|
Author
|
Topic: Compressed tif textures
|
Yardstick
Pilot
|
posted 03-15- 10:20 AM
   
Here's something I was wondering about. Does a tif texture that has been compressed in a par file or just in its relevant directory and then loaded into the SDOE texture cache, take up less video memory than one that is simply uncompressed and loaded into texture cache? I have noticed that if I import compressed tifs into Paintshop Pro they are in 256 colour (well if not 256 certainly lower than my 16 or 32 bit). Is this reflected in the video memory usage?------------------
Yardstick painted this
 IP: Logged |
Bryan Russell
Pilot
|
posted 03-15- 05:30 PM
The tiffs are loaded into SDOE as 32 bit textures, i.e. RGBA 8888 (this means 4 lots of 8 bits  ). They are then converted to the format required for the video card, typically 16bit which may be 565, or 5551 etc, and then written to the texture cache in this format. So the answer is that no the tiff compression has no effect on texture memory. In fact, if you did make a 256 colour Tiff, the tiff loader would convert it to RGB 8888 as it loaded it anyway.The compression used by most of the Tifs in SDOE is the zip compression, which is lossless, just like a zip file of exe's or something. Tiff also supports other types of compression that are lossy, for example it supports the JPG compression format as well. As far as I know, PSP does not support zip compression on tiffs, so it is possible that you are loading jpg compressed textures with some image degradation. ------------------
Wings with Wires Go here for info about the Unofficial Patch IP: Logged |
Yardstick
Pilot
|
posted 03-15- 05:51 PM
I use Irfanview to load the images and copy and paste from there into PSP, so this is where the degredation must come from. Thanks for the info Bryan.IP: Logged | |
FSIC Messageboard
UBBFriend: Email This Page to Someone! 
