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Re: Texturemapping to gl_points



Thanks to all but well... particle system is exactly what I am doing :)
I need to project texture over 100k particles with 60 fps. It works so far nicely but the problem is that all texels for single point are colored from single pixel color from texture.
I remember seeing somewhere that it should be possible with some simple glTextEnvf() or similar setting.




Kent Miller kirjoitti 30.5.2008 kello 18:39:

Point sprites do this.

I would just look at using quads. I don't think there is much advantage to point sprites unless you are doing something like a particle system with thousands of points in which case point sprites can take your vertex data rate down. GL Points have their own special set of quirks.

Kent

On May 30, 2008, at 8:30 AM, Mike wrote:

I am mapping texture to GL_POINT.
My point size varies but lets say it's 5x5 pixels. Currently the whole point just samples single pixel from texture and point's texels are all that same color.


How can I (or can I) map it so that it all texels in point are sampled (1:1) from texture? i.e. if texture is 100 x 100px and point is 25x25px (not smoothed) the point should represent 1/4 region of texture and with 4 points I could represent whole texture.

Thanks.

-Mike


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References: 
 >How to load imagefile for texture (Leopard) (From: "Mike mcFin" <email@hidden>)
 >Re: How to load imagefile for texture (Leopard) (From: Jean-Francois Roy <email@hidden>)
 >Texturemapping to gl_points (From: Mike <email@hidden>)
 >Re: Texturemapping to gl_points (From: Kent Miller <email@hidden>)



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