Feature Request: How Do I Use VT's?

General discussion about Celestia that doesn't fit into other forums.
Topic author
Bob Hegwood
Posts: 1048
Joined: 19.10.2003
With us: 21 years
Location: Germantown, Ohio - USA

Post #61by Bob Hegwood » 24.02.2004, 04:05

selden wrote:Here's an ImageMagick command that can be used to create a 1K image from an 8K image:

Code: Select all

convert -geometry 1024x512! Mars8k.jpg Mars1k.jpg

(The exclamation-point forces "convert" to generate an image of exactly that size. Without the exclamation-point, sometimes it'll decide to create an image that's off by 1 pixel in one of its dimensions. As you know, Celestia doesn't like that at all! )


Well Hell...

I didn't know all of this. Why didn't YOU guys write the instructions? :roll:

Thanks (I Think!) :wink:

Take care, Bob
Bob Hegwood
Windows XP-SP2, 256Meg 1024x768 Resolution
Intel Celeron 1400 MHz CPU
Intel 82815 Graphics Controller
OpenGL Version: 1.1.2 - Build 4.13.01.3196
Celestia 1.4.0 Pre6 FT1

Topic author
Bob Hegwood
Posts: 1048
Joined: 19.10.2003
With us: 21 years
Location: Germantown, Ohio - USA

Post #62by Bob Hegwood » 24.02.2004, 04:10

chris wrote:
Toti wrote:I prefer JPGs because of my limited RAM
JPGs are indeed decompressed at load time, so once they've been loaded, you realize no benefits from the decompression.

Like I said...

Maybe YOU guys should have written the documentation. :wink:

Hell, I didn't know. <shrug>

If I understand you correctly, then... I should *never* convert an image map from the DDS format to jpg. Yes?

Take care, Bob
Bob Hegwood

Windows XP-SP2, 256Meg 1024x768 Resolution

Intel Celeron 1400 MHz CPU

Intel 82815 Graphics Controller

OpenGL Version: 1.1.2 - Build 4.13.01.3196

Celestia 1.4.0 Pre6 FT1

Toti
Developer
Posts: 338
Joined: 10.02.2004
With us: 20 years 9 months

Post #63by Toti » 24.02.2004, 04:32

Bob Hegwood wrote:
Toti wrote:
VirtualTexture
{
ImageDirectory "EarthHires"
BaseSplit 0
TileSize 256
TileType "jpg"
}

It is TileSize 512 (because you create 2 512*512 textures)

Toti,

The TileSize 256 was set to 256 after I read Mr. Ball's advice on how to make the display work more smoothly. I don't remember where I read it, but I know that Selden said to do that.

I know the Tiles are 512 pixels wide.


Oh, forgive me. I was not sure about it being the smooth trick, or a mistake.
Perhaps you should include a statement in your instructions explaining the usual TileSize arrangement and the modified one for display smoothing.

Anyway, your instructions DO work :)

Bye

Topic author
Bob Hegwood
Posts: 1048
Joined: 19.10.2003
With us: 21 years
Location: Germantown, Ohio - USA

Post #64by Bob Hegwood » 24.02.2004, 04:40

Sorry Toti...

I didn't mean to sound as if I were a "Grumpy Old Man." Come to think of it though, I am a grumpy old man. What the hell. :wink:

All I can do is thank you once again for all of your excellent advice. If it hadn't been for your assistance, I *still* wouldn't know what a Virtual Texture is.

Of course, it seems that my education is still lacking in places, so I'll go back and see what else I can learn.

Thanks again Friend. -Bob
Bob Hegwood

Windows XP-SP2, 256Meg 1024x768 Resolution

Intel Celeron 1400 MHz CPU

Intel 82815 Graphics Controller

OpenGL Version: 1.1.2 - Build 4.13.01.3196

Celestia 1.4.0 Pre6 FT1

Topic author
Bob Hegwood
Posts: 1048
Joined: 19.10.2003
With us: 21 years
Location: Germantown, Ohio - USA

Post #65by Bob Hegwood » 24.02.2004, 07:08

To Selden, Toti and Chris...

I have updated "Virtual Textures For Dummies" on my website. It now includes the things you discussed here earlier tonight.

Thanks for the advice. To Selden - Now it's 9 pages! :lol:

Take care, Bob
Bob Hegwood

Windows XP-SP2, 256Meg 1024x768 Resolution

Intel Celeron 1400 MHz CPU

Intel 82815 Graphics Controller

OpenGL Version: 1.1.2 - Build 4.13.01.3196

Celestia 1.4.0 Pre6 FT1

Harry
Posts: 559
Joined: 05.09.2003
With us: 21 years 2 months
Location: Germany

Post #66by Harry » 24.02.2004, 09:51

Bob Hegwood wrote:If I understand you correctly, then... I should *never* convert an image map from the DDS format to jpg. Yes?

DDS must be supported by your graphics card (or in your case the integrated graphics solution), so older hardware won't show DDS textures at all. DDS is unsuitable for normalmaps, because it results in blocky images. Finally JPG has smaller filesizes and is a better choise if you are low on diskspace or want to offer a texture for download.

Harald

Harry
Posts: 559
Joined: 05.09.2003
With us: 21 years 2 months
Location: Germany

Post #67by Harry » 24.02.2004, 10:00

Bob Hegwood wrote:The TileSize 256 was set to 256 after I read Mr. Ball's advice on how to make the display work more smoothly. I don't remember where I read it, but I know that Selden said to do that.

You may want to add a note that there is a huge performance hit when going from TileSize 512 to TileSize 256, because Celestia loads tiles much earlier and has to keep many more tiles in memory.

Harald

Topic author
Bob Hegwood
Posts: 1048
Joined: 19.10.2003
With us: 21 years
Location: Germantown, Ohio - USA

Post #68by Bob Hegwood » 24.02.2004, 17:56

Harry wrote:You may want to add a note that there is a huge performance hit when going from TileSize 512 to TileSize 256, because Celestia loads tiles much earlier and has to keep many more tiles in memory.


Okay, thanks Harald...

I'll play around with it a bit, and see what effect it actually has on my machine. I haven't really noticed any degradation in performance though. :wink:

Take care, Bob.
Bob Hegwood

Windows XP-SP2, 256Meg 1024x768 Resolution

Intel Celeron 1400 MHz CPU

Intel 82815 Graphics Controller

OpenGL Version: 1.1.2 - Build 4.13.01.3196

Celestia 1.4.0 Pre6 FT1

Guest

Post #69by Guest » 31.08.2004, 11:36

when i try and get a picture that is 8k or more and i convert it to tiles with virtualtex i can only get 83 tiles done then it does some error...
i edited the virtualtex with wordpad and change maxmem=80 to maxmem=200 and that seemed to do the trick. did anyone else have this problem? i was a bit worryed at one stage :) and why doent it have that settings in the start?


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