<instructions>Your goal is to analyze the following comment and estimate how highly it will be upvoted by the Hacker News community.</instructions><comment><author>Cushman</author><text>I hope I didn&apos;t seem to be implying there weren&apos;t hard problems in both fields-- but I do think there&apos;s a bigger gap in the current state of the art than you claim.&lt;p&gt;The path to realism in graphics is pretty clear because the real-world behavior of light is well-understood. There may be equations yet to be perfected, and challenges in efficiently simulating that behavior, but the direction is never in question; you can always tell if you&apos;ve made it look more realistic or less.&lt;p&gt;By contrast, AI in games has reached a local maxima; the combination of pathfinding, scripted cues, an elaborate finite state machine, and a few basic heuristics is capable of simulating human behavior well enough, and with few enough glitches, that it presents a realistic universe to the player so long as they don&apos;t exceed the scripted bounds. However, if they do exceed those bounds, the whole thing appears paper-thin. You can extend the bounds with additional effort in scripting, but not infinitely, and with diminishing returns-- and doing so gets you no closer to having real AI which would be able to make those same decisions on its own.&lt;p&gt;Striking out and attempting to make an intelligent NPC-directed world from scratch... I&apos;m not saying it&apos;s impossible, but I haven&apos;t seen anything, from AAA titles to indie games to tech demos, to imply it&apos;s coming soon.&lt;p&gt;But maybe that&apos;s just because I haven&apos;t seen the Minecraft of AI-driven gameplay yet.</text><parent_chain><item><author>gavanwoolery</author><text>As someone who has worked intensively both in the fields of rendering and AI, I can say there are easy and hard problems in both.  There is much in the way of AI that we already know, it&apos;s just that your average developer actually knows very little about AI (not trying to be insulting, it&apos;s just been true in my experience) -- and much more so your average company or publisher does not care to fund AI beyond enemies that can throw themselves into your gun barrel.  Propositional logic, expert systems, backwards chaining, and neural networks are very powerful tools that we know a lot about, but most games rarely implement (perhaps trivially at most).  We still tend to hand-design/script quests, when these fields of AI could provide very powerful emergent gameplay.  What it mostly boils down to (for the sake of interesting gameplay) is proper knowledge-representation (i.e. abstraction) and reasoning (a prolog-like reasoning system would be a good start). And of course, path-finding/locomotion is pretty much a given.  Interestingly, it is less about implementing these and more about designing a game that can use them properly - almost without doubt you need to create a game world that functions on its own, where every NPC has its own set of motivations, which is a very different task from creating a game that is limited to what the player does.&lt;p&gt;Other than that, there are still plenty of hard problems left in rendering, especially with regards to effective procedural generation (which arguably falls more under modeling).  Our ray tracing is still far from &quot;realistic&quot; - take a more complex scene than a table with a wine glass, and we can still usually discern the difference, especially with complex materials and subsurface scattering (human skin STILL does not look quite right).  As it is, we are only able to calculate light travel by &lt;i&gt;points&lt;/i&gt; (we use the term ray tracing, but typically every ray does a number of steps, unless every model is mathematically calculated).  Light travel should be determined by complex &lt;i&gt;volumes&lt;/i&gt; -- which is pretty much impossible to simulate on today&apos;s hardware ( O(n^6) magnitude at least - growing by volume, travel distance, number of objects, volume bounces (dear god), and number of pixels calculated ).</text></item><item><author>Cushman</author><text>Visual quality is an &quot;easy&quot; problem. We know exactly how it ought to work (ray tracing has been photorealistic for some time now), it&apos;s just a matter of tweaking it to run fast enough on the hardware we have. And we&apos;re &lt;i&gt;really close&lt;/i&gt; to pulling it off.&lt;p&gt;AI is, by contrast, a hard problem. We don&apos;t have a very good idea at all of how to exactly simulate a personality, but it&apos;s likely to be orders of magnitude more complex than the most elaborate physical simulation ever designed. The most intelligent NPC ever developed was really, &lt;i&gt;really&lt;/i&gt; stupid. The appearance of realistic characters in games at all is an elaborate stage show. You can spend artist time making the show seem convincing in more circumstances, but evolving it past that &lt;i&gt;at all&lt;/i&gt; is one of the hardest problems in computer science. We&apos;re nowhere near realism.&lt;p&gt;Now, with that said, in the demo they showed off some of their pathfinding and destructible environment improvements. There are plenty of gamers who care just as much (or more) about that stuff.</text></item><item><author>nihilocrat</author><text>Crytek deserves all the praise they get for their hard work in rendering...&lt;p&gt;...but...&lt;p&gt;Why are we conditioned to think that &quot;the future of gaming&quot; is solely a function of a game&apos;s audiovisual quality? I would like to see a &quot;future of gaming&quot; video that shows off  highly-interactive (rather than just very pretty) gameworlds and characters. NPCs that notice you are trying to put a bucket on their heads, for example.</text></item></parent_chain></comment><story><title>CryEngine 3 gives us a glimpse at the future of gaming [video]</title><url>http://www.bgr.com/2012/04/16/cryengine-3-gives-us-a-glimpse-at-the-future-of-gaming-video/</url></story>
