mirror of
https://github.com/brl/mutter.git
synced 2024-12-03 05:10:40 -05:00
f5dac3a5d9
Group all the three config files from clutter/cogl/meta into one and also remove unnused configurations and replace duplicated ones This also fixes Cogl usage of HAS_X11/HAS_XLIB to match the expected build options Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3368>
248 lines
9.9 KiB
C
248 lines
9.9 KiB
C
/*
|
|
* Clutter.
|
|
*
|
|
* An OpenGL based 'interactive canvas' library.
|
|
*
|
|
* Copyright (C) 2010 Intel Corporation.
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2 of the License, or (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
|
|
*
|
|
* Author:
|
|
* Emmanuele Bassi <ebassi@linux.intel.com>
|
|
*/
|
|
|
|
/**
|
|
* ClutterConstraint:
|
|
*
|
|
* Abstract class for constraints on position or size
|
|
*
|
|
* #ClutterConstraint is a base abstract class for modifiers of a #ClutterActor
|
|
* position or size.
|
|
*
|
|
* A #ClutterConstraint sub-class should contain the logic for modifying
|
|
* the position or size of the #ClutterActor to which it is applied, by
|
|
* updating the actor's allocation. Each #ClutterConstraint can change the
|
|
* allocation of the actor to which they are applied by overriding the
|
|
* #ClutterConstraintClass.update_allocation() virtual function.
|
|
*
|
|
* ## Using Constraints
|
|
*
|
|
* Constraints can be used with fixed layout managers, like
|
|
* #ClutterFixedLayout, or with actors implicitly using a fixed layout
|
|
* manager, like #ClutterGroup and #ClutterStage.
|
|
*
|
|
* Constraints provide a way to build user interfaces by using
|
|
* relations between #ClutterActors, without explicit fixed
|
|
* positioning and sizing, similarly to how fluid layout managers like
|
|
* #ClutterBoxLayout lay out their children.
|
|
*
|
|
* Constraints are attached to a #ClutterActor, and are available
|
|
* for inspection using clutter_actor_get_constraints().
|
|
*
|
|
* Clutter provides different implementation of the #ClutterConstraint
|
|
* abstract class, for instance:
|
|
*
|
|
* - #ClutterAlignConstraint, a constraint that can be used to align
|
|
* an actor to another one on either the horizontal or the vertical
|
|
* axis, using a normalized value between 0 and 1.
|
|
* - #ClutterBindConstraint, a constraint binds the X, Y, width or height
|
|
* of an actor to the corresponding position or size of a source actor,
|
|
* with or without an offset.
|
|
* - #ClutterSnapConstraint, a constraint that "snaps" together the edges
|
|
* of two #ClutterActors; if an actor uses two constraints on both its
|
|
* horizontal or vertical edges then it can also expand to fit the empty
|
|
* space.
|
|
*
|
|
* The [constraints example](https://git.gnome.org/browse/clutter/tree/examples/constraints.c?h=clutter-1.18)
|
|
* uses various types of #ClutterConstraints to lay out three actors on a
|
|
* resizable stage. Only the central actor has an explicit size, and no
|
|
* actor has an explicit position.
|
|
*
|
|
* - The #ClutterActor with #ClutterActor:name `layerA` is explicitly
|
|
* sized to 100 pixels by 25 pixels, and it's added to the #ClutterStage
|
|
* - two #ClutterAlignConstraints are used to anchor `layerA` to the
|
|
* center of the stage, by using 0.5 as the alignment #ClutterAlignConstraint:factor on
|
|
* both the X and Y axis
|
|
* - the #ClutterActor with #ClutterActor:name `layerB` is added to the
|
|
* #ClutterStage with no explicit size
|
|
* - the #ClutterActor:x and #ClutterActor:width of `layerB` are bound
|
|
* to the same properties of `layerA` using two #ClutterBindConstraint
|
|
* objects, thus keeping `layerB` aligned to `layerA`
|
|
* - the top edge of `layerB` is snapped together with the bottom edge
|
|
* of `layerA`; the bottom edge of `layerB` is also snapped together with
|
|
* the bottom edge of the #ClutterStage; an offset is given to the two
|
|
* #ClutterSnapConstraintss to allow for some padding; since `layerB` is
|
|
* snapped between two different #ClutterActors, its height is stretched
|
|
* to match the gap
|
|
* - the #ClutterActor with #ClutterActor:name `layerC` mirrors `layerB`,
|
|
* snapping the top edge of the #ClutterStage to the top edge of `layerC`
|
|
* and the top edge of `layerA` to the bottom edge of `layerC`
|
|
*
|
|
* You can try resizing interactively the #ClutterStage and verify
|
|
* that the three #ClutterActors maintain the same position and
|
|
* size relative to each other, and to the #ClutterStage.
|
|
*
|
|
* It is important to note that Clutter does not avoid loops or
|
|
* competing constraints; if two or more #ClutterConstraints
|
|
* are operating on the same positional or dimensional attributes of an
|
|
* actor, or if the constraints on two different actors depend on each
|
|
* other, then the behavior is undefined.
|
|
*
|
|
* ## Implementing a ClutterConstraint
|
|
*
|
|
* Creating a sub-class of #ClutterConstraint requires the
|
|
* implementation of the #ClutterConstraintClass.update_allocation()
|
|
* virtual function.
|
|
*
|
|
* The `update_allocation()` virtual function is called during the
|
|
* allocation sequence of a #ClutterActor, and allows any #ClutterConstraint
|
|
* attached to that actor to modify the allocation before it is passed to
|
|
* the actor's #ClutterActorClass.allocate() implementation.
