---
_id: '60189'
abstract:
- lang: eng
  text: <jats:title>Abstract</jats:title><jats:p>Several state‐of‐the‐art algorithms
    for semi‐structured hexahedral meshing involve a so called <jats:italic>quantization</jats:italic>
    step to decide on the integer DoFs of the meshing problem, corresponding to the
    number of hexahedral elements to embed into certain regions of the domain. Existing
    reliable methods for quantization are based on solving a sequence of <jats:italic>integer
    quadratic programs</jats:italic> (IQP). Solving these in a timely and predictable
    manner with general‐purpose solvers is a challenge, even more so in the open‐source
    field. We present here an alternative robust and efficient quantization scheme
    that is instead based on solving a series of continuous <jats:italic>linear programs</jats:italic>
    (LP), for which solver availability and efficiency are not an issue. In our formulation,
    such LPs are used to determine where inflation or deflation of virtual hexahedral
    sheets are favorable. We compare our method to two implementations of the former
    IQP formulation (using a commercial and an open‐source MIP solver, respectively),
    finding that (a) the solutions found by our method are near‐optimal or optimal
    in most cases, (b) these solutions are found within a much more predictable time
    frame, and (c) the state of the art run time is outperformed, in the case of using
    the open‐source solver by orders of magnitude.</jats:p>
author:
- first_name: Hendrik
  full_name: Brückler, Hendrik
  id: '115694'
  last_name: Brückler
- first_name: David
  full_name: Bommes, David
  last_name: Bommes
- first_name: Marcel
  full_name: Campen, Marcel
  id: '114904'
  last_name: Campen
  orcid: 0000-0003-2340-3462
citation:
  ama: Brückler H, Bommes D, Campen M. Integer‐Sheet‐Pump Quantization for Hexahedral
    Meshing. <i>Comput Graph Forum</i>. 2024;43(5). doi:<a href="https://doi.org/10.1111/cgf.15131">10.1111/cgf.15131</a>
  apa: Brückler, H., Bommes, D., &#38; Campen, M. (2024). Integer‐Sheet‐Pump Quantization
    for Hexahedral Meshing. <i>Comput. Graph. Forum</i>, <i>43</i>(5). <a href="https://doi.org/10.1111/cgf.15131">https://doi.org/10.1111/cgf.15131</a>
  bibtex: '@article{Brückler_Bommes_Campen_2024, title={Integer‐Sheet‐Pump Quantization
    for Hexahedral Meshing}, volume={43}, DOI={<a href="https://doi.org/10.1111/cgf.15131">10.1111/cgf.15131</a>},
    number={5}, journal={Comput. Graph. Forum}, publisher={Wiley}, author={Brückler,
    Hendrik and Bommes, David and Campen, Marcel}, year={2024} }'
  chicago: Brückler, Hendrik, David Bommes, and Marcel Campen. “Integer‐Sheet‐Pump
    Quantization for Hexahedral Meshing.” <i>Comput. Graph. Forum</i> 43, no. 5 (2024).
    <a href="https://doi.org/10.1111/cgf.15131">https://doi.org/10.1111/cgf.15131</a>.
  ieee: 'H. Brückler, D. Bommes, and M. Campen, “Integer‐Sheet‐Pump Quantization for
    Hexahedral Meshing,” <i>Comput. Graph. Forum</i>, vol. 43, no. 5, 2024, doi: <a
    href="https://doi.org/10.1111/cgf.15131">10.1111/cgf.15131</a>.'
  mla: Brückler, Hendrik, et al. “Integer‐Sheet‐Pump Quantization for Hexahedral Meshing.”
    <i>Comput. Graph. Forum</i>, vol. 43, no. 5, Wiley, 2024, doi:<a href="https://doi.org/10.1111/cgf.15131">10.1111/cgf.15131</a>.
  short: H. Brückler, D. Bommes, M. Campen, Comput. Graph. Forum 43 (2024).
date_created: 2025-06-11T13:47:29Z
date_updated: 2025-06-23T09:01:46Z
department:
- _id: '969'
doi: 10.1111/cgf.15131
extern: '1'
intvolume: '        43'
issue: '5'
language:
- iso: eng
publication: Comput. Graph. Forum
publication_identifier:
  issn:
  - 0167-7055
  - 1467-8659
publication_status: published
publisher: Wiley
status: public
title: Integer‐Sheet‐Pump Quantization for Hexahedral Meshing
type: journal_article
user_id: '114904'
volume: 43
year: '2024'
...
