Decided might be better to cover crossing and motion under
a broader "pointer motion" recipe, so renamed the example
(which only shows pointer crossing event handling).
It can be useful to be able to forcibly break the grab set up by the
ClickAction. The newly added release() method provides a mechanism to
release the grab and unset the :held state of the ClickAction.
Rewrote example for single texture + COGL to use
a GdkPixbuf to load images, rather than reading data
out of another CoglTexture.
The data is then loaded from the pixbuf to a region of
the CoglTexture (as before).
The recipe covers a two texture approach (using the Clutter API)
and a single texture approach (using COGL).
It also discusses issues with cross-fading between images of
different sizes with the COGL API, and gives a longer
example of cycling through multiple images in a slideshow
application.
Added a video showing the two texture cross-fade.
Modified the example code to animate on key press, so
this video could be captured.
Also altered the stage size to minimise the video size.
Front/back seems like the wrong terminology when discussing
actors arranged in layers. Top/bottom fits better with Clutter
API function names and other recipes, so renamed variables.
Cross-fading between two images is straightforward,
but cycling between more than two is more efficient
if done by copying COGL textures between the
two textures, rather than trying to reposition the
textures.
The example demonstrates how to reuse a pair of
textures to cycle through multiple images.
Modified the code example for the Clutter API version
of the cross-fade to use the same command line
as the COGL version.
This also simplifies the explanation in the recipe.
Also made the COGL code sample more consistent with
the Clutter API code sample.
Added simple image viewer which loads image file names
from a directory, displays the first one, then displays
the next in the list with each key press. Uses the
primitive fade front in/fade back out approach.
Also adapted Emmanuele's example code which uses Cogl
to produce a similar effect, but within a single texture.
This code loads two images specified on the command
line and cross-fades between them.
The tests/accessibility, tests/micro-bench and the examples directory
in the coobook create a lot of non-installed binaries. Since we know who
they are, and we ignore them, we can auto-generate the ignore files as
well.
The rest of Clutter is covered by the main ignore file.
* elliot/cookbook-events-mouse-scroll:
cookbook: Cleaning up grammar and wording in mouse scroll recipe
cookbook: Added more explanation about setting y coord on scrollable
cookbook: Mentioned the animation in the sample code
cookbook: Included video of the scroll example running
cookbook: Made stage slightly smaller for scroll event example
cookbook: Added video showing scrollable actor
cookbook: Added walk through of code example for mouse scroll
cookbook: Fixed link to example in mouse scroll recipe
cookbook: Simplified full scroll example
cookbook: Improved wording and formatting in mouse scroll intro.
cookbook: Handle all possible mouse scroll directions
cookbook: Build mouse scroll example with cookbook
cookbook: Cleaned up redundant comments in code example
cookbook: Added xmlns for XInclude to events docbook file
cookbook: Added basic mouse scroll recipe
This removes all references to SDL in the build instructions as the
backend is no longer available. The OpenGL version required is only
1.2 not 1.4. The Windows build instructions were out of date and have
been replaced with a link to the wiki instead.
Instead of exposing an API that provides an OpenGL state machine style
where you first have to bind the program to the context using
cogl_program_use() followed by updating uniforms using
cogl_program_uniform_xyz we now have uniform setter methods that take an
explicit CoglHandle for the program.
This deprecates cogl_program_use and all the cogl_program_uniform
variants and provides the following replacements:
cogl_program_set_uniform_1i
cogl_program_set_uniform_1f
cogl_program_set_uniform_int
cogl_program_set_uniform_float
cogl_program_set_uniform_matrix
Added some extra explanation, referencing the sample code, to
try to make the scrollable actor example easier to follow. Basically
demonstrates the principles described in the paragraph about
setting the y coordinate for the scrollable actor, but using actual
numbers.
A TableLayout is a layout manager that allocates its children in rows
and columns. Each child is assigned to a cell (or more if a cell span
is set).
The supported child properties are:
• x-expand and y-expand: if this cell with try to allocate the
available extra space for the table.
• x-fill and y-fill: if the child will get all the space available in
the cell.
• x-align and y-align: if the child does not fill the cell, then
where the child will be aligned inside the cell.
• row-span and col-span: number of cells the child will allocate for
itself.
Also, the TableLayout has row-spacing and col-spacing for specifying
the space in pixels between rows and between columns.
We also include a simple test of the layout manager, and the
documentation updates.
The TableLayout was implemented starting from MxTable and
ClutterBoxLayout.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2038
Signed-off-by: Emmanuele Bassi <ebassi@linux.intel.com>
Layout managers are using the same code to allocate a child while taking
into consideration:
• horizontal and vertical alignment
• horizontal and vertical fill
• the preferred minimum and natural size, depending
on the :request-mode property
• the text direction for the horizontal alignment
• an offset given by the fixed position properties
Given the amount of code involved, and the amount of details that can go
horribly wrong while copy and pasting such code in various classes - let
alone various projects - Clutter should provide an allocate() variant
that does the right thing in the right way. This way, we have a single
point of failure.
Added a new recipe for creating a non-rectangular
actor using ClutterPath (aka "shaped pick") and
the Cogl primitives API.
Also cleaned up XML alignment in the actors.xml
file.
It's a XSL FAQ to be able to chomp text nodes and we just have to copy
and paste a XSLT 1.0 solution from:
http://dpawson.co.uk/xsl/sect2/N8321.html#d11325e833
Let's then empower our cookbook customization layer to chomp text nodes,
children of programlisting.
The generated cookbook files (either HTML or PDF) do not only depend on
clutter-cookbok.xml but also on all the chapters that compose the
cookbook. Add this dependency to the Makefile rules to have make rebuild
the book when a chapter changes.
