Commit Graph

132 Commits

Author SHA1 Message Date
Robert Bragg
df21e20f65 Adds CoglError api
Although we use GLib internally in Cogl we would rather not leak GLib
api through Cogl's own api, except through explicitly namespaced
cogl_glib_ / cogl_gtype_ feature apis.

One of the benefits we see to not leaking GLib through Cogl's public API
is that documentation for Cogl won't need to first introduce the Glib
API to newcomers, thus hopefully lowering the barrier to learning Cogl.

This patch provides a Cogl specific typedef for reporting runtime errors
which by no coincidence matches the typedef for GError exactly.  If Cogl
is built with --enable-glib (default) then developers can even safely
assume that a CoglError is a GError under the hood.

This patch also enforces a consistent policy for when NULL is passed as
an error argument and an error is thrown. In this case we log the error
and abort the application, instead of silently ignoring it. In common
cases where nothing has been implemented to handle a particular error
and/or where applications are just printing the error and aborting
themselves then this saves some typing. This also seems more consistent
with language based exceptions which usually cause a program to abort if
they are not explicitly caught (which passing a non-NULL error signifies
in this case)

Since this policy for NULL error pointers is stricter than the standard
GError convention, there is a clear note in the documentation to warn
developers that are used to using the GError api.

Reviewed-by: Neil Roberts <neil@linux.intel.com>

(cherry picked from commit b068d5ea09ab32c37e8c965fc8582c85d1b2db46)

Note: Since we can't change the Cogl 1.x api the patch was changed to
not rename _error_quark() functions to be _error_domain() functions and
although it's a bit ugly, instead of providing our own CoglError type
that's compatible with GError we simply #define CoglError to GError
unless Cogl is built with glib disabled.

Note: this patch does technically introduce an API break since it drops
the cogl_error_get_type() symbol generated by glib-mkenum (Since the
CoglError enum was replaced by a CoglSystemError enum) but for now we
are assuming that this will not affect anyone currently using the Cogl
API. If this does turn out to be a problem in practice then we would be
able to fix this my manually copying an implementation of
cogl_error_get_type() generated by glib-mkenum into a compatibility
source file and we could also define the original COGL_ERROR_ enums for
compatibility too.

Note: another minor concern with cherry-picking this patch to the 1.14
branch is that an api scanner would be lead to believe that some APIs
have changed, and for example the gobject-introspection parser which
understands the semantics of GError will not understand the semantics of
CoglError. We expect most people that have tried to use
gobject-introspection with Cogl already understand though that it is not
well suited to generating bindings of the Cogl api anyway and we aren't
aware or anyone depending on such bindings for apis involving GErrors.
(GnomeShell only makes very-very minimal use of Cogl via the gjs
bindings for the cogl_rectangle and cogl_color apis.)

The main reason we have cherry-picked this patch to the 1.14 branch
even given the above concerns is that without it it would become very
awkward for us to cherry-pick other beneficial patches from master.
2013-01-22 17:47:39 +00:00
Damien Lespiau
eb92b512c6 core: Don't initialize the GType system with --disable-glib
--disable-glib also defines COGL_HAS_GTYPE_SUPPORT to #ifdef out GType
support in cogl. This also means we don't want to initialize glib's type
system in that case.

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

(cherry picked from commit 67ad777099d62bdbc8515f6ee58ed80429cc6496)
2013-01-22 17:47:24 +00:00
Damien Lespiau
24fa64bea2 core: Don't use g_once_*() API
As Cogl is not thread safe, we don't really need a thread safe
cogl_init() function.

This also reduces the amount of dependency cogl has on glib, handy when
we want to create a standalone version of cogl, some day.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
(cherry picked from commit 429e49e3028a425eb198d8969dfbf57790e2e72a)
2013-01-18 17:28:25 +00:00
Neil Roberts
df77e8565e Don't use eglGetProcAddress to retrieve core functions
According to the EGL spec, eglGetProcAddress should only be used to
retrieve extension functions. It also says that returning non-NULL
does not mean the extension is available so you could interpret this
as saying that the function is allowed to return garbage for core
functions. This seems to happen at least for the Android
implementation of EGL.

To workaround this the winsys's are now passed down a flag to say
whether the function is from the core API. This information is already
in the gl-prototypes headers as the minimum core GL version and as a
pair of flags to specify whether it is available in core GLES1 and
GLES2. If the function is in core the EGL winsys will now avoid using
eglGetProcAddress and always fallback to querying the library directly
with the GModule API.

The GLX winsys is left alone because glXGetProcAddress apparently
supports querying core API and extension functions.

The WGL winsys could ideally be changed because wglGetProcAddress
should also only be used for extension functions but the situation is
slightly different because WGL considers anything from GL > 1.1 to be
an extension so it would need a bit more information to determine
whether to query the function directly from the library.

The SDL winsys is also left alone because it's not as easy to portably
determine which GL library SDL has chosen to load in order to resolve
the symbols directly.

