Commit Graph

136 Commits

Author SHA1 Message Date
Robert Bragg
d1353b3c1a cogl: renames cogl_multiply_matrix to cogl_transform
Although cogl_multiply_matrix was consistent with OpenGL, after further
consideration it was agreed that cogl_transform is a better name. Given
that it's in the global cogl_ namespace cogl_transform seems more self
documenting.
2010-04-08 14:37:01 +01:00
Robert Bragg
c49aeed2bf cogl: move cogl_set_source* funcs into cogl.c
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.
2010-04-06 09:26:05 +01:00
Robert Bragg
6c8c0714f6 cogl: adds convenience cogl_multiply_matrix function
Quite often it's desirable to be able to multiply the current modelview
matrix by an arbitrary matrix. Currently though you have to first
explicitly call cogl_get_modelview_matrix to get the current modelview
into a temporary variable, then you need to multiply it with your matrix
using cogl_matrix_multiply and finally use cogl_set_modelview_matrix to
make the result be the new modelview. This new convenience function lets
more efficiently skip the first get and last set steps.
2010-04-01 13:24:56 +01:00
Robert Bragg
1f715ad153 cogl: rename cogl_enable to _cogl_enable
Every now and then someone sees the cogl_enable API and gets confused,
thinking its public API so this renames the symbol to be clear that it's
is an internal only API.
2010-04-01 12:34:42 +01:00
Neil Roberts
84223c855d cogl: Support any format in cogl_read_pixels
cogl_read_pixels() no longer asserts that the format passed in is
RGBA_8888 but instead accepts any format. The appropriate GL enums for
the format are passed to glReadPixels so OpenGL should be perform a
conversion if neccessary.

It currently assumes glReadPixels will always give us premultiplied
data. This will usually be correct because the result of the default
blending operations for Cogl ends up with premultiplied data in the
framebuffer. However it is possible for the framebuffer to be in
whatever format depending on what CoglMaterial is used to render to
it. Eventually we may want to add a way for an application to inform
Cogl that the framebuffer is not premultiplied in case it is being
used for some special purpose.

If the requested format is not premultiplied then Cogl will convert
it. The tests have been changed to read the data as premultiplied so
that they won't be affected by the conversion. Picking in Clutter has
been changed to use COGL_PIXEL_FORMAT_RGB_888 because it doesn't need
the alpha component. clutter_stage_read_pixels is left unchanged
because the application can't specify a format for that so it seems to
make most sense to store unpremultiplied values.

http://bugzilla.openedhand.com/show_bug.cgi?id=1959
2010-03-02 11:01:35 +00:00
Emmanuele Bassi
72f4ddf532 Remove mentions of the FSF address
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
2010-03-01 12:56:10 +00:00
Robert Bragg
5751e48756 cogl debug: hint that all debugging paths are G_UNLIKELY
Most Cogl debugging code conditions are marked as G_UNLIKELY with the
intention of having the CPU branch prediction always assume the
path is disabled so having debugging support in release binaries has
negligible overhead.

This patch simply fixes a few cases where we weren't using G_UNLIKELY.
2010-02-23 22:09:07 +00:00
Neil Roberts
fbe9e80a07 cogl: Cache the value for GL_MAX_TEXTURE_UNITS
The function _cogl_get_max_texture_units is called quite often while
rendering and it returns a constant value so we might as well cache
the result. Calling glGetInteger on Mesa can be expensive because it
flushes a lot of state.
2010-02-12 14:38:53 +00:00
Robert Bragg
0f5f4e8645 cogl: improves header and coding style consistency
We've had complaints that our Cogl code/headers are a bit "special" so
this is a first pass at tidying things up by giving them some
consistency. These changes are all consistent with how new code in Cogl
is being written, but the style isn't consistently applied across all
code yet.

There are two parts to this patch; but since each one required a large
amount of effort to maintain tidy indenting it made sense to combine the
changes to reduce the time spent re indenting the same lines.

The first change is to use a consistent style for declaring function
prototypes in headers. Cogl headers now consistently use this style for
prototypes:

 return_type
 cogl_function_name (CoglType arg0,
                     CoglType arg1);

Not everyone likes this style, but it seems that most of the currently
active Cogl developers agree on it.

The second change is to constrain the use of redundant glib data types
in Cogl. Uses of gint, guint, gfloat, glong, gulong and gchar have all
been replaced with int, unsigned int, float, long, unsigned long and char
respectively. When talking about pixel data; use of guchar has been
replaced with guint8, otherwise unsigned char can be used.

The glib types that we continue to use for portability are gboolean,
gint{8,16,32,64}, guint{8,16,32,64} and gsize.

