use floating point for mouse coordinates

modules/v4d/include/opencv2/v4d/v4d.hpp

@@ -126,7 +126,7 @@ class CV_EXPORTS V4D {
     std::future<void> futureWriter_;
     std::function<bool(int key, int scancode, int action, int modifiers)> keyEventCb_;
     std::function<void(int button, int action, int modifiers)> mouseEventCb_;
-    cv::Point mousePos_;
+    cv::Point2f mousePos_;
     uint64_t frameCnt_ = 0;
     bool showFPS_ = true;
     bool printFPS_ = true;
@@ -386,8 +386,8 @@ private:
     void mouse_button_event(int button, int action, int modifiers);
     bool keyboard_event(int key, int scancode, int action, int modifiers);
 
-    cv::Point getMousePosition();
-    void setMousePosition(const cv::Point& pt);
+    cv::Point2f getMousePosition();
+    void setMousePosition(const cv::Point2f& pt);
 
     FrameBufferContext& fbCtx();
     CLVAContext& clvaCtx();

modules/v4d/src/detail/framebuffercontext.cpp

@@ -309,7 +309,7 @@ void FrameBufferContext::init() {
             v4d->nguiCtx().screen().cursor_pos_callback_event(x, y);
         }
 
-        v4d->setMousePosition(cv::Point{x, y});
+        v4d->setMousePosition(cv::Point2f(float(x), float(y)));
     }
     );
     glfwSetMouseButtonCallback(getGLFWWindow(),

modules/v4d/src/v4d.cpp

@@ -81,11 +81,11 @@ bool V4D::keyboard_event(int key, int scancode, int action, int modifiers) {
     return nguiCtx().screen().keyboard_event(key, scancode, action, modifiers);
 }
 
-cv::Point V4D::getMousePosition() {
+cv::Point2f V4D::getMousePosition() {
     return mousePos_;
 }
 
-void V4D::setMousePosition(const cv::Point& pt) {
+void V4D::setMousePosition(const cv::Point2f& pt) {
     mousePos_ = pt;
 }
 
@@ -118,7 +118,6 @@ GLContext& V4D::glCtx(uint32_t idx) {
         glContexts_.insert({idx, ctx});
         return *ctx;
     }
-
 }
 
 bool V4D::hasFbCtx() {
@@ -494,7 +493,7 @@ bool V4D::display() {
 //        swapContextBuffers();
 
 #ifdef __EMSCRIPTEN__
-        nguiCtx().render(printFPS_, showFPS_);
+        nguiCtx().render(printFPS_, showFPS_, showTracking_);
 #endif
         run_sync_on_main<6>([&, this](){
             {