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mutter-performance-source/clutter/clutter-clone.c

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/*
* Clutter.
*
* An OpenGL based 'interactive canvas' library.
*
* Copyright (C) 2008 Intel Corporation.
*
* Authored By: Robert Bragg <robert@linux.intel.com>
*
* 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/>.
*/
/**
* SECTION:clutter-clone
* @short_description: An actor that displays a clone of a source actor
*
* #ClutterClone is a #ClutterActor which draws with the paint
* function of another actor, scaled to fit its own allocation.
*
* #ClutterClone can be used to efficiently clone any other actor.
*
* <note><para>This is different from clutter_texture_new_from_actor()
* which requires support for FBOs in the underlying GL
* implementation.</para></note>
*
* #ClutterClone is available since Clutter 1.0
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "clutter-actor-private.h"
#include "clutter-clone.h"
#include "clutter-debug.h"
#include "clutter-main.h"
#include "clutter-paint-volume-private.h"
#include "clutter-private.h"
#include "cogl/cogl.h"
G_DEFINE_TYPE (ClutterClone, clutter_clone, CLUTTER_TYPE_ACTOR);
enum
{
PROP_0,
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PROP_SOURCE,
PROP_LAST
};
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static GParamSpec *obj_props[PROP_LAST];
#define CLUTTER_CLONE_GET_PRIVATE(obj) (G_TYPE_INSTANCE_GET_PRIVATE ((obj), CLUTTER_TYPE_CLONE, ClutterClonePrivate))
struct _ClutterClonePrivate
{
ClutterActor *clone_source;
};
static void clutter_clone_set_source_internal (ClutterClone *clone,
ClutterActor *source);
static void
clutter_clone_get_preferred_width (ClutterActor *self,
Remove Units from the public API With the recent change to internal floating point values, ClutterUnit has become a redundant type, defined to be a float. All integer entry points are being internally converted to floating point values to be passed to the GL pipeline with the least amount of conversion. ClutterUnit is thus exposed as just a "pixel with fractionary bits", and not -- as users might think -- as generic, resolution and device independent units. not that it was the case, but a definitive amount of people was convinced it did provide this "feature", and was flummoxed about the mere existence of this type. So, having ClutterUnit exposed in the public API doubles the entry points and has the following disadvantages: - we have to maintain twice the amount of entry points in ClutterActor - we still do an integer-to-float implicit conversion - we introduce a weird impedance between pixels and "pixels with fractionary bits" - language bindings will have to choose what to bind, and resort to manually overriding the API + *except* for language bindings based on GObject-Introspection, as they cannot do manual overrides, thus will replicate the entire set of entry points For these reason, we should coalesces every Actor entry point for pixels and for ClutterUnit into a single entry point taking a float, like: void clutter_actor_set_x (ClutterActor *self, gfloat x); void clutter_actor_get_size (ClutterActor *self, gfloat *width, gfloat *height); gfloat clutter_actor_get_height (ClutterActor *self); etc. The issues I have identified are: - we'll have a two cases of compiler warnings: - printf() format of the return values from %d to %f - clutter_actor_get_size() taking floats instead of unsigned ints - we'll have a problem with varargs when passing an integer instead of a floating point value, except on 64bit platforms where the size of a float is the same as the size of an int To be clear: the *intent* of the API should not change -- we still use pixels everywhere -- but: - we remove ambiguity in the API with regard to pixels and units - we remove entry points we get to maintain for the whole 1.0 version of the API - we make things simpler to bind for both manual language bindings and automatic (gobject-introspection based) ones - we have the simplest API possible while still exposing the capabilities of the underlying GL implementation
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gfloat for_height,
gfloat *min_width_p,
gfloat *natural_width_p)
{
ClutterClonePrivate *priv = CLUTTER_CLONE (self)->priv;
ClutterActor *clone_source = priv->clone_source;