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

(cherry picked from commit 72089730ad06ccdd38a344279a893965ae68cec1)

  Since we aren't able to break API on the 1.12 branch
  cogl_get_proc_address is still supported but isn't easily able to
  determine whether the given name corresponds to a core symbol or
  not.  For now we just assume the symbol being queried isn't part
  of the core GL api and update the documentation accordingly.
2012-08-06 14:27:45 +01:00
Robert Bragg
e3d6bc36d3 Re-design the matrix stack using a graph of ops
This re-designs the matrix stack so we now keep track of each separate
operation such as rotating, scaling, translating and multiplying as
immutable, ref-counted nodes in a graph.

Being a "graph" here means that different transformations composed of
a sequence of linked operation nodes may share nodes.

The first node in a matrix-stack is always a LOAD_IDENTITY operation.

As an example consider if an application where to draw three rectangles
A, B and C something like this:

cogl_framebuffer_scale (fb, 2, 2, 2);
cogl_framebuffer_push_matrix(fb);

  cogl_framebuffer_translate (fb, 10, 0, 0);

  cogl_framebuffer_push_matrix(fb);

    cogl_framebuffer_rotate (fb, 45, 0, 0, 1);
    cogl_framebuffer_draw_rectangle (...); /* A */

  cogl_framebuffer_pop_matrix(fb);

  cogl_framebuffer_draw_rectangle (...); /* B */

cogl_framebuffer_pop_matrix(fb);

cogl_framebuffer_push_matrix(fb);
  cogl_framebuffer_set_modelview_matrix (fb, &mv);
  cogl_framebuffer_draw_rectangle (...); /* C */
cogl_framebuffer_pop_matrix(fb);

That would result in a graph of nodes like this:

LOAD_IDENTITY
      |
    SCALE
    /     \
SAVE       LOAD
  |           |
TRANSLATE    RECTANGLE(C)
  |     \
SAVE    RECTANGLE(B)
  |
ROTATE
  |
RECTANGLE(A)

Each push adds a SAVE operation which serves as a marker to rewind too
when a corresponding pop is issued and also each SAVE node may also
store a cached matrix representing the composition of all its ancestor
nodes. This means if we repeatedly need to resolve a real CoglMatrix
for a given node then we don't need to repeat the composition.

Some advantages of this design are:
- A single pointer to any node in the graph can now represent a
  complete, immutable transformation that can be logged for example
  into a journal. Previously we were storing a full CoglMatrix in
  each journal entry which is 16 floats for the matrix itself as well
  as space for flags and another 16 floats for possibly storing a
  cache of the inverse. This means that we significantly reduce
  the size of the journal when drawing lots of primitives and we also
  avoid copying over 128 bytes per entry.
- It becomes much cheaper to check for equality. In cases where some
  (unlikely) false negatives are allowed simply comparing the pointers
  of two matrix stack graph entries is enough. Previously we would use
  memcmp() to compare matrices.
- It becomes easier to do comparisons of transformations. By looking
  for the common ancestry between nodes we can determine the operations
  that differentiate the transforms and use those to gain a high level
  understanding of the differences. For example we use this in the
  journal to be able to efficiently determine when two rectangle
  transforms only differ by some translation so that we can perform
  software clipping.

Reviewed-by: Neil Roberts <neil@linux.intel.com>

(cherry picked from commit f75aee93f6b293ca7a7babbd8fcc326ee6bf7aef)
2012-08-06 14:27:40 +01:00
Robert Bragg
54735dec84 Switch use of primitive glib types to c99 equivalents
The coding style has for a long time said to avoid using redundant glib
data types such as gint or gchar etc because we feel that they make the
code look unnecessarily foreign to developers coming from outside of the
Gnome developer community.

Note: When we tried to find the historical rationale for the types we
just found that they were apparently only added for consistent syntax
highlighting which didn't seem that compelling.

Up until now we have been continuing to use some of the platform
specific type such as gint{8,16,32,64} and gsize but this patch switches
us over to using the standard c99 equivalents instead so we can further
ensure that our code looks familiar to the widest range of C developers
who might potentially contribute to Cogl.

So instead of using the gint{8,16,32,64} and guint{8,16,32,64} types this
switches all Cogl code to instead use the int{8,16,32,64}_t and
uint{8,16,32,64}_t c99 types instead.

Instead of gsize we now use size_t

For now we are not going to use the c99 _Bool type and instead we have
introduced a new CoglBool type to use instead of gboolean.

Reviewed-by: Neil Roberts <neil@linux.intel.com>

(cherry picked from commit 5967dad2400d32ca6319cef6cb572e81bf2c15f0)
2012-08-06 14:27:39 +01:00
Neil Roberts
d18b59d9e6 Add a public cogl_bitmap_new_for_data
This creates a CoglBitmap which points into an existing buffer in
system memory. That way it can be used to create a texture or to read
pixel data into. The function replaces the existing internal function
_cogl_bitmap_new_from_data but removes the destroy notify call back.
If the application wants notification of destruction it can just use
the cogl_object_set_user_data function as normal. Internally there is
now a convenience function to create a bitmap for system memory and
automatically free the buffer using that mechanism.

