I’m sure everyone just passed on by on this little download, not knowing what HDR stood for, after all the download is entitled, "Gamefest Unplugged (Europe) 2007: HDR The Bungie Way". Meanwhile it was only posted this March 6th, 2008.
WHAT IS "HDR"?
Well, first a quick explanation: HDR stands for "High Dynamic Range", a lighting style that has become all the craze in the photography and artwork business in the last 3-4 years.
The concept is relatively simple: Maximize the range of bright and dark light on a single photo or painting while still presenting precise & exacting detail and imagery to the viewer. They say a "picture is a thousand words" so here’s a sample of an image using HDR techniques, taken from Wikipedia:
Notice the incredible about of contrast between the lights and darks. Look at how bright the colors are around the illuminated alcoves in the homes and see how dark yet visible the hillsides are leaving up to the castles above. Here’s another:
See how detailed the photo of New York in the darker areas of the photos while the lighted areas in the windows shine bright yet you can still make out the details of the buildings and there’s no "wash out" caused by the contrast. This creates an image that filled with information that is so interesting and beautiful it almost becomes overwhelming in its detail. Entire portrait & painting studios have been created to take advantage of this "newly discovered" technique for photography & painting.
I’m not expert in any of this – I only started getting interested in this stuff because Microsoft has been developing software that allows people to take an overexposed and an underexposed shot and combine the two to create a single HDR image using basic PC technology. Today, HDR photography is an art that is reserved for more expert and experienced photographers.
WHAT DOES BUNGIE HAVE TO DO WITH THIS?
Well, those Bungie guys did a Powerpoint at GameFest, an event that Microsoft holds for game developers, back in 2006 that talked about how to create HDR for video games while taking into consideration the limitations of the hardware, the storage maximums on the DVD media of your game, and the memory available on various gaming systems.
For example, these demonstrate a technique called Bloom Curve that’s not photorealistic however it certainly looks great for gaming. It increases the dynamic range of an image using a ridiculous amount of downsampling and blurring… you have to see the Powerpoint to understand.
Here’s a few highlights:
- Slide 55 talks about the simple technique for combining two prerendered images together to create a single HDR image – similar to what they do in today’s photographic HDR.
- Slides 69 to 83 demonstrate how to add some really cool bloom effects to the visible image to maintain detail in what the player sees while still providing a rich dynamic range of light.
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