Pre-Rendered VS Realtime

Before I got my laptop I showed people youtube clips of the heaven demo, most of peoples computer could barely handle the 720p/1080p youtube clips and then I got my alienware and ran it at 1440*900 in realtime, but people didn't understand the differnce.....

I was first stunned at how they couldn't percive the differnce, and then I was shocked at my inability to explain prerendered movies, everything froming Finding Nemo to Shreq to how thats different then a real time bench mark.

So I guess what I'm asking is how would you explain the differnce between your computer displaying a dvd/blu-ray of Finding Nemo vs running an actuall realtime benchmark like heaven or pcmark

 

Put it in terms non tech-savvy people will understand. It's like watching a re-run vs. a live broadcast. For the re-run, the acting, editing, and processing has already been done, but in the live broadcast it's being shown as it's happening. Obviously, a lot more work must be done for the live broadcast than simply re-showing something which has already been filmed.

 

the best way to explain it is to make it interactive. you could talk about how even though a real time benchmark isn't interactive, that's just because that isn't the point of benchmark. but, it would be really easy for them to set it up so that you could move the camera around freely. interactivity is really the only benefit of running something in real time, so that's the best way to talk about the difference imo.

 

Testing a system's performance (or comparing the performance of multiple systems/configurations with a uniform measurement) is the idea of running a benchmark in real time, not necessarily interactivity.

 

Real-time is the computer doing work to generate a world. Pre-rendered is like a movie; it was recorded, another computer did the work to generate it. Use examples like how it can take hours to generate one frame (mentioning 15-30 frames make up a second) of something really complex like Toy Story 3 on some of the world's fastest computers.

 

Of course. Just trying to figure out a frame of reference to explain it to someone who doesn't immediately understand.

in other words, it might make it easier to explain or to understand if you talk about interactivity, even though that isn't absolutely the only circumstance where real time rendering takes place.

 

youc an move the camera freely in heaven

 

pre-rendered is just like showing frames of pictures, simply bringing the pixels to the screen. For real time, the 3D is generated from 3D models which is just a graph of node locations, texture pixels, and many other calculations such as light etc, then, the calculated scene of what you are supposed to see is rendered to the screen. Pre-rendered videos skips all those steps and simply just renders the pixels to the screen.