The name of the function is inspired by
cairo_image_surface_create_for_data which has similar semantics.

Reviewed-by: Robert Bragg <robert@linux.intel.com>
2012-03-14 12:19:56 +00:00
Ryan Lortie
6f59993e1b Move the fallback define for GL_PACK_INVERT_MESA
The if-undefined fallback declaration for GL_PACK_INVERT_MESA was
originally added in cogl.c along with code to use it (as part of commit
6f79eb8a5a).  Later on, commit
10a38bb14f moved the code that used it to
cogl-framebuffer.c but didn't move the define along with it.  Do that
now.

https://bugzilla.gnome.org/show_bug.cgi?id=672038

Reviewed-by: Neil Roberts <neil@linux.intel.com>
2012-03-14 12:14:24 +00:00
Neil Roberts
2196518b00 Don't export cogl_gl_error_to_string
This is only used internally when debugging is enabled to give a
human-readable name to a GL error so we shouldn't be exporting it
outside of the library. This just adds an underscore to the symbol
name. This shouldn't end up removing any public symbols from the 1.9.8
release because by default a non-git build disables debug so it wasn't
exported anyway.

Reviewed-by: Robert Bragg <robert@linux.intel.com>
2012-03-09 16:40:42 +00:00
Neil Roberts
185630085c Add -Wmissing-declarations to maintainer flags and fix problems
This option to GCC makes it give a warning whenever a global function
is defined without a declaration. This should catch cases were we've
defined a function but forgot to put it in a header. In that case it
is either only used within one file so we should make it static or we
should declare it in a header.

The following changes where made to fix problems:

• Some functions were made static

• cogl-path.h (the one containing the 1.0 API) was split into two
  files, one defining the functions and one defining the enums so that
  cogl-path.c can include the enum and function declarations from the
  2.0 API as well as the function declarations from the 1.0 API.

• cogl2-clip-state has been removed. This only had one experimental
  function called cogl_clip_push_from_path but as this is unstable we
  might as well remove it favour of the equivalent cogl_framebuffer_*
  API.

• The GLX, SDL and WGL winsys's now have a private header to define
  their get_vtable function instead of directly declaring in the C
  file where it is called.

• All places that were calling COGL_OBJECT_DEFINE need to have the
  cogl_is_whatever function declared so these have been added either
  as a public function or in a private header.

• Some files that were not including the header containing their
  function declarations have been fixed to do so.

• Any unused error quark functions have been removed. If we later want
  them we should add them back one by one and add a declaration for
  them in a header.

• _cogl_is_framebuffer has been renamed to cogl_is_framebuffer and
  made a public function with a declaration in cogl-framebuffer.h

• Similarly for CoglOnscreen.

• cogl_vdraw_indexed_attributes is called
  cogl_framebuffer_vdraw_indexed_attributes in the header. The
  definition has been changed to match the header.

• cogl_index_buffer_allocate has been removed. This had no declaration
  and I'm not sure what it's supposed to do.

• CoglJournal has been changed to use the internal CoglObject macro so
  that it won't define an exported cogl_is_journal symbol.

• The _cogl_blah_pointer_from_handle functions have been removed.
  CoglHandle isn't used much anymore anyway and in the few places
  where it is used I think it's safe to just use the implicit cast
  from void* to the right type.

• The test-utils.h header for the conformance tests explicitly
  disables the -Wmissing-declaration option using a pragma because all
  of the tests declare their main function without a header. Any
  mistakes relating to missing declarations aren't really important
  for the tests.

• cogl_quaternion_init_from_quaternion and init_from_matrix have been
  given declarations in cogl-quaternion.h

Reviewed-by: Robert Bragg <robert@linux.intel.com>
2012-03-06 18:45:44 +00:00
Neil Roberts
10a38bb14f Add a public cogl_framebuffer_read_pixels_into_bitmap
This adds a public function to read pixels from a framebuffer into a
CoglBitmap. This replaces the internal function
_cogl_read_pixels_with_rowstride because a CoglBitmap contains a
rowstride so it can be used for the same purpose. A CoglBitmap already
has public API to make one that points to a CoglPixelBuffer so this
function can be used to read pixels into a PBO. It also avoids the
need to push the framebuffer on to the context's stack so it provides
a function which can be used in the 2.0 API after the stack is
removed.

Reviewed-by: Robert Bragg <robert@linux.intel.com>
2012-03-05 18:16:10 +00:00
Neil Roberts
031dd661c0 bitmap: Add a function to convert into an existing buffer
This adds _cogl_bitmap_convert_into_bitmap which is the same as
_cogl_bitmap_convert except that it writes into an existing bitmap
instead of allocating a new one. _cogl_bitmap_convert now just
allocates a buffer and calls the new function. This is used in
_cogl_read_pixels to avoid allocating a second intermediate buffer
when the pixel format to store in is not GL_RGBA.

