salam evryone i tried evry way i know to get clean result as in maya and max to creat a laser ray from curve but know way , shader proplem writing , so if anyone know some setting it will be welcome , help please , i need to do a work with laser ray…………..

This may not be exactly what you're looking for as its not in Houdini, but I posted a question a few weeks back about making things glow for magic based fx. The general consensus seemed to be that for things that require a glow (like magic or your laser beams) the way to go is to do it in post.

Like I said, this is not technically an answer to what you're asking as its not in Houdini, but simply rendering out your laser beam with a constant white shader and then taking it into Nuke and using the lightwrap node on it will do the trick nicely and in almost real time. Glow effects in render is expensive and in-flexible. If it has to be done in Houdini, the advice given to me was to generate a volume around the object and then turn the object into a geometry light (the new light type in H11). However as I mentioned, this is not a fast render and adding glow in post is so much quicker and more flexible.

may be you didn't understamnd me , i want to a laser in houdini , modeling and rendering and all in houdini .
how to do laser in post can you attach a little hip file……?

Sure, you can make laser in post, its the only right way. 1)Just make curve in houdini 2) add “width” point attribute 3)Make simple constant shader(or use existing one) 4) Render it 5) Apply glow anywhere(right in houdini comp or nuke or…………)