mutter/doc/cookbook/examples/effects-custom-deform.c
Elliot Smith 74de3cfdf3 docs: Add effects chapter, with introduction and first recipe
Add an effects chapter which gives a broad overview of
the abstract classes in the effects API, plus a short
example of how to apply one of the stock Clutter
effects (ClutterColorizeEffect).

The recipe explains how to create a custom ClutterDeformEffect
to produce a page fold (code based on ClutterPageTurnEffect).

The example code includes the effect class plus a small
application to apply it to a texture.
2011-02-21 16:44:09 +00:00

120 lines
3.3 KiB
C

/* Example of using a custom CbPageFoldEffect to do
* an animated fold of a texture containing an image
*
* Pass the full path to the image on the command line;
* click on the texture to trigger the folding animation
*/
#include <stdlib.h>
#include <clutter/clutter.h>
#include "cb-page-fold-effect.h"
static const ClutterColor stage_color = { 0x33, 0x33, 0x55, 0xff };
static gboolean
button_pressed_cb (ClutterActor *actor,
ClutterEvent *event,
gpointer user_data)
{
ClutterState *transitions = CLUTTER_STATE (user_data);
if (g_strcmp0 (clutter_state_get_state (transitions), "folded") == 0)
clutter_state_set_state (transitions, "unfolded");
else
clutter_state_set_state (transitions, "folded");
return TRUE;
}
int
main (int argc,
char *argv[])
{
ClutterActor *stage;
ClutterActor *texture;
ClutterEffect *effect;
ClutterState *transitions;
GError *error = NULL;
gchar *filename;
if (argc < 2)
{
g_print ("Usage: %s <path to image file>\n", argv[0]);
return EXIT_FAILURE;
}
filename = argv[1];
clutter_init (&argc, &argv);
stage = clutter_stage_new ();
clutter_actor_set_size (stage, 400, 300);
clutter_stage_set_color (CLUTTER_STAGE (stage), &stage_color);
g_signal_connect (stage, "destroy", G_CALLBACK (clutter_main_quit), NULL);
texture = clutter_texture_new ();
clutter_texture_set_keep_aspect_ratio (CLUTTER_TEXTURE (texture), TRUE);
clutter_actor_set_width (texture, 400);
clutter_actor_set_reactive (texture, TRUE);
clutter_texture_set_from_file (CLUTTER_TEXTURE (texture),
filename,
&error);
if (error != NULL)
{
g_critical ("Error loading texture from file %s; error was:\n%s",
filename,
error->message);
return EXIT_FAILURE;
}
/* create the page fold effect instance with destination fold angle
* of 180 degrees and starting period of 0 (no folding)
*/
effect = cb_page_fold_effect_new (180.0, 0.0);
/* add the effect to the texture actor */
clutter_actor_add_effect (texture, effect);
clutter_container_add_actor (CLUTTER_CONTAINER (stage), texture);
/* animation for the period property of the effect,
* to animate its value between 0.0 and 1.0 and back
*/
transitions = clutter_state_new ();
clutter_state_set_duration (transitions, NULL, NULL, 500);
clutter_state_set_duration (transitions,
"partially-folded",
"folded",
375);
clutter_state_set (transitions, NULL, "folded",
effect, "period", CLUTTER_LINEAR, 1.0,
NULL);
clutter_state_set (transitions, NULL, "partially-folded",
effect, "period", CLUTTER_LINEAR, 0.25,
NULL);
clutter_state_set (transitions, NULL, "unfolded",
effect, "period", CLUTTER_LINEAR, 0.0,
NULL);
clutter_state_warp_to_state (transitions, "partially-folded");
g_signal_connect (texture,
"button-press-event",
G_CALLBACK (button_pressed_cb),
transitions);
clutter_actor_show (stage);
clutter_main ();
g_object_unref (transitions);
return EXIT_SUCCESS;
}