Remove Units from the public API With the recent change to internal floating point values, ClutterUnit has become a redundant type, defined to be a float. All integer entry points are being internally converted to floating point values to be passed to the GL pipeline with the least amount of conversion. ClutterUnit is thus exposed as just a "pixel with fractionary bits", and not -- as users might think -- as generic, resolution and device independent units. not that it was the case, but a definitive amount of people was convinced it did provide this "feature", and was flummoxed about the mere existence of this type. So, having ClutterUnit exposed in the public API doubles the entry points and has the following disadvantages: - we have to maintain twice the amount of entry points in ClutterActor - we still do an integer-to-float implicit conversion - we introduce a weird impedance between pixels and "pixels with fractionary bits" - language bindings will have to choose what to bind, and resort to manually overriding the API + *except* for language bindings based on GObject-Introspection, as they cannot do manual overrides, thus will replicate the entire set of entry points For these reason, we should coalesces every Actor entry point for pixels and for ClutterUnit into a single entry point taking a float, like: void clutter_actor_set_x (ClutterActor *self, gfloat x); void clutter_actor_get_size (ClutterActor *self, gfloat *width, gfloat *height); gfloat clutter_actor_get_height (ClutterActor *self); etc. The issues I have identified are: - we'll have a two cases of compiler warnings: - printf() format of the return values from %d to %f - clutter_actor_get_size() taking floats instead of unsigned ints - we'll have a problem with varargs when passing an integer instead of a floating point value, except on 64bit platforms where the size of a float is the same as the size of an int To be clear: the *intent* of the API should not change -- we still use pixels everywhere -- but: - we remove ambiguity in the API with regard to pixels and units - we remove entry points we get to maintain for the whole 1.0 version of the API - we make things simpler to bind for both manual language bindings and automatic (gobject-introspection based) ones - we have the simplest API possible while still exposing the capabilities of the underlying GL implementation
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if (clone_source == NULL)
{
if (min_width_p)
*min_width_p = 0;
if (natural_width_p)
*natural_width_p = 0;
}
else
clutter_actor_get_preferred_width (clone_source,
for_height,
min_width_p,
natural_width_p);
}
static void
clutter_clone_get_preferred_height (ClutterActor *self,
Remove Units from the public API With the recent change to internal floating point values, ClutterUnit has become a redundant type, defined to be a float. All integer entry points are being internally converted to floating point values to be passed to the GL pipeline with the least amount of conversion. ClutterUnit is thus exposed as just a "pixel with fractionary bits", and not -- as users might think -- as generic, resolution and device independent units. not that it was the case, but a definitive amount of people was convinced it did provide this "feature", and was flummoxed about the mere existence of this type. So, having ClutterUnit exposed in the public API doubles the entry points and has the following disadvantages: - we have to maintain twice the amount of entry points in ClutterActor - we still do an integer-to-float implicit conversion - we introduce a weird impedance between pixels and "pixels with fractionary bits" - language bindings will have to choose what to bind, and resort to manually overriding the API + *except* for language bindings based on GObject-Introspection, as they cannot do manual overrides, thus will replicate the entire set of entry points For these reason, we should coalesces every Actor entry point for pixels and for ClutterUnit into a single entry point taking a float, like: void clutter_actor_set_x (ClutterActor *self, gfloat x); void clutter_actor_get_size (ClutterActor *self, gfloat *width, gfloat *height); gfloat clutter_actor_get_height (ClutterActor *self); etc. The issues I have identified are: - we'll have a two cases of compiler warnings: - printf() format of the return values from %d to %f - clutter_actor_get_size() taking floats instead of unsigned ints - we'll have a problem with varargs when passing an integer instead of a floating point value, except on 64bit platforms where the size of a float is the same as the size of an int To be clear: the *intent* of the API should not change -- we still use pixels everywhere -- but: - we remove ambiguity in the API with regard to pixels and units - we remove entry points we get to maintain for the whole 1.0 version of the API - we make things simpler to bind for both manual language bindings and automatic (gobject-introspection based) ones - we have the simplest API possible while still exposing the capabilities of the underlying GL implementation