<instructions>Your goal is to analyze the following comment and estimate how highly it will be upvoted by the Hacker News community.</instructions><comment><author>sbierwagen</author><text>With AI, there&apos;s also the problem of being more accurate than you want to be. A triple-A title like MW3 or Skyrim is essentially &quot;a movie you walk through&quot;. NPCs have lines, they follow a script.&lt;p&gt;You could easily have NPCs that run a little life simulation, (like in the early versions of Oblivion) but then you have the problem of NPCs going off the script. If you accurately simulate mental states, and some villager rolls a 1 on the d2000 mental state die, then proceeds to kill all the plot-critical NPCs in their village? Now you&apos;ve got a more realistic, yet completely broken, game.</text><parent_chain><item><author>gavanwoolery</author><text>As someone who has worked intensively both in the fields of rendering and AI, I can say there are easy and hard problems in both.  There is much in the way of AI that we already know, it&apos;s just that your average developer actually knows very little about AI (not trying to be insulting, it&apos;s just been true in my experience) -- and much more so your average company or publisher does not care to fund AI beyond enemies that can throw themselves into your gun barrel.  Propositional logic, expert systems, backwards chaining, and neural networks are very powerful tools that we know a lot about, but most games rarely implement (perhaps trivially at most).  We still tend to hand-design/script quests, when these fields of AI could provide very powerful emergent gameplay.  What it mostly boils down to (for the sake of interesting gameplay) is proper knowledge-representation (i.e. abstraction) and reasoning (a prolog-like reasoning system would be a good start). And of course, path-finding/locomotion is pretty much a given.  Interestingly, it is less about implementing these and more about designing a game that can use them properly - almost without doubt you need to create a game world that functions on its own, where every NPC has its own set of motivations, which is a very different task from creating a game that is limited to what the player does.&lt;p&gt;Other than that, there are still plenty of hard problems left in rendering, especially with regards to effective procedural generation (which arguably falls more under modeling).  Our ray tracing is still far from &quot;realistic&quot; - take a more complex scene than a table with a wine glass, and we can still usually discern the difference, especially with complex materials and subsurface scattering (human skin STILL does not look quite right).  As it is, we are only able to calculate light travel by &lt;i&gt;points&lt;/i&gt; (we use the term ray tracing, but typically every ray does a number of steps, unless every model is mathematically calculated).  Light travel should be determined by complex &lt;i&gt;volumes&lt;/i&gt; -- which is pretty much impossible to simulate on today&apos;s hardware ( O(n^6) magnitude at least - growing by volume, travel distance, number of objects, volume bounces (dear god), and number of pixels calculated ).</text></item><item><author>Cushman</author><text>Visual quality is an &quot;easy&quot; problem. We know exactly how it ought to work (ray tracing has been photorealistic for some time now), it&apos;s just a matter of tweaking it to run fast enough on the hardware we have. And we&apos;re &lt;i&gt;really close&lt;/i&gt; to pulling it off.&lt;p&gt;AI is, by contrast, a hard problem. We don&apos;t have a very good idea at all of how to exactly simulate a personality, but it&apos;s likely to be orders of magnitude more complex than the most elaborate physical simulation ever designed. The most intelligent NPC ever developed was really, &lt;i&gt;really&lt;/i&gt; stupid. The appearance of realistic characters in games at all is an elaborate stage show. You can spend artist time making the show seem convincing in more circumstances, but evolving it past that &lt;i&gt;at all&lt;/i&gt; is one of the hardest problems in computer science. We&apos;re nowhere near realism.&lt;p&gt;Now, with that said, in the demo they showed off some of their pathfinding and destructible environment improvements. There are plenty of gamers who care just as much (or more) about that stuff.</text></item><item><author>nihilocrat</author><text>Crytek deserves all the praise they get for their hard work in rendering...&lt;p&gt;...but...&lt;p&gt;Why are we conditioned to think that &quot;the future of gaming&quot; is solely a function of a game&apos;s audiovisual quality? I would like to see a &quot;future of gaming&quot; video that shows off  highly-interactive (rather than just very pretty) gameworlds and characters. NPCs that notice you are trying to put a bucket on their heads, for example.</text></item></parent_chain></comment><story><title>CryEngine 3 gives us a glimpse at the future of gaming [video]</title><url>http://www.bgr.com/2012/04/16/cryengine-3-gives-us-a-glimpse-at-the-future-of-gaming-video/</url></story>