Reviewed-by: Robert Bragg <robert@linux.intel.com>
2012-03-05 17:46:57 +00:00
Neil Roberts
f4cd5aceb9 _cogl_bitmap_convert: Also handle premult conversions
If we are going to unpack the data into a known format anyway we might
as well do the premult conversion instead of delaying it to do
in-place. This helps because not all formats with alpha channels are
handled by the in-place premult conversion code. This removes the
_cogl_bitmap_convert_format_and_premult function so that now
_cogl_bitmap_convert is a completely general purpose function that can
convert from anything to anything. _cogl_bitmap_convert now includes a
fast path for when the base formats are the same and the premult
conversion can be handled with the in-place code so that we don't need
to unpack and can just copy the bitmap instead.

Reviewed-by: Robert Bragg <robert@linux.intel.com>
2012-03-05 17:44:52 +00:00
Neil Roberts
323adc0c14 Avoid making up the format COGL_PIXEL_FORMAT_A_8_PRE
There are a few places in Cogl that try to set the premult bit on a
pixel format depending on whether it has an alpha channel. However
this breaks if the pixel format is alpha-only because premultiplying
data without any RGB components doesn't make any sense. This adds an
internal macro to check for cases where we should add the premult bit
called COGL_PIXEL_FORMAT_CAN_HAVE_PREMULT. This now gets used in all
places that previously just checking for COGL_A_BIT.

https://bugzilla.gnome.org/show_bug.cgi?id=671016

Reviewed-by: Robert Bragg <robert@linux.intel.com>
2012-03-05 17:43:46 +00:00
Robert Bragg
680f63a48c Remove all internal includes of cogl.h
The cogl.h header is meant to be the public header for including the 1.x
api used by Clutter so we should stop using that as a convenient way to
include all likely prototypes and typedefs. Actually we already do a
good job of listing the specific headers we depend on in each of the .c
files we have so mostly this patch just strip out the redundant
includes for cogl.h with a few fixups where that broke the build.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
2012-02-20 23:12:45 +00:00
Damien Leone
f3fa86b482 Add 30-bit color depth pixel formats X101010 and 2101010
30-bit color depth formats are defined by using value 13 in the least
significant nibble of the pixel format enumeration. This nibble
encodes bytes-per-pixel and byte alignment.

The _cogl_pixel_format_get_bytes_per_pixl() function is updated
accordingly to support these new formats.

https://bugzilla.gnome.org/show_bug.cgi?id=660188

edit: dropped the X101010 formats but also added 1010102 formats since
Cogl avoids exposing any padded formats and leaves it to applications to
consider the A component to be padding as needed. -- Robert Bragg

Reviewed-by: Robert Bragg <robert@linux.intel.com>
Reviewed-by: Neil Roberts <neil@linux.intel.com>
2012-02-20 23:12:45 +00:00
Robert Bragg
07e972505c Adds _cogl_pixel_format_is_endian_dependant api
This adds an internal utility function
_cogl_pixel_format_is_endian_dependant() that can query whether
accessing the components of a given format depends on the endianness of
the current host CPU or whether a pixel can be loaded as a word and
channels accessed using bit masking and shifting.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
2012-02-20 23:12:44 +00:00
Robert Bragg
fbec2a5ad7 moves and renames _cogl_get_format_bpp
This moves _cogl_get_format_bpp from cogl-bitmap.c to cogl.c and renames
it to _cogl_pixel_format_get_bytes_per_pixel. This makes it clearer that
it doesn't return bits per pixel and makes the naming consistent with
other cogl api. The prototype has been moved to cogl-private.h since it
seems we should be aiming to get rid of cogl-internal.h at some point.

The patch also adds a simple gtk-doc comment since we might want to make
this api public.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
2012-02-20 23:12:44 +00:00
Robert Bragg
ee940a3d0d Move all types/prototypes from cogl.h -> cogl[1]-context.h
So we can get to the point where cogl.h is merely an aggregation of
header includes for the 1.x api this moves all the function prototypes
and type definitions into a cogl-context.h and a new cogl1-context.h.

Ideally no code internally should ever need to include cogl.h as it just
represents the public facing header for accessing the 1.x api which
should only be used by Clutter.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
2012-02-20 23:12:44 +00:00
Robert Bragg
7283e0a49c rework enabling of attributes, removing _cogl_enable()
This removes the limited caching of enabled attributes done by
_cogl_enable() and replaces it with a more generalized set of bitmasks
associated with the context that allow us to efficiently compare the set
of attribute locations that are currently enabled vs the new locations
that need enabling so we only have to inform OpenGL of the changes in
which locations are enabled/disabled.

