Commit Graph

22 Commits

Author SHA1 Message Date
Ole André Vadla Ravnås
237553984e Call glClientActiveTexture() through COGL context.
Fixes build issues on systems with OpenGL header older than 1.3.
2009-07-28 12:13:43 +01:00
Ole André Vadla Ravnås
243b22640d Avoid C99 to fix compilation with compilers like MSVC. 2009-07-28 12:13:43 +01:00
Robert Bragg
fffcf579d5 [cogl matrix stack] Create a client side matrix stack for the projection matrix
The cost of glGetFloatv with Mesa is still representing a majority of our
time in OpenGL for some applications, and the last thing left using this is
the current-matrix API when getting the projection matrix.

This adds a matrix stack for the projection matrix, so all getting, setting
and modification of the projection matrix is now managed by Cogl and it's only
when we come to draw that we flush changes to the matrix to OpenGL.

This also brings us closer to being able to drop internal use of the
deprecated OpenGL matrix functions, re: commit 54159f5a1d
2009-07-07 10:32:56 +01:00
Emmanuele Bassi
a6880643a0 Add debug notes for calls to glViewport()
In order to validate the sequence of:

        XResizeWindow
        ConfigureNotify
        glViewport

that should happen on X11 we need to add debug annotations to the
calls to glViewport() done through COGL.
2009-07-01 15:30:18 +01:00
Robert Bragg
82ef6b51b9 [cogl] cache the viewport width and height
This avoids some calls to glGetFloatv, which have at least proven to be very
in-efficient in mesa at this point in time, since it always updates all derived
state even when it may not relate to the state being requested.
2009-07-01 15:23:10 +01:00
Robert Bragg
b4bc9eb458 [cogl] Improve ability to break out into raw OpenGL via begin/end mechanism
Although we wouldn't recommend developers try and interleve OpenGL drawing
with Cogl drawing - we would prefer patches that improve Cogl to avoid this
if possible - we are providing a simple mechanism that will at least give
developers a fighting chance if they find it necissary.

Note: we aren't helping developers change OpenGL state to modify the
behaviour of Cogl drawing functions - it's unlikley that can ever be
reliably supported - but if they are trying to do something like:

   - setup some OpenGL state.
   - draw using OpenGL (e.g. glDrawArrays() )
   - reset modified OpenGL state.
   - continue using Cogl to draw

They should surround their blocks of raw OpenGL with cogl_begin_gl() and
cogl_end_gl():

   cogl_begin_gl ();
   - setup some OpenGL state.
   - draw using OpenGL (e.g. glDrawArrays() )
   - reset modified OpenGL state.
   cogl_end_gl ();
   - continue using Cogl to draw

Again; we aren't supporting code like this:
   - setup some OpenGL state.
   - use Cogl to draw
   - reset modified OpenGL state.
When the internals of Cogl evolves, this is very liable to break.

cogl_begin_gl() will flush all internally batched Cogl primitives, and emit
all internal Cogl state to OpenGL as if it were going to draw something
itself.

The result is that the OpenGL modelview matrix will be setup; the state
corresponding to the current source material will be setup and other world
state such as backface culling, depth and fogging enabledness will be also
be sent to OpenGL.

Note: no special material state is flushed, so if developers want Cogl to setup
a simplified material state it is the their responsibility to set a simple
source material before calling cogl_begin_gl. E.g. by calling
cogl_set_source_color4ub().

Note: It is the developers responsibility to restore any OpenGL state that they
modify to how it was after calling cogl_begin_gl() if they don't do this then
the result of further Cogl calls is undefined.
2009-06-30 17:13:38 +01:00
Robert Bragg
99f53c3922 Adds a cogl_flush() to give developers breaking into raw GL a fighting chance
This function should only need to be called in exceptional circumstances
since Cogl can normally determine internally when a flush is necessary.

As an optimization Cogl drawing functions may batch up primitives
internally, so if you are trying to use raw GL outside of Cogl you stand a
better chance of being successful if you ask Cogl to flush any batched
geometry before making your state changes.

cogl_flush() ensures that the underlying driver is issued all the commands
necessary to draw the batched primitives.  It provides no guarantees about
when the driver will complete the rendering.

This provides no guarantees about the GL state upon returning and to avoid
confusing Cogl you should aim to restore any changes you make before
resuming use of Cogl.