Since XML_FILES is now the list of source files, move recipe-template.xml
to EXTRA_DIST.
New recipe covering how to animate rotation of
an actor (in all axes).
Covers various factors affecting rotation animation
(like orientation of axes, parent rotation/orientation),
as well as trying to make rotations easier to visualise
(e.g. describing how rotation direction is affected by
those factors, how a rotation can be expected to look
when animated). Uses implicit animations for code examples.
Also refers to a full code example which uses ClutterState.
The simple key press example in the cookbook used a brittle
and incorrect switch statement to test modifier values. Instead,
use logical "&" of the state with the modifiers we're interested
in to check which keys were pressed.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2223
The cookbook should also include fully functional code examples. We can
even XInclude them into the docbook XML itself.
The examples should be built with the coobook, so that we can always
make sure they are up to date.
* elliot/cookbook-include-videos:
cookbook: Tweak so that videos sit inside a paragraph for better spacing
docs: Note the P_() macro in the HACKING file
cookbook: Added support for inline video
Conflicts:
doc/cookbook/Makefile.am
Explains how to make an actor transparent so that other actors
are visible through it.
Also explains a bit more generally about opacity and how
it's computed from the actor, container, and color; and how actor
visibility is affected by depth (fog) and depth order.
Amended Makefile to copy content of videos directory into
installation directories. Also copies videos and images
into the html/ directory during the build, so that the
built cookbook can be viewed locally (for testing without
having to install).
Added an XSLT template to transform Docbook <inlinemediaobject>
elements into HTML 5 <video> elements, with a fallback to
link to the video displayed for browsers without HTML 5 support.
Added note to "Contributing" appendix explaining how to put
video into a recipe.
Some apps or some use cases don't need to clear the stage on immediate
rendering GPUs. A media player playing a fullscreen video or a
tile-based game, for instance.
These apps are redrawing the whole screen, so we can avoid clearing the
color buffer when preparing to paint the stage, since there is no
blending with the stage color being performed.
We can add an private set of hints to ClutterStage, and expose accessors
for each potential hint; the first hint is the 'no-clear' one.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2058
This adds a publicly exposed experimental API for a 3D texture
backend. There is a feature flag which can be checked for whether 3D
textures are supported. Although we require OpenGL 1.2 which has 3D
textures in core, GLES only provides them through an extension so the
feature can be used to detect that.
The textures can be created with one of two new API functions :-
cogl_texture_3d_new_with_size
and
cogl_texture_3d_new_from_data
There is also internally a new_from_bitmap function. new_from_data is
implemented in terms of this function.
The two constructors are effectively the only way to upload data to a
3D texture. It does not work to call glTexImage2D with the
GL_TEXTURE_3D target so the virtual for cogl_texture_set_region does
nothing. It would be possible to make cogl_texture_get_data do
something sensible like returning all of the images as a single long
image but this is not currently implemented and instead the virtual
just always fails. We may want to add API specific to the 3D texture
backend to get and set a sub region of the texture.
All of those three functions can throw a GError. This will happen if
the GPU does not support 3D textures or it does not support NPOTs and
an NPOT size is requested. It will also fail if the FBO extension is
not supported and the COGL_TEXTURE_NO_AUTO_MIPMAP flag is not
given. This could be avoided by copying the code for the
GL_GENERATE_MIPMAP TexParameter fallback, but in the interests of
keeping the code simple this is not yet done.
This adds a couple of functions to cogl-texture-driver for uploading
3D data and querying the 3D proxy
texture. prep_gl_for_pixels_upload_full now also takes sets the
GL_UNPACK_IMAGE_HEIGHT parameter so that 3D textures can have padding
between the images. Whenever 3D texture is uploading, both the height
of the images and the height of all of the data is specified (either
explicitly or implicilty from the CoglBitmap) so that the image height
can be deduced by dividing by the depth.
There are many places in the texture backend that need to do
conversion using the CoglBitmap code. Currently none of these
functions can throw an error but they do return a value to indicate
failure. In future it would make sense if new texture functions could
throw an error and in that case they would want to use a CoglBitmap
error if the failure was due to the conversion. This moves the
internal CoglBitmap error from the quartz backend to be public in
cogl-bitmap.h so that it can be used in this way.
* elliot/cookbook-consistency:
cookbook: Fixed typo
cookbook: Fix build so CSS files get installed
cookbook: Moved paragraph where it logically belongs
cookbook: Added some judicious note elements
cookbook: Added more information for contributors
cookbook: Link out to docbook site
cookbook: Made docbook element usage consistent
cookbook: Additional selectors in CSS stylesheet
cookbook: Copy the CSS file into the HTML build directory
Introduces basic concepts (timelines, alphas, frames)
common to different parts of the Clutter animation API.
Gives a high level overview of the three different
approaches to animation (implicit, ClutterAnimator,
ClutterState).
Added a new recipe (based on the skeleton in the
animations section of the cookbook) about inverting
an animation by reversing the direction of its timeline.
Uses clutter_actor_animate() as the basic approach,
but mentions ClutterState and ClutterAnimator as well.
This adds a new API call to enable point sprite coordinate generation
for a material layer:
void
cogl_material_set_layer_point_sprite_coords_enabled (CoglHandle material,
int layer_index,
gboolean enable);
There is also a corresponding get function.
