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Neil Roberts 2543a86ba1 cogl-gst-video-sink: Premultiply the colors coming from the video
Commit 99a53c82e9ab0a1e5 removed the internal format argument when
uploading a video frame to a texture so that the format will just be
determined automatically from the image format. However this also
leaves the premultiplied state at the default and the default is TRUE.
That means that when we upload RGBA data Cogl will do a premultiplied
conversion on the CPU. We probably don't want to be putting a CPU
conversion in the way of video frames so this patch changes it to set
the premultiplied state to FALSE on the textures and then do the
premultiplied conversion in the shader.

This is particularly important for AYUV which uses the alpha channel
for the V component so doing a premultiplied conversion on the CPU
just creates garbage and messes up the image.

The RGB and RGBA renderers have each been split into two; one that
uses GLSL and one that uses a regular pipeline. The RGBA pipeline
without GLSL is then changed to use 2 layers so we that we can do the
premultiplied conversion in the second layer with a special layer
combine string.

Reviewed-by: Robert Bragg <robert@linux.intel.com>
(cherry picked from commit 07a57f26596c72507035369c90ed6d62568330b5)
2014-01-31 12:42:03 +00:00
build mingw-fetch-dependencies: Add the -L option when using curl 2014-01-20 16:41:13 +00:00
cogl winsys-wgl: Don't include cogl.h 2014-01-20 16:41:13 +00:00
cogl-gles2 consistently name cogl-gles2 pkg-config files 2014-01-09 16:03:13 +00:00
cogl-gst cogl-gst-video-sink: Premultiply the colors coming from the video 2014-01-31 12:42:03 +00:00
cogl-pango remove internal_format and redundant error arguments 2014-01-09 15:49:47 +00:00
cogl-path cogl-path: Fix the exported symbols regular expression 2014-01-22 13:15:28 +00:00
deps build: fix make dist 2013-01-22 17:48:03 +00:00
doc Tweak documentation for the CoglTexture interface 2014-01-20 14:32:39 +00:00
examples remove internal_format and redundant error arguments 2014-01-09 15:49:47 +00:00
po [l10n] Updated Italian translation. 2013-04-28 19:24:20 +02:00
test-fixtures Add support for RG textures 2014-01-20 14:40:45 +00:00
tests Add support for RG textures 2014-01-20 14:40:45 +00:00
.gitignore Update .gitignore 2013-11-29 14:04:39 +00:00
.vimrc misc: Add a .vimrc file 2011-05-17 15:24:54 +01:00
autogen.sh Add support for automake 1.14 2013-07-03 18:11:53 +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 Update config.h.win32.in 2013-03-15 00:26:35 +08:00
configure.ac Post-release version bump to 1.17.3 2014-01-20 16:59:10 +00:00
COPYING Update the COPYING file 2011-09-05 19:02:05 +01:00
Makefile.am Build and install cogl-path as a shared library 2013-12-11 18:49:19 +00:00
NEWS Updates NEWS for the 1.17.2 release 2014-01-20 16:41:13 +00:00
README.in README: misc updates 2013-07-09 22:54:02 +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:

  • 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:

  • GLib ≥ @GLIB_REQ_VERSION@
     - for gtype integration
  • 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@

The optional Cogl GStreamer library requires:

  • GStreamer 1.0

On X11, Cogl depends on the following extensions

  • XComposite ≥ @XCOMPOSITE_REQ_VERSION@
  • XDamage
  • XExt
  • XFixes ≥ @XFIXES_REQ_VERSION@

For the Wayland backend, Cogl requires:
  • Wayland ≥ @WAYLAND_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 documented here:

  http://cogl3d.org/cogl2-reference/

--
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.