---
_id: '60314'
abstract:
- lang: eng
  text: <jats:p>A method for the construction of bijective volumetric maps between
    3D shapes is presented. Arbitrary shapes of ball-topology are supported, overcoming
    restrictions of previous methods to convex or star-shaped targets. In essence,
    the mapping problem is decomposed into a set of simpler mapping problems, each
    of which can be solved with previous methods for discrete star-shaped mapping
    problems. Addressing the key challenges in this endeavor, algorithms are described
    to reliably construct structurally compatible partitions of two shapes with constraints
    regarding star-shapedness and to compute a parsimonious common refinement of two
    triangulations.</jats:p>
author:
- first_name: Steffen
  full_name: Hinderink, Steffen
  id: '116615'
  last_name: Hinderink
- first_name: Hendrik
  full_name: Brückler, Hendrik
  id: '115694'
  last_name: Brückler
- first_name: Marcel
  full_name: Campen, Marcel
  id: '114904'
  last_name: Campen
  orcid: 0000-0003-2340-3462
citation:
  ama: Hinderink S, Brückler H, Campen M. Bijective Volumetric Mapping via Star Decomposition.
    <i>ACM Transactions on Graphics</i>. 2024;43(6):1-11. doi:<a href="https://doi.org/10.1145/3687950">10.1145/3687950</a>
  apa: Hinderink, S., Brückler, H., &#38; Campen, M. (2024). Bijective Volumetric
    Mapping via Star Decomposition. <i>ACM Transactions on Graphics</i>, <i>43</i>(6),
    1–11. <a href="https://doi.org/10.1145/3687950">https://doi.org/10.1145/3687950</a>
  bibtex: '@article{Hinderink_Brückler_Campen_2024, title={Bijective Volumetric Mapping
    via Star Decomposition}, volume={43}, DOI={<a href="https://doi.org/10.1145/3687950">10.1145/3687950</a>},
    number={6}, journal={ACM Transactions on Graphics}, publisher={Association for
    Computing Machinery (ACM)}, author={Hinderink, Steffen and Brückler, Hendrik and
    Campen, Marcel}, year={2024}, pages={1–11} }'
  chicago: 'Hinderink, Steffen, Hendrik Brückler, and Marcel Campen. “Bijective Volumetric
    Mapping via Star Decomposition.” <i>ACM Transactions on Graphics</i> 43, no. 6
    (2024): 1–11. <a href="https://doi.org/10.1145/3687950">https://doi.org/10.1145/3687950</a>.'
  ieee: 'S. Hinderink, H. Brückler, and M. Campen, “Bijective Volumetric Mapping via
    Star Decomposition,” <i>ACM Transactions on Graphics</i>, vol. 43, no. 6, pp.
    1–11, 2024, doi: <a href="https://doi.org/10.1145/3687950">10.1145/3687950</a>.'
  mla: Hinderink, Steffen, et al. “Bijective Volumetric Mapping via Star Decomposition.”
    <i>ACM Transactions on Graphics</i>, vol. 43, no. 6, Association for Computing
    Machinery (ACM), 2024, pp. 1–11, doi:<a href="https://doi.org/10.1145/3687950">10.1145/3687950</a>.
  short: S. Hinderink, H. Brückler, M. Campen, ACM Transactions on Graphics 43 (2024)
    1–11.
date_created: 2025-06-23T09:09:51Z
date_updated: 2025-07-14T12:33:54Z
department:
- _id: '969'
doi: 10.1145/3687950
extern: '1'
intvolume: '        43'
issue: '6'
language:
- iso: eng
page: 1-11
publication: ACM Transactions on Graphics
publication_identifier:
  issn:
  - 0730-0301
  - 1557-7368
publication_status: published
publisher: Association for Computing Machinery (ACM)
status: public
title: Bijective Volumetric Mapping via Star Decomposition
type: journal_article
user_id: '117512'
volume: 43
year: '2024'
...