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gfloat for_width,
gfloat *min_height_p,
gfloat *natural_height_p)
{
ClutterClonePrivate *priv = CLUTTER_CLONE (self)->priv;
ClutterActor *clone_source = priv->clone_source;
Remove Units from the public API With the recent change to internal floating point values, ClutterUnit has become a redundant type, defined to be a float. All integer entry points are being internally converted to floating point values to be passed to the GL pipeline with the least amount of conversion. ClutterUnit is thus exposed as just a "pixel with fractionary bits", and not -- as users might think -- as generic, resolution and device independent units. not that it was the case, but a definitive amount of people was convinced it did provide this "feature", and was flummoxed about the mere existence of this type. So, having ClutterUnit exposed in the public API doubles the entry points and has the following disadvantages: - we have to maintain twice the amount of entry points in ClutterActor - we still do an integer-to-float implicit conversion - we introduce a weird impedance between pixels and "pixels with fractionary bits" - language bindings will have to choose what to bind, and resort to manually overriding the API + *except* for language bindings based on GObject-Introspection, as they cannot do manual overrides, thus will replicate the entire set of entry points For these reason, we should coalesces every Actor entry point for pixels and for ClutterUnit into a single entry point taking a float, like: void clutter_actor_set_x (ClutterActor *self, gfloat x); void clutter_actor_get_size (ClutterActor *self, gfloat *width, gfloat *height); gfloat clutter_actor_get_height (ClutterActor *self); etc. The issues I have identified are: - we'll have a two cases of compiler warnings: - printf() format of the return values from %d to %f - clutter_actor_get_size() taking floats instead of unsigned ints - we'll have a problem with varargs when passing an integer instead of a floating point value, except on 64bit platforms where the size of a float is the same as the size of an int To be clear: the *intent* of the API should not change -- we still use pixels everywhere -- but: - we remove ambiguity in the API with regard to pixels and units - we remove entry points we get to maintain for the whole 1.0 version of the API - we make things simpler to bind for both manual language bindings and automatic (gobject-introspection based) ones - we have the simplest API possible while still exposing the capabilities of the underlying GL implementation
2009-05-06 15:44:47 +00:00
if (clone_source == NULL)
{
if (min_height_p)
*min_height_p = 0;
if (natural_height_p)
*natural_height_p = 0;
}
else
clutter_actor_get_preferred_height (clone_source,
for_width,
min_height_p,
natural_height_p);
}
static void
clutter_clone_apply_transform (ClutterActor *self, CoglMatrix *matrix)
{
ClutterClonePrivate *priv = CLUTTER_CLONE (self)->priv;
ClutterGeometry geom;
ClutterGeometry source_geom;
gfloat x_scale;
gfloat y_scale;
/* First chain up and apply all the standard ClutterActor
* transformations... */
CLUTTER_ACTOR_CLASS (clutter_clone_parent_class)->apply_transform (self,
matrix);
/* if we don't have a source, nothing else to do */
if (priv->clone_source == NULL)
return;
/* get our allocated size */
clutter_actor_get_allocation_geometry (self, &geom);
/* and get the allocated size of the source */
clutter_actor_get_allocation_geometry (priv->clone_source, &source_geom);
/* We need to scale what the clone-source actor paints to fill our own
* allocation...
*/
x_scale = (gfloat) geom.width / source_geom.width;
y_scale = (gfloat) geom.height / source_geom.height;
cogl_matrix_scale (matrix, x_scale, y_scale, x_scale);
}
static void
clutter_clone_paint (ClutterActor *actor)
{
ClutterClone *self = CLUTTER_CLONE (actor);
ClutterClonePrivate *priv = self->priv;
gboolean was_unmapped = FALSE;
if (priv->clone_source == NULL)
return;
CLUTTER_NOTE (PAINT, "painting clone actor '%s'",
_clutter_actor_get_debug_name (actor));
/* The final bits of magic:
* - We need to override the paint opacity of the actor with our own
* opacity.
* - We need to inform the actor that it's in a clone paint (for the function
* clutter_actor_is_in_clone_paint())
* - We need to stop clutter_actor_paint applying the model view matrix of
* the clone source actor.
