how to ray on surface in vex?

[trili]

Hi, will there any functions like Ray sop? Thanks!

[bunker]

yes, the "intersect" vex function does that:

 

vector p;
vector uvw;
vector raydir = normalize(chv("raydir"));
float raylength = chf("raylength");
int primfound = intersect(1,@P,raydir*raylength,p,uvw);
// copy primitive attribute from ray hit
@Cd=prim(1,"Cd",primfound);

 

[trili]

11 minutes ago, bunker said:

yes, the "intersect" vex function does that:

 

vector p;
vector uvw;
vector raydir = normalize(chv("raydir"));
float raylength = chf("raylength");
int primfound = intersect(1,@P,raydir*raylength,p,uvw);
// copy primitive attribute from ray hit
@Cd=prim(1,"Cd",primfound);

 

Thanks!