---
_id: '60354'
abstract:
- lang: eng
  text: <jats:p>We present a set of operators to perform modifications, in particular
    collapses and splits, in volumetric cell complexes which are discretely embedded
    in a background mesh. Topological integrity and geometric embedding validity are
    carefully maintained. We apply these operators strategically to volumetric block
    decompositions, so-called T-meshes or base complexes, in the context of hexahedral
    mesh generation. This allows circumventing the expensive and unreliable global
    volumetric remapping step in the versatile meshing pipeline based on 3D integer-grid
    maps. In essence, we reduce this step to simpler local cube mapping problems,
    for which reliable solutions are available. As a consequence, the robustness of
    the mesh generation process is increased, especially when targeting coarse or
    block-structured hexahedral meshes. We furthermore extend this pipeline to support
    feature alignment constraints, and systematically respect these throughout, enabling
    the generation of meshes that align to points, curves, and surfaces of special
    interest, whether on the boundary or in the interior of the domain.</jats:p>
author:
- first_name: Hendrik
  full_name: Brückler, Hendrik
  id: '115694'
  last_name: Brückler
- first_name: Marcel
  full_name: Campen, Marcel
  id: '114904'
  last_name: Campen
  orcid: 0000-0003-2340-3462
citation:
  ama: Brückler H, Campen M. Collapsing Embedded Cell Complexes for Safer Hexahedral
    Meshing. <i>ACM Transactions on Graphics</i>. 2023;42(6):1-24. doi:<a href="https://doi.org/10.1145/3618384">10.1145/3618384</a>
  apa: Brückler, H., &#38; Campen, M. (2023). Collapsing Embedded Cell Complexes for
    Safer Hexahedral Meshing. <i>ACM Transactions on Graphics</i>, <i>42</i>(6), 1–24.
    <a href="https://doi.org/10.1145/3618384">https://doi.org/10.1145/3618384</a>
  bibtex: '@article{Brückler_Campen_2023, title={Collapsing Embedded Cell Complexes
    for Safer Hexahedral Meshing}, volume={42}, DOI={<a href="https://doi.org/10.1145/3618384">10.1145/3618384</a>},
    number={6}, journal={ACM Transactions on Graphics}, publisher={Association for
    Computing Machinery (ACM)}, author={Brückler, Hendrik and Campen, Marcel}, year={2023},
    pages={1–24} }'
  chicago: 'Brückler, Hendrik, and Marcel Campen. “Collapsing Embedded Cell Complexes
    for Safer Hexahedral Meshing.” <i>ACM Transactions on Graphics</i> 42, no. 6 (2023):
    1–24. <a href="https://doi.org/10.1145/3618384">https://doi.org/10.1145/3618384</a>.'
  ieee: 'H. Brückler and M. Campen, “Collapsing Embedded Cell Complexes for Safer
    Hexahedral Meshing,” <i>ACM Transactions on Graphics</i>, vol. 42, no. 6, pp.
    1–24, 2023, doi: <a href="https://doi.org/10.1145/3618384">10.1145/3618384</a>.'
  mla: Brückler, Hendrik, and Marcel Campen. “Collapsing Embedded Cell Complexes for
    Safer Hexahedral Meshing.” <i>ACM Transactions on Graphics</i>, vol. 42, no. 6,
    Association for Computing Machinery (ACM), 2023, pp. 1–24, doi:<a href="https://doi.org/10.1145/3618384">10.1145/3618384</a>.
  short: H. Brückler, M. Campen, ACM Transactions on Graphics 42 (2023) 1–24.
date_created: 2025-06-24T07:45:44Z
date_updated: 2025-07-14T12:47:30Z
department:
- _id: '969'
doi: 10.1145/3618384
extern: '1'
intvolume: '        42'
issue: '6'
language:
- iso: eng
page: 1-24
publication: ACM Transactions on Graphics
publication_identifier:
  issn:
  - 0730-0301
  - 1557-7368
publication_status: published
publisher: Association for Computing Machinery (ACM)
status: public
title: Collapsing Embedded Cell Complexes for Safer Hexahedral Meshing
type: journal_article
user_id: '117512'
volume: 42
year: '2023'
...
