some imgui side fixes

Author: d3cod3

src/core/imgui_node_canvas.cpp

@@ -756,6 +756,8 @@ ImGuiEx::NodeConnectData ImGuiEx::NodeCanvas::AddNodePin( const int nodeID, cons
             ImGui::InvisibleButton("nodeBtn", ImMax(ImVec2(pinLayout.pinSpace.x,pinLayout.pinSpace.y*.8f), ImVec2(1,1)));
 # endif
 
+            IM_ASSERT( _label != NULL );
+
             std::string _str_label(_label);
             std::string _gui_label(_label);
             _str_label += std::to_string(pinID);

src/core/imgui_plot.cpp

@@ -417,7 +417,7 @@ void PlotBands(ImDrawList* drawList, float width, float height, std::vector<floa
     float bin_w = Canvas.x / data->size();
 
     for(unsigned int i=0;i<data->size();i++){
-        drawList->AddRect(ImVec2( bb.Min.x + (bin_w*i), bb.Min.y+(Canvas.y*(max-data->at(i)) )),ImVec2(bb.Min.x + (bin_w*i) + bin_w, bb.Max.y),color);
+        drawList->AddRect(ImVec2( bb.Min.x + (bin_w*i), bb.Min.y+(Canvas.y*(max-data->at(i)) )),ImVec2(bb.Min.x + (bin_w*i) + bin_w, bb.Max.y),color,0,0,1);
     }
 
 }