Remember that 2015 scene in Back To The Future II in which a holographic shark emerges from out of nowhere, and takes a bite out of Marty McFly?
Marty lets out a terrible scream before he realises the shark is not real. But then he comments: "Shark still looks fake."
Well, I did not scream, although I did retreat several steps in disbelief when the HTC Vive virtual reality (VR) headwear I had on plunged me into the most amazing virtual world I had ever experienced up till now.
I cannot wait for the Vive to go on sale.
It is the latest in a not-so-long line of VR hardware being offered to consumers. Announced at last week's Mobile World Congress show in Barcelona, it should be the first video-game-centric system to go on sale by the end of the year.
The much-lauded Oculus Rift has been talked about for a few years, but no launch date has been announced yet. Sony's Project Morpheus is expected only in the first half of next year.
So what makes the Vive work for me?
The basic system has two displays - one for each eye - and fits over your head, creating a 3-D video feed that mimics real life. You could be riding a roller coaster or watching a stage performance, as if you were right there.
Turn your head and the Vive reveals a 360-degree view of the virtual world. A wider peripheral vision adds to the illusion of reality. On that roller coaster, you "see" objects zipping by at high speed, as if you are really in the front seat.
But in any of these worlds, the virtual feed is static. You cannot interact with the environment. It is akin to watching TV when you know the world inside the TV is not a place you can enter.
What sets the Vive apart is that you can actually move around in this virtual world, to examine objects up close.
The headset looks like night-vision goggles, with a curved black module positioned over your eyes. This is where the 1,200 x 1,080 pixel displays (with 90hz refresh rates) are located. During my hands-on session, the headset was connected to the computer and also to two wired controllers.
In the test room were two wired laser positioning sensors, placed at 90 deg to each other on adjoining walls, to track the position of the headset. The final product, sans the headset, will be wireless, HTC said.
Each controller has a trigger button and a circular touchpad.
A whole new world
The first time I switched on the Vive, I really had a sinking feeling. That was because I was "on" the deck of a sunken ship, surrounded by fishes and sea creatures.
I reached out with my controller, pulled the trigger, flicked off some of the fishes - and watched them swim away. I took a few steps forward towards the ship's railings and saw a downed aeroplane in Davy Jones' Locker, alongside a deep dark abyss. Instinctively, I stepped back.
The next thing I knew, a shadow fell over me. As I whirled around, a whale approached me and I froze. This was not for real, I said to myself, but my head disagreed. As the whale swam nearer, I had to convince myself anew that it could not be real because I did not feel the whale's movement.
But the fact that I had to convince myself with a logical reason meant that I had indeed been fooled.
As you walked, the VR world would display a floor-to-ceiling grid which became imaginary walls you could not penetrate. In the test room, the wall sensors created these grids to keep you from inadvertently walking into a real wall.
Next, I found myself in a kitchen that was more Cooking Mama than MasterChef. I used the controller to pick up a tomato, a knife, a piece of steak and operated a microwave oven.
When the food was cooked, I could ring a virtual bell and watch as the plate of food flew away (probably to be delivered to a customer).
The third demo had me standing in the middle of a battlefield, during an ongoing siege of a castle. It was like in those tower defence games.
My head was just above the tabletop battle, which meant that the table was "cutting" my body at the waist. I could move around the field to watch the animated soldiers, and crouch down to examine each of them more closely.
In the fourth clip, my left controller was an artist's colour palette and my right controller was a drawing tool. I could switch colours and tools, and paint on the space in front of me.
What made this amazing was that I could move around the stationary 3D brush stroke or pencil mark I made, and approach my artwork from another angle, as well as add to it. An HTC representative said that the final software would save my virtual artroom, and allow me to share it with friends who could also add to the art piece.
Finally, I found myself in the Aperture Science facility, from the world of Valve's Portal game. It was my job to fix an Atlas android before the time ran out. After pulling out drawers and disassembling the robot, I realised that this was a no-win scenario but, as the walls and floor of the testing room fell apart around me, I could not help but wonder what I could have done to save myself.
The use of the Portal environment is not surprising, as HTC is partnering with Valve, the folks behind the Steam game distribution service. If anything, HTC's job is to make the best hardware in the Vive, and let Valve worry about establishing a credible library of software on the Steam VR game platform.
Pricing details have not been announced, but HTC said that the unit will go on sale in the United States by the end of the year.
The 15 minutes I had with the HTC Vive turned me from a VR sceptic, to a believer in an unreal world, even if it does look fake.
This article was first published on Mar 11, 2015.
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