Enabling point sprite coords simply sets the GL_COORD_REPLACE of the
GL_POINT_SPRITE glTexEnv when flusing the material. There is no
separate application control for glEnable(GL_POINT_SPRITE). Instead it
is left permanently enabled under the assumption that it has no affect
unless GL_COORD_REPLACE is enabled for a texture unit.
http://bugzilla.openedhand.com/show_bug.cgi?id=2047
* cally-merge:
cally: Add introspection generation
cally: Improving cally doc
cally: Cleaning CallyText
cally: Refactoring "window:create" and "window:destroy" emission code
cally: Use proper backend information on CallyActor
cally: Check HAVE_CONFIG_H on cally-util.c
docs: Fix Cally documentation
cally: Clean up the headers
Add binaries of the Cally examples to the ignore file
docs: Add Cally API reference
Avoid to load cally module on a11y examples
Add accessibility tests
Initialize accessibility support on clutter_init
Rename some methods and includes to avoid -Wshadow warnings
Cally initialization code
Add Cally
I had changed the build so CSS files get put into
the HTML build directory; but done it in such
a way that they were then being ignored during
install. Fixed this.
There was a note about constants for keys and
where they are defined in Clutter header files; but
the sentence about where key modifiers are defined
was outside the note. Logically, they belong
together.
In some cases, there were blocks of text which
were really asides/interrupts to the flow, but
which weren't explicitly marked as such. I fixed
them by turning them into <note> blocks.
Made usage of docbook elements consistent across
recipes; to ensure the conventions are kept by others,
added a section about how to write and style recipes.
Make Cally follow the single-include header file policy of Clutter and
Cogl; this means making cally.h the single include header, and requires
a new cally-main.h file for the functions defined by cally.h.
Also:
• clean up the licensing notice and remove the FSF address;
• document the object structures (instance and class);
• G_GNUC_CONST-ify the get_type() functions;
• reduce the padding for CallyActor sub-classes;
• reduce the amount of headers included.
The documentation for cogl_vertex_buffer_indices_get_for_quads was
using ugly ASCII art to draw the diagrams. These have now been
replaced with PNG figures.
CoglMaterialWrapMode was missing from the cogl-sections.txt file so it
wasn't getting displayed. There were also no documented return values
from the getters.
Create two HTML versions of the cookbook:
• single page
• multiple pages
Use the online version of the DocBook XHTML XSL, and disable the PDF
generation until we can restore it.
Use a modified version of the Poky Handbook CSS for the HTML version of
the Cookbook.
Promote Elliot as author.
Re-license from the GPLv2.0 to the CC BY-NC-SA 2.0.
Apparently, xsltproc recognizes a directory if it has a '/' at the end
of its path, and not by doing the sensible thing and stat()'ing the
argument for the --output option.
This adds two new API calls- cogl_path_set_fill_rule and
cogl_path_get_fill_rule. This allows modifying the fill rule of the
current path. In addition to the previous default fill rule of
'even-odd' it now supports the 'non-zero' rule. The fill rule is a
property of the path (not the Cogl context) so creating a new path or
preserving a path with cogl_path_get_handle affects the fill rule.
Attached patch contains a cookbook recipe about key press event
handling.
It covers both a simple approach (connecting a callback to a
key-press-event signal which manually analyses the key and
modifiers), and a more complicated one based on a binding pool.
There's also some discussion of the two approaches.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2162
Signed-off-by: Emmanuele Bassi <ebassi@linux.intel.com>
The cookbook contains a commented-out recipe covering scaling images
inside a texture while retaining their aspect ratio; the attached
patch fleshes out this recipe.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2163
Signed-off-by: Emmanuele Bassi <ebassi@linux.intel.com>
This adds a separate variable name "CLUTTER_SONAME_INFIX" to define the
infix for the clutter library that gets linked. Currently the WINSYS
corresponds to the directory we enter when building to compile the
window system and input support, but it is desirable to be able to
define multiple flavours that use the same WINSYS but should result in
different library names.
For example we are planning to combine the eglx and eglnative window
systems into one "egl" winsys but we will need to preserve the current
library names for the eglx and eglnative flavours.
cogl_ortho is one of those APIs whos style was, for better or worse,
copied from OpenGL and for some inexplicable reason the near and far
arguments are inconsistent with the left, right, top, bottom arguments
because they don't take z coordinates they take a "distance" which
should be negative for a plane behind the viewer.
This updates the documentation to explain this.
* wip/deform-effect:
docs: Add DeformEffect and PageTurnEffect to the API reference
effect: Add PageTurnEffect
effect: Add DeformEffect
offscreen-effect: Traslate the modelview with the offsets
docs: Fix Effect subclassing section
It is often useful to determine if one actor is an ancestor of
another. Add a method to do that.
http://bugzilla.openedhand.com/show_bug.cgi?id=2162
Signed-off-by: Emmanuele Bassi <ebassi@linux.intel.com>
By default, ShaderEffect creates a fragment shader; in order to be able
to deprecate ClutterShader we need a way for ShaderEffect sub-classes to
create a vertex shader if needed - By using a write-only, constructor
only property.
ClutterShader has, internally, a ClutterShaderType enumeration that can
be used exactly for this. We just need to expose it and create a GObject
property for ClutterShaderEffect.
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().
• 3 general fixes (typos, copy/paste),
• ignore cogl-object-private.h,
• cogl_fixed_atani() was in reality cogl_fixed_atan(), fixed in commit
43564f05.
• Fix the cogl-vector section: sections must have a </SECTION> tag at
the end. Also the cogl-vector section was added in the middle of the
cogl-buffer one. Let's shiffle it out and add that </SECTION> tag.
This provides a mechanism for associating private data with any
CoglObject. We expect Clutter will use this to associate weak materials
with normal materials.
Various headers are build in builddirs (clutter-marshal.h, mkenums
headers and cogl-define.h) so we need to add the corresponding include
paths for gtk-doc to build its scanner.
ClutterInterval.compute_value() computes the new value given a progress
and copies it to a given GValue. Since most of the time we want to pass
that very same value to another function that copies it again, we should
have a compute_value() variant that stores that computed value inside
ClutterInterval and returns a pointer to it. This way we initialize the
result GValue just once and we never copy it, as long as the Interval
instance is valid.
