Preserve mouse capture per pointer

Engine/system/api/iosapi.mm

@@ -268,6 +268,11 @@ -(id)init {
   return self;
   }
 
+- (void)setView:(UIView*)view {
+  view.multipleTouchEnabled = YES;
+  [super setView:view];
+  }
+
 - (void)viewDidLoad {
   [super viewDidLoad];
   self.extendedLayoutIncludesOpaqueBars = YES;

Engine/system/eventdispatcher.cpp

@@ -27,7 +27,7 @@ void EventDispatcher::dispatchMouseDown(Widget& wnd, MouseEvent &e) {
                  Event::MouseDown );
   e1.ignore();
 
-  auto& btn = mouseUp[e.button];
+  std::weak_ptr<Widget::Ref> btn;
   for(auto i:overlays) {
     if(!i->bind(wnd))
       continue;
@@ -37,6 +37,7 @@ void EventDispatcher::dispatchMouseDown(Widget& wnd, MouseEvent &e) {
     if(e1.type()==MouseEvent::MouseDown) {
       mouseLast    = btn;
       mouseLastBtn = e.button;
+      mouseLastId  = e.mouseID;
       }
     }
 
@@ -52,8 +53,11 @@ void EventDispatcher::dispatchMouseDown(Widget& wnd, MouseEvent &e) {
     mouseLast     = btn;
     mouseLastTime = Application::tickCount();
     mouseLastBtn  = e.button;
+    mouseLastId   = e.mouseID;
     }
 
+  reset(e.mouseID, e.button, btn);
+
   if(auto w = btn.lock()) {
     if(w->widget->focusPolicy() & ClickFocus) {
       w->widget->implSetFocus(true,Event::FocusReason::ClickReason);
@@ -64,9 +68,7 @@ void EventDispatcher::dispatchMouseDown(Widget& wnd, MouseEvent &e) {
 void EventDispatcher::dispatchMouseUp(Widget& /*wnd*/, MouseEvent &e) {
   ++mouseEvCount;
 
-  auto ptr = mouseUp[e.button];
-  mouseUp[e.button].reset();
-
+  std::weak_ptr<Widget::Ref> ptr = reset(e.mouseID, e.button);
   if(auto w = ptr.lock()) {
     auto p = e.pos() - w->widget->mapToRoot(Point());
     MouseEvent e1( p.x,
@@ -81,14 +83,15 @@ void EventDispatcher::dispatchMouseUp(Widget& /*wnd*/, MouseEvent &e) {
   }
 
 void EventDispatcher::dispatchMouseMove(Widget& wnd, MouseEvent &e) {
-  auto btn = Event::ButtonNone;
-  for(uint8_t i=0; i<Event::ButtonLast; ++i)
-    if(!mouseUp[i].expired()) {
-      btn = Event::MouseButton(i);
-      break;
+  auto btn = Event::ButtonLast;
+  for(auto& i:mouseUp)
+    if(i.id==e.mouseID && i.button<btn && !i.ref.expired()) {
+      btn = i.button;
       }
+  if(btn==Event::ButtonLast)
+    btn = Event::ButtonNone;
 
-  if(auto w = lock(mouseUp[btn])) {
+  if(auto w = lock(e.mouseID,btn)) {
     auto p = e.pos() - w->widget->mapToRoot(Point());
     MouseEvent e0( p.x,
                    p.y,
@@ -102,7 +105,7 @@ void EventDispatcher::dispatchMouseMove(Widget& wnd, MouseEvent &e) {
       return;
     }
 
