DDS Mipmaps and LOD
by ChrisG · in Artist Corner · 09/04/2008 (6:19 pm) · 3 replies
We've recently decided to move development of our game ZDay from TGE over TGEA.
Due to the ZDay map allowing the player to see many buildings at once we discovered that out greatest performance hit was coming from the many textures that were loaded (textures were filling up 1Gb of RAM), so we LODed all the buildings and created lower-res jpeg textures for all the lods. This greatly improved things.
While the poly count dropped in each successive LOD it was reducing the texture sizes in the lods that had the greatest impact.
Now that we're moving to TGEA I'm finding out about DDS texture format and the fact that it can create and store mipmaps when exported from photoshop
So the questions are these:
1. Do we still need to create lower-res textures for the DIF LODs or will the DDS textures take care of this?
2. Does having more mipmaps in a DDS improve performance?
3. When exporting DDS using NVidia DDS exporter should I just set generate mipmaps to 'All' or would another value be better?
Due to the ZDay map allowing the player to see many buildings at once we discovered that out greatest performance hit was coming from the many textures that were loaded (textures were filling up 1Gb of RAM), so we LODed all the buildings and created lower-res jpeg textures for all the lods. This greatly improved things.
While the poly count dropped in each successive LOD it was reducing the texture sizes in the lods that had the greatest impact.
Now that we're moving to TGEA I'm finding out about DDS texture format and the fact that it can create and store mipmaps when exported from photoshop
So the questions are these:
1. Do we still need to create lower-res textures for the DIF LODs or will the DDS textures take care of this?
2. Does having more mipmaps in a DDS improve performance?
3. When exporting DDS using NVidia DDS exporter should I just set generate mipmaps to 'All' or would another value be better?
About the author
Currently working on ZDay: www.zdaygame.com
#2
- more mipmaps = better performance but less detail at distance
- fewer mipmaps with tweaking of settings in Torque = better detail at distance but lower performance
- no mipmaps = worse performance and detail
but is 'All' too many mipmaps?
09/04/2008 (7:53 pm)
Yeah I did read that, from what I gathered (please correct me if I'm wrong) is that:- more mipmaps = better performance but less detail at distance
- fewer mipmaps with tweaking of settings in Torque = better detail at distance but lower performance
- no mipmaps = worse performance and detail
but is 'All' too many mipmaps?
#3
No mipmaps on a DDS looks awful - like your whole game world is filtered with some sort of sharpen unmask. It hurt my eyes when I tested it. Without DDS format (jpg, png) I think Torque seems to decide for itself how mipmaps work, which I found a bit overly blurry. That goes for using ALL mipmaps too.
09/05/2008 (6:20 am)
I found things seem to look fine with 4 mipmaps (my textures are only 512 though). As for performance I guess it depends on your PC, I can't say I've noticed any difference - but you should always bear in mind people with lower spec computers playing your game. I'm no-where near having to worry about optimizing my personal project for multiple specs yet, though I have been thinking about it.No mipmaps on a DDS looks awful - like your whole game world is filtered with some sort of sharpen unmask. It hurt my eyes when I tested it. Without DDS format (jpg, png) I think Torque seems to decide for itself how mipmaps work, which I found a bit overly blurry. That goes for using ALL mipmaps too.
Associate Steve Acaster
[YorkshireRifles]
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