Estimating render time

[Cephei]

Yeah I always wondered how renderers estimation times worked...

[neuspadrin]

probably some sort of algorithm that basically just keeps track of how much time it has been rendering to get to that specific point, and how much rendering is left, which is why it can be quite a bit off, and slowly becomes more accurate. Could perhaps use a average of time perpixel, etc etc.  Theres little small ways to guestimate the time it'll take, but its never fully accurate. 

I am curious to see if you can render all the high settings with a small res picture (like 640x480), and then  be able to accurately calculate how long it would at like 1920x1200 or something.

[Oshyan]

Couple things here. First off, some rendering systems are actually a lot more predictable than others, so in those systems sometimes render time remaining indicators are provided. In TG2 virtually everything is computed at render time, so it's very hard to predict.

The other thing is that the larger the difference between your test render size and your target output size, the less accurate the test/prediction would be. So going from 640x480 to 1600x1200 would be harder to predict than going from 320x240 to 640x480, or 640x480 to 800x600 for that matter.

- Oshyan

[Cyber-Angel]

What about tacking a known instance say the time it takes to render a square of a known size say 8 X 8 Pixels and you know that will require Time X to render this then is a known quantity, you have an image you wish to render at say a resolution of say 2040 X 1530 and you know that your 8 X 8 pixel square goes Y number of times into that resolution you can then predict since you have a know quantity how long a render should take.

This is a simplistic model I know but shows a way it might be done.

Regards to you.

Cyber-Angel

[Oshyan]

Like I just said, the larger the difference between your test resolution and your target resolution, the less accurate the prediction. In the case of your suggestion, I'd say it would be pretty inaccurate.

- Oshyan