*/
_clutter_actor_set_in_clone_paint (priv->clone_source, TRUE);
_clutter_actor_set_opacity_override (priv->clone_source,
clutter_actor_get_paint_opacity (actor));
_clutter_actor_set_enable_model_view_transform (priv->clone_source, FALSE);
if (!CLUTTER_ACTOR_IS_MAPPED (priv->clone_source))
{
_clutter_actor_set_enable_paint_unmapped (priv->clone_source, TRUE);
was_unmapped = TRUE;
}
_clutter_actor_push_clone_paint ();
clutter_actor_paint (priv->clone_source);
_clutter_actor_pop_clone_paint ();
if (was_unmapped)
_clutter_actor_set_enable_paint_unmapped (priv->clone_source, FALSE);
_clutter_actor_set_enable_model_view_transform (priv->clone_source, TRUE);
_clutter_actor_set_opacity_override (priv->clone_source, -1);
_clutter_actor_set_in_clone_paint (priv->clone_source, FALSE);
}
static gboolean
clutter_clone_get_paint_volume (ClutterActor *actor,
ClutterPaintVolume *volume)
{
ClutterClonePrivate *priv = CLUTTER_CLONE (actor)->priv;
const ClutterPaintVolume *source_volume;
/* if the source is not set the paint volume is defined to be empty */
if (priv->clone_source == NULL)
return TRUE;
/* query the volume of the source actor and simply masquarade it as
* the clones volume... */
source_volume = clutter_actor_get_paint_volume (priv->clone_source);
if (source_volume == NULL)
return FALSE;
_clutter_paint_volume_set_from_volume (volume, source_volume);
_clutter_paint_volume_set_reference_actor (volume, actor);
return TRUE;
}
clutter-actor: Add a 'has_overlaps' virtual This adds a virtual to ClutterActor so that an actor subclass can report whether it has overlapping primitives. ClutterActor uses this to determine whether it needs to use ClutterFlattenEffect to implement the opacity property. The default implementation of the virtual returns TRUE which means that most actors will end up being redirected offscreen when the opacity != 255. ClutterTexture and ClutterRectangle override this to return FALSE because they should never need to be redirected. ClutterClone overrides it to divert to the source. The values for the ClutterOffscreenRedirect enum have changed to: AUTOMATIC_FOR_OPACITY The actor will only be redirected if has_overlaps returns TRUE and the opacity is < 255 ALWAYS_FOR_OPACITY The actor will always be redirected if the opacity < 255 regardless of the return value of has_overlaps ALWAYS The actor will always be redirected offscreen. This means that the property can't be used to prevent the actor from being redirected but only to increase the likelihood that it will be redirected. ClutterActor now adds and removes the flatten effect depending on whether flattening is needed directly in clutter_actor_paint(). There are new internal versions of add/remove_effect that don't queue a redraw. This means that ClutterFlattenEffect is now just a no-op subclass of ClutterOffscreen. It is only needed because ClutterOffscreen is abstract. Removing the effect also makes it so that the cached image will be freed as soon as an actor is repainted without being flattened.
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static gboolean
clutter_clone_has_overlaps (ClutterActor *actor)
clutter-actor: Add a 'has_overlaps' virtual This adds a virtual to ClutterActor so that an actor subclass can report whether it has overlapping primitives. ClutterActor uses this to determine whether it needs to use ClutterFlattenEffect to implement the opacity property. The default implementation of the virtual returns TRUE which means that most actors will end up being redirected offscreen when the opacity != 255. ClutterTexture and ClutterRectangle override this to return FALSE because they should never need to be redirected. ClutterClone overrides it to divert to the source. The values for the ClutterOffscreenRedirect enum have changed to: AUTOMATIC_FOR_OPACITY The actor will only be redirected if has_overlaps returns TRUE and the opacity is < 255 ALWAYS_FOR_OPACITY The actor will always be redirected if the opacity < 255 regardless of the return value of has_overlaps ALWAYS The actor will always be redirected offscreen. This means that the property can't be used to prevent the actor from being redirected but only to increase the likelihood that it will be redirected. ClutterActor now adds and removes the flatten effect depending on whether flattening is needed directly in clutter_actor_paint(). There are new internal versions of add/remove_effect that don't queue a redraw. This means that ClutterFlattenEffect is now just a no-op subclass of ClutterOffscreen. It is only needed because ClutterOffscreen is abstract. Removing the effect also makes it so that the cached image will be freed as soon as an actor is repainted without being flattened.
