Change visualization demo color function.

src/DemoApp/main.cpp

@@ -181,7 +181,7 @@ const std::string customFragmentColor{
     "vec3(0, 0, 1), diffColor, specColor );\n"
     "vec3 col = normal_world*0.5+0.5;\n"
     "col *= fragCustomAttrib.rgb;\n"
-    "return vec4( (specColor+fragCustomAttrib.rgb)*max(lightDir.z, 0), 1); \n"
+    "return vec4( (specColor+col)*max(lightDir.z, 0), 1); \n"
     "}\n"};
 
 /**
@@ -215,6 +215,7 @@ int main( int argc, char* argv[] ) {
     return app.exec();
 }
 
+
 #if 0
 int main( int argc, char* argv[] ) {