export data from one shader to another

[mic]

hello! i have written two shaders - displacement and surface. both of them similarly calculates new 's' and 't' coordinates. I think it would be better to calculate uv space only in the displacement shader and then export the values to surface, it would be faster. can i do this?

(shaders written in rsl)

[Mario Marengo]

hello! i have written two shaders - displacement and surface. both of them similarly calculates new 's' and 't' coordinates. I think it would be better to calculate uv space only in the displacement shader and then export the values to surface, it would be faster. can i do this?

(shaders written in rsl)

In RSL, you can combine displacement and shading in a single surface shader, so you're not forced to use message passing. You can still choose to write them separately if you wish, of course. In that case, you can import the st's from a displacement shader (which exports them) using the displacement() function. The import functions are (from the help):

float atmosphere( string param; {float|point|color|string} var )
float displacement( string param; {float|point|color|string} var )
float lightsource( string param; {float|point|color|string} var )
float surface( string param; {float|point|color|string} var )

And their VEX analogs:

int dimport(string name; {int|float|vector|vector4|matrix|matrix3|string} value&)
int limport(string name; {int|float|vector|vector4|matrix|matrix3|string} value&)
int simport(string name; {int|float|vector|vector4|matrix|matrix3|string} value&)
int shimport(string name; {int|float|vector|vector4|matrix|matrix3|string} value&)

Cheers.

[mic]

thanks a lot, i'll try!