This also adds a per-context hash table for mapping attribute names to
global name-state structs which includes a unique name-index for any
name as well as pre-validated information about builtin "cogl_"
attribute names including whether the attribute is normalized and what
texture unit a texture attribute corresponds too.

The name-state hash table means that cogl_attribute_new() now only needs
to validate names the first time they are seen.

CoglAttributes now reference a name-state structure instead of just the
attribute name, so now we can efficiently get the name-index for any
attribute and we can use that to index into a per-glsl-program cache
that maps name indices to real GL attribute locations so when we get
asked to draw a set of attributes we can very quickly determine what GL
attributes need to be setup and enabled. If we don't have a cached
location though we can still quickly access the string name so we can
query OpenGL.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
2011-12-06 18:51:57 +00:00
Robert Bragg
042dc7c8cd framebuffer: Optimize _cogl_framebuffer_flush_state()
Previously the cost of _cogl_framebuffer_state_flush() would always
scale by the total amount of state tracked by CoglFramebuffer even in
cases where we knew up-front that we only wanted to flush a subset of
the state or in cases where we requested to flush the same framebuffer
multiple times with no changes being made to the framebuffer.

We now track a set of state changed flags with each framebuffer and
track the current read/draw buffers as part of the CoglContext so that
we can quickly bail out when asked to flush the same framebuffer
multiple times with no changes.

_cogl_framebuffer_flush_state() now takes a mask of the state that we
want to flush and the implementation has been redesigned so that the
cost of checking what needs to be flushed and flushing those changes
now scales by how much state we actually plan to update.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
2011-12-06 18:51:57 +00:00
Robert Bragg
ccde191191 framebuffer: Add CoglFramebuffer matrix stack methods
This adds cogl_framebuffer_ methods to update the modelview and
projection matrix stacks to replace functions like cogl_translate(),
cogl_rotate() and cogl_scale() etc.

This is part of the on-going effort to get rid of the global CoglContext
pointer since the existing methods don't take an explicit pointer to a
CoglContext. All the methods are now related to a context via the
framebuffer.

We added framebuffer methods instead of direct context methods because
the matrix stacks are per-framebuffer and as well as removing the global
CoglContext we would rather aim for a more direct state access API
design than, say, cairo or OpenGL, so we'd like to avoid needing the
cogl_push/pop_framebuffer(). We anticipate that Cogl will mostly be
consumed by middleware graphics layers such as toolkits or game engines
and feel that a more stateless model will avoid impedance mismatches if
higher levels want to expose a stateless model to their developers and
statefullness can still be added by higher levels if really desired.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
2011-12-06 18:51:56 +00:00
Robert Bragg
b72f255c0a Start to reduce dependence on glib
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>
2011-11-01 12:03:02 +00:00
Robert Bragg
426c8b8f41 features: Support more than 32 features!
Currently features are represented as bits in a 32bit mask so we
obviously can't have more than 32 features with that approach. The new
approach is to use the COGL_FLAGS_ macros which lets us handle bitmasks
without a size limit and we change the public api to accept individual
feature enums instead of a mask. This way there is no limit on the
number of features we can add to Cogl.

Instead of using cogl_features_available() there is a new
cogl_has_feature() function and for checking multiple features there is
cogl_has_features() which takes a zero terminated vararg list of
features.

In addition to being able to check for individual features this also
adds a way to query all the features currently available via
cogl_foreach_feature() which will call a callback for each feature.

Since the new functions take an explicit context pointer there is also
no longer any ambiguity over when users can first start to query
features.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
2011-11-01 12:03:01 +00:00
Robert Bragg
4c3dadd35e Add a strong CoglTexture type to replace CoglHandle
As part of the on going, incremental effort to purge the non type safe
CoglHandle type from the Cogl API this patch tackles most of the
CoglHandle uses relating to textures.

We'd postponed making this change for quite a while because we wanted to
have a clearer understanding of how we wanted to evolve the texture APIs
towards Cogl 2.0 before exposing type safety here which would be
difficult to change later since it would imply breaking APIs.

The basic idea that we are steering towards now is that CoglTexture
can be considered to be the most primitive interface we have for any
object representing a texture. The texture interface would provide
roughly these methods:

  cogl_texture_get_width
  cogl_texture_get_height
  cogl_texture_can_repeat
  cogl_texture_can_mipmap
  cogl_texture_generate_mipmap;
  cogl_texture_get_format
  cogl_texture_set_region
  cogl_texture_get_region

Besides the texture interface we will then start to expose types
corresponding to specific texture types: CoglTexture2D,
CoglTexture3D, CoglTexture2DSliced, CoglSubTexture, CoglAtlasTexture and
CoglTexturePixmapX11.

