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For example:</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>To move user interface elements in response to user input
(e.g. keyboard control of a character in a game).</p></li><li class="listitem"><p>To move a group of actors "off stage" to make way
for another group of actors (e.g. paging through
thumbnails in a photo viewer).</p></li><li class="listitem"><p>To move an actor to a different position in the
interface (e.g. moving an icon for a trashed file into
a wastebin).</p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp62293472"></a>7.2. Solutions</h3></div></div></div><p>Animate the actors movement on one or more axes
(<code class="varname">x</code>, <code class="varname">y</code>,
<code class="varname">z/depth</code>) using one or more of the approaches
available in the Clutter API (implicit animations,
<span class="type">ClutterState</span>, <span class="type">ClutterAnimator</span>).</p><div class="section"><div class="titlepage"><div><div><h4 class="title"><a name="idp62296528"></a>7.2.1. Solution 1: Implicit animations</h4></div></div></div><p>This works well for simple movement of a single actor to
a single set of coordinates. Here is an example of how to animate
movement of a <span class="type">ClutterActor</span> <code class="varname">actor</code>
to position <code class="code">100.0</code> on <code class="varname">x</code> axis:</p><div class="informalexample"><pre class="programlisting">clutter_actor_animate (actor, CLUTTER_LINEAR, 500,
"x", 100.0,
NULL);</pre></div><p>See <a class="link" href="animations-moving.html#animations-moving-example-1" title="Example 5.8. Simple movement using implicit animations">this
example</a> which demonstrates movement in each axis,
in response to (mouse) button presses.</p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a name="idp62301664"></a>7.2.2. Solution 2: <span class="type">ClutterState</span></h4></div></div></div><p>This suits simple, repeated movement of one or more actors
between sets of coordinates. Here is an example of how to
create two states for a <span class="type">ClutterState</span> instance to
move two actors, <code class="varname">actor1</code> and
<code class="varname">actor2</code>:</p><div class="informalexample"><pre class="programlisting">ClutterState *transitions = clutter_state_new ();
/* all state transitions take 250ms */
clutter_state_set_duration (transitions, NULL, NULL, 250);
/* create a state called move-down which moves both actors to y = 200.0 */
clutter_state_set (transitions, NULL, "move-down",
actor1, "y", CLUTTER_EASE_OUT_CUBIC, 200.0,
actor2, "y", CLUTTER_EASE_OUT_CUBIC, 200.0,
NULL);
/* create a state called move-up which moves both actors to y = 0.0 */
clutter_state_set (transitions, NULL, "move-up",
actor1, "y", CLUTTER_EASE_OUT_CUBIC, 0.0,
actor2, "y", CLUTTER_EASE_OUT_CUBIC, 0.0,
NULL);
/* move the actors by setting the state */
clutter_state_set (transitions, "move-down");</pre></div><p>This <a class="link" href="animations-moving.html#animations-moving-example-2" title="Example 5.9. Using ClutterState to repeatedly move (and scale) two actors">full
example</a> shows how to move and simultaneously
scale two actors. When a button is pressed on one actor, it is
moved and scaled to occupy the right-hand side of the stage;
the other actor is simultaneously moved back to the left-hand
side of the stage and scaled down.</p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a name="idp62307536"></a>7.2.3. Solution 3: <span class="type">ClutterAnimator</span></h4></div></div></div><p>This is a good way to implement complex movement of
one or more actors between sets of coordinates.</p><div class="informalexample"><pre class="programlisting">ClutterAnimator *animator = clutter_animator_new ();
/* the animation takes 500ms */
clutter_animator_set_duration (animator, 500);
/* at the start of the animation, actor should be at 0.0,0.0;
* half-way through, at 100.0,100.0;
* by the end, actor should be at 150.0,200.0;
* note that you can set different easing modes for each
* part of the animation and for each property at each key
*/
clutter_animator_set (animator,
/* keys for the start of the animation */
actor, "x", CLUTTER_LINEAR, 0.0, 0.0,
actor, "y", CLUTTER_LINEAR, 0.0, 0.0,
/* keys for half-way through the animation */
actor, "x", CLUTTER_EASE_OUT_CUBIC, 0.5, 100.0,
actor, "y", CLUTTER_EASE_IN_CUBIC, 0.5, 100.0,
/* keys for the end of the animation */
actor, "x", CLUTTER_EASE_OUT_EXPO, 1.0, 150.0,
actor, "y", CLUTTER_EASE_OUT_CUBIC, 1.0, 200.0,
NULL);
/* run the animation */
clutter_animator_start (animator);</pre></div><p>The <a class="link" href="animations-moving.html#animations-moving-example-3" title="Example 5.10. Using ClutterAnimator to randomly move three actors along the x axis">full
example</a> demonstrates how <span class="type">ClutterAnimator</span>
can be used to programmatically animate multiple actors: in this
case, to simultaneously move three actors to random positions
