adjusted structure to produce better behavior when vSync is disabled.

src/BaseEngine.cpp

@@ -23,20 +23,21 @@ void BaseEngine::onKeyPressed(ofKeyEventArgs& event)
 
 void BaseEngine::onMouseDragged(ofMouseEventArgs& event)
 {
-    mouseDragged = true;
+    mouseReleased = false;
 }
 
 void BaseEngine::onMousePressed(ofMouseEventArgs& event)
 {
     if(event.button >= 0 && event.button < 5)
     {
         mousePressed[event.button] = true;
+        mouseReleased = false;
     }
 }
 
 void BaseEngine::onMouseReleased(ofMouseEventArgs& event)
 {
-    mouseDragged = false;
+    mouseReleased = true;
 }
 
 void BaseEngine::onMouseScrolled(ofMouseEventArgs& event)

src/BaseEngine.h

@@ -46,7 +46,7 @@ class BaseEngine
     static unsigned int g_ElementsHandle;
 
     bool mousePressed[5] = {false};
-    bool mouseDragged = false;
+    bool mouseReleased = true;
 protected:
     bool isSetup;
 };

src/EngineGLFW.cpp

@@ -108,6 +108,7 @@ void EngineGLFW::onMousePressed(ofMouseEventArgs& event)
     {
         remapToGLFWConvention(button);
         mousePressed[button] = true;
+        mouseReleased = false;
     }
 }
 

src/ofxImGui.cpp

@@ -125,7 +125,9 @@ void ofxImGui::begin()
     io.MousePos = ImVec2((float)ofGetMouseX(), (float)ofGetMouseY());
     for(int i = 0; i < 5; i++){
         io.MouseDown[i] = engine->mousePressed[i];
-        engine->mousePressed[i] = engine->mouseDragged || false;    // Don't set to false if the mouse is being dragged
+
+        // Update for next frame; set to false only if the mouse has been released
+        engine->mousePressed[i] = !engine->mouseReleased;
     }
     ImGui::NewFrame();
 }