draw main brush preview first if the queue is long

src/node_panel_brush.cpp

@@ -443,8 +443,8 @@ kEventResult NodePanelBrushPreset::handle_event(Event* e)
 
 void NodePanelBrushPreset::handle_click(Node* target)
 {
-    if (target == m_current)
-        return;
+    //if (target == m_current)
+    //    return;
     if (m_current)
         m_current->m_selected = false;
     m_current = (NodeBrushPresetItem*)target;

src/node_panel_stroke.cpp

@@ -428,6 +428,8 @@ void NodePanelStroke::init_controls()
 
 
     m_preview = find<NodeStrokePreview>("canvas");
+    m_preview->m_draw_first = true;
+
     m_blend_mode = find<NodeComboBox>("blend-mode");
     m_blend_mode->on_select = [this](Node*, int index) {
         Canvas::I->m_current_brush->m_blend_mode = index;

src/node_stroke_preview.cpp

@@ -509,7 +509,7 @@ void NodeStrokePreview::draw_stroke()
         });
     }
     s_queue.mutex.unlock();
-    s_queue.PostUnique(this);
+    s_queue.PostUnique(this, m_draw_first);
 }
 
 void NodeStrokePreview::draw()

src/node_stroke_preview.h

@@ -32,6 +32,7 @@ public:
     static void terminate_renderer();
     std::shared_ptr<Brush> m_brush;
     std::shared_ptr<Brush> m_dual_brush;
+    bool m_draw_first = false;
     Stroke m_stroke;
     Stroke m_dual_stroke;
     std::vector<glm::vec2> m_bez_points;

src/util.h

@@ -173,7 +173,7 @@ public:
         q.push_back(pkt);
         get_cv.notify_one();
     }
-    void PostUnique(T pkt)
+    void PostUnique(T pkt, bool top)
     {
         std::unique_lock<std::mutex> lock(mutex);
         if (Max > 0)
@@ -182,7 +182,7 @@ public:
             if (q.size() >= Max) return;
         }
         if (std::find(q.begin(), q.end(), pkt) == q.end());
-            q.push_back(pkt);
+            top ? q.push_front(pkt) : q.push_back(pkt);
         get_cv.notify_one();
     }
     T Get()