[Grid] Unknown is transparent now

src/perceptions_display.cpp

@@ -237,11 +237,12 @@ void PerceptionsDisplay::processMessage(const multiception::Perceptions::ConstPt
 		for(size_t i=0; i<gridmapmsg->data[0].data.size(); i++)
 		{
 			gridmapmsg->data[0].data[i] = gridmapmsg->data[1].data[i] - gridmapmsg->data[2].data[i];
+			gridmapmsg->data[3].data[i] = (gridmapmsg->data[3].data[i]<0.999) ? gridmapmsg->data[3].data[i] : NAN;
 		}
 
 		gridVisual->setMessage(gridmapmsg);
 		const float gridAlpha = alpha_property_->getFloat() * grid_alpha_property_->getFloat();
-		gridVisual->computeVisualization(gridAlpha, false, false, "o,O", false, false, Ogre::ColourValue(0.8, 0.8, 0.8), false, "", "default", true, false, Ogre::ColourValue(0, 0, 0), Ogre::ColourValue(), false, -1, 1, 0.1, 1);
+		gridVisual->computeVisualization(gridAlpha, false, true, "o,O", false, false, Ogre::ColourValue(0.8, 0.8, 0.8), false, "", "default", true, false, Ogre::ColourValue(0, 0, 0), Ogre::ColourValue(), false, -1, 1, 0.1, 1);
 		grid_visuals_.push_back(gridVisual);
 	}