---
_id: '60366'
abstract:
- lang: eng
  text: <jats:title>Abstract</jats:title><jats:p>The so‐called motorcycle graph has
    been employed in recent years for various purposes in the context of structured
    and aligned block decomposition of 2D shapes and 2‐manifold surfaces. Applications
    are in the fields of surface parametrization, spline space construction, semi‐structured
    quad mesh generation, or geometry data compression. We describe a generalization
    of this motorcycle graph concept to the three‐dimensional volumetric setting.
    Through careful extensions aware of topological intricacies of this higher‐dimensional
    setting, we are able to guarantee important block decomposition properties also
    in this case. We describe algorithms for the construction of this 3D motorcycle
    complex on the basis of either hexahedral meshes or seamless volumetric parametrizations.
    Its utility is illustrated on examples in hexahedral mesh generation and volumetric
    T‐spline construction.</jats:p>
author:
- first_name: Hendrik
  full_name: Brückler, Hendrik
  id: '115694'
  last_name: Brückler
- first_name: Ojaswi
  full_name: Gupta, Ojaswi
  last_name: Gupta
- first_name: Manish
  full_name: Mandad, Manish
  last_name: Mandad
- first_name: Marcel
  full_name: Campen, Marcel
  id: '114904'
  last_name: Campen
  orcid: 0000-0003-2340-3462
citation:
  ama: Brückler H, Gupta O, Mandad M, Campen M. The 3D Motorcycle Complex for Structured
    Volume Decomposition. <i>Computer Graphics Forum</i>. 2022;41(2):221-235. doi:<a
    href="https://doi.org/10.1111/cgf.14470">10.1111/cgf.14470</a>
  apa: Brückler, H., Gupta, O., Mandad, M., &#38; Campen, M. (2022). The 3D Motorcycle
    Complex for Structured Volume Decomposition. <i>Computer Graphics Forum</i>, <i>41</i>(2),
    221–235. <a href="https://doi.org/10.1111/cgf.14470">https://doi.org/10.1111/cgf.14470</a>
  bibtex: '@article{Brückler_Gupta_Mandad_Campen_2022, title={The 3D Motorcycle Complex
    for Structured Volume Decomposition}, volume={41}, DOI={<a href="https://doi.org/10.1111/cgf.14470">10.1111/cgf.14470</a>},
    number={2}, journal={Computer Graphics Forum}, publisher={Wiley}, author={Brückler,
    Hendrik and Gupta, Ojaswi and Mandad, Manish and Campen, Marcel}, year={2022},
    pages={221–235} }'
  chicago: 'Brückler, Hendrik, Ojaswi Gupta, Manish Mandad, and Marcel Campen. “The
    3D Motorcycle Complex for Structured Volume Decomposition.” <i>Computer Graphics
    Forum</i> 41, no. 2 (2022): 221–35. <a href="https://doi.org/10.1111/cgf.14470">https://doi.org/10.1111/cgf.14470</a>.'
  ieee: 'H. Brückler, O. Gupta, M. Mandad, and M. Campen, “The 3D Motorcycle Complex
    for Structured Volume Decomposition,” <i>Computer Graphics Forum</i>, vol. 41,
    no. 2, pp. 221–235, 2022, doi: <a href="https://doi.org/10.1111/cgf.14470">10.1111/cgf.14470</a>.'
  mla: Brückler, Hendrik, et al. “The 3D Motorcycle Complex for Structured Volume
    Decomposition.” <i>Computer Graphics Forum</i>, vol. 41, no. 2, Wiley, 2022, pp.
    221–35, doi:<a href="https://doi.org/10.1111/cgf.14470">10.1111/cgf.14470</a>.
  short: H. Brückler, O. Gupta, M. Mandad, M. Campen, Computer Graphics Forum 41 (2022)
    221–235.
date_created: 2025-06-25T08:52:53Z
date_updated: 2025-07-14T12:47:02Z
department:
- _id: '969'
doi: 10.1111/cgf.14470
extern: '1'
intvolume: '        41'
issue: '2'
language:
- iso: eng
page: 221-235
publication: Computer Graphics Forum
publication_identifier:
  issn:
  - 0167-7055
  - 1467-8659
publication_status: published
publisher: Wiley
status: public
title: The 3D Motorcycle Complex for Structured Volume Decomposition
type: journal_article
user_id: '117512'
volume: 41
year: '2022'
...