* wip/constraints: (24 commits)
Add the Cogl API reference to the fixxref extra directories
Document the internal MetaGroup class
Remove the construct-only flag from ActorMeta:name
doc: Remove gtk-doc annotations from the json-glib copy
doc: Fix parameter documentation
Add named modifiers for Action and Constraint
Remove a redundant animation
Set the stage resizable in test-constraints
Use a 9 grid for the constraints test
Miscellaneous documentation fixes
docs: Document animating action and constraint properties
docs: Document BindConstraint and AlignConstraint
constraint: Rename BindConstraint:bind-axis
constraints: Add AlignConstraint
tests: Add a constraints interactive test
constraint: Add BindConstraint
actor: Implement Animatable
animation: Use the new Animatable API for custom properties
animatable: Add custom properties to Animatable
constraint: Add ClutterConstraint base class
...
Conflicts:
configure.ac
This adds a math utility API for handling 3 component, single precision
float vectors with the following; mostly self explanatory functions:
cogl_vector3_init
cogl_vector3_init_zero
cogl_vector3_equal
cogl_vector3_equal_with_epsilon
cogl_vector3_copy
cogl_vector3_free
cogl_vector3_invert
cogl_vector3_add
cogl_vector3_subtract
cogl_vector3_multiply_scalar
cogl_vector3_divide_scalar
cogl_vector3_normalize
cogl_vector3_magnitude
cogl_vector3_cross_product
cogl_vector3_dot_product
cogl_vector3_distance
Since the API is experimental you will need to define
COGL_ENABLE_EXPERIMENTAL_API before including cogl.h if you want to use
the API.
The Clutter cookbook has a chapter for textures. It would be useful to
provide a recipe on simple uses of ClutterCairoTexture as part of that.
Some suggested content is attached.
The ClutterActor API should have modifier methods for adding, removing
and retrieving Actions and Constraints using the ClutterActorMeta:name
property - mostly, for convenience.
In 125bded81 some comments were introduced to ClutterTexture
complaining that it can have a Cogl texture before being
realized. Clutter always assumes that the single GL context is current
so there is no need to wait until the actor is realized before setting
a texture. This patch replaces the comments with clarification that
this should not be a problem.
The patch also changes the documentation about the realized state in
various places to clarify that it is acceptable to create any Cogl
resources before the actor is realized.
http://bugzilla.openedhand.com/show_bug.cgi?id=2075
Previously, Cogl's texture coordinate system was effectively always
GL_REPEAT so that if an application specifies coordinates outside the
range 0→1 it would get repeated copies of the texture. It would
however change the mode to GL_CLAMP_TO_EDGE if all of the coordinates
are in the range 0→1 so that in the common case that the whole texture
is being drawn with linear filtering it will not blend in edge pixels
from the opposite sides.
This patch adds the option for applications to change the wrap mode
per layer. There are now three wrap modes: 'repeat', 'clamp-to-edge'
and 'automatic'. The automatic map mode is the default and it
implements the previous behaviour. The wrap mode can be changed for
the s and t coordinates independently. I've tried to make the
internals support setting the r coordinate but as we don't support 3D
textures yet I haven't exposed any public API for it.
The texture backends still have a set_wrap_mode virtual but this value
is intended to be transitory and it will be changed whenever the
material is flushed (although the backends are expected to cache it so
that it won't use too many GL calls). In my understanding this value
was always meant to be transitory and all primitives were meant to set
the value before drawing. However there were comments suggesting that
this is not the expected behaviour. In particular the vertex buffer
drawing code never set a wrap mode so it would end up with whatever
the texture was previously used for. These issues are now fixed
because the material will always set the wrap modes.
There is code to manually implement clamp-to-edge for textures that
can't be hardware repeated. However this doesn't fully work because it
relies on being able to draw the stretched parts using quads with the
same values for tx1 and tx2. The texture iteration code doesn't
support this so it breaks. This is a separate bug and it isn't
trivially solved.
When flushing a material there are now extra options to set wrap mode
overrides. The overrides are an array of values for each layer that
specifies an override for the s, t or r coordinates. The primitives
use this to implement the automatic wrap mode. cogl_polygon also uses
it to set GL_CLAMP_TO_BORDER mode for its trick to render sliced
textures. Although this code has been added it looks like the sliced
trick has been broken for a while and I haven't attempted to fix it
here.
I've added a constant to represent the maximum number of layers that a
material supports so that I can size the overrides array. I've set it
to 32 because as far as I can tell we have that limit imposed anyway
because the other flush options use a guint32 to store a flag about
each layer. The overrides array ends up adding 32 bytes to each flush
options struct which may be a concern.
http://bugzilla.openedhand.com/show_bug.cgi?id=2063
This adds three new API calls:
CoglHandle cogl_path_get()
void cogl_path_set(CoglHandle path)
CoglHandle cogl_path_copy(CoglHandle path)
All of the fields relating to the path have been moved from the Cogl
context to a new CoglPath handle type. The cogl context now just
contains a CoglPath handle. All of the existing path commands
manipulate the data in the current path handle. cogl_path_new now just
creates a new path handle and unrefs the old one.
The path handle can be stored for later with cogl_path_get. The path
can then be copied with cogl_path_copy. Internally it implements
copy-on-write semantics with an extra optimisation that it will only
copy the data if the new path is modified, but not if the original
path is modified. It can do this because the only way to modify a path
is by appending to it so the copied path is able to store its own path
length and only render the nodes up to that length. For this to work
the copied path also needs to keep its own copies of the path extents
because the parent path may change these by adding nodes.