We will then also expose an interface for the high-level texture types
we have (such as CoglTexture2DSlice, CoglSubTexture and
CoglAtlasTexture) called CoglMetaTexture. CoglMetaTexture is an
additional interface that lets you iterate a virtual region of a meta
texture and get mappings of primitive textures to sub-regions of that
virtual region. Internally we already have this kind of abstraction for
dealing with sliced texture, sub-textures and atlas textures in a
consistent way, so this will just make that abstraction public. The aim
here is to clarify that there is a difference between primitive textures
(CoglTexture2D/3D) and some of the other high-level textures, and also
enable developers to implement primitives that can support meta textures
since they can only be used with the cogl_rectangle API currently.

The thing that's not so clean-cut with this are the texture constructors
we have currently; such as cogl_texture_new_from_file which no longer
make sense when CoglTexture is considered to be an interface.  These
will basically just become convenient factory functions and it's just a
bit unusual that they are within the cogl_texture namespace.  It's worth
noting here that all the texture type APIs will also have their own type
specific constructors so these functions will only be used for the
convenience of being able to create a texture without really wanting to
know the details of what type of texture you need.  Longer term for 2.0
we may come up with replacement names for these factory functions or the
other thing we are considering is designing some asynchronous factory
functions instead since it's so often detrimental to application
performance to be blocked waiting for a texture to be uploaded to the
GPU.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
2011-09-21 15:27:03 +01:00
Neil Roberts
dbff3a357e Make backface culling be part of the legacy state
This adds an internal function to set the backface culling state on a
pipeline. This includes properties to set the culling mode (front,
back or both) and also to set which face is considered the front
(COGL_WINDING_CLOCKWISE or COGL_WINDING_COUNTER_CLOCKWISE). The actual
front face flushed to GL depends on whether we are rendering to an
offscreen buffer or not. This means that when changing between on- and
off- screen framebuffers it now checks whether the last flushed
pipeline has backface culling enabled and forces a reflush of the cull
face state if so.

The backface culling is now set on a pipeline as part of the legacy
state. This is important because some code in Cogl assumes it can
flush a temporary pipeline to revert to a known state, but previously
this wouldn't disable backface culling so things such as flushing the
clip stack could get confused.

Reviewed-by: Robert Bragg <robert@linux.intel.com>
2011-09-19 16:40:07 +01:00
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
Neil Roberts
c7969a33af cogl: Bind the locale dir for the Cogl domain
dgettext (which Cogl is using) doesn't work unless you first tell
gettext where the locale dir is for the library's domain. This just
adds the necessary calls into _cogl_init.

https://bugzilla.gnome.org/show_bug.cgi?id=658700

Reviewed-by: Robert Bragg <robert@linux.intel.com>
2011-09-19 12:53:58 +01:00
Robert Bragg
a3ad808f57 framebuffer: Make framebuffer_clear APIs public experimental
This makes cogl_framebuffer_clear and cogl_framebuffer_clear4f public as
experimental API. Since these functions take explicit framebuffer
pointers you don't need to push/pop a framebuffer just to clear it. Also
these functions are implicitly tied to a specific CoglContext via the
framebuffer pointer unlike cogl_clear.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
2011-08-12 15:28:43 +01:00
Robert Bragg
2ac4002084 cogl: Add support for reading a cogl.conf config file
When cogl initializes we now check for a cogl/cogl.conf in any of the
system config dirs (determined using $XDG_CONFIG_DIRS on linux) we then
also check the user's config directory (determined using XDG_CONFIG_HOME
on linux) for a cogl/cogl.conf file. Options specified in the user
config file have priority over the system config options.

The config file has an .ini style syntax with a mandatory [global]
section and we currently understand 3 keynames: COGL_DEBUG, COGL_DRIVER
and COGL_RENDERER which have the same semantics as the corresponding
environment variables.

Options set using the environment variables have priority over options
set in the config files. To allow users to undo the enabling of debug
options in config files this patch also adds a check for COGL_NO_DEBUG
environment variable which will disable the specified options which may
have been enabled in config files.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
2011-08-12 15:28:42 +01:00
Robert Bragg
89fd2edeb0 Flush the journal before changing the projection
Since the projection matrix isn't tracked in the journal and since our
software transform of vertices as we log into the journal doesn't
include the projective transform we need to make sure we flush all
primitives in the journal before ever changing the projection.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
2011-08-02 12:05:37 +01:00
Neil Roberts
d259a87602 Don't use the 'NULL' GModule to resolve GL symbols
Previously, _cogl_get_proc_address had a fallback to resolve the
symbol using g_module_open(NULL) to get the symbol from anywhere in
the address space. The EGL backend ends up using this on some drivers
because eglGetProcAddress isn't meant to return a pointer for core
functions. This causes problems if something in the process is linking
against a different GL library, for example Cairo may be linking
against libGL itself. In this case it may end up resolving symbols
from the GL library even if GLES is being used.

This patch removes the fallback. The EGL version now has its own
fallback instead which passes the existing libgl_module from the
renderer to g_module_symbol so that it should only get symbols from
that library or its dependency chain. The GLX and WGL winsys only call
glXGetProcAddress and wglGetProcAddress. The stub winsys does however
continue using the global symbol lookup.

