point smoothing slooow!

[andras]

My app usually runs using approx 8% of the CPU. If I enable GL_POINT_SMOOTH, and render a couple points, the CPU goes to 100% and the FPS drops by 40%. If I render some lines too, then basically I'm in a software renderer path with 1FPS (note that I did not enable line smoothing!). Even if I just enable/disable point smoothing, and don't actually render any points, CPU usage goes up by 30%!

All this on a GF6600 with 78.01

[dorbie]

It may be a combination of things like your pointsize too but it doesn't entirely surprise me. Antialiased lines and perhaps points are (were) positioned as a DCC feature (professional digital content creation) for the more expensive Quadro range of cards.

You could try point sprites as a better option for a game card and load a nice round antialiased texture you may also desire the projective scaling of that sprite.

[Michoo]

glHint(GL_POINT_SMOOTH_HINT, GL_FASTEST);
glHint(GL_LINE_SMOOTH_HINT, GL_FASTEST);
//or GL_DONT_CARE

in init function should help.

[dorbie]

I doubt it, they're hints for a reason.

[Jackis]

I know one isuue about point smoothing and fragment programs.
If you enable point smooth and draw points with fragment program enabled (this is strange, I know, points with fragment program, :) , then GL falls to software mode.

[SeskaPeel]

We experienced precisely the same problem.

It's a shame, we'll have to recode manually what this option does (renderings 3 pixels * 3 pixels ortho aligned quads with alpha blending).

I had a lot of mails with dev rel at nVidia ... and they couldn't tell me why it behaved this way.

SeskaPeel.

[andras]

hmm, that would explain it, as that's exactly what I do too. I don't use the fixed function pipeline at all, everything uses fragment and vertex shaders.
i guess in the end we'll just use point sprites anyway...