hey!

sounds interresting, but not sure it will actually improve performance,
where in the article do you get lost?

anyways, on my computer i get these performance results for drawing 15000 lines
crappy intel card:
- with GL_LINE_SMOOTH: 14..16 fps
- without: 17..18 fps
nvidia 330:
- with GL_LINE_SMOOTH: 49...53 fps
- without: 49...52 fps
     
so even if you could smoothen out the lines without any time cost, you wouldn't gain much  (at least not in on my computer)

here's the code i used to test:

1. int num = 15000;
   import processing.opengl.*;
   import javax.media.opengl.*;
   
   void setup(){
     size( 800, 600, OPENGL );
     frameRate( 60 );
     ((PGraphicsOpenGL)g).gl.glEnable (GL.GL_LINE_SMOOTH);
   }
   
   
   void draw(){
     background( 0 );
     stroke( 255, 10 );
     for( int i = 0; i < 15000; i++ ){
       line( random(width), random(height), random(width), random(height) );
     }
    
     if( frameCount % 10 == 0 ) println( frameRate );
   }

how do you currently draw the lines? have you tried using vertex arrays, display lists, framebuffer objects?
might be a better place to start optimizing!

that is a very bad way to render big amount ofof lines (specially if is not all about the lines), still a good test. using better ways should make fps go higher alot yes. i think what jeef wants is better way (not really on performance) to render lines, as in anti-aliased lines. thats the reason for that article.. i once said i would try that article but just never got the time to test it.. ill see if i can do it this summer and i will report back to u jeff

Victor MARTINS
www.pixelnerve.com

p.s. sorry, didn't read your reply properly.
think we're actually on the same page, performance improvement most likely no,
prettyness improvement definitely yes.

The current performance on my graph goes something like this... Using a VBO for the lines

18,000 lines (blending with a certain level of alpha)
GL.GL_LINE_SMOOTH runs me about 20-30 fps
turning off GL.GL_LINE_SMOOTH - runs me about 90-100fps
turning off the lines, and running the rest of my sketch 16,000 multitextured point sprites vbo, 650-700 fps.

Of course, if I can maintain quality while increasing performance, I'd love to do that.  I'm not sure why a line takes so much juice, while the textured objects take very little.

I'm familiar with creating a glsl shader, and could probably post that part of the example.  I think tough part for me would be the CPU portion of the article.

Late to the party, but: I was the editor of the cited article.

You won't probably gain perf except in very artificial circumstances.

Quality, yes. But perf, no. And worse, you need to sort.

But qualtiy: yes.


kb, http://www.riftgame.com/