The clip stack now uses the cogl_path_copy mechanism to store paths in
the stack instead of directly copying the data. This should save some
memory and processing time.
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.
Add clutter_actor_has_allocation(), a method meant to be used when
deciding whether to call clutter_actor_get_allocation_box() or any
of its wrappers.
The get_allocation_box() method will, in case the allocation is invalid,
perform a costly re-allocation cycle to ensure that the returned box
is valid. The has_allocation() method is meant to be used if we have an
actor calling get_allocation_box() from outside the place where the
allocation is always guaranteed to be valid.
Signed-off-by: Emmanuele Bassi <ebassi@linux.intel.com>
The create_context() and ensure_context() sections should be more clear
on the role of the functions, and their eventual caveats, like being
called multiple times.
We should explain what a "key frame" is for ClutterAnimator, possibly
with some sort of visual cue.
This allows me to demonstrate my poor skills at using Inkscape, as well
as my overall bad taste for graphics design.
It is conceivable that Container implementations might add children
outside of the Container::add() implementation - e.g. for packing at
a specific index. Since the addition (and removal) might happen outside
the common path we need to expose all the API that is implicitly called
by ClutterContainer when adding and removing a child - namely the
ChildMeta creation and destruction.
Embedding toolkits most likely will disable the event handling, so all
the input device code will not be executed. Unfortunately, the newly
added synthetic event generation of ENTER and LEAVE event pairs depends
on having input devices.
In order to unbreak things without reintroducing the madness of the
previous code we should allow embedding toolkits to just update the
state of an InputDevice by using the data contained inside the
ClutterEvent. This strategy has two obvious reasons:
• the embedding toolkit is creating a ClutterEvent by translating
a toolkit-native event anyway
• this is exactly what ClutterStage does when processing events
We are, essentially, deferring input device handling to the embedding
toolkits, just like we're deferring event handling to them.
If your OpenGL driver supports GLX_INTEL_swap_event that means when
glXSwapBuffers is called it returns immediatly and an XEvent is sent when
the actual swap has finished.
Clutter can use the events that notify swap completion as a means to
throttle rendering in the master clock without blocking the CPU and so it
should help improve the performance of CPU bound applications.
Gtk-doc is reporting a lot of false positives in the unused text file,
mostly because of new private files that have been added to Cogl but not
to the gtk-doc ignore list for the Cogl API reference.
Once the false positives have been removed we have a couple of really
missing symbols that should be added to the cogl-sections.txt file.
The PixelFormat bit and mask #defines should not be used and are there
mostly for convenience, so we can push them to the "private" sub-section
of the API reference.
This pushed Cogl's API reference coverage to 100%.
The only goal of using COGL buffers is to use them to create
textures. cogl_texture_new_from_buffer() is the new symbol to create
textures out of buffers.
This subclass of CoglBuffer aims at wrapping PBOs or other system
surfaces like DRM buffer objects. Two constructors are available:
cogl_pixel_buffer_new() with a size when you only care about the size of
the buffer (such a buffer can be used to store several texture data such
as the three planes of a I420 frame).
cogl_pixel_buffer_new_full() is more a 1:1 mapping between the data and
an underlying surface, with the possibility of having access to a low
level memory buffer that may have a stride.
Buffer objects are cool! This abstracts the buffer API first introduced
by GL_ARB_vertex_buffer_object and then extended to other objects.
The coglBuffer abstract class is intended to be the base class of all
the buffer objects, letting the user map() buffers. If the underlying
implementation does not support buffer objects (or only support VBO but
not FBO for instance), fallback paths should be provided.
* origin/cwiiis-stage-resize:
[stage-x11] Set the default size differently
[stage] Set default size correctly
Revert "[x11] Don't set actor size on ConfigureNotify"
[x11] Don't set actor size on ConfigureNotify
[stage] Now that get_geometry works, use it
[stage-x11] make get_geometry always get geometry
[stage] Get the current size correctly
[stage] Set minimum width/height to 1x1
[stage] Add set/get_minumum_size
ClutterAnimator is a class for managing the animation of multiple
properties of multiple actors over time with keyframing of values.
The Animator class is meant to be used to effectively describe
animations using the ClutterScript definition format, and to construct
complex implicit animations from the ground up.
Signed-off-by: Emmanuele Bassi <ebassi@linux.intel.com>
This adds three new texture backends.
- CoglTexture2D: This is a trimmed down version of CoglTexture2DSliced
which only supports a single texture and only works with the
GL_TEXTURE_2D target. The code is a lot simpler so it has a less
overheads than dealing with slices. Cogl will use this wherever
possible.
- CoglSubTexture: This is used to get a CoglHandle to represent a
subregion of another texture. The texture can be used as if it was a
standalone texture but it does not need to copy the resources.
- CoglAtlasTexture: This collects RGB and RGBA textures into a single
GL texture with the aim of reducing texture state changes and
increasing batching. The backend will try to manage the atlas and
may move the textures around to close gaps in the texture. By
default all textures will be placed in the atlas.
High level toolkits might wish to construct a PangoFontDescription and
then set it directly on a ClutterText actor proxy or sub-class.
ClutterText should have a :font-description property to set (and get)
the PangoFontDescription.
http://bugzilla.openedhand.com/show_bug.cgi?id=1960
* device-manager: (37 commits)
x11: Re-enable XI1 extension keyboards
x11: Always handle core device events before XI events
docs: Documentation fixes for DeviceManager
device-manager: Fix the signals definition
docs: Add sections for InputDevice and DeviceManager
docs: Add clutter_input_device_get_device_name()
tests: Print out the device details on motion
Always register core devices
device: Remove unused is_default member
win32: Experimental implementation of device support
tests: Print the device name, as well as its Id
x11: Fill out the :name property of the InputDevices
device: Add the :name property to InputDevice
x11: Store core devices on the X11 Backend singleton
device: Unset the cursor actor when leaving the stage
device: Add pointer actor getter
x11: Discard the LeaveNotify for off-stage ButtonRelease
device: Do not overwrite the stage for an InputDevice
event: Off-stage button releases have a click count of 1
event: Scroll events do not have click count
...
