This is Part 1 of a series examining techniques used in game graphics and how those techniques fail to deliver a visually appealing end result. See Part 0 for a more thorough explanation of the idea behind it.
High dynamic range. First experienced by most consumers in late 2005, with Valve’s Half Life 2: Lost Coast demo. Largely faked at the time due to technical limitations, but it laid the groundwork for something we take for granted in nearly every blockbuster title. The contemporaneous reviews were nothing short of gushing. We’ve been busy making a complete god awful mess of it ever since.
Let’s review, very quickly. In the real world, the total contrast ratio between the brightest highlights and darkest shadows during a sunny day is on the order of 1,000,000:1. We would need 20 bits of just luminance to represent those illumination ranges, before even including color in the mix. A typical DSLR can record 12-14 bits (16,000:1 in ideal conditions). A typical screen can show 8 (curved to 600:1 or so). Your eyes… well, it’s complicated. Wikipedia claims 6.5 (100:1) static. Others disagree.
Graphics programmers came up with HDR and tone mapping to solve the problem. Both film and digital cameras have this same issue, after all. They have to take enormous contrast ratios at the input, and generate sensible images at the output. So we use HDR to store the giant range for lighting computations, and tone maps to collapse the range to screen. The tone map acts as our virtual “film”, and our virtual camera is loaded with virtual film to make our virtual image. Oh, and we also throw in some eye-related effects that make no sense in cameras and don’t appear in film for good measure. Of course we do.
And now, let’s marvel in the ways it goes spectacularly wrong.
In order: Battlefield 1, Uncharted: Lost Legacy, Call of Duty: Infinite Warfare, and Horizon Zero Dawn. HZD is a particular offender in the “terrible tone map” category and it’s one I could point to all day long. And so we run head first into the problem that plagues games today and will drive this series throughout: at first glance, these are all very pretty 2017 games and there is nothing obviously wrong with the screenshots. But all of them feel videogamey and none of them would pass for a film or a photograph. Or even a reasonably good offline render. Or a painting. They are instantly recognizable as video games, because only video games try to pass off these trashy contrast curves as aesthetically pleasing. These images look like a kid was playing around in Photoshop and maxed the Contrast slider. Or maybe that kid was just dragging the Curves control around at random.
The funny thing is, this actually has happened to movies before.
Hahaha. Look at that Smaug. He looks terrible. Not terrifying. This could be an in-game screenshot any day. Is it easy to pick on Peter Jackson’s The Hobbit? Yes, it absolutely is. But I think it serves to highlight that while technical limitations are something we absolutely struggle with in games, there is a fundamental artistic component here that is actually not that easy to get right even for film industry professionals with nearly unlimited budgets.
Allow me an aside here into the world of film production. In 2006, the founder of Oakley sunglasses decided the movie world was disingenuous in their claims of what digital cameras could and could not do, and set out to produce a new class of cinema camera with higher resolution, higher dynamic range, higher everything than the industry had and would exceed the technical capabilities of film in every regard. The RED One 4K was born, largely accomplishing its stated goals and being adopted almost immediately by one Peter Jackson. Meanwhile, a cine supply company founded in 1917 called Arri decided they don’t give a damn about resolution, and shipped the 2K Arri Alexa camera in 2010. How did it go? 2015 Oscars: Four of the five nominees in the cinematography category were photographed using the ARRI Alexa. Happy belated 100th birthday, Arri.
So what gives? Well, in the days of film there was a lot of energy expended on developing the look of a particular film stock. It’s not just chemistry; color science and artistic qualities played heavily into designing film stocks, and good directors/cinematographers would (and still do) choose particular films to get the right feel for their productions. RED focused on exceeding the technical capabilities of film, leaving the actual color rendering largely in the hands of the studio. But Arri? Arri focused on achieving the distinctive feel and visual appeal of high quality films. They better understood that even in the big budget world of motion pictures, color rendering and luminance curves are extraordinarily difficult to nail. They perfected that piece of the puzzle and it paid off for them.
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