Return of the Render Problem

[kennyboy]

When i render a scene, a small section of the floor is missing. It looks like a camera clipping plane problem but if i understand it correctly, clipping plane only affects the viewports not when rendering (I'm i right in saying this?).

A few things to note:

1)The floor is a single plane with one material (the material is multi textured with bumps, spec etc...if it makes a difference?), however small sections of it refuse to render.

2)It's an animation, the first part of the animation renders fine. The later part has a whole sequence of frames (about 50 frames) that has pieces of the floor missing.

3)This suggest that this problem could be related to the position of the camera relative to the floor. I made another camera , smae size, same position, same orientations and camera attributes. This new camera renders the fine! This now suggest theres something wrong with the "animated" camera.

Any ideas????

ps is it better, in terms of rendering speed and maya performance, to use 3 single texture files or one photoshop file with three parts?

Many thanks for reading.

Ken

[kennyboy]

pss is there a quick way of doing camera shake or is it a matter of manually doing it?

[joojaa]

But if i understand it correctly, clipping plane only affects
the viewports not when rendering (I'm i right in saying this?).

Not true, theres even a clippingplane whn you render, its just that whan your camera has autorender clippingplane on it tries to guess the values on its own. This might however fail for many reasons so if its the problem try manualy setting clip planes.

1) if its poly and its for mentalray try triangulating the floor, confuses mr less.

2) well sometimes hierarchy can make it hard for the auto clipplane to react corrctly becvause the matrix gets a bit garbaged. Also it might be dues to mblur or other things. But sometimes its just random things you know.

Ps. depends on circumstances, usualy the 3 smaller maps would nbe better but it realy depends on many things. Also if using bot/map will make a difference here too.

[kennyboy]

Thanks again Joojaa. Once again you have saved my sanity!

After trying out all of ya suggestions and failing, it did end up being the Mblurr problem! Any explaination of this or is it just a maya thing?

I also noticed that sometimes i have problem finishing the render cos of memory exception. I read up about this in the help but not much is said about it except something to do with virtual memory. I found that if i exit maya and then reload the file , i can then render okay. I think this is something to do with flushing the memory (?), if so is there a quicker way of doing this?

I have spent days rendering an animation but i found that large number of frames have randomn casting of shadows on it!!! I know its the camera problem cos if i render it from a different camera (but in the same place) the shadow isnt there! I decided to delete the static channels of the camera and for some reason this, for the time being, have sorted out the shadow problem!!! What the hell is going on??? Maya is doing me 'ead in!

[joojaa]

In reply to:
i can then render okay. I think this is something to do with flushing the memory (?), if so is there a quicker way of doing this?

Not realy, in general ist a good idea to let the rederer start again for every so and so frames. It can be easily don using a for loop form the command line (yes windows knows how to do a loop). Adds a bit of overhead but if you do a fluse asy every 10 or 50 frames it should be okay. Also becaus eit restarts soon after error you dont loose time if you went home after you set teh render going (only on segment will be missing then wich can be coped with using scripts)

[kennyboy]

hmmm that explains a few things then. I found that after coming back from work my so called batch render has done 3 frames out of the 300 and with a message say "done"!!!

Is there a key seach word in help for this "flushing scripting"

Many thanks again

Ken

[joojaa]

its not mel scripting! Batch commands, refeer to your windows help on this one. Its pretty easy to evoke a for loop in commandline to render 3 frames at that time or whatever.

usualy something like this in the commandline

for /L %i in (1,4,300) do for /f "usebackq delims==" %j in (set /a %i+3) do render -s %i -e %j yourfile.ma/mb

will do the trick

Please note this is not realy a cludge solution, even rederers like PRMAN start over every single task PER sub frame component, so that even dmap shadwows would restart renbdering for every time they render. Its the best way to ensure no crash.

Offcourse good dipatching program will keep track of frames thet went awry and so on.

[kennyboy]

I didnt understand all that but thanks for the affect!

I dont like maya render! It's too unstable. This is only the second animation i have done in maya and in both cases i have had major render stability issues. I never have this problem with 3dMAX. I guess i just have to put up with it until i learn how to use maya's rendering software properly!

Thanks again.

[joojaa]

just paste the damn thing into your command prompt on your PC. what is does is it asks maya to render 3 frames then quit and start andother maya render for next 3 franes and so on and so on. VEEERY standard stuff. You dont actualy have to know how the code works just use it.

You just cant asume a renderer does a million frames without any leak, and only way to stop leaks is to restart the renderer every now and then. And yeah maya redeer does try to reuse everything by default wich for complex stuff eats a lot fo memory and once you run out of mem your out of rendering PERIOD (i asume your running on computer with 512 to 1 g of mem right!).

The renderer isnt usntable if you can render 1 frame you can render them all, just your using something there thats leaking a bit, lor uyour running out of memory.

Higher renderer farms have solved this by startting each job separately mayajust glob the thing into one job WICH isnt a good idea at all so what you shouls ALLWAYS do is render in segments. So then you learn to use your computer and ask it to rendr 1 frame at a time.

As for renndering in max, well max is fine as long as it works once it starts working teh things you need to do to circumvent the fact iS WAAAY out there.

you could try not to cache the geo offcourse.