Pre-calculated irradiance map queries

[sambraham]

I was wondering if anyone can help with some irradiance map information.

I am rendering a flyby of a building, only the camera is moving and have precalculated LC & Irr maps. It is quite a big scene and the irr is taking a number of hours to render. I am currently halfway through and have noticed an error I hadn't previously noticed with a part of the pavement surface showing black. It only appears in a couple of sections so I'm thinking funny geometry or overlapping ground plane or something. anyway - can I re-render the irr map after changing this on incremental add to and will it overwrite just that bit if everything else is the same, or, should I stop the calculation now lose the time and start again after making the changes, OR, will it not matter if I change it and just render anyway using this Irr map as it is only the calc pass??!

 

any help or relevant information would be much appreciated as I'm still pretty new to doing animations and haven't quite worked out a decent workflow yet.

 

also just to tag on the end - if anyone can point me to any info regarding best settings for saving out 3d animations, avi mpeg etc that would be great. at the moment I save out to .png and put them together in PS CS3 extended but as I said I'm a bit of a noob to animation and am just finding my animated feet.

 

thanks for looking..hope you can help.

[notamondayfan]

If I were you I would let the whole animation do all the prepasses, and render the animation with the errors. You can then clearly see where the problems are (and probably some other problems too, speaking from bad experiences here!).

 

The you can then re-render only the parts you need to. I would re-calc (save different prepass maps) for the bad areas, and re-render, then paste over the top of the origional animation.

 

As for saving your animation, EXR format works well for me, and give you 32bit floating point to work with too.

 

Dean

[ScottDeW]

Sam,

 

I would continue to render the IR maps as you are doing. Once the IR map is done, just fix the areas in question. Unless you do any drastic moving of objects, you really do not need to re-render the IR map. The detail you'd get back from doing so, you'd probably would not notice. The same thing happens to me every now and then, and I never notice a big difference. Now if you are changing the color drastically (from grey to a bright red), you will want to re-render. But if it's just overlapping faces, I wouldn't worry about it.

 

As for how to render out animations... I highly recommened either rendering out from max in either .tga or .png. The reason being, if the render crashes, you can pick up from the frame it failed at. If you were to render a .mpeg out of max and it crashed, you would have to start from the beginning again. I normally compile my images in Adobe After Effects, but if Photoshop is working for you, then keep going for that. I'm sure there might be some cheap, or even free, video editing software out there that will take in image sequences.

[Tommy L]

Render out 16 bit tiffs. What you compile the movie in depends what software you own. I use Aftereffects.

I think 32 bit is overkill. The movie takes an age to render out of AE and the extra file size is heavy (in your frame storage). I like to keep frames after I finish the project just in case. 32bit frames takes alot of disk space, esp @ 1080p.

So far asa your question about the IR pass, depends on timeframe and what hardware you have. I find taking shortcuts bites me in the ass later on. If you have time to re-render the IR pass then do it.

[notamondayfan]

Render out 16 bit tiffs. What you compile the movie in depends what software you own. I use Aftereffects.

I think 32 bit is overkill. The movie takes an age to render out of AE and the extra file size is heavy (in your frame storage). I like to keep frames after I finish the project just in case. 32bit frames takes alot of disk space, esp @ 1080p.

So far asa your question about the IR pass, depends on timeframe and what hardware you have. I find taking shortcuts bites me in the ass later on. If you have time to re-render the IR pass then do it.

 

Using 32bit generally doesnt slow down exporting or workin in AE, all you need to do is switch to working in 16 or 8 bit work space. I tend to comp everything in 32 bit, then switch to 16 or 8 for export, and sometimes switch if 32 bit is taking too long to edit.

[sambraham]

Thanks for all the advice guys, especially on my first post. It's good to know there's support out there.

 

Once I am compiling the .pngs (in this specific case), what do people recommend for settings for the actual movie? avi's or mpeg's? And what quality settings? The last animation I tried to save I found the balance of file size to quality really hard to figure out. Other animations I'd seen had far higher quality with far lower file sizes for similar subject matters and length. This movie is 30 seconds, 720 frames @ 24fps and I'm rendering 900 x 500 so what kind of file size should I be hoping to achieve? Is that even an answerable question?

[Tommy L]

You should invest in Quicktime Pro. I think its only like $20. Output an uncompressed .avi from Aftereffects. This will give you a humongous file. Its a sum total of every pixel you rendered, so it will be the same size as your frame folder (roughly). Use QT pro to compress this to QT format with default settings. You'll end up with pretty good quality to filesize ratio. Its also a fairly universal format, most people can play it.

I always consider the .avi a 'master'. Its never used for playback, but if the client wants to change the filetype, you dont have to rerender everything out of AE, you have a file that can be chopped/edited and recompressed.