how to choose between depthmap shadow and raytrace?

Become a member of the CGSociety

Connect, Share, and Learn with our Large Growing CG Art Community. It's Free!

Thread Tools Search this Thread Display Modes
  09 September 2012
how to choose between depthmap shadow and raytrace?

Is there any common or specific reasons, when you choose between depthmap shadows and ray trace?
  09 September 2012
Generally speaking, depthmap is faster. While raytrace is more accurate. Some raytrace renderers do not support depthmap (such as vray) so in that case raytrace shadow will be your only choice.
  09 September 2012
Historically speaking, when CG was in it's infancy - raytracing was slow and memory intensive, so depth maps were used as a practical workaround. Although things have changed in the last few years - aside from a few exceptions (hair/fur being the main one) - most shadows are calculated using raytracing, even when using PRMan or 3Delight.

The main benefit of depth-map shadows is that you could store and re-use the shadow calculation. This could save you time when lighting or re-rendering - as long as the animation or the light position didn't change you didn't need to redo the shadows. For static lights you could also calculate the shadows on one frame and re-use it through an animation. You could also things such as blur the shadow map to create soft-shadow effects.

The downside of this is that you had to manage an additional set of data in order to get the most use out of depth-map shadows.
  09 September 2012
thanks alot
  09 September 2012
Thread automatically closed

This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.
CGTalk Policy/Legalities
Note that as CGTalk Members, you agree to the terms and conditions of using this website.
Thread Closed share thread

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Society of Digital Artists

Powered by vBulletin
Copyright 2000 - 2006,
Jelsoft Enterprises Ltd.
Minimize Ads
Forum Jump

All times are GMT. The time now is 09:02 AM.

Powered by vBulletin
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.