along the <code class="varname">x</code> axis. Synchronising the
movement of three actors simultaneously using implicit
animations would be possible but awkward;
<span class="type">ClutterState</span> might be another option,
but it wasn't really designed for this case: there are no persistent
states to transition between, as the actor positions are
generated on each key press.</p><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>If you want to apply the same movement to a group of
actors, rather than different movements for each actor,
it's often better to put the actors into a container
of some kind and move that instead of moving the actors
individually.</p></div></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp62315136"></a>7.3. Discussion</h3></div></div></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a name="idp62315776"></a>7.3.1. Movement can take an actor "outside" its container</h4></div></div></div><p>Actor movement in the <code class="varname">x</code> and
<code class="varname">y</code> axes is relative to the actor's parent
container. There is nothing to stop you animating an actor
until it falls outside the bounds of its container. This
could result in the actor moving "off" the interface; though it's
worth remembering that the actor is not unparented or destroyed
if this happens.</p><p>To ensure that an actor remains visible, its position
should remain within the visible area of the container. In practice,
this means either anywhere in the container, if no clip area
has been set; or within the container's clip area, if set.</p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a name="idp62318720"></a>7.3.2. Anchor points can affect movement</h4></div></div></div><p>An actor's anchor point is defined as an <code class="code">x,y</code>
coordinate relative to the top-left of the actor. The default
anchor point for an actor is in its top-left
corner. However, it is possible to set this to some other
coordinate, relative to the actor's top-left corner,
using the <code class="function">clutter_anchor_set_anchor_point()</code>
function.</p><p>For example:</p><div class="informalexample"><pre class="programlisting">/* set the actor's size to 100px x 100px */
clutter_actor_set_size (actor, 100, 100);
/* set an anchor point half-way along the top of the actor */
clutter_actor_set_anchor_point (actor, 50.0, 0.0);</pre></div><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>In GL terms, the anchor point of an actor is the equivalent
of applying an additional transformation of <code class="code">-x, -y</code> to
the actor's modelview. If the anchor point is <code class="code">0, 0</code>,
i.e. the top-left corner, then the transformation will leave the
actor in the same place.</p><p>It is important to note that the anchor point will affect the
position in which an actor is painted, but will not change the
position or size that its parent allocated for it.</p><p>Finally, the anchor point will affect the other transformations
that can be applied to an actor: scaling and rotating.</p></div><p>A positive anchor point within the width/height bounds of the
actor is inside the actor. An anchor point outside these bounds
is outside the actor. You can also set a negative
<code class="varname">x</code> or <code class="varname">y</code> value for
the anchor point, which will again place the point outside
the actor's bounds.</p><p>This is important with respect to moving an actor, because
you are actually moving the anchor point and "dragging" the
actor along with it.</p><p>For example: you have an actor with width 50px, and you
set its <code class="varname">anchor-x</code> property to <code class="code">25.0</code>.
If you move that actor on the <code class="varname">x</code> axis, you are
effectively moving a point half-way across the top of the
actor along the <code class="varname">x</code> axis (which in turn moves the
actor).</p><p>Similarly, you could set the same actor's
<code class="varname">anchor-x</code> to <code class="code">-25.0</code>. If you then
moved the actor along the <code class="varname">x</code> axis, you would
effectively be moving the point 25px left of the top of the actor
along that axis.</p><p>The video below demonstrates the effect on movement of shifting
the anchor point on the <code class="varname">x</code> axis. The
<span class="emphasis"><em>red</em></span> rectangle has <code class="varname">anchor-x</code>
set to <code class="code">25.0</code>; the <span class="emphasis"><em>green</em></span> rectangle has
<code class="varname">anchor-x</code> set to <code class="code">0.0</code> (the default); the
<span class="emphasis"><em>blue</em></span> rectangle has <code class="varname">anchor-x</code>
set to <code class="code">-25.0</code>.</p><p><video controls="controls" src="videos/animations-moving-anchors.ogv"><a href="videos/animations-moving-anchors.ogv"></a></video></p><p> A <span class="type">ClutterAnimator</span> is
used to move each of the rectangles to <code class="code">x = 225.0</code>.
