
-------------------------------------------------------------------------------
Cogl is a small open source library for using 3D graphics hardware for
rendering. The API departs from the flat state machine style of OpenGL and is
designed to make it easy to write orthogonal components that can render without
stepping on each others toes.
As well as aiming for a nice API, we think having a single library as opposed
to an API specification like OpenGL has a few advantages too; like being
able to paper over the inconsistencies/bugs of different OpenGL
implementations in a centralized place, not to mention the myriad of OpenGL
extensions. It also means we are in a better position to provide utility
APIs that help software developers since they only need to be implemented
once and there is no risk of inconsistency between implementations.
Having other backends, besides OpenGL, such as drm, Gallium or D3D are
options we are interested in for the future.
--
REQUIREMENTS
-------------------------------------------------------------------------------
Cogl currently only requires:
• GLib ≥ @GLIB_REQ_VERSION@
• OpenGL ≥ 1.3 (or 1.2 + multitexturing), or OpenGL ES 2.0 (or 1.1)
• GLX, AGL, WGL or an EGL implementation
Cogl also has optional dependencies:
• GDK-Pixbuf ≥ @GDK_PIXBUF_REQ_VERSION@
- for image loading
• Cairo ≥ @CAIRO_REQ_VERSION@
- for debugging texture atlasing (debug builds only)
The optional Cogl Pango library requires:
• Cairo ≥ @CAIRO_REQ_VERSION@
• PangoCairo ≥ @PANGOCAIRO_REQ_VERSION@
On X11, Cogl depends on the following extensions
• XComposite ≥ @XCOMPOSITE_REQ_VERSION@
• XDamage
• XExt
• XFixes ≥ @XFIXES_REQ_VERSION@
When running with OpenGL, Cogl requires at least version 1.3
or 1.2 with the multitexturing extension. However to build Cogl
you will need the latest GL headers which can be obtained from:
http://www.khronos.org
If you are building the API reference you will also need:
• GTK-Doc ≥ @GTK_DOC_REQ_VERSION@
If you are building the additional documentation you will also need:
• xsltproc
• jw (optional, for generating PDFs)
If you are building the Introspection data you will also need:
• GObject-Introspection ≥ @GI_REQ_VERSION@
GObject-Introspection is available from:
git://git.gnome.org/gobject-introspection
If you want support for profiling Cogl you will also need:
• UProf ≥ @UPROF_REQ_VERSION@
UProf is available from:
git://github.com/rib/UProf.git
--
DOCUMENTATION
-------------------------------------------------------------------------------
The 1.x stable API is documented here:
http://developer.gnome.org/cogl/stable/
The 1.x development API is documented here:
http://developer.gnome.org/cogl/1.$(COGL_1_MINOR_VERSION)
The experimental 2.0 API is currently not hosted online but can be built
by passing the --enable-gtk-doc option to ./configure when building
and the documentation can then be found under
doc/reference/cogl-2.0-experimental/html/index.html
--
LICENSE
-------------------------------------------------------------------------------
Most of Cogl is licensed under the terms of the GNU Lesser General Public
License, version 2.1 or (at your option) later. Some files are licensed under
more permissive licenses MIT or BSD style licenses though so please see
individual files for details.
--
BUILDING AND INSTALLATION
-------------------------------------------------------------------------------
Please refer to the INSTALL document.
--
BUGS
-------------------------------------------------------------------------------
Please report bugs here:
http://bugzilla.gnome.org/enter_bug.cgi?product=cogl
You will need a Bugzilla account.
Please include the following in bug reports:
• what system you're running Cogl on;
• which version of Cogl you are using;
• which version of GLib and OpenGL (or OpenGL ES) you are using;
• which video card and which drivers you are using, including output of
glxinfo and xdpyinfo (if applicable);
• how to reproduce the bug.
If you cannot reproduce the bug with one of the tests that come with
Cogl's source code, it can help a lot to include a small test case
displaying the bad behaviour.
If the bug exposes a crash, the exact text printed out and a stack trace
obtained using gdb are greatly appreciated.
--
CONTRIBUTING
-------------------------------------------------------------------------------
The CODING_STYLE file describes the coding style we use throughout Cogl,
please try your best to conform to this style because the consistency
really helps keep the code maintainable.
We can accept contributions in several ways:
• Either as patches attached to bugs on bugzilla
- For this you may be interested in using git-bz.
See http://git.fishsoup.net/man/git-bz.html for details
• You can email us patches
- For this we recommend using git-send-email
• You can create a remote branch and ask us to pull from that for more
substantial changes.
- For this we recommend using github.
Ideally standalone patches should be created using git format-patch since
that makes it easiest to import the patch with a commit message into a
git repository.