The internal _cogl_get_proc_address function has been renamed to
_cogl_renderer_get_proc_address because it needs a connected renderer
to work so it could be considered to be a renderer method. The pointer
to the renderer is passed down to the winsys backends so that it can
use the data attached to the renderer to get the module pointers.

https://bugzilla.gnome.org/show_bug.cgi?id=655412

Reviewed-by: Robert Bragg <robert@linux.intel.com>
2011-07-27 16:10:02 +01:00
Robert Bragg
6f79eb8a5a Use MESA_pack_invert to avoid read_pixels flip
cogl_read_pixels returns image data in a top-down memory order, but
because OpenGL normally returns pixel data in a bottom-up order we
have to flip the data before returning it to the user. If the OpenGL
driver supports the GL_MESA_pack_invert extension though we can ask the
driver to return the data in a top-down order in the first place.

Signed-off-by: Neil Roberts <neil@linux.intel.com>
2011-07-13 19:06:19 +01:00
Neil Roberts
b2e735ff7f Dynamically load the GL or GLES library
The GL or GLES library is now dynamically loaded by the CoglRenderer
so that it can choose between GL, GLES1 and GLES2 at runtime. The
library is loaded by the renderer because it needs to be done before
calling eglInitialize. There is a new environment variable called
COGL_DRIVER to choose between gl, gles1 or gles2.

The #ifdefs for HAVE_COGL_GL, HAVE_COGL_GLES and HAVE_COGL_GLES2 have
been changed so that they don't assume the ifdefs are mutually
exclusive. They haven't been removed entirely so that it's possible to
compile the GLES backends without the the enums from the GL headers.

When using GLX the winsys additionally dynamically loads libGL because
that also contains the GLX API. It can't be linked in directly because
that would probably conflict with the GLES API if the EGL is
selected. When compiling with EGL support the library links directly
to libEGL because it doesn't contain any GL API so it shouldn't have
any conflicts.

When building for WGL or OSX Cogl still directly links against the GL
API so there is a #define in config.h so that Cogl won't try to dlopen
the library.

Cogl-pango previously had a #ifdef to detect when the GL backend is
used so that it can sneakily pass GL_QUADS to
cogl_vertex_buffer_draw. This is now changed so that it queries the
CoglContext for the backend. However to get this to work Cogl now
needs to export the _cogl_context_get_default symbol and cogl-pango
needs some extra -I flags to so that it can include
cogl-context-private.h
2011-07-11 12:57:38 +01:00
Neil Roberts
5f181973a6 Move the cogl texture driver functions to a vtable
The texture driver functions are now accessed through a vtable pointed
to by a struct in the CoglContext so that eventually it will be
possible to compile both the GL and GLES texture drivers into a single
binary and then select between them at runtime.
2011-07-08 15:35:51 +01:00
Neil Roberts
2b119b07da Use all core GL functions through indirect pointers
cogl-ext-functions.h now contains definitions for all of the core GL
and GLES functions that we would normally link to directly. All of the
code has changed to access them through the cogl context pointer. The
GE macro now takes an extra parameter to specify the context because
the macro itself needs to make GL calls but various points in the Cogl
source use different names for the context variable.
2011-07-08 15:35:46 +01:00
Robert Bragg
dcb033489e framebuffer: Add _get_XYZ_bits() functions
This exposes the previously internal only
_cogl_framebuffer_get_red/green/blue/alpha_bits() functions as 2.0
experimental API.

Signed-off-by: Neil Roberts <neil@linux.intel.com>
2011-07-04 15:31:50 +01:00
Robert Bragg
c4eb869bd7 framebuffer: expose viewport getters/setters
This exposes experimental cogl_framebuffer APIs for getting and setting
a viewport without having to refer to the implicit CoglContext. It adds
the following experimental API:

  cogl_framebuffer_set_viewport
  cogl_framebuffer_get_viewport4fv
  cogl_framebuffer_get_viewport_x
  cogl_framebuffer_get_viewport_y
  cogl_framebuffer_get_viewport_width
  cogl_framebuffer_get_viewport_height

Signed-off-by: Neil Roberts <neil@linux.intel.com>
2011-06-30 14:33:11 +01:00
Robert Bragg
a1234ee8d1 Add internal _cogl_init() function
This adds a _cogl_init function for Cogl that we expect to be the first
thing called before anything else is done with Cogl. It's not a public
API so it's expected that all entry points for Cogl that might be the
first function used should call _cogl_init().

We currently call _cogl_init() in these functions:
  cogl_renderer_new
  cogl_display_new
  cogl_context_new
  cogl_android_set_native_window

_cogl_init() can be called multiple times, and only the first call has
any affect.

For example _cogl_init() gives us a place check and parse the COGL_DEBUG
environment variable.

