Sign in to follow this  
CDProp

Texture size & performance.

Recommended Posts

With Mip-Mapping, is texture size less of an issue? Could I use 4096x4096 textures for everything, even objects as small as a pocket watch, and then count on the GPU to use a smaller Mip-level wherever needed?

Share this post


Link to post
Share on other sites
I forgot to thank you for your help. Thanks!

I've heard that some textures can be stored in compressed format in video RAM, and used directly by the card without having to be decompressed. Does anyone have any information on this?

Share this post


Link to post
Share on other sites
There's an overview of the technology on Wikipedia.

Microsoft's DDS texture format supports images compressed with these algorithms, and can pass them directly to the graphics card. It's possible to load DDS files manually in an OpenGL program and pass the compressed data to the card as well, though I can't fill you in on the specifics :/

There might be some examples on the NVidia or ATI websites of how to use these texture formats in GL, I assume there's some kind of GL extention for it.

Share this post


Link to post
Share on other sites
Use DevIL to load the DDS texture.
The extensions are GL_ARB_texture_compression and GL_EXT_texture_compression_s3tc and you would use glCompressedTexImage2D to create the texture.
Let me know if you have any questions.

Share this post


Link to post
Share on other sites
What are the advantages to using a DDS file? What _IS_ a DDS file for that matter? I have a plugin for photoshop that allows me to import the DDS file and it just looks like a bitmap with an alpha channel to me.

So can someone enlighten me on why I might want to use a DDS for a texture over a Bitmap?

Finally, I have another noob question here: what is Mip-mapping?

Share this post


Link to post
Share on other sites
DDS: http://translate.google.com/translate?hl=de&sl=de&tl=en&u=http://wiki.delphigl.com/index.php/DDS

MipMaps: http://translate.google.com/translate?u=http://wiki.delphigl.com/index.php/MipMaps&sl=de&tl=en&hl=&ie=UTF-8

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

Sign in to follow this