In the example for clutter_actor_animate the "x" and "y" properties
are floats so they need to be passed float values in the var args
otherwise it will crash. There was also a missing comma.
There were some other minor problems with the behaviours example which
would cause it not to compile.
An example of what could be the equivalent of
"RBG = REPLACE(TEXTURE)
A = MODULATE(PREVIOUS,TEXTURE)"
using the ARB_texture_env_combine extension was given, but it seems that
a few typo were left:
* remove a spurius GL_COMBINE_ALPHA
* use the _ALPHA variant of SRCN and OPERANDN when setting up the
alpha combiner
Allow the user of the ClutterMedia interface to specify a Pango font
description to display subtitles. Even if the underlying implementation
of the interface does not natively use Pange, it must be capable of
parsing the grammar that pango_font_description_from_string() accepts.
Since asking for ARGB by default is still somewhat experimental on X11
and not every toolkit or complex widgets (like WebKit) still do not like
dealing with ARGB visuals, we should switch back to RGB by default - now
that at least we know it works.
For applications (and toolkit integration libraries) that want to enable
the ClutterStage:use-alpha property there is a new function:
void clutter_x11_set_use_argb_visual (gboolean use_argb);
which needs to be called before clutter_init().
The CLUTTER_DISABLE_ARGB_VISUAL environment variable can still be used
to force this value off at run-time.
At first, those symbols were called {get,set}_subtitles_uri() but were
renamed to {get,set}_subtitle_uri() without updating the
clutter-section.txt file.
This fix makes gtk-doc document those symbols again.
Allow the user of the ClutterMedia interface to specify an external (as
in not multiplexed with the audio/video streams) location of a subtitle
stream.
* animate-layout-manager:
layout-manager: Document the animation support
layout-manager: Rewind the timeline in begin_animation()
box-layout: Remove the allocations hash table
docs: Clean up the README file
layout: Let begin_animation() return the Alpha
box-layout: Add knobs for controlling animations
box-layout: Animate layout properties
layout: Add animation support to LayoutManager
Add ActorBox animation methods
* stage-use-alpha:
tests: Use accessor methods for :use-alpha
stage: Add accessors for :use-alpha
tests: Allow setting the stage opacity in test-paint-wrapper
stage: Premultiply the stage color
stage: Composite the opacity with the alpha channel
glx: Always request an ARGB visual
stage: Add :use-alpha property
materials: Get the right blend function for alpha
ClutterActor checks, when destroying and reparenting, if the parent
actor implements the Container interface, and automatically calls the
remove() method to perform a clean removal.
Actors implementing Container, though, might have internal children;
that is, children that are not added through the Container API. It is
already possible to iterate through them using the Container API to
avoid breaking invariants - but calling clutter_actor_destroy() on
these children (even from the Container implementation, and thus outside
of Clutter's control) will either lead to leaks or to segmentation
faults.
Clutter needs a way to distinguish a clutter_actor_set_parent() done on
an internal child from one done on a "public" child; for this reason, a
push/pop pair of functions should be available to Actor implementations
to mark the section where they wish to add internal children:
➔ clutter_actor_push_internal ();
...
clutter_actor_set_parent (child1, parent);
clutter_actor_set_parent (child2, parent);
...
➔ clutter_actor_pop_internal ();
The set_parent() call will automatically set the newly added
INTERNAL_CHILD private flag on each child, and both
clutter_actor_destroy() and clutter_actor_unparent() will check for the
flag before deciding whether to call the Container's remove method.
ClutterLayoutManager does not have any state associated with it, and
defers all the state to its sub-classes.
The BoxLayout is thus in charge of controlling:
• whether or not animations should be used
• the duration of the animation
• the easing mode of the animation
By adding three new properties:
• ClutterBoxLayout:use-animations
• ClutterBoxLayout:easing-duration
• ClutterBoxLayout:easing-mode
And their relative accessors pairs we can make BoxLayout decide whether
or not, and with which parameters, call the begin_animation() method of
ClutterLayoutManager.
The test-box-layout has been modified to reflect this new functionality,
by checking the key-press event for the 'a' key symbol to toggle the use
of animations.
In order to animate a fluid layout we cannot use the common animation
code paths as they will override the size request and allocation paths
that are handled by the layout manager itself.
One way to introduce animations in the allocation sequence is to use a
Timeline and an Alpha to compute a progress value and then use that
value to interpolate an ActorBox between the initial and final states of
the animation - with the initial state being the last allocation of the
child prior to the animation start, and the final state the allocation
of the child at the end; for every frame of the Timeline we then queue a
relayout on the layout manager's container, which will result in an
animation.
ClutterLayoutManager is the most likely place to add a generic API for
beginning and ending an animation, as well as the place to provide a
default code path to create the ancillary Timeline and Alpha instances
needed to drive the animation.
A LayoutManager sub-class will need to:
• call clutter_layout_manager_begin_animation() whenever it should
animate between two states, for instance: whenever a layout property
changes value;
• eventually override begin_animation() and end_animation() in case
further state needs to be set up, and then chain up to the default
implementation provided by LayoutManager;
• if a completely different implementation is required, the layout
manager sub-class should override begin_animation(), end_animation()
and get_animation_progress().
Inside the allocate() implementation the sub-class should also
interpolate between the last known allocation of a child and the newly
computed allocation.
