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A repository that has original source for patches used in the Arch User Repository package called "mutter-performance". https://aur.archlinux.org/packages/mutter-performance
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Neil Roberts ff11a2b207 Use GL_ARB_texture_swizzle to emulate GL_ALPHA textures
The core profile of GL3 has removed support for component-alpha
textures. Previously the GL3 driver would just ignore this and try to
create them anyway. This would generate a GL error on Mesa.

To fix this the GL texture driver will now create a GL_RED texture
when GL_ALPHA textures are not supported natively. It will then set a
texture swizzle using the GL_ARB_texture_swizzle extension so that the
alpha component will be taken from the red component of the texture.
The swizzle is part of the texture object state so it only needs to be
set once when the texture is created.

The ‘gen’ virtual function of the texture driver has been changed to
also take the internal format as a parameter. The GL driver will now
set the swizzle as appropriate here.

The GL3 driver now reports an error if the texture swizzle extension
is not available because Cogl can't really work properly without out
it. The extension is part of GL 3.3 so it is quite likely that it has
wide support from drivers. Eventually we could get rid of this
requirement if we have our own GLSL front-end and we could generate
the swizzle ourselves.

When uploading or downloading texture data to or from a
component-alpha texture, we can no longer rely on GL to do the
conversion. The swizzle doesn't have any effect on the texture data
functions. In these cases Cogl will now force an intermediate buffer
to be used and it will manually do the conversion as it does for the
GLES drivers.

Reviewed-by: Robert Bragg <robert@linux.intel.com>

(cherry picked from commit 32bacf81ebaa3be21a8f26af07d8f6eed6607652)
2013-01-22 17:48:04 +00:00
build build: Allow to build cogl without an external glib dependency 2013-01-22 17:47:58 +00:00
cogl Use GL_ARB_texture_swizzle to emulate GL_ALPHA textures 2013-01-22 17:48:04 +00:00
cogl-gles2 build: don't include deps/glib headers if glib enabled 2013-01-22 17:47:58 +00:00
cogl-pango Add a GL 3 driver 2013-01-22 17:48:01 +00:00
deps build: fix make dist 2013-01-22 17:48:03 +00:00
doc Add cogl_buffer_map_range() 2013-01-22 17:48:03 +00:00
examples Support window resizing in the SDL 2 winsys 2013-01-22 17:48:04 +00:00
po Added Thai translation 2012-10-15 13:06:21 +07:00
tests tests: Convert test-npot-texture to Cogl 2013-01-22 17:48:04 +00:00
.gitignore build: Allow to build cogl without an external glib dependency 2013-01-22 17:47:58 +00:00
.vimrc misc: Add a .vimrc file 2011-05-17 15:24:54 +01:00
autogen.sh Support building with automake 1.12.x 2012-08-15 13:46:25 +01:00
ChangeLog dist: Don't use elaborate script to gen Changelogs 2011-07-20 16:58:46 +01:00
cogl.doap Adds an initial cogl.doap file 2011-05-06 12:12:13 +01:00
config-custom.h configure: Force #undef of 'near' and 'far' on Windows 2011-06-14 12:14:02 +01:00
config.h.win32.in build: remove unneeded check for libdrm 2012-08-15 17:29:16 +01:00
configure.ac build: Create the libtool file early as it's used by AS_GLIBCONFIG 2013-01-22 17:47:58 +00:00
COPYING Update the COPYING file 2011-09-05 19:02:05 +01:00
Makefile.am build: Allow to build cogl without an external glib dependency 2013-01-22 17:47:58 +00:00
NEWS Updates NEWS for the 1.12.2 release 2013-01-04 17:23:45 +00:00
README.in docs: Update pointers to documentation 2012-09-03 15:55:14 +01:00

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.