Forums >> Revit Building >> Technical Support >> Maps and Render Times

jsneed665

active

Joined: Wed, May 30, 2007
23 Posts
No Rating

Hello,

I was wondering about maps and rendering.  Maps make the scene look more realistic but  a scene where the entire floor is mapped took over 24 hours to render.  Is this because of the map or another reason?  I have SEVERAL lights. Does this slow the render down as well?  Im trying to figure out if I am doing something wrong that makes the scnenes take so long to render.  thank you

This user is offline

tanielakoroivueta

active

Joined: Mon, Jul 16, 2007
3 Posts
No Rating

1 All rendering software will do this as we become more ambitious to acheive more realistic qualities in our renders. You can't avoid this, and yes super high quality images can take long but this debends on your hardware, your eye for quality and your understanding of how to strategise your scene to acheive that quality.

 Yes, the lighting is definetely the biggest determinant of your rendering time. And also the way your raytracing and radiosity is setup. The greater the reflections the more rendering time. (4 - 6) is good depending on how reflective the materials are. Check out your materials and restrategise your scenes. Some things dont need to reflect that much, i.e. like mirrors or glass in the distance, walls ....etc Strategising your scene is like painting, choose whats most important in the scene and whats not important then create the material settings around that...

I.e. Textures,  etc.. Its the colour in the textures and the resolution of the images that make it more calculation hungry. Good to photoshop your textures down to a pixel size that is respectable to the resolution of your render and the size and position of your object in your scene...

be advised when you bring in an object like a light fitting or a piece of furniture they have their own reflective finishes that can be adjusted to reduce the overcalculations of raytracing or tracing every single litle angle of reflection...

and for lighting Radiosity is the method by which Revit calculates general illuminance levels...i.e. sort of the glow you have in a room. You can run this at a high detail with all the lights in the scene, and then turn some lights off that you know wont be critical shadow and reflection definers in your raytrace...

If you are still hungry for something better, then youll have to try something like Viz or Max.. The same principles apply but they have a better calculation treatment of light...

I know its alot of planning but its either that or get a better machine... hope thats cool.

This user is offline

Timalez

active

Joined: Wed, Jul 29, 2009
24 Posts
No Rating

tanielakoroivueta,

is there another place to control the raytrace settings of the materials?  i have a wood ceiling that I set up as its own material.  I started with a generic material so i would have all the various controls.  the problem is, even when setting all the parameters to not have a gloss finish including setting a "0" for reflectivity, I still get a high gloss finish???

This user is offline

hisdirt

active

Joined: Sun, Nov 6, 2005
123 Posts

Hi there Jsneed665,

The generic material isnt really the most flexible of the materials, it misses out on some great options others have. For example, 'wood'materials have a setting 'bump map based on wood grain' which makes for an easy, effective texture - and ceramic materials have a 'finish bumps' option with a wavy setting that also looks great.

I would suggest basing your wood material of one of the pre-defined woods, rather than using the generic material.

Hope this helps! 

This user is offline

View Website

tanielakoroivueta

active

Joined: Mon, Jul 16, 2007
3 Posts
No Rating

Hello Timalez,

 I agree with Hisdirt regarding the wood texture as an easy option. As for generic material since it's 2010 I am now using... might want to check the glossiness setting in the first row of the material renders dialogue box.

(The second row is the reflectivity settings whether its viewed obliquely or directly)

If you want the material glossiness gone its usually here that you put it to 0. Make sure there is no image file loaded here as well.

FYI:  I don't know what your scene is like, I.E if you have a lot of indirect illuminations. But in the render quality level if you look at the custom settings in the (first row of the render dialogue box) instead of best and better choose custom. There you can globally manage the level of reflections and general ambiance of the mental ray calculations. This is good for managing the quality of the scene, I.e. if you have a lot of glass, or its just flat paint etc. In the previous ray trace version of revit the calculations were highly dependent on the materials editing just as in real life ( but it required lots more power to get it closer to real life). In Mental ray the understanding around lighting is far more superior ( giving the user more efficient ways of improving the lighting to make it more realistic without the need to calculate ...eg. if a reflection is far away it might be blurier so instead of calculating it sharply then blurring it it can just calculate abit then blur smartly around it).

You probably didn't want the FYI but just a thought in terms of the big picture, when you are dealing to materials. Kindly TK.

This user is offline

Timalez

active

Joined: Wed, Jul 29, 2009
24 Posts
No Rating

Thanks for the responses.  I found the problem.  It was a matter of a material that was painted to the face which was taking precedent over the ceiling construction...

 the FYI from tanielakoroivueta was hugely helpful in that these were some of the controls I was looking for... 

Thx!

This user is offline

hisdirt

active

Joined: Sun, Nov 6, 2005
123 Posts

That is also a very good point tanielakoroivueta, about render settings.

The default 'high' and 'best' settings are unnecessarily slow - while the anti-aliasing is required at the higher levels, alot of other settings arent required and add to render time.

Learn what each setting means, and only increase the attributes that are relevant to your render view.

This user is offline

View Website

Problem with Maps

1

Material maps

2

Custom Material

0

Procedural Maps

0

Render times

2