Hi Sherman, On 10/16/07, sherman wilcox <[EMAIL PROTECTED]> wrote: > See attached.
Thanks for he example, I can see the shimmering effect. The artifact kinda looks like texture minification/aliasing issue - but just as easily could be a straight precision issue on the computation of the corners of the quads for each character. The big question is.. which might it be... I tried altering the font resolution size but this didn't affect the shimmering which I would have expected at a bit of difference if the issue was a mipmap quality issue. However, this basic test can't rule it out as a possibility. The mipmaps for text are computed using the hardware mipmap extension where supported (its support by most modern hardware), the quality won't be the best attainable if done is software though. While I can't rule texture aliasing as an issue this out yet, it probably makes sense to look at the next likely contender... precision. The code Text::computePositions found in src/osg/Text.cpp does compute the matrix in doubles which is good, but it does a transform of the corners of the character quads which will be in floats, and if the position has a large offset - as is the case in this example then precision will be an issue for objects that are near to each other. Placing a MatrixTransform over each text object to position should help in this situation, with the transform of the quad corners done with a local origin. The other alternative is to put this transform directly inside the text object to provide the large position support. Robert. _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
