add self param to on_press

examples/button.c

@@ -6,9 +6,7 @@
 static const float step = 5.0f;
 static float hue = 360.0f;
 
-static PtkRect *r;
-
-static void on_press(const int button, const int mods) {
+static void on_press(PtkClickable *self, const int button, const int mods) {
     (void)button; (void)mods;
     PTK_DEBUG("pressed!");
 
@@ -17,6 +15,7 @@ static void on_press(const int button, const int mods) {
         hue = 0.0f;
     }
 
+    PtkRect *r = (PtkRect *)self->children.data[0];
     r->color = ptk_hsv_to_rgb((PtkHSV){ .h = hue, .s = 360.0f, .v = 360.0f });
 }
 
@@ -25,13 +24,14 @@ int main(void) {
         return EXIT_FAILURE;
     }
 
-    r = (PtkRect *)ptk_rect(
-        (PtkPos){ .x = 100.0f, .y = 100.0f },
-        (PtkSize){ .w = 100.0f, .h = 50.0f },
-        (PtkRGB){ .r = 1.0f, .g = 0.0f, .b = 0.0f }
-    );
-
     return ptk_run(
-        ptk_clickable((PtkHandle)r, on_press)
+        ptk_clickable(
+            ptk_rect(
+                (PtkPos){ .x = 100.0f, .y = 100.0f },
+                (PtkSize){ .w = 100.0f, .h = 50.0f },
+                (PtkRGB){ .r = 1.0f, .g = 0.0f, .b = 0.0f }
+            ),
+            on_press
+        )
     );
 }

include/ptk.h

@@ -57,7 +57,9 @@ PTK_COMPONENT_DEFINE(PtkEllipse,
     PtkRGB color;
 );
 
-typedef void (*MouseButtonCallback)(const int button, const int mods);
+typedef struct PtkClickable PtkClickable;
+
+typedef void (*MouseButtonCallback)(PtkClickable *self, const int button, const int mods);
 
 PTK_COMPONENT_DEFINE(PtkClickable,
     MouseButtonCallback on_press;

src/ptk_vk/components.c

@@ -183,10 +183,10 @@ void vk_handle_mouse_button_input(const PtkPos cursor_pos, const int button, con
             continue;
         }
 
-        const PtkClickable *c = (PtkClickable *)current;
+        PtkClickable *c = (PtkClickable *)current;
 
         if (intersects((PtkHandle)c, cursor_pos)) {
-            c->on_press(button, mods);
+            c->on_press(c, button, mods);
             vk_update_components();
         }
     }