Add animation scaffolding

4 files changed, 100 insertions, 0 deletions

diff --git a/src/animate.c b/src/animate.c
new file mode 100644
index 0000000..7b95e9c
--- /dev/null
+++ b/src/animate.c
@@ -0,0 +1,40 @@
+#include <glib.h>
+
+#include "animate.h"
+
+double quadratic_bezier(double x, double a, double b, double c)
+{
+	g_assert(x >= 0 && x <= 1);
+	g_assert(a >= 0 && a <= 1);
+	g_assert(b >= 0 && b <= 1);
+	g_assert(c >= 0 && c <= 1);
+
+	const double t = 1 - x;
+	return a * t * t + 2 * b * t * x + c * x * x;
+}
+
+double cubic_bezier(double x, double a, double b, double c, double d)
+{
+	g_assert(x >= 0 && x <= 1);
+	g_assert(a >= 0 && a <= 1);
+	g_assert(b >= 0 && b <= 1);
+	g_assert(c >= 0 && c <= 1);
+	g_assert(d >= 0 && d <= 1);
+
+	const double t = 1 - x;
+	return a * (t * t * t) + 3 * b * (t * t * x) + 3 * c * (t * x * x) + d * (x * x * x);
+}
+
+Animation *animation_create()
+{
+    Animation *anim = g_malloc0(sizeof(Animation));
+    // TODO
+    return anim;
+}
+
+void animation_destroy(Animation *anim)
+{
+    g_free(anim);
+}
+
+// vim: ts=4 sw=4 et
diff --git a/src/animate.h b/src/animate.h
new file mode 100644
index 0000000..3f8d4a6
--- /dev/null
+++ b/src/animate.h
@@ -0,0 +1,21 @@
+#ifndef COMET_ANIMATE_H
+#define COMET_ANIMATE_H
+
+typedef struct {
+    enum {
+        ANIM_SHINE,
+    } type;
+	GSourceFunc handler;
+} Animation;
+
+double quadratic_bezier(double x, double a, double b, double c);
+
+double cubic_bezier(double x, double a, double b, double c, double d);
+
+Animation *animation_create();
+
+void animation_destroy(Animation *anim);
+
+#endif
+
+// vim: ts=4 sw=4 et
diff --git a/src/button.c b/src/button.c
index 7bee576..01d4e36 100644
--- a/src/button.c
+++ b/src/button.c
@@ -1,6 +1,7 @@
 #include <glib.h>
 
 #include "button.h"
+#include "log.h"
 
 Button *button_simple_create(PangoAlignment align, Color color, Color line_color)
 {
@@ -63,8 +64,41 @@ void button_set_padding(Button *btn, int padding)
 	btn->padding = padding;
 }
 
+bool button_set_animation(Button *btn, Animation *anim)
+{
+	if (btn->anim) return false;
+	btn->anim = anim;
+	return true;
+}
+
+// Wrapper for animation sources
+static gboolean anim_handler(gpointer data)
+{
+	Button *btn = data;
+	if (btn->anim->handler(btn->anim))
+		return G_SOURCE_CONTINUE;
+
+	g_free(btn->anim);
+	btn->anim = NULL;
+	return G_SOURCE_REMOVE;
+}
+
+void button_start_animation(Button *btn)
+{
+	// Maybe error out
+	if (btn->anim == NULL) {
+		log_warning("Button animation was not set");
+		return;
+	}
+
+	const int fps = 60;
+	if (btn->anim->handler(btn->anim))
+		g_timeout_add(1000 / 60, anim_handler, btn);
+}
+
 void button_destroy(Button *btn)
 {
 	if (btn->simple) g_free(CAST(btn, ButtonSimple)->text);
+	animation_destroy(btn->anim);
 	g_free(btn);
 }
diff --git a/src/button.h b/src/button.h
index 0fb821c..923321e 100644
--- a/src/button.h
+++ b/src/button.h
@@ -5,6 +5,8 @@
 #include <glib.h>
 #include <pango/pangocairo.h>
 
+#include "animate.h"
+
 // For pointers only
 #define CAST(ptr, type)   ((type *)ptr)
 
@@ -22,6 +24,7 @@ struct Button {
     PangoAlignment align;
     Color color;
     Color line_color;
+    Animation *anim;
 };
 
 typedef struct {
@@ -57,6 +60,8 @@ void button_group_append(Button *btn, Button *child);
 
 void button_set_padding(Button *btn, int padding);
 
+bool button_set_animation(Button *btn, Animation *anim);
+
 void button_destroy(Button *btn);
 
 #endif