Morphing accuracy

[OmarBahig (Omar)]

Good day @pgalibarov @dschander

I have a question regarding morphing accuracy. I know that we can measure the distance between the target landmarks and the morphed source bones but I do not how to find the morphed landmarks of the source. I know that we will get an error for each corresponding landmarks.

I have made the morphing algorithm for the patella bone. Please find the script (with the chosen landmarks) and the stl files i used. Is it possible to extract the morphed points in such a script? and how?

I have noticed that in RBF function there is Points0Pretranformed underneath Points0 while Points1 does not have that. Does this mean that Points0PreTransformed is the morphed source points?

Patella.main.any (4.0 KB)
Patella_source and target bones.zip (1.8 MB)

Thank you in advance.

Best regards,
Omar

[dschander (Divyaksh S. Chander)]

Hi Omar,

When you use RBF transformation, the source and target landmarks will coincide after the transformation. You will not see any error in the corresponding landmarks. I am not sure why you think that you will see errors in the corresponding landmarks. Please correct me, if I misunderstood you

I think your code is almost there. You are drawing the point clouds between unmorphed source landmarks and target landmarks. If you want to view the morphed landmarks, please pass the points through the RBF function. Add the following lines inside the scope of glfr in your script:

    AnyDrawPointCloud drwSrc_Morphed = {
      Points = Main.MyModel.RBF(..RBF.Points0);
      Opacity = 0.5;
      PointStyle = {
        Style = PointStyleSphere;// Marker style.
        Size = 0.004;// Size of markers.
      };
      Points3D = On;
      RGB={1,0,0};
      
    };
    AnyFloat CheckError = drwSrc_Morphed.Points-drwTrg.Points;

The last line checks the error between the morphed source landmarks and the target landmarks and you can verify that it is 0.

Regarding Points0Pretransformed, as the description says, these are points0 (source landmarks) after the pretransform is applied to them. In your script you have used the Affine transform as a pretransform, so Point0Pretransformed are Points0 after applying the Affine transform. Again, you are welcome to add the drawing of these points in your script:

    AnyDrawPointCloud drwSrc_PreTransformed = {
      Points = ..RBF.Points0Pretransformed;
      Opacity = 0.5;
      PointStyle = {
        Style = PointStyleSphere;// Marker style.
        Size = 0.004;// Size of markers.
      };
      Points3D = On;
      RGB={0,1,0};
      
    };
    AnyDrawPointCloud drwSrc_affine = {
      Points = Main.MyModel.Affine(..Affine.Points0);
      Opacity = 1;
      PointStyle = {
        Style = PointStyleSphere;// Marker style.
        Size = 0.002;// Size of markers.
      };
      Points3D = On;
      RGB={1,0,0};
      
    };

I hope that helps.

Best regards,
Dave