ClutterActorBox should have an interpolate() method that allows to
compute the intermediate values between two states, given a progress
value, e.g.:
clutter_actor_box_interpolate (start, end, alpha, &result);
Another utility method, useful for layout managers, is a modifier
that clamps the members of the actor box to the nearest integer
value.
When getting signals from higher level toolkits, occasionally
one wants access to the underlying event; say for a Button
widget's "clicked" signal, to get the keyboard state.
Rather than having all of the highlevel widgets emit
ClutterEvent just for the more unusual use cases,
add a global function to access the event state.
http://bugzilla.openedhand.com/show_bug.cgi?id=1888
Signed-off-by: Emmanuele Bassi <ebassi@linux.intel.com>
This adds a new texture backend which represents a sub texture of a
larger texture. The texture is created with a reference to the full
texture and a set of coordinates describing the region. The backend
simply defers to the full texture for all operations and maps the
coordinates to the other range. You can also use coordinates outside
the range [0,1] to create a repeated version of the full texture.
A new public API function called cogl_texture_new_from_sub_texture is
available to create the sub texture.
* text-direction:
docs: Add text-direction accessors
Set the default language on the Pango context
actor: Set text direction on parenting
tests: Display the index inside text-box-layout
box-layout: Honour :text-direction
text: Dirty layout cache on text direction changes
actor: Add :text-direction property
Use the newly added ClutterTextDirection enumeration
Add ClutterTextDirection enumeration
We should always recurse into the doc/ directory; whether we should then
recurse into reference/, cookbook/ and manual/ is a matter of specific
configure-time flags.
• Make the manual a DevHelp book
• Make the generation of PDFs of the cookbook and the manual optional
• Consequently, make the hard dependency on jw optional
• Clean up the checks and build for the additional documentation
Instead of creating stand-alone HTML files, use XSLT to transform the
DocBook into a DevHelp file, so that we can read the Cookbook inside
DevHelp -- just like the API reference.
The first recipe shows how to be notified when the relative position
and size of an actor changes using the notify:: signal on the actor's
dimensional and positional properties.
The "Clutter Cookbook" is a document designed to contain solutions
to common problems applications developers might encounter when using
Clutter. It is meant as a companion to the API reference but it
requires knowledge of the Clutter API and framework.
The ClutterLayoutMeta instances should be created on demand, whenever
the layout manager needs them - if the layout manager supports layout
properties.
This removes the requirement to call add_child_meta() and
remove_child_meta() on add and remove respectively; it also simplifies
the implementation of LayoutManager sub-classes since we can add
fallback code in the base abstract class.
Eventually, this will also lead to an easier to implement ClutterScript
parser for layout properties.
With the new scheme, the ClutterLayoutMeta instance is created whenever
the layout manager tries to access it; if there isn't an instance
already attached to the container's child, one is created -- assuming
that the LayoutManager sub-class has overridden the
get_child_meta_type() virtual function and it's returning a valid GType.
We can also provide a default implementation for create_child_meta(),
by getting the GType and instantiating a ClutterLayoutMeta with all the
fields already set. If the layout manager requires more work then it can
obviously override the default implementation (and even chain up to it).
The ClutterBox actor has been updated, as well as the ClutterBoxLayout
layout manager, to take advantage of the changes of LayoutManager.
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.
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.
The Clutter API reference has an index of the symbols for each minor
version, and a list of deprecated symbols. The Cogl API reference
should have the same layout.
The order in which the MacPorts are installed is important otherwise we open
the user up to a world of pain.
This patch also tweaks the OS X docs to follow the formatting of the rest of
the docs and to discuss the option of GtkDoc.
http://bugzilla.openedhand.com/show_bug.cgi?id=1865
cogl_clip_push() which accepts a rectangle in model space shouldn't have
been defined to take x,y,width,height arguments because this isn't consistant
with other Cogl API dealing with model space rectangles. If you are using a
coordinate system with the origin at the center and the y+ extending up,
then x,y,width,height isn't as natural as (x0,y0)(x1,y1). This API has
now been replace with cogl_clip_push_rectangle()
(As a general note: the Cogl API should only use the x,y,width,height style
when the appropriate coordinate space is defined by Cogl to have a top left
origin. E.g. window coordinates, or potentially texture coordinates)
cogl_clip_push_window_rect() shouldn't have been defined to take float
arguments since we only clip with integral pixel precision. We also
shouldn't have abbreviated "rectangle". This API has been replaced with
cogl_clip_push_window_rectangle()
cogl_clip_ensure() wasn't documented at all in Clutter 1.0 and probably
no one even knew it existed. This API isn't useful, and so it's now
deprecated. If no one complains we may remove the API altogether for
Clutter 1.2.
cogl_clip_stack_save() and cogl_clip_stack_restore() were originally added
to allow us to save/restore the clip when switching to/from offscreen
rendering. Now that offscreen draw buffers are defined to own their clip
state and the state will be automatically saved and restored this API is now
redundant and so deprecated.
Just like CLUTTER_CHECK_VERSION does version checking at compile
time, we need a way to verify the version of the library that we
are linking against. This is mostly needed for language bindings
and for run-time loadable modules -- when we'll get those.
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.