Although the three rectangles move to the same position on the
<code class="varname">x</code> axis, it's actually the anchor points
which are at the same position. These all align on the
<code class="varname">x</code> axis with the left-hand edge of the green
rectangle.</p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a name="idp62340240"></a>7.3.3. Actors can move in the <code class="varname">z</code> axis</h4></div></div></div><p>The examples so far have shown how to move actors in
the <code class="varname">x</code> and <code class="varname">y</code> axes; but it
is also possible to move actors in the <code class="varname">z</code>
axis (i.e. move them closer or further away from the view point).
This lets you move actors under/over each other.</p><p>To move an actor in the <code class="varname">z</code> axis, animate
its <code class="varname">depth</code> property. Animating to a negative
depth moves the actor away from the view point; animating to a
positive depth moves the actor towards the view point.</p><p>Changing the depth of an actor also causes perspective
effects: the actor gets smaller and converges on the center
of the stage as it gets further from the view point, and
gets larger and diverges from the center of the stage as it gets
closer. This results in an apparent (but not actual) change in
the <code class="code">x,y</code> position and scale of the actor.</p><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>Animating the depth of an actor is slightly different
from animating its x and y coordinates, as depth is relative
to the whole stage, not just the parent container of the
actor. This means that perspective effects are with
respect to the whole stage: so as an actor's depth
moves below <code class="code">0.0</code>, it converges on the center
of the stage, and may even apparently move outside its
container (if the container stays at the same depth).</p></div><p>The video below demonstrates the effect of animating
the depth of four actors to a value of <code class="code">-15000.0</code>.
Note how the actors converge on the center of the stage,
as well as appearing to change position and scale; also note
that they appear to move outside the bounds of their parent containers
(the four yellow <span class="type">ClutterBoxes</span>).</p><p><video controls="controls" src="videos/animations-moving-depth.ogv"><a href="videos/animations-moving-depth.ogv"></a></video></p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a name="idp62351040"></a>7.3.4. Movement is affected by constraints</h4></div></div></div><p>An actor can have its x,y position constrained by
the position of other actors through <span class="type">ClutterBindConstraints</span>.
This can affect movement in two ways:</p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>If an actor has its <code class="varname">x</code> and/or
<code class="varname">y</code> properties
bound or aligned to another actor's, you can't animate
those properties.</p><p>In effect this means that the bound actor can't be
moved on a bound axis directly, but can only be moved by
animating the constraint's properties.</p></li><li class="listitem"><p>If you move an actor which has other actors bound to
it, the bound actors will also move. For example, if
the actor has several other actors whose <code class="varname">x</code>
properties are bound to its <code class="varname">x</code> property,
moving the actor on the <code class="varname">x</code> axis will also
move the bound actors on that axis.</p><p>Similarly, if some actor is the source for
alignment constraints on other actors, moving the source
will cause those other actors to move, so that they remain in
alignment with it.</p></li></ol></div><p>For example, consider two actors bound by constraints
as follows:</p><div class="informalexample"><pre class="programlisting">/* the source actor for the constraint */
ClutterActor *source;
/* the actor bound by the constraint */
ClutterActor *target;
/* a constraint to be added to target */
ClutterConstraint *constraint;
/* ...initialize actors etc... */
/* create a constraint for binding the x position of some actor to the
* x position of source
*/
constraint = clutter_bind_constraint_new (source, CLUTTER_BIND_X, 0.0);
/* add the constraint to target with a name */
clutter_actor_add_constraint_with_name (target, "bind-x", constraint);</pre></div><p>Animating <code class="varname">source</code> on the <code class="varname">x</code>
axis also animates <code class="varname">target</code> on the same axis:</p><div class="informalexample"><pre class="programlisting">clutter_actor_animate (source, CLUTTER_LINEAR, 500,
"x", 250.0,
NULL);</pre></div><p>...while this has no effect, as it would violate
<code class="varname">constraint</code> (it's best not to animate
<code class="varname">target's</code> <code class="varname">x</code> property
directly):</p><div class="informalexample"><pre class="programlisting">clutter_actor_animate (target, CLUTTER_LINEAR, 500,
"x", 250.0,
NULL);</pre></div><p>But the constraint's properties can be animated, to change
how <code class="varname">source</code> and <code class="varname">target</code>
are bound; which in turn moves <code class="varname">target</code>:</p><div class="informalexample"><pre class="programlisting">clutter_actor_animate (target, CLUTTER_LINEAR, 500,
"@constraints.bind-x.offset", 250.0,
NULL);</pre></div><p>Note the <code class="code">@constraints.<constraint name>.<constraint property></code>
syntax (which is why we needed to use
<code class="function">clutter_actor_add_constraint_with_name()</code>,
so that the constraint can be accessed through the actor).
