Hi there, I’m doing a little experiment where I’d like to do texture lookups on axis-aligned, square POT images by specifying directly the mip level that I want sampled but I wouldn’t want to miss out on the benefit of TextureSys doing the blending between two mip levels, so doing an ImageCache lookup with a explicit mip level doesn’t seem appealing to me.
From reading the docs and having a quick look at the headers & source it looks like the derivatives always need to be specified but unfortunately as my use case is fairly different from the general rendering use cases I don’t have derivatives to start with. Is there a quick way to apply the reverse formula? it looks like ellipse_axes() calculates the lengths (in my case should be the same) and in turn compute_miplevels() uses these to get the actual mip level used, I guess I can’t bypass these steps so I was wondering if there is anything that I’m missing, any obvious way to turn my mip level number into something sensible that could be used to do the TextureSys::texture() call. Btw, this is my first email to the list so I’d like to say thanks a lot for this amazing library, it’s great being able to use it everywhere (including iOS!) Cheers, -Javier _______________________________________________ Oiio-dev mailing list [email protected] http://lists.openimageio.org/listinfo.cgi/oiio-dev-openimageio.org