The general intention is that Cogl should look palatable to the widest
range of C programmers including those outside the Gnome community so
- especially for the public API - we want to minimize the number of
foreign looking typedefs.
2010-02-12 14:05:00 +00:00
Robert Bragg
10fa7c7ce9 cogl: deprecates cogl_check_extension
OpenGL is an implementation detail for Cogl so it's not appropriate to
expose OpenGL extensions through the Cogl API.

Note: Clutter is currently still using this API, because it is still
doing raw GL calls in ClutterGLXTexturePixmap, so this introduces a
couple of (legitimate) build warnings while compiling Clutter.
2010-02-12 14:05:00 +00:00
Neil Roberts
47df6724b2 cogl: Use the colours of COGL_DEBUG=rectangles to debug batching
Instead of assigning a new colour to each quad of a batch, the
rectangle debugging code now assigns a new colour to each batch so
that it can be used to visually see what is being batched. The colour
is stored in a global variable that is reset during cogl_clear. This
improves the chances that the same colour will be used for a batch in
the next frames to avoid flickering.
2010-01-28 16:52:42 +00:00
Damien Lespiau
9d45e9641c cogl: Fix checks of the number of available texture units
We were checking the number of texture units against the GL enum that is
used in glGetInteger() to query that number. Let's abstract this in a
little function.

Took the opportunity to dig a bit on the usage of GL limits for the
number of texture (image) units and document our use of them. We'll need
something finer grained if we want to fully exploit texture image units
with a programmable pipeline.
2010-01-26 18:47:25 +00:00
Damien Lespiau
3069ad6409 cogl: Create CoglTextureUnit with its associated unit number
The index field of CoglTextureUnit was never set, leading to the
creation of units with index set to 0. When trying to retrieve a texture
unit by its index (!= 0) with _cogl_get_texture_unit(), a new one was
created as it could not find it back in the list of textures units:
ctx->texture_units.

http://bugzilla.openedhand.com/show_bug.cgi?id=1958
2010-01-26 12:12:20 +00:00
Robert Bragg
944423a8d9 cogl: deprecate cogl_draw_buffer API and replace with a cogl_framebuffer API
cogl_push_draw_buffer, cogl_set_draw_buffer and cogl_pop_draw_buffer are now
deprecated and new code should use the new cogl_framebuffer_* API instead.

Code that previously did:
    cogl_push_draw_buffer ();
    cogl_set_draw_buffer (COGL_OFFSCREEN_BUFFER, buffer);
    /* draw */
    cogl_pop_draw_buffer ();
should now be re-written as:
    cogl_push_framebuffer (buffer);
    /* draw */
    cogl_pop_framebuffer ();

As can be seen from the example above the rename has been used as an
opportunity to remove the redundant target argument from
cogl_set_draw_buffer; it now only takes one call to redirect to an offscreen
buffer, and finally the term framebuffer may be a bit more familiar to
anyone coming from an OpenGL background.
2009-11-26 19:33:14 +00:00
Robert Bragg
16a09763ef [cogl-material] Adds cogl_material_copy() API
cogl_material_copy can be used to create a new CoglHandle referencing a copy
of some given material.

From now on we will advise that developers always aim to use this function
instead of cogl_material_new() when creating a material that is in any way
derived from another.

By using cogl_material_copy, Cogl can maintain an ancestry for each material
and keep track of "similar" materials.  The plan is that Cogl will use this
information to minimize the cost of GPU state transitions.
2009-11-24 17:58:22 +00:00
Robert Bragg
d2ce4f7137 docs: Don't document cogl_flush_gl_state as public API
This function was #if 0'd before we released Clutter 1.0 so there's no
implementation of it.  At some point we thought it might assist with
developers breaking out into raw OpenGL.  Breaking out to raw GL is a
difficult problem though so we decided instead we will wait for a specific
use case to arrise before trying to support it.
2009-11-24 17:58:22 +00:00
Neil Roberts
a50907848f Validate that the GL version is >= 1.2
There is a new internal Cogl function called _cogl_check_driver_valid
which looks at the value of the GL_VERSION string to determine whether
the driver is supported. Clutter now calls this after the stage is
realized. If it fails then the stage is marked as unrealized and a
warning is shown.

_cogl_features_init now also checks the version number before getting
the function pointers for glBlendFuncSeparate and
glBlendEquationSeparate. It is not safe to just check for the presence
of the functions because some drivers may define the function without
fully implementing the spec.

The GLES version of _cogl_check_driver_valid just always returns TRUE
because there are no version requirements yet.

