fix: trackpad scrolling

src/gui/ui/keys.cpp

@@ -40,7 +40,7 @@ bool keys::process_event(const os::Event& event) {
 
 		case os::Event::MouseWheel: {
 			if (event.preciseWheel()) // trackpad
-				scroll_delta = event.wheelDelta().y;
+				scroll_delta_precise = event.wheelDelta().y;
 			else // mouse
 				scroll_delta = event.wheelDelta().y * 2000.f;
 

src/gui/ui/keys.h

@@ -14,6 +14,7 @@ namespace keys {
 	inline std::vector<KeyPress> pressed_keys;
 
 	inline float scroll_delta = 0.f;
+	inline float scroll_delta_precise = 0.f;
 
 	bool process_event(const os::Event& event);
 	void on_input_end();

src/gui/ui/ui.cpp

@@ -260,14 +260,23 @@ bool ui::update_container_input(Container& container) {
 			updated |= (*element.element->update_fn)(container, element);
 	}
 
-	if (keys::scroll_delta != 0.f) {
+	if (keys::scroll_delta != 0.f || keys::scroll_delta_precise != 0.f) {
 		if (container.rect.contains(keys::mouse_pos)) {
 			if (can_scroll(container)) {
 				float last_scroll_speed_y = container.scroll_speed_y;
 
 				container.scroll_speed_y += keys::scroll_delta;
 				keys::scroll_delta = 0.f;
 
+				if (keys::scroll_delta_precise != 0.f) {
+					container.scroll_y += keys::scroll_delta_precise;
+					keys::scroll_delta_precise = 0.f;
+
+					// immediately clamp to edges todo: overscroll with trackpad?
+					int max_scroll = get_max_scroll(container);
+					container.scroll_y = std::clamp(container.scroll_y, 0.f, (float)max_scroll);
+				}
+
 				updated = container.scroll_speed_y != last_scroll_speed_y;
 			}
 		}
@@ -278,6 +287,7 @@ bool ui::update_container_input(Container& container) {
 
 void ui::on_update_end() {
 	keys::scroll_delta = 0.f;
+	keys::scroll_delta_precise = 0.f;
 }
 
 bool ui::update_container_frame(Container& container, float delta_time) {