If you are making state changes with the intention of affecting Cogl drawing
primitives you are 100% on your own since you stand a good chance of
conflicting with Cogl internals.  For example clutter-gst which currently
uses direct GL calls to bind ARBfp programs will very likely break when Cogl
starts to use ARBfb programs internally for the material API, but for now it
can use cogl_flush() to at least ensure that the ARBfp program isn't applied
to additional primitives.

This does not provide a robust generalized solution supporting safe use of
raw GL, its use is very much discouraged.
2009-06-30 17:13:38 +01:00
Robert Bragg
540a91c7fc [cogl] Adds a debug option for disabling use of VBOs --cogl-debug=disable-vbos
For testing the VBO fallback paths it helps to be able to disable the
COGL_FEATURE_VBOS feature flag.  When VBOs aren't available Cogl should use
client side malloc()'d buffers instead.
2009-06-30 17:13:35 +01:00
Robert Bragg
2b9478a665 [cogl] Improving Cogl journal to minimize driver overheads + GPU state changes
Previously the journal was always flushed at the end of
_cogl_rectangles_with_multitexture_coords, (i.e.  the end of any
cogl_rectangle* calls) but now we have broadened the potential for batching
geometry.  In ideal circumstances we will only flush once per scene.

In summary the journal works like this:

When you use any of the cogl_rectangle* APIs then nothing is emitted to the
GPU at this point, we just log one or more quads into the journal.  A
journal entry consists of the quad coordinates, an associated material
reference, and a modelview matrix.  Ideally the journal only gets flushed
once at the end of a scene, but in fact there are things to consider that
may cause unwanted flushing, including:

- modifying materials mid-scene
    This is because each quad in the journal has an associated material
    reference (i.e. not copy), so if you try and modify a material that is
    already referenced in the journal we force a flush first)

    NOTE: For now this means you should avoid using cogl_set_source_color()
	      since that currently uses a single shared material. Later we
	  should change it to use a pool of materials that is recycled
	  when the journal is flushed.

- modifying any state that isn't currently logged, such as depth, fog and
  backface culling enables.

The first thing that happens when flushing, is to upload all the vertex data
associated with the journal into a single VBO.

We then go through a process of splitting up the journal into batches that
have compatible state so they can be emitted to the GPU together.  This is
currently broken up into 3 levels so we can stagger the state changes:

1) we break the journal up according to changes in the number of material layers
   associated with logged quads. The number of layers in a material determines
   the stride of the associated vertices, so we have to update our vertex
   array offsets at this level. (i.e. calling gl{Vertex,Color},Pointer etc)
2) we further split batches up according to material compatability. (e.g.
   materials with different textures) We flush material state at this level.
3) Finally we split batches up according to modelview changes. At this level
   we update the modelview matrix and actually emit the actual draw command.

This commit is largely about putting the initial design in-place; this will be
followed by other changes that take advantage of the extended batching.
2009-06-30 17:13:34 +01:00
Robert Bragg
606fb8f56f [cogl] Adds cogl_read_pixels to replace direct use of glReadPixels
To allow for flushing of batched geometry within Cogl we can't support users
directly calling glReadPixels.  glReadPixels is also awkward, not least
because it returns upside down image data.

All the unit tests have been swithed over and clutter_stage_read_pixels now
sits on top of this too.
2009-06-29 23:49:06 +01:00
Owen W. Taylor
f0de41331a Default to a blend function that expects premultiplied colors
Many operations, like mixing two textures together or alpha-blending
onto a destination with alpha, are done most logically if texture data
is in premultiplied form. We also have many sources of premultiplied
texture data, like X pixmaps, FBOs, cairo surfaces. Rather than trying
to work with two different types of texture data, simplify things by
always premultiplying texture data before uploading to GL.

Because the default blend function is changed to accommodate this,
uses of pure-color CoglMaterial need to be adapted to add
premultiplication.

gl/cogl-texture.c gles/cogl-texture.c: Always premultiply
  non-premultiplied texture data before uploading to GL.

cogl-material.c cogl-material.h: Switch the default blend functions
  to ONE, ONE_MINUS_SRC_ALPHA so they work correctly with premultiplied
  data.

cogl.c: Make cogl_set_source_color() premultiply the color.

cogl.h.in color-material.h: Add some documentation about
  premultiplication and its interaction with color values.

cogl-pango-render.c clutter-texture.c tests/interactive/test-cogl-offscreen.c:
  Use premultiplied colors.

http://bugzilla.openedhand.com/show_bug.cgi?id=1406

Signed-off-by: Robert Bragg <robert@linux.intel.com>
2009-06-11 14:17:52 +01:00
Emmanuele Bassi
5ed1b03a91 [cogl] Make cogl_setup_viewport() a private function
The setup_viewport() function should only be used by Clutter and
not by application code.

