   HLSL static?
  I'm playing around in renderMonkey (ATI's HLSL shader environment) trying to come up with some usable shaders...I hope it's ok to ask two rather seperate quesions:(scenerio 1)For an animated cloud shader, I'd like to be able to store some "static" type data (variables which retain their value from frame to frame) but may also be *updated* frame to frame.  This value is independant of any item's position, the frame rate, etc.  I'd like to perform a brownian (random) 2d walk.I can't seem to find a way to do this...question 2:I'd like to write to textures (I assume a renderable target would be fastest for this?) using something which could resemble (at least in functionality) the tight for y ... for x ... type 2d loop (I'd like to write to every pixel)This sort of thing is easy to do on the CPU; is the CPU the only way to go?If, for instance, I wanted to calculate the values for a volume, perlin noise texture, (or a 2d perlin noise texture), if I have perlin noise implemented in a pixel shader, is there some way to write the data once? or every xxx frames? or every x seconds?Should I really move outside the scope of renderMonkey to write these kinds of effects?Thanks in advance,-Michael g.   