|
|
*
|
|
* The #ClutterActorBox passed to the `update_allocation()` implementation
|
|
* contains the original allocation of the #ClutterActor, plus the eventual
|
|
* modifications applied by the other #ClutterConstraints, in the same order
|
|
* the constraints have been applied to the actor.
|
|
*
|
|
* It is not necessary for a #ClutterConstraint sub-class to chain
|
|
* up to the parent's implementation.
|
|
*
|
|
* If a #ClutterConstraint is parametrized - i.e. if it contains
|
|
* properties that affect the way the constraint is implemented - it should
|
|
* call clutter_actor_queue_relayout() on the actor to which it is attached
|
|
* to whenever any parameter is changed. The actor to which it is attached
|
|
* can be recovered at any point using clutter_actor_meta_get_actor().
|
|
*/
|
|
|
|
#include "config.h"
|
|
|
|
#include <string.h>
|
|
|
|
#include "clutter/clutter-constraint-private.h"
|
|
|
|
#include "clutter/clutter-actor.h"
|
|
#include "clutter/clutter-actor-meta-private.h"
|
|
#include "clutter/clutter-private.h"
|
|
|
|
G_DEFINE_ABSTRACT_TYPE (ClutterConstraint,
|
|
clutter_constraint,
|
|
CLUTTER_TYPE_ACTOR_META);
|
|
|
|
static void
|
|
constraint_update_allocation (ClutterConstraint *constraint,
|
|
ClutterActor *actor,
|
|
ClutterActorBox *allocation)
|
|
{
|
|
}
|
|
|
|
static void
|
|
constraint_update_preferred_size (ClutterConstraint *constraint,
|
|
ClutterActor *actor,
|
|
ClutterOrientation direction,
|
|
float for_size,
|
|
float *minimum_size,
|
|
float *natural_size)
|
|
{
|
|
}
|
|
|
|
static void
|
|
clutter_constraint_set_enabled (ClutterActorMeta *meta,
|
|
gboolean is_enabled)
|
|
{
|
|
ClutterActorMetaClass *parent_class =
|
|
CLUTTER_ACTOR_META_CLASS (clutter_constraint_parent_class);
|
|
ClutterActor *actor;
|
|
|
|
actor = clutter_actor_meta_get_actor (meta);
|
|
if (actor)
|
|
clutter_actor_queue_relayout (actor);
|
|
|
|
parent_class->set_enabled (meta, is_enabled);
|
|
}
|
|
|
|
static void
|
|
clutter_constraint_class_init (ClutterConstraintClass *klass)
|
|
{
|
|
ClutterActorMetaClass *actor_meta_class = CLUTTER_ACTOR_META_CLASS (klass);
|
|
|
|
actor_meta_class->set_enabled = clutter_constraint_set_enabled;
|
|
|
|
klass->update_allocation = constraint_update_allocation;
|
|
klass->update_preferred_size = constraint_update_preferred_size;
|
|
}
|
|
|
|
static void
|
|
clutter_constraint_init (ClutterConstraint *self)
|
|
{
|
|
}
|
|
|
|
/*< private >
|
|
* clutter_constraint_update_allocation:
|
|
* @constraint: a #ClutterConstraint
|
|
* @actor: a #ClutterActor
|
|
* @allocation: (inout): the allocation to modify
|
|
*
|
|
* Asks the @constraint to update the @allocation of a #ClutterActor.
|
|
*
|
|
* Returns: %TRUE if the allocation was updated
|
|
*/
|
|
gboolean
|
|
clutter_constraint_update_allocation (ClutterConstraint *constraint,
|
|
ClutterActor *actor,
|
|
ClutterActorBox *allocation)
|
|
{
|
|
ClutterActorBox old_alloc;
|
|
|
|
g_return_val_if_fail (CLUTTER_IS_CONSTRAINT (constraint), FALSE);
|
|
g_return_val_if_fail (CLUTTER_IS_ACTOR (actor), FALSE);
|
|
g_return_val_if_fail (allocation != NULL, FALSE);
|
|
|
|
old_alloc = *allocation;
|
|
|
|
CLUTTER_CONSTRAINT_GET_CLASS (constraint)->update_allocation (constraint,
|
|
actor,
|
|
allocation);
|
|
|
|
return !clutter_actor_box_equal (allocation, &old_alloc);
|
|
}
|
|
|
|
/**
|
|
* clutter_constraint_update_preferred_size:
|
|
* @constraint: a #ClutterConstraint
|
|
* @actor: a #ClutterActor
|
|
* @direction: a #ClutterOrientation
|
|
* @for_size: the size in the opposite direction
|
|
* @minimum_size: (inout): the minimum size to modify
|
|
* @natural_size: (inout): the natural size to modify
|
|
*
|
|
* Asks the @constraint to update the size request of a #ClutterActor.
|
|
*/
|
|
void
|
|
clutter_constraint_update_preferred_size (ClutterConstraint *constraint,
|
|
ClutterActor *actor,
|
|
ClutterOrientation direction,
|
|
float for_size,
|
|
float *minimum_size,
|
|
float *natural_size)
|
|
{
|
|
g_return_if_fail (CLUTTER_IS_CONSTRAINT (constraint));
|
|
g_return_if_fail (CLUTTER_IS_ACTOR (actor));
|
|
|
|
CLUTTER_CONSTRAINT_GET_CLASS (constraint)->update_preferred_size (constraint, actor,
|
|
direction,
|
|
for_size,
|
|
minimum_size,
|
|
natural_size);
|
|
}
|