Final Renderworks Settings ?

[MikeB]

I noticed that final renderworks rendering seems slower under 12, then I noticed that the defaut recursion level for the custom renderworks is 64. Is this also the recursion level for the final mode. If so that explains alot, I thought the limit on recursion level under 11 was 9.

Thanks

[Dave_Donley]

Hello MikeB:

This change will only make a scene render slower if that scene actually has reflective surfaces that would bounce between themselves dozens of times, which does not happen easily. This default was changed so that overlapping image props render correctly up to 32 overlapping props.

Does your file have a lot of reflecting objects that would reflect each other in them?

[MikeB]

It has a few refelctive surfaces, some glass, some chairs with aluminum legs. Its also a bit of a mess as far as files go, some geometry came from ACAD, most was generated in VW 11 for an exterior view, now I'm modifying it in 12 for an interior view.

I was have alot of trouble rendering it so I got some simpler chairs (its a large meeting room with loose seating), converted a light fixture I made from an extrude along path to 3-D polygons, got rid of all the geometry that wasn't in the view, purged the file, and I lowered the recursion level. So I'm not sure what exactly tiped the scale, but it seems to render OK now.

Another thing I was wondering is how do the linear lights work? They also seem to increase the rendering time, and on some older machines it makes them unusable. Is this normal?

Thanks

[Dave_Donley]

Line lights are similar to area lights, in that multiple light sources are automatically created along the light's geometry. Many more samples can end up being used than with a simple light type like point lights, for example.

Area and line lights render slower when there are reflective surfaces in the model, like Phong, Mirror, Glass, etc. Line and area lights can render faster with radiosity than with raytracing, and usually render fastest with radiosity and minimal reflective textures.

An extrude along path should be OK, it is usually better to keep geometry as high-level as possible for as long as possible, versus converting it to simple lower-level types of geometry. Radiosity especially works better with extrudes along path versus tiny 3D polygons. Reducing the geometry load, the number of pixels, and the cost-per-pixel (like with reflective surfaces and recursion levels) is the name of the game.

HTH,

Dave Donley

dave@nemetschek.net

Edited November 10, 2006 by Dave_Donley_At_Home

[islandmon]

Reducing the geometry load, the number of pixels, and the cost-per-pixel (like with reflective surfaces and recursion levels) is the name of the game.

And by all means use 'high-level' Symbols and Image Prop Symbols ...

Symbols are one of the most efficient ways to efficiently decrease file size and render time.