26aa4b5290
A lot of the example code in the cookbook and the API reference still uses the default stage — sometimes as if it were a non-default one, which once again demonstrates how the default stage was a flawed concept that just confused people.
156 lines
3.8 KiB
C
156 lines
3.8 KiB
C
/* Simple rectangle drawing using button and pointer events;
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* click, drag and release a mouse button to draw a rectangle
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*/
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#include <stdlib.h>
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#include <clutter/clutter.h>
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static const ClutterColor stage_color = { 0x33, 0x33, 0x55, 0xff };
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static const ClutterColor lasso_color = { 0xaa, 0xaa, 0xaa, 0x33 };
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typedef struct
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{
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ClutterActor *actor;
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gfloat x;
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gfloat y;
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} Lasso;
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static guint
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random_color_component ()
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{
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return (guint) (155 + (100.0 * rand () / (RAND_MAX + 1.0)));
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}
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static gboolean
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button_pressed_cb (ClutterActor *actor,
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ClutterEvent *event,
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gpointer user_data)
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{
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Lasso *lasso = (Lasso *) user_data;
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/* start drawing the lasso actor */
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lasso->actor = clutter_rectangle_new_with_color (&lasso_color);
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/* store lasso's start coordinates */
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clutter_event_get_coords (event, &(lasso->x), &(lasso->y));
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clutter_container_add_actor (CLUTTER_CONTAINER (actor), lasso->actor);
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return TRUE;
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}
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static gboolean
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button_released_cb (ClutterActor *stage,
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ClutterEvent *event,
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gpointer user_data)
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{
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Lasso *lasso = (Lasso *) user_data;
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ClutterActor *rectangle;
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ClutterColor *random_color;
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gfloat x;
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gfloat y;
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gfloat width;
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gfloat height;
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if (lasso->actor == NULL)
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return TRUE;
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/* create a new rectangle */
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random_color = clutter_color_new (random_color_component (),
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random_color_component (),
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random_color_component (),
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random_color_component ());
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rectangle = clutter_rectangle_new_with_color (random_color);
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/* set the rectangle to the same size and shape as the lasso */
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clutter_actor_get_position (lasso->actor, &x, &y);
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clutter_actor_get_size (lasso->actor, &width, &height);
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clutter_actor_set_position (rectangle, x, y);
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clutter_actor_set_size (rectangle, width, height);
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clutter_container_add_actor (CLUTTER_CONTAINER (stage), rectangle);
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/* clear up the lasso actor */
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clutter_actor_destroy (lasso->actor);
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lasso->actor = NULL;
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clutter_actor_queue_redraw (stage);
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return TRUE;
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}
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static gboolean
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pointer_motion_cb (ClutterActor *stage,
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ClutterEvent *event,
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gpointer user_data)
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{
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gfloat pointer_x;
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gfloat pointer_y;
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gfloat new_x;
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gfloat new_y;
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gfloat width;
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gfloat height;
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Lasso *lasso = (Lasso *) user_data;
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if (lasso->actor == NULL)
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return TRUE;
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/* redraw the lasso actor */
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clutter_event_get_coords (event, &pointer_x, &pointer_y);
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new_x = MIN (pointer_x, lasso->x);
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new_y = MIN (pointer_y, lasso->y);
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width = MAX (pointer_x, lasso->x) - new_x;
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height = MAX (pointer_y, lasso->y) - new_y;
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clutter_actor_set_position (lasso->actor, new_x, new_y);
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clutter_actor_set_size (lasso->actor, width, height);
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return TRUE;
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}
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int
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main (int argc,
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char *argv[])
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{
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Lasso *lasso = g_new0 (Lasso, 1);
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ClutterActor *stage;
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/* seed random number generator */
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srand ((unsigned int) time (NULL));
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if (clutter_init (&argc, &argv) != CLUTTER_INIT_SUCCESS)
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return 1;
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stage = clutter_stage_new ();
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clutter_actor_set_size (stage, 320, 240);
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clutter_stage_set_color (CLUTTER_STAGE (stage), &stage_color);
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g_signal_connect (stage, "destroy", G_CALLBACK (clutter_main_quit), NULL);
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g_signal_connect (stage,
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"button-press-event",
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G_CALLBACK (button_pressed_cb),
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lasso);
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g_signal_connect (stage,
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"button-release-event",
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G_CALLBACK (button_released_cb),
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lasso);
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g_signal_connect (stage,
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"motion-event",
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G_CALLBACK (pointer_motion_cb),
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lasso);
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clutter_actor_show (stage);
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clutter_main ();
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g_free (lasso);
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return EXIT_SUCCESS;
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}
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