TY - GEN A1 - Knötel, David A1 - Becker, Carola A1 - Scholtz, Gerhard A1 - Baum, Daniel T1 - Global and Local Mesh Morphing for Complex Biological Objects from microCT Data N2 - We show how biologically coherent mesh models of animals can be created from μCT data to generate artificial yet naturally looking intermediate objects. The whole pipeline of processing algorithms is presented, starting from generating topologically equivalent surface meshes, followed by solving the correspondence problem, and, finally, creating a surface morphing. In this pipeline, we address all the challenges that are due to dealing with complex biological, non-isometric objects. For biological objects it is often particularly important to obtain deformations that look as realistic as possible. In addition, spatially non-uniform shape morphings that only change one part of the surface and keep the rest as stable as possible are of interest for evolutionary studies, since functional modules often change independently from one another. We use Poisson interpolation for this purpose and show that it is well suited to generate both global and local shape deformations. T3 - ZIB-Report - 18-53 KW - Mesh interpolation KW - Geometry processing KW - microCT Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-70618 SN - 1438-0064 ER - TY - CHAP A1 - Knötel, David A1 - Becker, Carola A1 - Scholtz, Gerhard A1 - Baum, Daniel T1 - Global and Local Mesh Morphing for Complex Biological Objects from microCT Data T2 - Eurographics Workshop on Visual Computing for Biology and Medicine (VCBM) N2 - We show how biologically coherent mesh models of animals can be created from μCT data to generate artificial yet naturally looking intermediate objects. The whole pipeline of processing algorithms is presented, starting from generating topologically equivalent surface meshes, followed by solving the correspondence problem, and, finally, creating a surface morphing. In this pipeline, we address all the challenges that are due to dealing with complex biological, non-isometric objects. For biological objects it is often particularly important to obtain deformations that look as realistic as possible. In addition, spatially non-uniform shape morphings that only change one part of the surface and keep the rest as stable as possible are of interest for evolutionary studies, since functional modules often change independently from one another. We use Poisson interpolation for this purpose and show that it is well suited to generate both global and local shape deformations. Y1 - 2018 U6 - https://doi.org/10.2312/vcbm.20181243 SP - 179 EP - 183 CY - Granada, Spain ER - TY - JOUR A1 - Scholtz, Gerhard A1 - Knötel, David A1 - Baum, Daniel T1 - D’Arcy W. Thompson’s Cartesian transformations: a critical evaluation JF - Zoomorphology N2 - The images of D’Arcy Wentworth Thompson’s book “On Growth and Form” got an iconic status and became influential for biometrics and other mathematical approaches to organismic form. In particular, this is true for those of the chapter on the theory of transformation, which even has an impact on art and humanities. Based on his approach, Thompson formulated far-reaching conclusions with a partly anti-Darwinian stance. Here, we use the example of Thompson’s transformation of crab carapaces to test to what degree the transformation of grids, landmarks, and shapes result in congruent images. For comparison, we applied the same series of tests to digitized carapaces of real crabs. Both approaches show similar results. Only the simple transformations show a reasonable form of congruence. In particular, the transformations to majoid spider crabs reveal a complicated transformation of grids with partly crossing lines. By contrast, the carapace of the lithodid species is relatively easily created despite the fact that it is no brachyuran, but evolved a spider crab-like shape convergently from a hermit crab ancestor. Y1 - 2020 U6 - https://doi.org/10.1007/s00435-020-00494-1 VL - 139 SP - 293 EP - 308 ER -