Does CA3DE use texture compression?

Get help with installing and running the Cafu Engine here. This forum is also for general questions and discussion of all aspects regarding the Cafu Engine.
Post Reply
scott
Posts: 173
Joined: 2004-08-23, 09:11

Does CA3DE use texture compression?

Post by scott » 2004-09-29, 09:09

I just noticed you guys are using nothing but png format for your textures, is this because ca3de doesnt have texture compression? I use bitmaps and they run rather slow, my vidcard is a bit too wussy to handle uncompressed materials. This may explain why ca3de doesnt run as smooth as it should for me :)
User avatar
Carsten
Site Admin
Posts: 2169
Joined: 2004-08-19, 13:46
Location: Germany
Contact:

Re: Does CA3DE use texture compression?

Post by Carsten » 2004-09-29, 11:21

scott wrote:I just noticed you guys are using nothing but png format for your textures, is this because ca3de doesnt have texture compression?
Texture storage and compression for texture files (e.g. png) and texture compression on the video board are not necessarily related to each other.

Ca3DE does support .bmp, .tga and .png image file formats (and probably .jpg in the future). Among those, .jpeg and .png are compressed formats. But no matter in which of these file formats the image is stored, the engine sees an uncompressed image after loading.
The image is always (but see (1)) passed in uncompressed format to the graphics board, which may or may not use texture compression to store the image in video memory. That is, the graphics driver may re-compress the texture into a proprietary format before putting it into video memory.

Unfortunately, you're right: Ca3DE does NOT yet support texture compression - the video board is never asked to re-compress the images before putting them into video memory. As soon as the MatSys is finished, I'll add support for such compression.

However, as explained above, that does not imply any changes about the file format that is used to store image files on disk. I prefer .png simply because it provides high compression and is a loss-less compression method. Even after I added texture compression to Ca3DE, we will stay with .png etc. files, the only difference is that the OpenGL driver will be asked to re-compress the texture images before storing them in GPU memory.

(1) Images can also be stored on disk and passed to the OpenGL driver directly in a compressed format, such that there is no need for uncompressing .png and .jpeg, and to then re-compress them in the driver. However, all these compression formats are currently vendor specific, and thus it does not make much sense to use them.
This may explain why ca3de doesnt run as smooth as it should for me :)
Already read this? ;)
Best regards,
Carsten
scott
Posts: 173
Joined: 2004-08-23, 09:11

Post by scott » 2004-09-29, 12:17

Thanks for the info carsten :)
Post Reply

Who is online

Users browsing this forum: No registered users and 3 guests