3D signed distance transform

6 次查看(过去 30 天)
Hi, I need to do some signed 3D Euclidean distance transform, and need the distance to be negative inside a closed surface. The 3D Euclidean Distance Transform for Variable Data Aspect Ratio in file exchange works well, but it only provides positive distance for all points that are not on the closed surface. Now I need to detect if a given point is inside the closed surface or not. Any hint to tell if a point is inside the closed surface? Or to signed 3D distance transform? Any help will be immensely appreciated. Erhong
  1 个评论
Ziwei Wu
Ziwei Wu 2016-11-28
Hi Erhong, I am trying to make a 3D shape model using signed distance function but there are always some problems with my code. Would it be possible for you to share your code to me? Or just give me some hint of your idea? Thank you so much!

请先登录,再进行评论。

采纳的回答

Sean de Wolski
Sean de Wolski 2011-4-13
You could separately create a map of points inside a closed surface.
M = imfill(bw_image,'holes');
Now anything true in M will be inside a closed surface in bw_image.
D = your_distance_transform;
D(M) = -D(M);
  3 个评论
Sean de Wolski
Sean de Wolski 2011-4-14
M should be a logical 3-dimensional array.
Please tell me what the output from these commands is:
class(M)
size(M)
Thus D (your distance transform matrix) should be of class double and the same size as M.
Then the indexing assignment D(M) = -D(M) will work.
Erhong
Erhong 2011-4-14
Thanks so much for the hint. I replaced the M in D(M) with the corresponding cocordinates, and it works!
Thank you!

请先登录,再进行评论。

更多回答(0 个)

类别

Help CenterFile Exchange 中查找有关 Computational Geometry 的更多信息

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by