Changing default origin of Image Sampler

Hello,

I'm just learning to use grasshopper (recently watched the webinar), and I'd like to know how to change the origin of a bitmap sampler that is reading points from a Square Grid component. I am able to change the plane of the Square Grid, however the Image sampler seems to stay at (0,0,0) World.

What I'm hoping to accomplish is a perforated skin on a building using a black and white bit map to vary the perforations. Even when I set the C-plane to the face of my building and orient the Square Grid to it, the image seems to stay put (ie: and no longer influence the circle output)

What is the best way to accomplish this?

Thanks,

marc

Replies to This Discussion

Permalink Reply by Danny Boyes on August 11, 2011 at 9:06am

Not sure where or why you're going astray, so here is an example. (and some tips)

1) I always place the image that i'm sampling in Rhino as a Picture Frame so that I can see if things are going wrong

2) Reparameterise the Surface/Face you want to divide up

3) Use the UV of the SDivide component. That way it doesn't matter where the object is in the world it will always reference the image in relative terms.

4) use the default 0 to 1 domain of the image sample (hence reparameterising the Original Surface)

Note: If you are not going to reparameterise the referenced surface then make sure your image sampler domain is the same as the surface's.

Attachments:

imageSamplerDemo.gh, 15 KB

Permalink Reply by Michael Pryor on August 11, 2011 at 9:28am

I always seem to have a problem with the image sampler. I use surface frames instead of divide, then i set circles to each frame to get the circles to follow the surface, then i project the circles to the surface to make sure they are definitely warped onto he surface. then when i want to remove the circles from the surface all my intersection tools seem to always output me still a solid surface. Do you know why?

p.s. i use grey scale images to determine circle radius's, unlike your example where you literally have circles as the image.But you just taught me a new way to use image sample to remove list items. Awesome. Thanks.

Im trying to get this effect

Permalink Reply by Danny Boyes on August 11, 2011 at 10:30am

How about something like this using the Surface Split component.

Attachments:

imageSamplerDemo2.gh, 57 KB

Permalink Reply by Michael Pryor on August 11, 2011 at 10:39am

exactly, Thanks.

Permalink Reply by RWNB on February 15, 2013 at 9:19am

hi michael,

i try to do something similiar.

however, i would like to know how to get an image from geometry color?

http://www.grasshopper3d.com/forum/topics/create-image-from-geometr...

thanks

Incidentally, where is danny?

Permalink Reply by Michael Pryor on August 11, 2011 at 10:47am

I see in your definition you extrude the circle making a cylinder to puncture the surface. Is there no way to project or remap the circle on the surface and cut it? All these extrusions can sometimes make the files so slow.

Permalink Reply by Danny Boyes on August 11, 2011 at 12:11pm

The Split Surface Component uses curves as the trimming component so there should be no reason why you couldn't use projected curves.

Permalink Reply by Michael Pryor on August 11, 2011 at 12:42pm

Thanks

Permalink Reply by Michael Pryor on August 11, 2011 at 4:47pm

once you split the surface how do you remove the unwanted pieces?

Permalink Reply by Danny Boyes on August 11, 2011 at 4:50pm

If you look in the image above you can see the Cull Pattern is generated on the Area of the surfaces. so only areas above a certain size are left. You could also do it with the sort component and reverse the list to select the largest first.

Permalink Reply by Michael Pryor on August 11, 2011 at 5:10pm

hey thanks alot, I dunno how you guys remember all this stuff, regardless now I can help another.

Permalink Reply by Michael Pryor on December 17, 2011 at 4:14pm

http://www.suckerpunchdaily.com/2011/06/20/rossiyas-flourish/#more-...