From 3f5735e10f00faf675984a65419b0b9f5725a6c6 Mon Sep 17 00:00:00 2001
From: lisyarus <lisyarus@gmail.com>
Date: Thu, 5 Jan 2023 18:35:39 +0300
Subject: [PATCH] Don't send mouse events to hidden scroller children

---
 libs/ui/include/psemek/ui/element.hpp  |  2 ++
 libs/ui/include/psemek/ui/scroller.hpp |  2 ++
 libs/ui/source/controller.cpp          | 26 +++++++++++++++-----------
 libs/ui/source/element.cpp             |  5 +++++
 libs/ui/source/scroller.cpp            | 13 +++++++++++++
 5 files changed, 37 insertions(+), 11 deletions(-)

diff --git a/libs/ui/include/psemek/ui/element.hpp b/libs/ui/include/psemek/ui/element.hpp
index 5d968ce4..7faafb96 100644
--- a/libs/ui/include/psemek/ui/element.hpp
+++ b/libs/ui/include/psemek/ui/element.hpp
@@ -33,6 +33,8 @@ namespace psemek::ui
 		virtual async::event_loop * loop() const;
 		virtual void set_loop(async::event_loop * loop);
 
+		virtual geom::box<float, 2> events_bbox() const;
+
 		virtual bool on_event(mouse_move  const &) { return false; }
 		virtual bool on_event(mouse_click const &) { return false; }
 		virtual bool on_event(mouse_wheel const &) { return false; }
diff --git a/libs/ui/include/psemek/ui/scroller.hpp b/libs/ui/include/psemek/ui/scroller.hpp
index ea820e31..6e5c5237 100644
--- a/libs/ui/include/psemek/ui/scroller.hpp
+++ b/libs/ui/include/psemek/ui/scroller.hpp
@@ -24,6 +24,8 @@ namespace psemek::ui
 		virtual bool horizontal_scroll() const { return horizontal_; }
 		virtual bool vertical_scroll() const { return vertical_; }
 
+		virtual geom::box<float, 2> events_bbox() const override;
+
 		virtual bool on_event(mouse_move const & e) override;
 		virtual bool on_event(mouse_click const & e) override;
 		virtual bool on_event(mouse_wheel const & e) override;
diff --git a/libs/ui/source/controller.cpp b/libs/ui/source/controller.cpp
index b235c331..a72f2edd 100644
--- a/libs/ui/source/controller.cpp
+++ b/libs/ui/source/controller.cpp
@@ -5,6 +5,7 @@
 #include <psemek/gfx/gl.hpp>
 #include <psemek/util/recursive.hpp>
 #include <psemek/geom/camera.hpp>
+#include <psemek/geom/contains.hpp>
 
 namespace psemek::ui
 {
@@ -73,7 +74,7 @@ namespace psemek::ui
 		impl(async::event_loop * loop);
 
 		template <typename E>
-		element * event(E const & e);
+		element * event(E const & e, bool use_event_bbox = false);
 
 		element * hinted() const;
 
@@ -87,21 +88,24 @@ namespace psemek::ui
 		root->set_loop(loop);
 		root->on_reshape = [this]{
 			if (mouse)
-				event(mouse_move{*mouse});
+				event(mouse_move{*mouse}, true);
 		};
 	}
 
 	template <typename E>
-	element * controller::impl::event(E const & e)
+	element * controller::impl::event(E const & e, bool use_event_bbox)
 	{
 		auto visitor = util::recursive([&](auto && self, element * elem) -> element * {
 			if (elem->hidden()) return nullptr;
 
-			auto cs = elem->children();
-			for (auto it = cs.rbegin(); it != cs.rend(); ++it)
-				if (*it)
-					if (auto p = self(*it))
-						return p;
+			if (!use_event_bbox || geom::contains(elem->events_bbox(), geom::cast<float>(*mouse)))
+			{
+				auto cs = elem->children();
+				for (auto it = cs.rbegin(); it != cs.rend(); ++it)
+					if (*it)
+						if (auto p = self(*it))
+							return p;
+			}
 
 			if (elem->enabled() && elem->on_event(e)) return elem;
 			return nullptr;
@@ -226,7 +230,7 @@ namespace psemek::ui
 	bool controller::event(mouse_move const & e)
 	{
 		impl().mouse = e.position;
-		auto result = impl().event(e);
+		auto result = impl().event(e, true);
 
 		if (impl().hinted_element)
 		{
@@ -265,12 +269,12 @@ namespace psemek::ui
 
 	bool controller::event(mouse_click const & e)
 	{
-		return impl().event(e);
+		return impl().event(e, static_cast<bool>(impl().mouse));
 	}
 
 	bool controller::event(mouse_wheel const & e)
 	{
-		return impl().event(e);
+		return impl().event(e, static_cast<bool>(impl().mouse));
 	}
 
 	bool controller::event(key_press const & e)
diff --git a/libs/ui/source/element.cpp b/libs/ui/source/element.cpp
index f53ef0f8..d6c65b81 100644
--- a/libs/ui/source/element.cpp
+++ b/libs/ui/source/element.cpp
@@ -48,6 +48,11 @@ namespace psemek::ui
 		post_delayed_callbacks();
 	}
 
+	geom::box<float, 2> element::events_bbox() const
+	{
+		return geom::box<float, 2>::full();
+	}
+
 	void element::reshape()
 	{
 		reshape(shape().bbox());
diff --git a/libs/ui/source/scroller.cpp b/libs/ui/source/scroller.cpp
index b94ceb87..7b90a346 100644
--- a/libs/ui/source/scroller.cpp
+++ b/libs/ui/source/scroller.cpp
@@ -22,6 +22,19 @@ namespace psemek::ui
 		return enabled;
 	}
 
+	geom::box<float, 2> scroller::events_bbox() const
+	{
+		auto st = merged_own_style();
+		auto result = shape_.box;
+
+		if (horizontal_scroll())
+			result[1].max -= width() * *st->scale;
+		if (vertical_scroll())
+			result[0].max -= width() * *st->scale;
+
+		return result;
+	}
+
 	bool scroller::on_event(mouse_move const & e)
 	{
 		mouse_ = e.position;