Automated Crosshatching

Comment

Comment by Andrew Heumann on July 1, 2011 at 1:08am

definition available here

Comment by Eric Laine on June 29, 2011 at 12:50am

would you mind posting the Grasshopper definition?  As far as I can tell I've duplicated everything exactly.  I can tell the centroids have different values based on the image sampling, but the hatchCurves component never produces a hatch.  The "out" and "a" are always empty.  I'm sure I'm missing something really minor.

Awesome effect though, really cool!  Thanks

 

Eric

Comment by Andrew Heumann on June 21, 2011 at 10:47pm

not sure what you mean by subdivisions. The darkness of the area defines the scale of the hatch - a darker area gets a smaller (and therefore denser) hatch. 

 

Definition looks like this: first you need the exported curves from illustrator and a PictureFrame in rhino with the right image aligned to the curves.

 

The HatchCurves script can be downloaded from http://parametricmodel.com/HatchCurves/43.html

Comment by John Fredrickson on June 21, 2011 at 9:57pm

So how does the hatch work? The darkness of the area determines the number of subdivisons? Can you post your ghx or a screenshot?

Comment by Andrew Heumann on June 21, 2011 at 7:06pm

basically illustrator live trace produces a set of closed regions, which I export to rhino. in rhino I load the curves and the original image into grasshopper, and evaluate the brightness of the image at the center of each region. Then I use a script I wrote to automate baking hatches, and set the hatch scale to correspond to the brightness value.

Comment by Wiktor Kidziak on June 21, 2011 at 5:18am

can you explain a bit about the process of 'image-density weighted hatches' please ?