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Neil Roberts 2059ae3ac8 Add internal _cogl_push_source to optionally disable legacy state
Some code in Cogl such as when flushing a stencil clip assumes that it
can push a temporary simple pipeline to reset to a known state for
internal drawing operations. However this breaks down if the
application has set any legacy state because that is set globally so
it will also get applied to the internal pipeline.

_cogl_draw_attributes already had an internal flag to disable applying
the legacy state but I think this is quite awkward to use because not
all places that push a pipeline draw the attribute buffers directly so
it is difficult to pass the flag down through the layers.

Conceptually the legacy state is meant to be like a layer on top of
the purely pipeline-based state API so I think ideally we should have
an internal function to push the source without the applying the
legacy state. The legacy state can't be applied as the pipeline is
pushed because the global state can be modified even after it is
pushed. This patch adds a _cogl_push_source() function which takes an
extra boolean flag to mark whether to enable the legacy state. The
value of this flag is stored alongside the pipeline in the pipeline
stack. Another new internal function called
_cogl_get_enable_legacy_state queries whether the top entry in the
pipeline stack has legacy state enabled. cogl-primitives and the
vertex array drawing code now use this to determine whether to apply
the legacy state when drawing. The COGL_DRAW_SKIP_LEGACY_STATE flag is
now removed.

Reviewed-by: Robert Bragg <robert@linux.intel.com>
2011-09-19 16:40:06 +01:00
build build: fix make release-message find the sha256 file 2011-09-05 20:59:00 +01:00
cogl Add internal _cogl_push_source to optionally disable legacy state 2011-09-19 16:40:06 +01:00
cogl-pango build: only have libcogl-pango depend on pango 2011-08-12 15:28:42 +01:00
doc pipeline: split out all layer state apis 2011-09-19 16:40:00 +01:00
examples examples: use $(COGL_PANGO_DEP_LIBS) for cogl-pango users 2011-09-05 19:01:49 +01:00
po l10n: Added Greek translation for cogl 2011-09-18 21:54:31 +03:00
tests test-utils: Use g_setenv instead of setenv 2011-09-19 16:40:06 +01:00
.gitignore egl-gdl: Don't generate cogl-display.h 2011-08-01 16:36:52 +01:00
.vimrc misc: Add a .vimrc file 2011-05-17 15:24:54 +01:00
autogen.sh build: Allow to compile a git checkout without gtk-doc 2011-05-12 11:45:25 +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
configure.ac Starts porting Cogl conformance tests from Clutter 2011-09-08 15:48:07 +01:00
COPYING Update the COPYING file 2011-09-05 19:02:05 +01:00
Makefile.am Starts porting Cogl conformance tests from Clutter 2011-09-08 15:48:07 +01:00
NEWS Updates NEWS for the 1.7.8 release 2011-09-05 19:06:02 +01:00
README.in docs: Update the Bugzilla URL in the README 2011-09-05 20:59:00 +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 to draw
pretty pictures. 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 API references for the latest stable release are available at:

   http://docs.clutter-project.org/docs/cogl/stable/

The experimental 2.0 API can be found here:

   http://docs.clutter-project.org/docs/cogl-2.0-experimental/stable/

   Note: The conflicting "stable" at the end refers to the fact
   to overall Cogl release status, not the documentation specifically.

--
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.