The JWS thread *LWJGL demos only*

I got a GL_ARB_fragment_program not supported, and thats on a GeForce 4200 Go, so you’re probably seeing the same.

Aha, yes I see that in the logs now I look. :’(

exellent demoes…

[quote]I got a GL_ARB_fragment_program not supported
[/quote]
Is this a driver thing, or is a GF4 just not capable of fragment programs?

[quote]Is this a driver thing, or is a GF4 just not capable of fragment programs?
[/quote]
Looks like a hardware thing:

http://www.delphi3d.net/hardware/extsupport.php?extension=GL_ARB_fragment_program

hmmm, so it looks like the Ti4200’s hw is uncapable of doing them so it’s emulated instead. So why can’t we use the emulation then?

'cos when you emulate pixel/fragment shaders, you have to emulate the entire pipeline, which is obviously dog slow.

Before the FX series was actually released, nVidia had a bunch of drivers that had it’s pipeline emulated as an option. It was only really for people wanting to experiment with bleeding edge stuff though, its not really usable for anything practical.

Although for that demo I’m sure it would be possible to re-write it with GeForce4 specific shaders, it’d just be a bit of a pain. :-[

Nice work JCD.

In reference to the FontFactory. A question. Since so many of the TT fonts aren’t fixed width, how do you subdivide the font texture into subtextures in a call list for us as a texture based font?

I’m new to GL and the application I’m fiddling with displays car traffic on a simulated top down street view. Each car has a small symbol with a data label attached to it with text data displayed. I’m using a self-created texture and subdividing it into a call list for use. Of course I’ve created a fixed width font which makes parsing quite easy.

However, I’m currently just using immediate mode for the drawing of the labels to screen, which includes potential color changes for some of the fields that make up a car’s label.

Whilest the data in the labels doesn’t change that often, however the location moves every few seconds as the car “moves”.

I would like to be able to smoothly simulate at least 2000 cars moving when I’m zoomed right out.

Question 1: Is there a performance difference between writing to a VBO/call-list/texture then sending that compared with using immediate mode?

Question 1b: Do you think it would be wise for me to write each individual label to a texture/vbo and just move it down the screen and recreate it when the data changes (car speed etc?), or would the performance gain not be significant enough to not just use immediate mode? Note that each label has a few rows of data (about 40 characters in all), generally one color, but with a few fields possibly another color.

Question 2: Behind the car display I require a street map (currently defined as geographical vertices). Would it be best for me to write these maps to textures (individual maps can be enabled/disabled), and add them to call lists for performance? Would this be better than drawing thousands of vertices every redraw?

Thanks for any advice you (and anyone else) might have.

FYI: I’m using J2SE1.5 and JOGL 1.0 (for now).

Regards,

Greg.

I wouldn’t think that VBO’s would gain you much, since the data changes constantly. Regular old vertex arrays would be an improvement over immediate mode though (and pretty simple as well).

[quote]Question 1b: Do you think it would be wise for me to write each individual label to a texture/vbo and just move it down the screen and recreate it when the data changes (car speed etc?),
[/quote]
No idea, it’d probably depend on how often they change, and whether you’ve got plenty of video ram for caching all the labels. It sounds like a lot of work though, why not try vertex arrays for drawing it and see how the performance is? Have you actually figured out that this is a bottleneck in your drawing?

[quote]Question 2: Behind the car display I require a street map (currently defined as geographical vertices). Would it be best for me to write these maps to textures (individual maps can be enabled/disabled), and add them to call lists for performance? Would this be better than drawing thousands of vertices every redraw?
[/quote]
Again, depends how often it changes. I assume a street map is fairly static, so writing it to a texture is probably a good idea. No need to shove the resulting texture+quad in a display list though.

I can’t get any of the Webstart demos to work. :frowning: :frowning:

They all say can’t load a jar file. Here’s a specific example from the blinn demo -


An error occurred while launching/running the application.

Title: Blinn Lighting & Particles
Vendor: Abdul Bezrati - Galactic Village
Category: Download Error

Unable to load resource: http://www.realityflux.com/abba/Lwjgl/BlinnLighting/BlinnLighting.jar

Any ideas?

Regards,
Aaron R>

Works fine for me (and I’d not downloaded them before), although they do then crash at the loading screen because of OGL errors.

I’m using java1.5beta2 as my jre. Do you suppose that this could be the problem?

Regards,
Aaron R>

I just switched back to jre 1.4.2 with JWS and all the demos start now.

Off to make a bug report. :confused:

Regards,
Aaron R>

Ahh crap, finally got around to buying a vid card that supports the pixel trickery and now all JCD’s demos have been taken down ::slight_smile:

Anyone know if all these demo are available on any other sites?

cheers all.