Reducing Rendering time.

I am not a rendering man, but a certain project involving a large steel structured buildings took many days for the preparation of a walkthrough, couple of years ago. Is there no way of reducing the time?. I understand that this process involves solving of differential equations for reflection of light from various materials in the building etc. Can it not be done through Autolisp instead of going through .NET languages. Common Lisp is also a powerful OOP language. If Alisp cannot do it can Autodesk implement CL and cut short the time?.

There are tons of things that affect rendering times.

The big questions would be:

• How large must the images be
  
• How many frames are you doing
  
• What would you consider to be an acceptable time limit for each frame
  

I just finish a project with 2,550 frames @1,536 x 864 that averaged 2 min 20 sec per frame ( 4.5 days ). For me that is a long time in this day and age because I'm used to 20-30 seconds to render each frame. ( The models had tons of glass panels) I could have cut this time in half if I had used one on newer machines, but didn't want tie it up for a couple of days.

Things that can cause render times to increase:

• Highly reflective materials
  
• Rounded surface or corners
  
• Too many light sources
  
• Refraction and reflections settings that are too high
  
• Background materials that are too detailed
  

And last but not least, throw as much hardware at the process as you can and keep that machine as lean as possible as far as the number of processes that are running in the background.

I use a larger than required frame size so that I can use a resizing filter as I compile the movie. My final frame size is 1,280 x 720 ( 16:9 HD in You Tube ). It takes a bit longer, but the final results are better.

The stepping thru the path shouldn't be the time issue. So whether its is done thru lisp and any other programming language should take about the same time. I would guess it take 1 second or so to transition from 1 frame to the next. It's the rendering engine. ( I take you are using AutoCADs built in render. )

-David

Is this (rendering) something you'll be doing often enough to justify the cost of a dedicated piece of hardware?

Powerhouse rendering systems.

http://www.boxxtech.com/

Hi ReMark,

Thanks for the link.

Aloy

Sure thing. Don't forget to keep in mind what David said in the mean time.

Hi David,

Thanks for the extensive info.

What I am suggesting is a fundamental shift in the way rendering is done. Why Adesk does not try a different approach by changing the technology with respect to the methodology involved in the calculations and using a different language somewhat similar to Alisp or Vlisp which are currently used to run AutoCAD. I do not think .Net languages run AutoCAD.

Regards,

Aloy

Maybe you're using the wrong program.

From what david said and the link you sent, it appears the technology used is the same. We did the designs of this project around mid 2010 and had a presentation. I am no longer in that office. (I am currently writing from a different country). So, I do not have access to the details at this time. My complaint is why is it so time consuming for Rendering in this age when Americans have technology to land a robot safely on Mars, several billions of mile away. We should be doing things faster on terra firma.

Regards,

Aloy

I don't do hardware design but if I change fields I'll put your problem at the top of my list to solve. Best I can do.

I still think you need to look at another program to do your rendering.

BTW...what do you have for a computer setup re: hardware? How much physical RAM? What OS are you running? Is it 64-bit? What co-processor is being used?

I use old software for that very reason. I render using Accurender 2.0 in Release 13 On a 64 bit Windows 7 machine. For a single image, I make 2,000 x 1,600 images in under 1 minute using just about every option that Accurender can offer.

In my experience, then newer is not faster or better. In fact until 2010 or so, I thought AutoCAD's rendering engine wasn't very good. Hell it takes a minute or so just to get 2012 fully loaded. I'm still not impressed with it's rendering interface.

Have you looked at other rendering packages. Some do very nice renderings. I don't know how they stack up on time and performance.

I like older Accurender programs because it has an API for AutoCAD and I can then automate the process via Autolisp.

-David

REMark,

I remember we used Windows XP v3. 2gb Ram and I think the processor was pentium 3 or 4.

Thanks for replying.

Aloy

By today's standards that is a very weak system.

What I am suggesting is a fundamental shift in the way rendering is done. Why Adesk does not try a different approach by changing the technology with respect to the methodology involved in the calculations and using a different language somewhat similar to Alisp or Vlisp which are currently used to run AutoCAD. I do not think .Net languages run AutoCAD.

The software, or programming language, is not the bottleneck. It's the processing power of the computer. Build yourself a render farm and see how much faster you can render on multiple computers as opposed to a single computer. The more processors you have, the faster you can render. Although I'm not sure that you can run Autocad on a render farm. You would have to switch to Studio Max for that.

This would be be an ideal candidate for Autodesk's cloud service. They would be able to dedicate some real horsepower to the task at hand and likely get the job done in a small fraction of the time it would take to do it on your own. I'm not certain if it is configurable to automate walk throughs or animation but I can't imagine it not being a consideration.

AutoCAD cannot adequately avail itself of multiple cores when it comes to rendering as I understand it. 3ds Max would be the better choice.

Cad64,

Thank you for the info,

In this part of the world (South and South East Asia ) we use AutoCAD for drafting and these are used for Rendering, hence my question in AutoCAD forum. All replies above are based on the current technology available for rendering, and that is going through the tedius process involved in complicated calculations. My question is actually for those involved in the development of code. I am sure Adesk also did that, for them to have a section on rendering. Yes, as advised one way is to have a rendering farm, but a dedicated system like that is not viable for most consultants over here.

Regards,

Aloy

You do realize that building a render farm costs relatively nothing, right? All you need are some spare computers, one licensed copy of Studio Max, the Backburner render management software that ships with Studio Max, a switch box and cables to network the computers together and a little bit of your time to set it up. The only real investment is the Studio Max software.

Your initial question was why can't Autodesk use a different programming language for rendering, but the answer is that the programming language really has nothing to do with the issue. The problem lies with the computer processors ability to process all the information. The solution to the problem is to have as many processors as possible, hence the render farm. If you had 100 processors you could render in minutes as opposed to hours.

But, if the consultants over there cannot justify a dedicated system like that, there are online services that will render for you, like the Autodesk cloud service that Patrick suggested.

Open yourself to the possibilities and stop throwing up your own roadblocks. There is a wealth of information right at your fingertips. Seek and ye shall find. Take a look at this.

http://www.tomshardware.com/reviews/render-farm-node,2340.html

Cad64,

Our computers are networked, so no problem about the farm if they need not be powerful ones. Should the computers be of the same power?. I hope Studio Max give those details. My question on the process, that is writing a simplified algorithm for the development of code still stands.

Do they use cloud computing extensively in the US right now?. How reliable is it?.

Regards,

Aloy

I would separate the render farm from the network.