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{
ClutterClonePrivate *priv = CLUTTER_CLONE (actor)->priv;
clutter-actor: Add a 'has_overlaps' virtual This adds a virtual to ClutterActor so that an actor subclass can report whether it has overlapping primitives. ClutterActor uses this to determine whether it needs to use ClutterFlattenEffect to implement the opacity property. The default implementation of the virtual returns TRUE which means that most actors will end up being redirected offscreen when the opacity != 255. ClutterTexture and ClutterRectangle override this to return FALSE because they should never need to be redirected. ClutterClone overrides it to divert to the source. The values for the ClutterOffscreenRedirect enum have changed to: AUTOMATIC_FOR_OPACITY The actor will only be redirected if has_overlaps returns TRUE and the opacity is < 255 ALWAYS_FOR_OPACITY The actor will always be redirected if the opacity < 255 regardless of the return value of has_overlaps ALWAYS The actor will always be redirected offscreen. This means that the property can't be used to prevent the actor from being redirected but only to increase the likelihood that it will be redirected. ClutterActor now adds and removes the flatten effect depending on whether flattening is needed directly in clutter_actor_paint(). There are new internal versions of add/remove_effect that don't queue a redraw. This means that ClutterFlattenEffect is now just a no-op subclass of ClutterOffscreen. It is only needed because ClutterOffscreen is abstract. Removing the effect also makes it so that the cached image will be freed as soon as an actor is repainted without being flattened.
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/* The clone has overlaps iff the source has overlaps */
if (priv->clone_source == NULL)
return FALSE;
return clutter_actor_has_overlaps (priv->clone_source);
}
static void
clutter_clone_allocate (ClutterActor *self,
const ClutterActorBox *box,
ClutterAllocationFlags flags)
{
ClutterClonePrivate *priv = CLUTTER_CLONE (self)->priv;
ClutterActorClass *parent_class;
/* chain up */
parent_class = CLUTTER_ACTOR_CLASS (clutter_clone_parent_class);
parent_class->allocate (self, box, flags);
if (priv->clone_source == NULL)
return;
#if 0
/* XXX - this is wrong: ClutterClone cannot clone unparented
* actors, as it will break all invariants
*/
/* we act like a "foster parent" for the source we are cloning;
* if the source has not been parented we have to force an
* allocation on it, so that we can paint it correctly from
* within our paint() implementation. since the actor does not
* have a parent, and thus it won't be painted by the usual
* paint cycle, we can safely give it as much size as it requires
*/
if (clutter_actor_get_parent (priv->clone_source) == NULL)
clutter_actor_allocate_preferred_size (priv->clone_source, flags);
#endif
}
static void
clutter_clone_set_property (GObject *gobject,
guint prop_id,
const GValue *value,
GParamSpec *pspec)
{
ClutterClone *self = CLUTTER_CLONE (gobject);
switch (prop_id)
{
case PROP_SOURCE:
clutter_clone_set_source (self, g_value_get_object (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
break;
}
}
static void
clutter_clone_get_property (GObject *gobject,
guint prop_id,
GValue *value,
GParamSpec *pspec)
{
ClutterClonePrivate *priv = CLUTTER_CLONE (gobject)->priv;
switch (prop_id)
{
case PROP_SOURCE:
g_value_set_object (value, priv->clone_source);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
break;
}
}
static void
clutter_clone_dispose (GObject *gobject)
{
clutter_clone_set_source_internal (CLUTTER_CLONE (gobject), NULL);
G_OBJECT_CLASS (clutter_clone_parent_class)->dispose (gobject);
}
static void
clutter_clone_class_init (ClutterCloneClass *klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
ClutterActorClass *actor_class = CLUTTER_ACTOR_CLASS (klass);
g_type_class_add_private (gobject_class, sizeof (ClutterClonePrivate));
actor_class->apply_transform = clutter_clone_apply_transform;
actor_class->paint = clutter_clone_paint;
actor_class->get_paint_volume = clutter_clone_get_paint_volume;
actor_class->get_preferred_width = clutter_clone_get_preferred_width;
actor_class->get_preferred_height = clutter_clone_get_preferred_height;
actor_class->allocate = clutter_clone_allocate;
actor_class->has_overlaps = clutter_clone_has_overlaps;
gobject_class->dispose = clutter_clone_dispose;
gobject_class->set_property = clutter_clone_set_property;
gobject_class->get_property = clutter_clone_get_property;
/**
* ClutterClone:source:
*
* This property specifies the source actor being cloned.