Eventually the function could also check for mandatory extensions if
there were any.

http://bugzilla.openedhand.com/show_bug.cgi?id=1875
2009-11-13 15:55:48 +00:00
Neil Roberts
6c5110cb4b cogl: Add an initialiser for enable_flags in cogl_begin_gl
This fixes a warning about an uninitialised value. It could also
potentially fix some crashes for example if the enable_flags value
happened to include a bit for enabling a vertex array if no vertex
buffer pointer was set.
2009-11-09 11:50:16 +00:00
Emmanuele Bassi
339b447075 Do not pass flags to g_module_open(NULL)
The flags are ignored when opening the main module, so we
should pass 0 to avoid confusion when reading the source.
2009-11-06 14:06:18 +00:00
Robert Bragg
6ca49145f4 [clip-stack] move lots of supporting code from cogl.c to cogl-clip-stack.c
There was quite a bit of code in cogl.c that was only used to support
cogl-clip-stack.c, so this has now been moved to cogl-clip-stack.c
2009-11-05 21:10:16 +00:00
Robert Bragg
28c7e940bf [matrix] Adds cogl_matrix_get_inverse API
This new API takes advantage of the recently imported Mesa code to support
inverse matrix calculation.  The matrix code keeps track (via internal
flags) of the transformations a matrix represents so that it can select an
optimized inversion function.

Note: although other aspects of the Cogl matrix API have followed a similar
style to Cairo's matrix API we haven't added a cogl_matrix_invert API
because the inverse of a CoglMatrix is actually cached as part of the
CoglMatrix structure meaning a destructive API like cogl_matrix_invert
doesn't let users take advantage of this caching design.
2009-11-04 03:34:05 +00:00
Robert Bragg
2126bf60fd [debug] Adds a COGL_DEBUG=matrices debug option
This adds a COGL_DEBUG=matrices debug option that can be used to trace all
matrix manipulation done using the Cogl API.  This can be handy when you
break something in such a way that a trace is still comparable with a
previous working version since you can simply diff a log of the broken
version vs the working version to home in on the bug.
2009-11-04 03:34:04 +00:00
Robert Bragg
8ca17f5262 [cogl] avoid any state changes when cogl_set_backface_culling_enable is a nop
This is a simple optimization to bail out of cogl_set_backface_culling_enable
if it's not resulting in a change of state.
2009-11-04 03:34:04 +00:00
Robert Bragg
181bf92086 [cogl] Use clockwise face winding for offscreen buffers with culling enabled
Because Cogl defines the origin for texture as top left and offscreen draw
buffers can be used to render to textures, we (internally) force all
offscreen rendering to be upside down. (because OpenGL defines the origin
to be bottom left)

By forcing the users scene to be rendered upside down though we also reverse
the winding order of all the drawn triangles which may interfere with the
users use of backface culling.  This patch ensures that we reverse the
winding order for a front face (if culling is in use) while rendering
offscreen so we don't conflict with the users back face culling.
2009-11-04 03:34:03 +00:00
Robert Bragg
1acf5cc36f [cogl_read_pixels] don't force a 4 byte pack alignment
Technically this change shouldn't make a difference since we are
calling glReadPixels with GL_RGBA GL_UNSIGNED_BYTE which is a 4
byte format and it should always result in the same value according
to how OpenGL calculates the location of sequential rows.

i.e. k  = a/s * ceil(snl/a) where:
 a = alignment
 s = component size (1)
 n = number of components per pixel (4)
 l = number of pixels in a row
gives:
k = 4/1 * ceil(4l/4) and k = 1/1 * ceil(4l/1) which are equivalent

