Yes, I got your initial idea how you would like to have it working, Big Al. :o) But I don’t know an option to do so.
The IRR was designed, AFAIK, that it stays open and update automatically. So it is a constant information/feedback source. To stop it and start it, as well as change the frame, sounds more like a duty of the Render Region. But feel free to suggest this to MAXON directly http://www.maxon.net/support/suggestions.html
Perhaps you “Right-Mouse-Click” on the triangle of the IRR and open the interface of it (see screen-shot) and integrate this window permanently into your GUI. Save the layout, etc, as mentioned above. But yes, no change of size, even then. I get your idea, but in the moment you would click OK, 20-30 would be needed anyway—following your text above.
The duration of the “refresh-work” needs to be explored. To say anything just in general would not help you here, as each scene is different. Do the following to gain more data: Render the scene the “Picture Viewer” and check the information line on the bottom. How much time is used for the “Preparing ...” is the key here, as this time is needed independently from any pixel rendering. IF this time is long compared to the rendering itself, then the IRR can’t be improved, something else needs to change to get a faster redraw of the IRR. Needless to say that a faster computer would be the key here ;o) but read my 2c about. Having that idea out of the way, you need to think about the bottle neck of your scene.
What is really slowing it down. Is everything needed in the scene all the time, while working. If not, Layer Browser can sort things out. If there is anything that can be cached, do it. If there are tons of generated segments, use the Editor Window>Options>Level of detail. (Perhaps as well the Options in the Render-Settings or as Tag to a specific Object: Level of Detail.
Besides that, is reflections (especially blurry) needed at that stage, or are textures needed. I see often scenes in progress with parts in it that should be worked on later, but which give the illusion of progress—only to slow down the work itself.
My personal two cents:
I work in with computer since the early ‘80s, and with 3D itself since the early ‘90s. My style of work certainly reflects even today a very economical thinking of recourses. Even on an eight core machine, I work with proxies, as model, textures or background video clips. There is always a way to cut things down during the work. Star-Wars movies from the ‘90s were done on 80Mhz CPUs and 256MB Ram with small hard-drives. Today we have at least 100 or 1,000 times the render-power, and it is even then not enough for some projects? I certainly encourage everyone to analysis the work-habbits, as the next larger project might not work without economical use of the recourses. Yes I know there are always reasons, but the one who works fast and economically wins—from my point of view. /
All the best
Sassi