It can be emulated by changing the Stage size and perspective and
requeueing a redraw after calling clutter_stage_ensure_viewport().
2009-05-28 14:14:50 +01:00
Robert Bragg
2f0bda49fc [cogl] renamed cogl_enable_* to cogl_set_*_enabled + added getters
cogl_enable_depth_test and cogl_enable_backface_culling have been renamed
and now have corresponding getters, the new functions are:
  cogl_set_depth_test_enabled
  cogl_get_depth_test_enabled
  cogl_set_backface_culling_enabled
  cogl_get_backface_culling_enabled
2009-05-28 02:43:36 +01:00
Robert Bragg
02faadae8b [cogl] Remove cogl_flush_gl_state from the API
This is being removed before we release Clutter 1.0 since the implementation
wasn't complete, and so we assume no one is using this yet.  Util we have
someone with a good usecase, we can't pretend to support breaking out into
raw OpenGL.
2009-05-28 02:43:34 +01:00
Robert Bragg
492f0e5d14 [material] Reduce the material API in preperation for releasing Clutter 1.0
There were a number of functions intended to support creating of new
primitives using materials, but at this point they aren't used outside of
Cogl so until someone has a usecase and we can get feedback on this
API, it's being removed before we release Clutter 1.0.
2009-05-28 02:43:34 +01:00
Emmanuele Bassi
cf4a49061a [cogl] Rework the debug messages
COGL has a debug message system like Clutter's own. In parallel,
it also uses a coupld of #defines. Spread around there are also
calls to printf() instead to the more correct g_log* wrappers.

This commit tries to unify and clean up the macros and the
debug message handling inside COGL to be more consistent.
2009-05-19 14:44:29 +01:00
Emmanuele Bassi
64b727d329 [cogl] Rework the GL-error-to-string conversion
The code for the conversion of the GL error enumeration code
into a string is not following the code style and conventions
we follow in Clutter and COGL.

The GE() macro is also using fprintf(stderr) directly instead
of using g_warning() -- which is redirectable to an alternative
logging system using the g_log* API.
2009-05-19 13:24:56 +01:00
Robert Bragg
aeb1516a89 [cogl-clip-stack] Support pushing rectangles onto the stack using window coords
Previously clipping could only be specified in object coordinates, now
rectangles can also be pushed in window coordinates.

Internally rectangles pushed this way are intersected and then clipped using
scissoring.  We also transparently try to convert rectangles pushed in
object coordinates into window coordinates as we anticipate the scissoring
path will be faster then the clip planes and undoubtably it will be faster
than using the stencil buffer.
2009-05-12 15:44:33 +01:00
Robert Bragg
7e9685294e [cogl] Updates all file headers and removes lots of trailing white space
Adds missing notices, and ensures all the notices are consistent. The Cogl
blurb also now reads:

 * Cogl
 *
 * An object oriented GL/GLES Abstraction/Utility Layer
2009-05-02 04:12:25 +01:00
Robert Bragg
2d94b3f46f [cogl] Adds a bitfield argument to cogl_clear for specifying which buffers to clear
Redundant clearing of depth and stencil buffers every render can be very
expensive, so cogl now gives control over which auxiliary buffers are
cleared.

Note: For now clutter continues to clear the color, depth and stencil buffer
each paint.
2009-05-02 04:12:12 +01:00
Robert Bragg
598939cee1 [gl/cogl.c] #include <gmodule.h> for OS X builds
In unifying the {gl,gles}/cogl.c code recently, moving most of the code into
common/cogl.c the gmodule.h include was also mistakenly moved.

Thanks to Felix Rabe for reporting this issue.

Note: I haven't tested this fix myself, as I'm not set up to be able to
build for OS X
2009-04-20 14:20:37 +01:00
Robert Bragg
c2afbd415e Unifies 90% of the code in {gl,gles}/cogl.c in common/cogl.c
This code keeps on diverging and we get bugs and fixes in one version but
not the other. This should make things a bit more maintainable.
2009-04-01 13:19:35 +01:00