I'm changing it because I've seen i915 driver code that bails out of
hardware accelerated paths if the alignment isn't 1, and because
conceptually we have no alignment constraints here so even if the current
value has no effect, when we start reading back other formats it may upset
things.
2009-11-04 03:34:03 +00:00
Robert Bragg
f59180d073 [cogl_read_pixels] call cogl_flush() before changing glPixelStore state
We were previously calling cogl_flush() after setting up the glPixelStore
state for calling glReadPixels, but flushing the journal could itself
change the glPixelStore state.
2009-11-04 03:34:02 +00:00
Robert Bragg
d1de286109 [cogl_read_pixels] ensure we flush the current draw buffer state before reading
Make sure we call _cogl_draw_buffer_flush_state() before glReadPixels() to
be sure we have bound the correct framebuffer.
2009-11-04 03:34:02 +00:00
Robert Bragg
b8fe310b6d [cogl_read_pixels] fixes for calculating the y offset when rendering offscreen
Since offscreen rendering is forced to be upside down we don't need to do
any conversion of the users coordinates to go from Cogl window coordinates
to OpenGL window coordinates.
2009-11-04 03:34:02 +00:00
Robert Bragg
800d18bc19 [read-pixels] don't flip data when reading from offscreen draw buffers
Since we do all offscreen rendering upside down (so that we can have the
origin for texture coordinates be the top left of textures for the cases
where offscreen draw buffers are bound to textures) we don't need to flip
data read back from an offscreen framebuffer before we we return it to the
user.
2009-11-04 03:34:01 +00:00
Robert Bragg
78ee3f71b2 [cogl] deprecate cogl_viewport() in favour of cogl_set_viewport()
cogl_viewport only accepted a viewport width and height, but there are times
when it's also desireable to have a viewport offset so that a scene can be
translated after projection but before hitting the framebuffer.
2009-11-04 03:23:21 +00:00
Robert Bragg
c2a982cf9c [cogl_read_pixels] use buffer not viewport height to calculate y offset
glReadPixel takes window coordinates not viewport coordinates so we
shouldn't have been assuming that the viewport height == window height.
2009-11-04 03:23:20 +00:00
Robert Bragg
bb3a008318 [draw-buffers] First pass at overhauling Cogl's framebuffer management
Cogl's support for offscreen rendering was originally written just to support
the clutter_texture_new_from_actor API and due to lack of documentation and
several confusing - non orthogonal - side effects of using the API it wasn't
really possible to use directly.

This commit does a number of things:
- It removes {gl,gles}/cogl-fbo.{c,h} and adds shared cogl-draw-buffer.{c,h}
  files instead which should be easier to maintain.
- internally CoglFbo objects are now called CoglDrawBuffers. A
  CoglDrawBuffer is an abstract base class that is inherited from to
  implement CoglOnscreen and CoglOffscreen draw buffers.  CoglOffscreen draw
  buffers will initially be used to support the
  cogl_offscreen_new_to_texture API, and CoglOnscreen draw buffers will
  start to be used internally to represent windows as we aim to migrate some
  of Clutter's backend code to Cogl.
- It makes draw buffer objects the owners of the following state:
  - viewport
  - projection matrix stack
  - modelview matrix stack
  - clip state
(This means when you switch between draw buffers you will automatically be
 switching to their associated viewport, matrix and clip state)

Aside from hopefully making cogl_offscreen_new_to_texture be more useful
short term by having simpler and well defined semantics for
cogl_set_draw_buffer, as mentioned above this is the first step for a couple
of other things:
- Its a step toward moving ownership for windows down from Clutter backends
  into Cogl, by (internally at least) introducing the CoglOnscreen draw
  buffer.  Note: the plan is that cogl_set_draw_buffer will accept on or
  offscreen draw buffer handles, and the "target" argument will become
  redundant since we will instead query the type of the given draw buffer
  handle.
- Because we have a common type for on and offscreen framebuffers we can
  provide a unified API for framebuffer management. Things like:
  - blitting between buffers
  - managing ancillary buffers (e.g. attaching depth and stencil buffers)
  - size requisition
  - clearing
2009-11-03 17:23:03 +00:00
Emmanuele Bassi
be06fe0b75 cogl: Avoid C99-isms
Do not declare variables after statements.
2009-10-23 16:44:28 +01:00
Robert Bragg
eed2479556 [cogl] Removes the cogl-current-matrix abstraction
The indirection through this API isn't necessary since we no longer
arbitrate between the OpenGL matrix API and Cogl's client side API.  Also it
doesn't help to maintain an OpenGL style matrix mode API for internal use
since it's awkward to keep restoring the MODELVIEW mode and easy enough to
directly work with the matrix stacks of interest.

This replaces use of the _cogl_current_matrix API with direct use of the
_cogl_matrix_stack API.  All the unused cogl_current_matrix API is removed
and the matrix utility code left in cogl-current-matrix.c was moved to
cogl.c.
2009-10-20 12:32:50 +01:00
Robert Bragg
1402d1eb3c [current-matrix] Adds texture matrix stacks + removes GL matrix API usage
This relates back to an earlier commitment to stop using the OpenGL matrix
API which is considered deprecated. (ref 54159f5a1d)

The new texture matrix stacks are hung from a list of (internal only)
CoglTextureUnit structures which the CoglMaterial code internally references
via _cogl_get_texure_unit ().

So we would be left with only the cogl-matrix-stack code being responsible
for glMatrixMode, glLoadMatrix and glLoadIdentity this commit updates the
journal code so it now uses the matrix-stack API instead of GL directly.
2009-10-20 12:32:45 +01:00
Robert Bragg
0bce7eac53 Intial Re-layout of the Cogl source code and introduction of a Cogl Winsys
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.
2009-10-16 18:58:50 +01:00