*
* Since: 1.0
*/
obj_props[PROP_SOURCE] =
g_param_spec_object ("source",
P_("Source"),
P_("Specifies the actor to be cloned"),
CLUTTER_TYPE_ACTOR,
G_PARAM_CONSTRUCT |
CLUTTER_PARAM_READWRITE);
g_object_class_install_properties (gobject_class, PROP_LAST, obj_props);
}
static void
clutter_clone_init (ClutterClone *self)
{
ClutterClonePrivate *priv;
self->priv = priv = CLUTTER_CLONE_GET_PRIVATE (self);
priv->clone_source = NULL;
}
/**
* clutter_clone_new:
* @source: a #ClutterActor, or %NULL
*
* Creates a new #ClutterActor which clones @source/
*
* Return value: the newly created #ClutterClone
*
* Since: 1.0
*/
ClutterActor *
clutter_clone_new (ClutterActor *source)
{
return g_object_new (CLUTTER_TYPE_CLONE, "source", source, NULL);
}
static void
clone_source_queue_redraw_cb (ClutterActor *source,
ClutterActor *origin,
ClutterClone *self)
{
clutter_actor_queue_redraw (CLUTTER_ACTOR (self));
}
static void
clone_source_queue_relayout_cb (ClutterActor *source,
ClutterClone *self)
{
clutter_actor_queue_relayout (CLUTTER_ACTOR (self));
}
static void
clutter_clone_set_source_internal (ClutterClone *self,
ClutterActor *source)
{
ClutterClonePrivate *priv = self->priv;
if (priv->clone_source != NULL)
{
g_signal_handlers_disconnect_by_func (priv->clone_source,
G_CALLBACK (clone_source_queue_redraw_cb),
self);
g_signal_handlers_disconnect_by_func (priv->clone_source,
G_CALLBACK (clone_source_queue_relayout_cb),
self);
g_object_unref (priv->clone_source);
priv->clone_source = NULL;
}
if (source != NULL)
{
priv->clone_source = g_object_ref (source);
g_signal_connect (priv->clone_source, "queue-redraw",
G_CALLBACK (clone_source_queue_redraw_cb), self);
g_signal_connect (priv->clone_source, "queue-relayout",
G_CALLBACK (clone_source_queue_relayout_cb), self);
}
g_object_notify_by_pspec (G_OBJECT (self), obj_props[PROP_SOURCE]);
clutter_actor_queue_relayout (CLUTTER_ACTOR (self));
}
/**
* clutter_clone_set_source:
* @self: a #ClutterClone
* @source: (allow-none): a #ClutterActor, or %NULL
*
* Sets @source as the source actor to be cloned by @self.
*
* Since: 1.0
*/
void
clutter_clone_set_source (ClutterClone *self,
ClutterActor *source)
{
g_return_if_fail (CLUTTER_IS_CLONE (self));
g_return_if_fail (source == NULL || CLUTTER_IS_ACTOR (source));
clutter_clone_set_source_internal (self, source);
clutter_actor_queue_relayout (CLUTTER_ACTOR (self));
}
/**
* clutter_clone_get_source:
* @self: a #ClutterClone
*
* Retrieves the source #ClutterActor being cloned by @self.
*
* Return value: (transfer none): the actor source for the clone
*
* Since: 1.0
*/
ClutterActor *
clutter_clone_get_source (ClutterClone *self)
{
g_return_val_if_fail (CLUTTER_IS_CLONE (self), NULL);
return self->priv->clone_source;
}