We are still animating <code class="varname">target</code>, but really
we're indirectly animating a property of one of its constraints.</p><p>Another alternative would be to directly animate
the constraint's properties through <span class="type">ClutterState</span>
or <span class="type">ClutterAnimator</span>, rather than using
pseudo-properties on the actor animation:</p><div class="informalexample"><pre class="programlisting">ClutterAnimator *animator = clutter_animator_new ();
clutter_animator_set_duration (animator, 500);
clutter_animator_set (animator,
constraint, "offset", CLUTTER_LINEAR, 0.0, 0.0,
constraint, "offset", CLUTTER_LINEAR, 1.0, 250.0,
NULL);
clutter_animator_start (animator);</pre></div><p>This could be useful if you need to animate
multiple constraints between multiple values simultaneously.</p></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="animations-moving-examples"></a>7.4. Full examples</h3></div></div></div><div class="example"><a name="animations-moving-example-1"></a><p class="title"><b>Example 5.8. Simple movement using implicit animations</b></p><div class="example-contents"><pre class="programlisting">#include <stdlib.h>
#include <clutter/clutter.h>
typedef struct
{
gchar *axis;
gfloat target;
} AnimationSpec;
static gboolean
button_pressed_cb (ClutterActor *actor,
ClutterEvent *event,
gpointer user_data)
{
AnimationSpec *animation_spec = user_data;
ClutterTransition *transition;
if (clutter_actor_get_transition (actor, animation_spec->axis) != NULL)
return TRUE;
clutter_actor_save_easing_state (actor);
clutter_actor_set_easing_duration (actor, 500);
g_object_set (actor, animation_spec->axis, animation_spec->target, NULL);
transition = clutter_actor_get_transition (actor, animation_spec->axis);
clutter_timeline_set_auto_reverse (CLUTTER_TIMELINE (transition), TRUE);
clutter_timeline_set_repeat_count (CLUTTER_TIMELINE (transition), 1);
clutter_actor_restore_easing_state (actor);
return TRUE;
}
int
main (int argc,
char *argv[])
{
ClutterActor *stage;
ClutterActor *rectangle1;
ClutterActor *rectangle2;
ClutterActor *rectangle3;
AnimationSpec x_move = { "x", 50.0 };
AnimationSpec y_move = { "y", 400.0 };
AnimationSpec z_move = { "depth", -1000.0 };
if (clutter_init (&argc, &argv) != CLUTTER_INIT_SUCCESS)
return 1;
stage = clutter_stage_new ();
clutter_actor_set_size (stage, 500, 500);
clutter_stage_set_color (CLUTTER_STAGE (stage), CLUTTER_COLOR_Aluminium2);
g_signal_connect (stage, "destroy", G_CALLBACK (clutter_main_quit), NULL);
rectangle1 = clutter_actor_new ();
clutter_actor_set_background_color (rectangle1, CLUTTER_COLOR_ScarletRed);
clutter_actor_set_reactive (rectangle1, TRUE);
clutter_actor_set_size (rectangle1, 50, 50);
clutter_actor_set_position (rectangle1, 400, 400);
clutter_actor_add_child (stage, rectangle1);
rectangle2 = clutter_actor_new ();
clutter_actor_set_background_color (rectangle2, CLUTTER_COLOR_Chameleon);
clutter_actor_set_reactive (rectangle2, TRUE);
clutter_actor_set_size (rectangle2, 50, 50);
clutter_actor_set_position (rectangle2, 50, 50);
clutter_actor_add_child (stage, rectangle2);
rectangle3 = clutter_actor_new ();
clutter_actor_set_background_color (rectangle3, CLUTTER_COLOR_SkyBlue);
clutter_actor_set_reactive (rectangle3, TRUE);
clutter_actor_set_size (rectangle3, 50, 50);
clutter_actor_set_position (rectangle3, 225, 225);
clutter_actor_add_child (stage, rectangle3);
g_signal_connect (rectangle1,
"button-press-event",
G_CALLBACK (button_pressed_cb),
&x_move);
g_signal_connect (rectangle2,
"button-press-event",
G_CALLBACK (button_pressed_cb),