Since we don't have any need to parse command line arguments (we can
always get user configuration options from the environment) our init
function doesn't require argc/argv pointers.

By saying up front that we aren't interested in command line arguments
that means we can avoid the mess that is GOption based library
initialization which is extremely fragile due to its lack of dependency
tracking between modules.

Signed-off-by: Neil Roberts <neil@linux.intel.com>
2011-06-30 14:33:11 +01:00
Robert Bragg
be15bf75e4 Add internal _cogl_get_proc_address
This adds an internal _cogl_get_proc_address that doesn't need a
CoglContext. This will enable us to check driver features earlier.
2011-06-01 20:44:41 +01:00
Robert Bragg
b380fed23d Make stub winsys into a proper winsys backend
Instead of the stub winsys being a special case set of #ifdef'd code
used when COGL_HAS_FULL_WINSYS wasn't defined, the stub winsys now
implements a CoglWinsysVtable like all other winsys backends (it's just
that everything is a NOP). This way we can get rid of the
COGL_HAS_FULL_WINSYS define and also the stub winsys can be runtime
selected whereas before it was incompatible with all other winsys
backends.
2011-06-01 20:44:41 +01:00
Robert Bragg
ce2da79440 Don't reference GL_STACK_OVERFLOW/UNDERFLOW for GLES
These symbols aren't available when building with GLES so only reference
them when building with OpenGL.
2011-05-05 14:46:02 +01:00
Robert Bragg
dc7383b714 Add a vtable of indirection to the winsys code
So that we can dynamically select what winsys backend to use at runtime
we need to have some indirection to how code accesses the winsys instead
of simply calling _cogl_winsys* functions that would collide if we
wanted to compile more than one backend into Cogl.
2011-05-05 14:46:01 +01:00
Robert Bragg
2bbb0d895b Make cogl_framebuffer_get_width/height experimental public API
It's generally useful to be able to query the width and height of a
framebuffer and we expect to need this in Clutter when we move the
eglnative backend code into Cogl since Clutter will need to read back
the fixed size of the framebuffer when realizing the stage.
2011-04-11 17:54:36 +01:00
Robert Bragg
d40cdfa3e1 Moves all GLX code down from Clutter to Cogl
This migrates all the GLX window system code down from the Clutter
backend code into a Cogl winsys. Moving OpenGL window system binding
code down from Clutter into Cogl is the biggest blocker to having Cogl
become a standalone 3D graphics library, so this is an important step in
that direction.
2011-04-11 17:54:36 +01:00
Robert Bragg
0b45110302 framebuffer: expose experimental cogl_get_draw_framebuffer
This renames the two internal functions _cogl_get_draw/read_buffer
as cogl_get_draw_framebuffer and _cogl_get_read_framebuffer. The
former is now also exposed as experimental API.
2011-04-11 15:28:53 +01:00
Robert Bragg
7fc6613fe9 Remove unused _cogl_swap_buffers_notify
Recently _cogl_swap_buffers_notify was added (in 142b229c5c) so that
Cogl would be notified when Clutter performs a swap buffers request for
a given onscreen framebuffer. It was expected this would be required for
the recent cogl_read_pixel optimization that was implemented (ref
1bdb0e6e98) but in the end it wasn't used.

Since it wasn't used in the end this patch removes the API.
2011-04-11 15:26:25 +01:00
Robert Bragg
fdbc741770 cogl: rename cogl-context.h cogl-context-private.h
Since we plan to add public cogl_context_* API we need to rename the
current cogl-context.h which contains private member details.
2011-04-11 15:18:12 +01:00
Robert Bragg
bc372d2734 viewport: consistently use floats for viewports
OpenGL < 4.0 only supports integer based viewports and internally we
have a mixture of code using floats and integers for viewports. This
patch switches all viewports throughout clutter and cogl to be
represented using floats considering that in the future we may want to
take advantage of floating point viewports with modern hardware/drivers.
2011-03-07 13:26:19 +00:00
Neil Roberts
a067e7a16b cogl-framebuffer: Separate the draw and read buffer
The current framebuffer is now internally separated so that there can
be a different draw and read buffer. This is required to use the
GL_EXT_framebuffer_blit extension. The current draw and read buffers
are stored as a pair in a single stack so that pushing the draw and
read buffer is done simultaneously with the new
_cogl_push_framebuffers internal function. Calling
cogl_pop_framebuffer will restore both the draw and read buffer to the
previous state. The public cogl_push_framebuffer function is layered
on top of the new function so that it just pushes the same buffer for
both drawing and reading.

When flushing the framebuffer state, the cogl_framebuffer_flush_state
function now tackes a pointer to both the draw and the read
buffer. Anywhere that was just flushing the state for the current
framebuffer with _cogl_get_framebuffer now needs to call both
_cogl_get_draw_buffer and _cogl_get_read_buffer.
2011-02-15 12:10:54 +00:00