Add group shrink animation

1 files changed, 47 insertions, 1 deletions

diff --git a/src/animate.c b/src/animate.c
index 8bd09b5..313cfa7 100644
--- a/src/animate.c
+++ b/src/animate.c
@@ -129,8 +129,54 @@ Animation *animation_pulse_create(gint64 duration)
     pulse->type = ANIM_PULSE;
     pulse->before_func = (DrawFunc)pulse_func;
     pulse->duration = duration;
+    return pulse;
+}
+
+static bool shrink_func(Animation *shrink, Layout *layout)
+{
+    g_assert_false(layout->btn->simple);
+    ButtonGroup *group = (gpointer)layout->btn;
+
+    gint64 end = shrink->start + shrink->duration;
+    gint64 now = g_get_monotonic_time();
+
+    if (now > end) {
+        // NOTE: Actually remove the buttons from the group after the animation's end
+        //      This part is quite rough around the edges...
+        if (group->children->next) {
+            g_list_free(g_list_remove_link(group->children, group->children));
+            g_list_free(g_list_remove_link(layout->children, layout->children));
+            layout->width = CAST(layout->children->data, Layout)->width;
+            return true;
+        }
+
+        return false;
+    }
+
+    double t = (double)(now - shrink->start) / (end - shrink->start);
+    double pos = smoothstep(t, 0, 1);
 
-    return (gpointer)pulse;
+    int target_w = CAST(layout->children->data, Layout)->width;
+    int width = layout->width - pos * (layout->width - target_w);
+    layout->width = width;
+
+    for (GList *it = layout->children, *next = it->next; it; it = next, next = it ? it->next : NULL) {
+        Layout *child = it->data;
+        if (child->x + child->width > layout->x + width)
+            layout->children = g_list_delete_link(layout->children, it);
+    }
+
+    return true;
+}
+
+Animation *animation_group_shrink_create(gint64 duration)
+{
+    // Note the 0 initialization
+    Animation *shrink = g_malloc0(sizeof(Animation));
+    shrink->type = ANIM_GROUP_SHRINK;
+    shrink->layout_func = (LayoutFunc)shrink_func;
+    shrink->duration = duration;
+    return shrink;
 }
 
 void animation_destroy(Animation *anim)