&y_move);
g_signal_connect (rectangle3,
"button-press-event",
G_CALLBACK (button_pressed_cb),
&z_move);
clutter_actor_show (stage);
clutter_main ();
return EXIT_SUCCESS;
}
</pre></div></div><br class="example-break"><div class="example"><a name="animations-moving-example-2"></a><p class="title"><b>Example 5.9. Using <span class="type">ClutterState</span> to repeatedly move
(and scale) two actors</b></p><div class="example-contents"><pre class="programlisting">#include <stdlib.h>
#include <clutter/clutter.h>
static const ClutterColor stage_color = { 0x33, 0x33, 0x55, 0xff };
static const ClutterColor red_color = { 0xff, 0x00, 0x00, 0xff };
static const ClutterColor green_color = { 0x00, 0xff, 0x00, 0xff };
static gboolean
button_pressed_cb (ClutterActor *actor,
ClutterEvent *event,
gpointer user_data)
{
ClutterState *transitions = CLUTTER_STATE (user_data);
/* set the state to the one with a name matching the actor's name */
clutter_state_set_state (transitions, clutter_actor_get_name (actor));
return TRUE;
}
int
main (int argc,
char *argv[])
{
ClutterActor *stage;
ClutterActor *red;
ClutterActor *green;
ClutterState *transitions;
if (clutter_init (&argc, &argv) != CLUTTER_INIT_SUCCESS)
return 1;
stage = clutter_stage_new ();
clutter_actor_set_size (stage, 650, 500);
clutter_stage_set_color (CLUTTER_STAGE (stage), &stage_color);
g_signal_connect (stage, "destroy", G_CALLBACK (clutter_main_quit), NULL);
/* actor names choose the next ClutterState to transition to */
red = clutter_rectangle_new_with_color (&red_color);
clutter_actor_set_reactive (red, TRUE);
clutter_actor_set_name (red, "red");
clutter_actor_set_size (red, 100, 100);
clutter_actor_set_position (red, 50, 50);
green = clutter_rectangle_new_with_color (&green_color);
clutter_actor_set_reactive (green, TRUE);
clutter_actor_set_name (green, "green");
clutter_actor_set_size (green, 100, 100);
clutter_actor_set_position (green, 50, 350);
transitions = clutter_state_new ();
clutter_state_set_duration (transitions, NULL, NULL, 250);
/* state names match actor names */
clutter_state_set (transitions, NULL, "red",
red, "x", CLUTTER_EASE_OUT_CUBIC, 200.0,
red, "y", CLUTTER_EASE_OUT_CUBIC, 50.0,
red, "scale-x", CLUTTER_EASE_OUT_CUBIC, 4.0,
red, "scale-y", CLUTTER_EASE_OUT_CUBIC, 4.0,
green, "x", CLUTTER_EASE_OUT_CUBIC, 50.0,
green, "y", CLUTTER_EASE_OUT_CUBIC, 350.0,
green, "scale-x", CLUTTER_EASE_OUT_CUBIC, 1.0,
green, "scale-y", CLUTTER_EASE_OUT_CUBIC, 1.0,
NULL);
clutter_state_set (transitions, NULL, "green",
green, "x", CLUTTER_EASE_OUT_CUBIC, 200.0,
green, "y", CLUTTER_EASE_OUT_CUBIC, 50.0,
green, "scale-x", CLUTTER_EASE_OUT_CUBIC, 4.0,
green, "scale-y", CLUTTER_EASE_OUT_CUBIC, 4.0,
red, "x", CLUTTER_EASE_OUT_CUBIC, 50.0,
red, "y", CLUTTER_EASE_OUT_CUBIC, 50.0,
red, "scale-x", CLUTTER_EASE_OUT_CUBIC, 1.0,
red, "scale-y", CLUTTER_EASE_OUT_CUBIC, 1.0,
NULL);
g_signal_connect (red,
"button-press-event",
G_CALLBACK (button_pressed_cb),
transitions);
g_signal_connect (green,
"button-press-event",
G_CALLBACK (button_pressed_cb),
transitions);
clutter_container_add (CLUTTER_CONTAINER (stage),
red,
green,
NULL);
clutter_actor_show (stage);
clutter_main ();
g_object_unref (transitions);
return EXIT_SUCCESS;
}
</pre></div></div><br class="example-break"><div class="example"><a name="animations-moving-example-3"></a><p class="title"><b>Example 5.10. Using <span class="type">ClutterAnimator</span> to randomly move
three actors along the <code class="varname">x</code> axis</b></p><div class="example-contents"><pre class="programlisting">#include <stdlib.h>
