> Somewhat inversely, I'm also wondering if a simple texture1D() lookup might > not be faster than evaluating the light function e / pow((1.0 + a * exp(-b * > (x-c)) ),(1.0/d)) three times to get an (rgb)-triplet.
That depends a lot on the GPU, and how coherent the texture coordinates are across a triangle. You also need enough ALU work elsewhere in the shader to mask the latency of the texture lookup. For the existing noise texture generation, take a look at make3DNoiseImage in scene/material/TextureBuilder.cxx in the simgear tree. This particular texture is filled CPU-side, but if you're more comfortable expressing things in a shader, you/someone could rig up some FBO wiring to quickly render a shader-defined function into a texture. -- Chris ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
