5 ms·

Could it explain why we are seeing more improvements in rendering quality compared to physics and AI? As you said, AI and physics are inherently not really par

Could it explain why we are seeing more improvements in rendering quality compared to physics and AI? As you said, AI and physics are inherently not really parallelizable while rendering is. AI and physics from the Athlon 64/Pentium 4 era (e.g. Half-Life 2, Crysis) are similar to what we get now, while visual quality greatly improved (better textures, more detailed objects, longer visibility range).

rcxdude 6y ago
I think for AI the core reason is more sophisticated AI isn't particularly great from a game design POV. In a game, predictability is key, both because a) it allows the game designers to actually change the AI behaviour to balance it and be able to incorporate it into their game design, and b) if the players can't predict the AI they can't plan around it, and the ability to make a plan around a game's systems and try to execute it is a key part of non-frustrating gameplay in most games. The more state-of-the-art AI systems tend to become less predictable and for the most part that makes the games less fun. In terms of physics usually the issue is if you have a rich physics envrionment it gets more fragile: it's easier for players to break it, intentionally or unintentionally. I've played some games with physics systems far in advance in terms of number of objects than could be achieved previously and they are all pretty much just 'buggy', not necessarily in terms of coding quality, just in terms of how rigid body physics is really prone to creating edge cases which create massive forces, velocities, and/or accelerations from apparently benign arrangements of objects.
- leetcrew 6y ago
  I think you're right; at least it jives with everything I've read about game dev. a common design goal in modern games is to never allow the game to fall into a state where forward progress is impossible due to a player action (excepting stuff like dying, of course). realistic physics simulation adds a lot of weird edge cases that need to be tested or hacked around. unlike cs:go, cs:source had lots of collidable physics props in the maps. they looked benign at first, but malicious players could use them to block important passages, make it impossible to defuse the bomb, or arrange them in ways that other players would get stuck in them. here's a video of hl2 devs reacting to a speedrun of the game using many exploits: https://www.youtube.com/watch?v=sK_PdwL5Y8g https://www.youtube.com/watch?v=sK_PdwL5Y8g kind of a long video, but there's a lot of interesting commentary on how much work it was to make the physics puzzles robust against unexpected player actions.
steerablesafe 6y ago
I have no experience with game development, but I have some experience in HPC physics simulations. Many physics simulations are embarrassingly parallelizable. I suspect that this is mostly a latency/throughput kind of balance for real time simulations. In games the results have to be ready the next frame.

rcxdude 6y ago

I think for AI the core reason is more sophisticated AI isn't particularly great from a game design POV. In a game, predictability is key, both because a) it allows the game designers to actually change the AI behaviour to balance it and be able to incorporate it into their game design, and b) if the players can't predict the AI they can't plan around it, and the ability to make a plan around a game's systems and try to execute it is a key part of non-frustrating gameplay in most games. The more state-of-the-art AI systems tend to become less predictable and for the most part that makes the games less fun. In terms of physics usually the issue is if you have a rich physics envrionment it gets more fragile: it's easier for players to break it, intentionally or unintentionally. I've played some games with physics systems far in advance in terms of number of objects than could be achieved previously and they are all pretty much just 'buggy', not necessarily in terms of coding quality, just in terms of how rigid body physics is really prone to creating edge cases which create massive forces, velocities, and/or accelerations from apparently benign arrangements of objects.

leetcrew 6y ago
I think you're right; at least it jives with everything I've read about game dev. a common design goal in modern games is to never allow the game to fall into a state where forward progress is impossible due to a player action (excepting stuff like dying, of course). realistic physics simulation adds a lot of weird edge cases that need to be tested or hacked around. unlike cs:go, cs:source had lots of collidable physics props in the maps. they looked benign at first, but malicious players could use them to block important passages, make it impossible to defuse the bomb, or arrange them in ways that other players would get stuck in them. here's a video of hl2 devs reacting to a speedrun of the game using many exploits: https://www.youtube.com/watch?v=sK_PdwL5Y8g https://www.youtube.com/watch?v=sK_PdwL5Y8g kind of a long video, but there's a lot of interesting commentary on how much work it was to make the physics puzzles robust against unexpected player actions.

steerablesafe 6y ago

I have no experience with game development, but I have some experience in HPC physics simulations. Many physics simulations are embarrassingly parallelizable. I suspect that this is mostly a latency/throughput kind of balance for real time simulations. In games the results have to be ready the next frame.