• Fix list_stages() and peek_stages() documentation
• Fix clutter_text_set_preedit_string() arguments in the header
to match source and documentation
• Add clutter_units_cm() to the private section for Units
• Rename the LayoutManager section
• Add FlowLayout:homogeneous accessors
* layout-manager: (50 commits)
docs: Reword a link
layout, docs: Add more documentation to LayoutManager
layout, docs: Fix description of Bin properties
layout, bin: Use ceilf() instead of casting to int
layout, docs: Add long description for FlowLayout
layout, box: Clean up
layout, box: Write long description for Box
layout, docs: Remove unused functions
layout: Document BoxLayout
layout: Add BoxLayout, a single line layout manager
layout: Report the correct size of FlowLayout
layout: Resizing the stage resizes the FlowLayout box
layout: Use the get_request_mode() getter in BinLayout
layout: Change the request-mode along with the orientation
actor: Add set_request_mode() method
[layout] Remove FlowLayout:wrap
[layout] Rename BinLayout and FlowLayout interactive tests
[layout] Skip invisible children in FlowLayout
[layout] Clean up and document FlowLayout
[layout] Snap children of FlowLayout to column/row
...
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.
Input Methods require to be able to set a "pre-edit string", that is
a string that it's just displayed into the Text actor without being
committed to the actor's buffer. The string might require custom Pango
attributes, and an update of the cursor position.
FlowLayout is a layout manager that arranges its children in a
reflowing line; the orientation controls the major axis for the
layout: horizontal, for reflow on the Y axis, and vertical, for
reflow on the X axis.
The BinLayout should store a pointer to the Container that it is
using it as the layout manager.
This allows us to fix the API and drop the additional Container
arguments from set_alignment() and get_alignment().
This also allows us to add a ClutterBinLayout::add() method which
adds an actor and sets the alignment policies without dealing with
variadic arguments functions and GValue (de)marshalling.
Use the LayoutManager API to set a back pointer to the Box actor
inside the LayoutManager used by the box.
This also allows us to replace the LayoutManager on a Box, since
the LayoutManager will be able to replace all the metadata if
needed.
The LayoutManager implementation might opt to take a back pointer
to the Container that is using the layout instance; this allows
direct access to the container itself from within the implementation.
The ClutterBox::add method is a simple wrapper around the Container
add_actor() method and the LayoutManager layout properties API. It
allows adding an actor to a Box and setting the layout properties in
one call.
If the LayoutManager used by the Box does not support layout properties
then the add() method short-circuits out.
Along with the varargs version of the method there's also a vector-based
variant, for language bindings to use.
Instead of overloading ClutterChildMeta with both container and layout
metadata and delegate to every LayoutManager implementation to keep a
backpointer to the layout manager instance, we can simply subclass
ChildMeta into LayoutMeta and presto! everything works out pretty well
for everyone.
The chapter on how to subclass ClutterActor inside the API reference for
Clutter is still using ClutterUnit and referencing to concepts that have
been changed since the document was written.
ClutterBehaviourPath has been changed and ClutterBehaviourBspline has
been removed; now we use ClutterPath everywhere we need to describe a
path. This warrants a chapter in the migration guide.
The get_type() function for ClutterInterval is missing from the
known GObject types, so gtk-doc doesn't know that it has to
introspect it for hierarchy, properties and signals.
Currently, to update a property inside an animation you have to
get the interval for that property and then call the set_final_value()
method.
We can provide a simpler, bind()-like method for the convenience of
the developers that just validates everything and then calls the
Interval.set_final_value().
The version number in the title made sense when we were breaking
API with every minor release. Now that we're API stable we can
drop that and make the output in Devhelp and on the website slightly
more good looking.
We should follow the convention for boxed types initializers of:
<type_name>_from_<another_type> (boxed, value)
For ClutterUnits as well; so:
clutter_units_pixels -> clutter_units_from_pixels
clutter_units_em -> clutter_units_from_em
...
We should still keep the short-hand version as a macro, though.
It might be desirable for some applications and/or platforms to get
every motion event that was delivered to Clutter from the windowing
backend. By adding a per-stage flag we can bypass the throttling
done when processing the events.
http://bugzilla.openedhand.com/show_bug.cgi?id=1665
It would be useful inside a custom actor's paint function to be able to
tell if this is a primary paint call, or if we are in fact painting on
behalf of a clone.
In Mutter we have an optimization not to paint occluded windows; this is
desirable for the windows per se, to conserve bandwith to the card, but
if something like an application switcher is using clones of these windows,
they will not get painted either; currently we have no way of
differentiating between the two.
Fixes bug:
http://bugzilla.openedhand.com/show_bug.cgi?id=1685
Currently, the transformation matrix for an actor is constructed
from scenegraph-related accessors. An actor, though, can call COGL
API to add new transformations inside the paint() implementation,
for instance:
static void
my_foo_paint (ClutterActor *a)
{
...
cogl_translate (-scroll_x, -scroll_y, 0);
...
}
Unfortunately these transformations will be completely ignored by
the scenegraph machinery; for instance, getting the actor-relative
coordinates from event coordinates is going to break badly because
of this.
In order to make the scenegraph aware of the potential of additional
transformations, we need a ::apply_transform() virtual function. This
vfunc will pass a CoglMatrix which can be used to apply additional
operations:
static void
my_foo_apply_transform (ClutterActor *a, CoglMatrix *m)
{
CLUTTER_ACTOR_CLASS (my_foo_parent_class)->apply_transform (a, m);
...
cogl_matrix_translate (m, -scroll_x, -scroll_y, 0);
...
}
The ::paint() implementation will be called with the actor already
using the newly applied transformation matrix, as expected:
static void
my_foo_paint (ClutterActor *a)
{
...
}
The ::apply_transform() implementations *must* chain up, so that the
various transformations of each class are preserved. The default
implementation inside ClutterActor applies all the transformations
defined by the scenegraph-related accessors.
Actors performing transformations inside the paint() function will
continue to work as previously.
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.
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.
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.
The clutter_actor_pick() function just emits the ::pick signal
on the actor. Nobody should be using it, since the paint() method
is already context sensitive and will result in a ::pick emission
by itself. The clutter_actor_pick() is just confusing things.
