flexible domain for image sampler

Replies to This Discussion

Permalink Reply by Danny Boyes on March 19, 2012 at 3:56am

Use the ReMap component to change your range to a 0 to 1 domain before the Image Sampler.

The T (target domain) input is 0 to 1 by default

Permalink Reply by Jens Pedersen on March 19, 2012 at 3:59am

Are you sure that will work for points? you know since the image sampler ask for points not a numerical domain?

Because the problem is not to remap/reparametrize a numercial domain, but to make the working domain of the image sampler to scale as you scale the spacing between your points... so in a sense the problem is not so much on how to deal with domains, but how to make the image smapler understand when you change the size/domain/whatever you want to call it for your point grid...

Permalink Reply by Danny Boyes on March 19, 2012 at 4:14am

Its important to understand that you are using the XYZ component to create a 2 dimensional list not a point list. You are using it to get a (u,v) list or (a,b) etc.

Permalink Reply by Jens Pedersen on March 19, 2012 at 4:30am

ahhh okay... thank you very much... This is just my first time to mess around with the image smapler component, and I am having a little trouble wrapping my head around it...

Permalink Reply by Danny Boyes on March 19, 2012 at 4:35am

I find the best way to use the image sampler first time around is to:

1) insert a Picture Frame of your chosen image into Rhino.

2) Reference Surface from Rhino.

3) Reparameterise the Referenced Surface.

4) Use the SDivide Component to generate you Points.

5) Use the UV output of the SDivide component

6) Have the Image sampler Domain as 0 to 1.

This approach allows you to apply your "Manipulation" directly to the SDivide points so that you can see what is happening in the Rhino Document on top of your chosen image.. This quickly highlights any irregular or unexpected behaviour.

Permalink Reply by Jens Pedersen on March 19, 2012 at 4:36am

cool thanks for the tip!

Permalink Reply by Pep Tornabell on March 19, 2014 at 4:36am

thanks! 

:)

Permalink Reply by ian bake on April 7, 2012 at 9:56am

hi, do you have any idea on how to map a image sampler onto a 3d surface? i have a points based on centrepoints of trangles. I want to use these centre points to be based on a image sampler from ecotect to determine the radius of the circle. My surface however is 3d.

Permalink Reply by ian bake on April 7, 2012 at 11:37am

i figured it out if anybody is interested. I used [Surface CP] obtain the UV values based on the inputs of Points and Surface. The uv values is then fed into image sampler. The circles created then can be adjusted to the normal of the surface through [evaluate surface] component. Oh, and ensure that the domain of the image sampler has the same values as the grid size. Or, you can just change the domain as what danny did above. =)

Permalink Reply by Ole on March 21, 2019 at 12:05pm

As a newbie to Grasshopper, I found this thread quite useful and I thought I had a little bit to add.

I wanted to be able to tile and offset the image, as well as have the points grid remain a static size. This way the data from the image sampler can be controlled separately from the points. 

imagesampler_working.gh

UV_map.jpg