Friday, 4 August 2017

How to map a virtual world to a real space

In February 2017, together with World Wildlife Fund, ArtScience Museum and Google Zoo, MediaMonks launched a large-scale mixed reality experience "Into The Wild" to help people in Singapore experience the devastating effects of deforestation and learn more about some of the world’s most endangered species and their habitats. It was the world’s first Tango-enabled smartphone Lenovo Phab 2 Pro, and guided visitors through personalised digital adventures, which started with AR on the ground floor of the exhibition space, before transitioning to full VR.The end of the experience shifts back to AR, where users go up to the fourth floor for an experience that includes planting a virtual tree.Transforming over 1,000 square meters of the Singapore ArtScience Museum into a virtual, interactive rainforest, making it the largest AR experience in the world, and second ever AR museum experience developed using Google Tango.
And it wasn’t easy. From a technical perspective, we faced the massive challenge of how to accurately and smoothly map a virtual rainforest onto a physical and dynamic museum space, making sure the walls aligned with trees, corridors with the forest’s paths, and that we worked our way around the museum’s existing exhibitions and staging. 

So how did we do it?
To start with, if you’re augmenting the real world with virtual objects, it’s important that the device rendering your view (such as a smartphone, monitor, CAVE or head mounted device) is exactly aware of where it is in the real world.

For this, a device needs to know its position and orientation in a three-dimensional space.

In the case of Tango, where the augmentation happens on a camera feed, the position and orientation of the rendering device needs to be in real world coordinates. Only if the position and orientation of a Tango device is reported accurately, and fast enough, proper augmented reality is possible.The fact that Google Tango does this for you is very cool because it allows developers to augment real world locations within their own virtual world which is different from Snapchat-like AR which, for example, augments bunny ears to your head.

With real world bound augmentations, you can potentially create shared AR experiences that revolve around and involve landmarks.In this case, it allowed us to transform the ArtScience Museum into a lush virtual rainforest and from the user’s perspective, exploring the rainforest becomes as natural as exploring the museum itself because every corridor or obstacle in the virtual world matches a corridor or obstacle in the real one.

Wednesday, 2 August 2017

Black holes lurking at the centre of galaxies could kill stars

The Universe looks very different today compared to how it looked 12 billion years ago. Galaxies once ‘hotspots’ where billions of stars were created are now cosmic graveyards, and exactly what killed these stars has been a mystery until now. Research published today says these galaxies stopped making stars because of black holes lurking at their centres.Astronomers at the University of Iowa studied a few of these galaxies that are still star-making factories, known as dusty starburst galaxies, and found quasars at the centre of four of them.Quasars are extremely bright sources of radio waves, which are powered by disks of matter rotating around supermassive black holes.Stars survive by burning hydrogen gas as fuel, and when this runs out they start to die. The team’s paper argues these quasars are the reason these dusty starburst galaxies became extinct, by ejecting gas far away from the galaxies and starving the stars of their fuel. “The surprising part of the finding is that, although the new ALMA observations located these quasars right at the centres of dusty starburst galaxies, these quasars look the same as other quasars living in normal galaxies,” Hai Fu, assistant professor at the University of Iowa and the paper's first author, told WIRED.

Quasars should not be detectable in dusty starburst galaxies because the light would be absorbed, or blocked, by the dust and gas churned up by the process of star formation.
Fu added: “The starburst galaxies hosting these quasars look the same as other starbursts that don't appear to host quasars.” This means, Fu says, there may be a quasar at the centre of every dusty starburst galaxy, it just cannot be seen. In these particular galaxies where they have been spotted, the researchers think the quasars are peeking out from deep holes, a vacuum free of debris that allows light to escape its cloudy surroundings.

"It's a rare case of geometry lining up," says Jacob Isbell, the paper's second author. "And that hole happens to be aligned with our line of sight."