Since we've had several developers from admirable projects say they
would like to use Cogl but would really prefer not to pull in
gobject,gmodule and glib as extra dependencies we are investigating if
we can get to the point where glib is only an optional dependency.
Actually we feel like we only make minimal use of glib anyway, so it may
well be quite straightforward to achieve this.
This adds a --disable-glib configure option that can be used to disable
features that depend on glib.
Actually --disable-glib doesn't strictly disable glib at this point
because it's more helpful if cogl continues to build as we make
incremental progress towards this.
The first use of glib that this patch tackles is the use of
g_return_val_if_fail and g_return_if_fail which have been replaced with
equivalent _COGL_RETURN_VAL_IF_FAIL and _COGL_RETURN_IF_FAIL macros.
Reviewed-by: Neil Roberts <neil@linux.intel.com>
This is to try and improve API consistency. Simple cogl structures that
don't derive from CoglObject and which can be allocated on the stack,
such as CoglColor and CoglMatrix should all have "_init" or
"_init_from" functions to initialize all the structure members. (As
opposed to a cogl_xyz_new() function for CoglObjects). CoglColor
previously used the naming scheme "_set_from" for these initializers but
"_set" is typically reserved for setting individual properties of a
structure/object.
This adds three _init functions:
cogl_color_init_from_4ub
cogl_color_init_from_4f
cogl_color_init_from_4fv
The _set_from functions are now deprecated but only with a gtk-doc
annotation for now. This is because the cogl_color_set_from API is quite
widely used already and so were giving a grace period before enabling a
GCC deprecated warning just because otherwise the MX maintainers will
complain to me that I've made their build logs look messy.
The journal logs colors as 4bytes into a vertex array and since we are
planning to make CoglMaterial track its color using a CoglColor instead
of a byte array this convenience will be useful for re-implementing
_cogl_material_get_colorubv.
We only had getters for the red, green, blue and alpha channels of a
color. This meant that, if you wanted to change, say, the alpha
component of a color, one would need to query the red, green and blue
channels and use set_from_4ub() or set_from_4f().
Instead of this, just provide some setters for CoglColor, using the same
naming scheme than the existing getters.
For some operations on pre-multiplied colors (say, replace the alpha
value), you need to unpremultiply the color.
This patch provides the counterpart to cogl_color_premultiply().
Previously cogl_set_source and cogl_set_source_texture were in
cogl-material.c and the cogl_set_source_color* funcs were in
cogl-color.c. Originally this was because cogl.c was duplicated between
the GL and GLES backends and we didn't want to add to the amount of
duplicated code, but these files have since been consolidated into one
cogl.c.
Since using addresses that might change is something that finally
the FSF acknowledge as a plausible scenario (after changing address
twice), the license blurb in the source files should use the URI
for getting the license in case the library did not come with it.
Not that URIs cannot possibly change, but at least it's easier to
set up a redirection at the same place.
As a side note: this commit closes the oldes bug in Clutter's bug
report tool.
http://bugzilla.openedhand.com/show_bug.cgi?id=521
As part of an incremental process to have Cogl be a standalone project we
want to re-consider how we organise the Cogl source code.
Currently this is the structure I'm aiming for:
cogl/
cogl/
<put common source here>
winsys/
cogl-glx.c
cogl-wgl.c
driver/
gl/
gles/
os/ ?
utils/
cogl-fixed
cogl-matrix-stack?
cogl-journal?
cogl-primitives?
pango/
The new winsys component is a starting point for migrating window system
code (i.e. x11,glx,wgl,osx,egl etc) from Clutter to Cogl.
The utils/ and pango/ directories aren't added by this commit, but they are
noted because I plan to add them soon.
Overview of the planned structure:
* The winsys/ API is the API that binds OpenGL to a specific window system,
be that X11 or win32 etc. Example are glx, wgl and egl. Much of the logic
under clutter/{glx,osx,win32 etc} should migrate here.
* Note there is also the idea of a winsys-base that may represent a window
system for which there are multiple winsys APIs. An example of this is
x11, since glx and egl may both be used with x11. (currently only Clutter
has the idea of a winsys-base)
* The driver/ represents a specific varient of OpenGL. Currently we have "gl"
representing OpenGL 1.4-2.1 (mostly fixed function) and "gles" representing
GLES 1.1 (fixed funciton) and 2.0 (fully shader based)
* Everything under cogl/ should fundamentally be supporting access to the
GPU. Essentially Cogl's most basic requirement is to provide a nice GPU
Graphics API and drawing a line between this and the utility functionality
we add to support Clutter should help keep this lean and maintainable.
* Code under utils/ as suggested builds on cogl/ adding more convenient
APIs or mechanism to optimize special cases. Broadly speaking you can
compare cogl/ to OpenGL and utils/ to GLU.
* clutter/pango will be moved to clutter/cogl/pango
How some of the internal configure.ac/pkg-config terminology has changed:
backendextra -> CLUTTER_WINSYS_BASE # e.g. "x11"
backendextralib -> CLUTTER_WINSYS_BASE_LIB # e.g. "x11/libclutter-x11.la"
clutterbackend -> {CLUTTER,COGL}_WINSYS # e.g. "glx"
CLUTTER_FLAVOUR -> {CLUTTER,COGL}_WINSYS
clutterbackendlib -> CLUTTER_WINSYS_LIB
CLUTTER_COGL -> COGL_DRIVER # e.g. "gl"
Note: The CLUTTER_FLAVOUR and CLUTTER_COGL defines are kept for apps
As the first thing to take advantage of the new winsys component in Cogl;
cogl_get_proc_address() has been moved from cogl/{gl,gles}/cogl.c into
cogl/common/cogl.c and this common implementation first trys
_cogl_winsys_get_proc_address() but if that fails then it falls back to
gmodule.
