Eric,

You should look at your TexEnv parameters.  Use something like DECAL or 
REPLACE.  Looks like you are using the default, which is MODULATE, which takes 
into account the color of the polygon with the texture.  Of course these modes 
(DECAL,REPLACE) will disable any lighting that is going on, but you seem to 
want that anyway.

HTH
--
Chuck

On Feb 16, 2011, at 12:42 PM, Eric Sokolowsky wrote:

> Jason,
> 
> Thanks for the suggestion. I did re-render the image at twice the size but 
> I'm still seeing that the textured polygon version is noticeably dimmer than 
> the DrawPixels version. See the attached image. I have three images here, 
> each rendered twice, the top drawn with the textured polygon and the bottom 
> rendered with DrawPixels. I'm not doing any enlargement now. Any ideas on why 
> the DrawPixels version so much brighter than the textured polygon?
> 
> -Eric
> 
> On Wed, Feb 16, 2011 at 11:35 AM, Jason Daly <[email protected]> wrote:
> On 02/16/2011 10:44 AM, Eric Sokolowsky wrote:
> Hello,
> 
> 
> Does anyone have suggestions on getting the textured version brighter, 
> hopefully as bright as the DrawPixels version?
> 
> The textured version is probably getting dimmer because of the linear 
> magnification filter.  Since your background is black, any pixels in the 
> image that are partially covering a pixel on the screen are getting mixed 
> with the black background and the overall luminance is lessened because of 
> that.  The DrawPixels version is obviously blocky because you're drawing 
> without any kind of magnification filter.  If you switched the mag filter 
> settings on the texture version to GL_NEAREST instead of GL_LINEAR, I imagine 
> your results will look very much like the DrawPixels version.
> 
> Of course, the real problems is that you're rendering the given image to a 
> resolution that is significantly larger than its actual size.  Ideally, you'd 
> want to enlarge the original image to as close to the target resolution as 
> you can before using the texturing operations to draw it to the screen.  I 
> don't know the source of the image, so I don't know if it's possible or 
> practical to do this, but that would be the best solution.
> 
> --"J"
> _______________________________________________
> osg-users mailing list
> [email protected]
> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
> 
> <out-2.png>_______________________________________________
> osg-users mailing list
> [email protected]
> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org

_______________________________________________
osg-users mailing list
[email protected]
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org

Reply via email to