#include <clutter/clutter.h>
typedef struct
{
ClutterActor *stage;
ClutterActor *group;
ClutterAnimator *animator;
} State;
static const ClutterColor stage_color = { 0x33, 0x33, 0x55, 0xff };
static const ClutterColor red_color = { 0xff, 0x00, 0x00, 0xff };
static const ClutterColor green_color = { 0x00, 0xff, 0x00, 0xff };
static const ClutterColor blue_color = { 0x00, 0x00, 0xff, 0xff };
/* add keys to the animator such that the actor is moved
* to a random x position
*/
static void
add_keys_for_actor (ClutterActor *actor,
ClutterAnimator *animator)
{
gfloat x, end_x;
x = clutter_actor_get_x (actor);
end_x = 50.0;
if (x == 50.0)
end_x = 225.0 + (100.0 * rand () / (RAND_MAX + 1.0));
clutter_animator_set (animator,
actor, "x", CLUTTER_LINEAR, 0.0, x,
actor, "x", CLUTTER_EASE_OUT_CUBIC, 1.0, end_x,
NULL);
}
static gboolean
move_actors (ClutterActor *actor,
ClutterEvent *event,
gpointer user_data)
{
State *state = user_data;
ClutterActor *child;
/* do nothing if the animator is already running */
if (clutter_timeline_is_playing (clutter_animator_get_timeline (state->animator)))
return TRUE;
/* remove all keys from the animator */
clutter_animator_remove_key (state->animator, NULL, NULL, -1);
/* add keys for all actors in the group */
for (child = clutter_actor_get_first_child (state->group);
child != NULL;
child = clutter_actor_get_next_sibling (child))
{
add_keys_for_actor (child, state->animator);
}
/* start the animation */
clutter_animator_start (state->animator);
return TRUE;
}
int
main (int argc,
char *argv[])
{
ClutterActor *red;
ClutterActor *green;
ClutterActor *blue;
State *state = g_new0 (State, 1);
/* seed random number generator */
srand ((unsigned int) time (NULL));
if (clutter_init (&argc, &argv) != CLUTTER_INIT_SUCCESS)
return 1;
state->animator = clutter_animator_new ();
clutter_animator_set_duration (state->animator, 500);
state->stage = clutter_stage_new ();
clutter_actor_set_size (state->stage, 400, 350);
clutter_stage_set_color (CLUTTER_STAGE (state->stage), &stage_color);
g_signal_connect (state->stage,
"destroy",
G_CALLBACK (clutter_main_quit),
NULL);
state->group = clutter_actor_new ();
clutter_actor_add_child (state->stage, state->group);
red = clutter_actor_new ();
clutter_actor_set_background_color (red, &red_color);
clutter_actor_set_size (red, 50, 50);
clutter_actor_set_position (red, 50, 50);
clutter_actor_add_child (state->group, red);
green = clutter_actor_new ();
clutter_actor_set_background_color (green, &green_color);
clutter_actor_set_size (green, 50, 50);
clutter_actor_set_position (green, 50, 150);
clutter_actor_add_child (state->group, green);
blue = clutter_actor_new ();
clutter_actor_set_background_color (blue, &blue_color);
clutter_actor_set_size (blue, 50, 50);
clutter_actor_set_position (blue, 50, 250);
clutter_actor_add_child (state->group, blue);
g_signal_connect (state->stage,
"key-press-event",
G_CALLBACK (move_actors),
state);
clutter_actor_show (state->stage);
clutter_main ();
g_object_unref (state->animator);
g_free (state);
return EXIT_SUCCESS;
}
</pre></div></div><br class="example-break"></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="animations-reuse.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="animations.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="animations-looping.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">6. Reusing a complex animation on different actors </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> 8. Looping an animation</td></tr></table></div></body></html>
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