add 'change-on-release' trackbar property & fix mouseRelease event timing

src/graphics/ui/elements/TrackBar.cpp

@@ -60,11 +60,16 @@ void TrackBar::mouseMove(GUI*, int x, int) {
     value = (value < min) ? min : value;
     value = (int64_t)round(value / step) * step;
 
-    if (consumer) {
+    if (consumer && !changeOnRelease) {
         consumer(value);
     }
 }
 
+void TrackBar::mouseRelease(GUI*, int, int) {
+    if (consumer && changeOnRelease) {
+        consumer(value);
+    }
+}
 
 double TrackBar::getValue() const {
     return value;
@@ -90,6 +95,10 @@ glm::vec4 TrackBar::getTrackColor() const {
     return trackColor;
 }
 
+bool TrackBar::isChangeOnRelease() const {
+    return changeOnRelease;
+}
+
 void TrackBar::setValue(double x) {
     value = x;
 }
@@ -113,3 +122,7 @@ void TrackBar::setTrackWidth(int width) {
 void TrackBar::setTrackColor(glm::vec4 color) {
     trackColor = color;
 }
+
+void TrackBar::setChangeOnRelease(bool flag) {
+    changeOnRelease = flag;
+}

src/graphics/ui/elements/TrackBar.hpp

@@ -14,6 +14,7 @@ namespace gui {
         double value;
         double step;
         int trackWidth;
+        bool changeOnRelease = false;
     public:
         TrackBar(double min, 
                  double max, 
@@ -26,6 +27,7 @@ namespace gui {
         virtual void setConsumer(doubleconsumer consumer);
 
         virtual void mouseMove(GUI*, int x, int y) override;
+        virtual void mouseRelease(GUI*, int x, int y) override;
 
         virtual double getValue() const;
         virtual double getMin() const;
@@ -33,6 +35,7 @@ namespace gui {
         virtual double getStep() const;
         virtual int getTrackWidth() const;
         virtual glm::vec4 getTrackColor() const;
+        virtual bool isChangeOnRelease() const;
 
         virtual void setValue(double);
         virtual void setMin(double);
@@ -40,6 +43,7 @@ namespace gui {
         virtual void setStep(double);
         virtual void setTrackWidth(int);
         virtual void setTrackColor(glm::vec4);
+        virtual void setChangeOnRelease(bool);
     };
 }