Hi, I am seeing some strange behaviour with the DatabasePager and compressed textures (compressed using the nvtt image processor) and cant get my head around what is happening.
My setup is this: - A paged terrain very similar in nature to a VPB created terrain. - Images and height fields are stored in a database and read at runtime. As the db uses aggressive mem caching, many reads of 'files' are actually read straight from memory so images are loaded very quickly. To demonstrate the problem, I rapidly move the camera around the terrain to generate lots of database requests. If the textures are not compressed (or stored as jpegs etc, so they are not compressed once loaded) then the precompilation works perfectly and I get no frame drops. If I change the textures to use compressed dds images, I get terrible frame drops (down from completely solid 60hz to bellow 20). I figured something was going wrong with the precompiler but after much debugging this seems to be working as designed. If I set the max num of objects to compile to 1 then the problem is reduced, but this is obviously not a solution as it is just masking the problem. The only thing I can think of is that the precompiler isn't actually uploading / compiling the textures when they are compressed, but it is when they are not. As such, the precompilation stage races through lots of textures and then during the draw phase the actual work is done, causing the frame drops. However, I have no idea why this should be the case or how I could address issue. Has anyone come across this before or have any suggestions as to what might be going on? Cheers, Brad ------------------------------------------------------------------------- DISCLAIMER: This e-mail transmission and any documents, files and previous e-mail messages attached to it are private and confidential. They may contain proprietary or copyright material or information that is subject to legal professional privilege. They are for the use of the intended recipient only. Any unauthorised viewing, use, disclosure, copying, alteration, storage or distribution of, or reliance on, this message is strictly prohibited. No part may be reproduced, adapted or transmitted without the written permission of the owner. If you have received this transmission in error, or are not an authorised recipient, please immediately notify the sender by return email, delete this message and all copies from your e-mail system, and destroy any printed copies. Receipt by anyone other than the intended recipient should not be deemed a waiver of any privilege or protection. Thales Australia does not warrant or represent that this e-mail or any documents, files and previous e-mail messages attached are error or virus free. -------------------------------------------------------------------------
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