Colour assign to gemoetry

Hello there.

I'm trying to create a definition that will assign a specif colour to a given geometry. By, lets say, distance to point (similar to an attractor point definition). But I don't know how to tell GH to pick a colour. Can I use the image component...?

Any ideas

thank you all

Replies to This Discussion

Permalink Reply by Vicente Soler on October 7, 2009 at 8:14am

Use the Gradient component under Params -> Special

Permalink Reply by Damien Alomar on October 7, 2009 at 8:19am

Colors are just numbers... numbers from either 0-255 or 0-1 for the Red, Green, and Blue channels. The "easiest" way to generate colors is from a vector, which you can either break down manually, or simply pass to a shader as you would a color.

Here's a really simple example. Just take two points, make a vector and a line between them. Unitize the vector and pass that to a shader, then use the geometry preview. The line should change color as you move the points around.

Permalink Reply by Claudio on October 7, 2009 at 9:28am

wow I'll give it a try thank you

Permalink Reply by oliver von Malm on October 7, 2009 at 11:51am

nice, but where do you find this kind of shader? and is there a way to render with these shaders? can you import any other like mentalray or vray materials?

Permalink Reply by David Rutten on October 7, 2009 at 2:47pm

The Shader parameter allows you to pick an existing material from the Rhino material table (you need to have the RDK installed though in order to get this feature).

You cannot import shaders from mentalray or vray, it is only possible to display basic Rhino materials, and I don't support textures at all.

--
David Rutten
david@mcneel.com
Seattle, WA

Permalink Reply by David Rutten on October 7, 2009 at 2:46pm

Note that when you use the Vector -> Color inbuild conversion, the actual numeric range is -1.0 to +1.0.

X maps onto Red
Y maps onto Green
Z maps onto Blue

By picking the -1.0 to +1.0 range, it means that all unitized vectors (no matter where they are pointing) give you a unique colour.

--
David Rutten
david@mcneel.com
Seattle, WA

Permalink Reply by Vicente Soler on October 7, 2009 at 4:17pm

It would technically be stored as a unique color. But since a standard graphics card can only display 256 colors per channel and an LCD screen even less, in practical terms vectors with a difference of up to 0.007% could still share the same color.

Permalink Reply by Vicente Soler on October 7, 2009 at 4:01pm

As for what the the OP was actually asking, it would go something like this:

It would be better to substitute the attractor formula for one that doesen't tend to infinity.

Permalink Reply by Philipp on November 25, 2009 at 2:42pm

Hey, can anyone explain me how to render in rhino render using ghp sheyders?
is it possible to export sheyders to vray, flamingo, e.t.c. (maybe using exel eport?)

Permalink Reply by Dennnis on May 15, 2010 at 7:28am

Check this page half way down:
http://gracefulspoon.com/blog/tag/grasshopper/
Maybe this can help you..

Permalink Reply by Jaime Sànchez on April 15, 2016 at 1:25pm

Hi there!, i don´t know how threads work in the forum since i´m relatively new to the software, i am trying to achieve the definition you created, but i dont know many components by icon, is there any possible way you could share your definition with me?, i would greatly apreciate it, or at least show me a print screen with full names?, i want to get around at how does this work.

Best regards, Jaime.

Permalink Reply by David Rutten on April 15, 2016 at 3:14pm

Hi Jaime,

this is a terribly old thread. There have been so many changes since then it may be easier to start anew.