# Loft from 2 surfaces

Hi i’m trying to make a loft between 2 surfaces, extracting the edges from the surfaces and making a regular straight loft.
The problem is that the loft result isn’t correct for what im trying to do.
What’s the problem in my test?
Have i miss something?

I’ve tried to reorder the edge list of one of the two surfaces because i think that the loft result is connected to the edges order.
But the problem still remain.

Image Sampler_4 (irrisolto).gh (165.4 KB)

The image that i used to move surface points is below

Flatten the ‘C’ input to Loft and use ‘Loft options | Align sections’:

Adding bottom and top surfaces to get “Closed Brep”:

It works thank you.
But i have a question the Align Section operation, why use that?
It’s because the edges of the two surfaces weren’t aligned or ordered one by one?

The curves used by Loft must all have the same direction. Closed curves must have their seams (start/end points) aligned. Otherwise, the loft results are a twisted mess.

By the way, it looked like the aspect ratio of your surface isn’t the same as the image?
Surface: 37 / 57 = 0.649, Image: 564 / 725 = 0.778

Understood. Thanks a lot
For the image: i’m starting now to use grasshopper so i was just trying to test the Image Sampler Component.
If i need to how can i change the aspect ratio?
Using Photoshop?
Thanks

Change the surface dimensions to match the photo!

564 / 725 X 57 = 44.34 so a surface 44.34 X 57 will match the photo’s aspect ratio. This avoids distortion of the image.

Image_Sampler_4 (irrisolto)_2019Oct29a.gh (173.5 KB)

Note that at higher resolutions, a flaw in the image can be detected. There are white bars at top and bottom that resolve to a slightly higher elevation than the slightly gray background for the main image. That can easily be fixed in GIMP or Photoshop by removing the light gray background that leaves two white bars barely visible.

Maximum on the ‘Resolution’ sider is 725, the longer image dimension in pixels.

Simplified: (below)

Image_Sampler_4 (irrisolto)_2019Oct29b.gh (172.4 KB)

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