-  if(auto w = lock(mouseUp[btn])) {
+  if(auto w = lock(e.mouseID,btn)) {
     auto p = e.pos() - w->widget->mapToRoot(Point());
     MouseEvent e1( p.x,
                    p.y,
@@ -113,7 +116,7 @@ void EventDispatcher::dispatchMouseMove(Widget& wnd, MouseEvent &e) {
                    Event::MouseMove  );
     w->widget->mouseMoveEvent(e1);
     if(e.isAccepted()) {
-      implSetMouseOver(mouseUp[btn].lock(),e);
+      implSetMouseOver(lock(e.mouseID,btn),e);
       return;
       }
     }
@@ -304,7 +307,7 @@ std::shared_ptr<Widget::Ref> EventDispatcher::implDispatch(Widget& w, MouseEvent
       auto     last     = mouseLast.lock();
       bool     dblClick = false;
       uint64_t time     = Application::tickCount();
-      if(time-mouseLastTime<1000 && mouseLastBtn==event.button && last!=nullptr && last->widget==it.owner) {
+      if(time-mouseLastTime<1000 && mouseLastBtn==event.button && mouseLastId==event.mouseID && last!=nullptr && last->widget==it.owner) {
         dblClick = true;
         }
       event.accept();
@@ -521,6 +524,29 @@ std::shared_ptr<Widget::Ref> EventDispatcher::lock(std::weak_ptr<Widget::Ref>& w
   return nullptr;
   }
 
+std::shared_ptr<Widget::Ref> EventDispatcher::lock(int id, Event::MouseButton button) {
+  for(auto& i:mouseUp)
+    if(i.id==id && i.button==button)
+      return lock(i.ref);
+  return nullptr;
+  }
+
+std::weak_ptr<Widget::Ref> EventDispatcher::reset(int id, Event::MouseButton button, const std::weak_ptr<Widget::Ref>& w) {
+  for(auto i=mouseUp.begin(); i!=mouseUp.end(); ++i)
+    if(i->id==id && i->button==button) {
+      auto ptr = i->ref;
+      if(w.expired()) {
+        mouseUp.erase(i);
+        } else {
+        i->ref = w;
+        }
+      return ptr.lock();
+      }
+  if(!w.expired())
+    mouseUp.push_back({button,id,w});
+  return {};
+  }
+
 Event::Modifier EventDispatcher::mkModifier() const {
   uint8_t ret = 0;
   if(keyMod.ctrlL || keyMod.ctrlR)

Engine/system/eventdispatcher.h

@@ -4,6 +4,7 @@
 #include <Tempest/Event>
 
 #include <unordered_map>
+#include <vector>
 
 namespace Tempest {
 
@@ -33,6 +34,12 @@ class EventDispatcher final {
     void dispatchDestroyWindow(SystemApi::Window* w);
 
   private:
+    struct MouseCapture {
+      Event::MouseButton          button = {};
+      int                         id     = 0;
+      std::weak_ptr<Widget::Ref>  ref    = {};
+      };
+
     std::shared_ptr<Widget::Ref> implDispatch(Tempest::Widget &w, Tempest::MouseEvent& event);
     std::shared_ptr<Widget::Ref> implDispatch(Tempest::Widget &w, Tempest::FocusEvent& event);
     void                         implMouseWheel(Widget &w, MouseEvent &event);
@@ -44,16 +51,19 @@ class EventDispatcher final {
     void                         handleModKey(const KeyEvent& e);
 
     std::shared_ptr<Widget::Ref> lock(std::weak_ptr<Widget::Ref>& w);
+    std::shared_ptr<Widget::Ref> lock(int id, Event::MouseButton button);
+    std::weak_ptr<Widget::Ref>   reset(int id, Event::MouseButton button, const std::weak_ptr<Widget::Ref>& w = {});
 
     Widget*                      customRoot = nullptr;
-    std::weak_ptr<Widget::Ref>   mouseUp[Event::MouseButton::ButtonLast];
+    std::vector<MouseCapture>    mouseUp;
     std::weak_ptr<Widget::Ref>   mouseLast;
     std::weak_ptr<Widget::Ref>   mouseOver;
 
     std::weak_ptr<Widget::Ref>   focusLast;
 
     std::vector<UiOverlay*>      overlays;
     Event::MouseButton           mouseLastBtn  = Event::MouseButton::ButtonNone;
+    int                          mouseLastId   = 0;
     uint64_t                     mouseLastTime = 0;
     uint64_t                     mouseEvCount  = 0;