Dear all!!

I'm trying to get an expression in order to color randomly the particles in light brown, dark brown, very dark brown and a little bordeaux tints!
In the shader, I was trying to guess what kind of rand($PT) expression could work, but couldn't find any correct one!

to this picture, I would like to give a feeling of sand! what would be your advice!

Tx all

you will want to assign a point color attribute that is used as a tint in your shader.

try looking at the color pop.

tx Stephen!

try to lower the size of the sand ,add some specular, and some GI, and
for the sand color, try the color pop…..

Sorry to bother again! but I've seen the “blowing an image away using particles” tutorial!
The expressions used in the point sop of the color section are really great and very useful!!
But I need to use them for a picture which has an alpha!
I am just wondering if the expression would be the same if I add the alpha!
as:add alpha = pic(“../cop2net1/detour4_picnc”,$BBX,$BBZ,D_CA) ??
Thanks a lot for the help!!

You can do an exhelp in the textport:
exhelp pic
float pic (string copname, float U, float V, float color_type)
The color_type parameter can be one of the following: D_CR, D_CG,
D_CB, D_CA, D_CHUE, D_CSAT, D_CVAL, D_CLUM for the red, green, blue,
alpha, hue, saturation, value, or luminance of the pixel.

The color returned will be interpolated smoothly between adjacent
pixels. For the non-interpolated color, use picni.


EXAMPLES
| pic(“/img/img1/color1”, .5, .5, D_CLUM)
|

RELATED
* picni

* tex

* texni

* res


REPLACED BY
- hou.CopNode
Cheers!
steven

tx very much!!