---
_id: '60372'
abstract:
- lang: eng
  text: <jats:p>Developments in the field of parametrization-based quad mesh generation
    on surfaces have been impactful over the past decade. In this context, an important
    advance has been the replacement of error-prone rounding in the generation of
    integer-grid maps, by robust quantization methods. In parallel, parametrization-based
    hex mesh generation for volumes has been advanced. In this volumetric context,
    however, the state-of-the-art still relies on fragile rounding, not rarely producing
    defective meshes, especially when targeting a coarse mesh resolution. We present
    a method to robustly quantize volume parametrizations, i.e., to determine guaranteed
    valid choices of integers for 3D integer-grid maps. Inspired by the 2D case, we
    base our construction on a non-conforming cell decomposition of the volume, a
    3D analogue of a T-mesh. In particular, we leverage the motorcycle complex, a
    recent generalization of the motorcycle graph, for this purpose. Integer values
    are expressed in a differential manner on the edges of this complex, enabling
    the efficient formulation of the conditions required to strictly prevent forcing
    the map into degeneration. Applying our method in the context of hexahedral meshing,
    we demonstrate that hexahedral meshes can be generated with significantly improved
    flexibility.</jats:p>
author:
- first_name: Hendrik
  full_name: Brückler, Hendrik
  id: '115694'
  last_name: Brückler
- first_name: David
  full_name: Bommes, David
  last_name: Bommes
- first_name: Marcel
  full_name: Campen, Marcel
  id: '114904'
  last_name: Campen
  orcid: 0000-0003-2340-3462
citation:
  ama: Brückler H, Bommes D, Campen M. Volume parametrization quantization for hexahedral
    meshing. <i>ACM Transactions on Graphics</i>. 2022;41(4):1-19. doi:<a href="https://doi.org/10.1145/3528223.3530123">10.1145/3528223.3530123</a>
  apa: Brückler, H., Bommes, D., &#38; Campen, M. (2022). Volume parametrization quantization
    for hexahedral meshing. <i>ACM Transactions on Graphics</i>, <i>41</i>(4), 1–19.
    <a href="https://doi.org/10.1145/3528223.3530123">https://doi.org/10.1145/3528223.3530123</a>
  bibtex: '@article{Brückler_Bommes_Campen_2022, title={Volume parametrization quantization
    for hexahedral meshing}, volume={41}, DOI={<a href="https://doi.org/10.1145/3528223.3530123">10.1145/3528223.3530123</a>},
    number={4}, journal={ACM Transactions on Graphics}, publisher={Association for
    Computing Machinery (ACM)}, author={Brückler, Hendrik and Bommes, David and Campen,
    Marcel}, year={2022}, pages={1–19} }'
  chicago: 'Brückler, Hendrik, David Bommes, and Marcel Campen. “Volume Parametrization
    Quantization for Hexahedral Meshing.” <i>ACM Transactions on Graphics</i> 41,
    no. 4 (2022): 1–19. <a href="https://doi.org/10.1145/3528223.3530123">https://doi.org/10.1145/3528223.3530123</a>.'
  ieee: 'H. Brückler, D. Bommes, and M. Campen, “Volume parametrization quantization
    for hexahedral meshing,” <i>ACM Transactions on Graphics</i>, vol. 41, no. 4,
    pp. 1–19, 2022, doi: <a href="https://doi.org/10.1145/3528223.3530123">10.1145/3528223.3530123</a>.'
  mla: Brückler, Hendrik, et al. “Volume Parametrization Quantization for Hexahedral
    Meshing.” <i>ACM Transactions on Graphics</i>, vol. 41, no. 4, Association for
    Computing Machinery (ACM), 2022, pp. 1–19, doi:<a href="https://doi.org/10.1145/3528223.3530123">10.1145/3528223.3530123</a>.
  short: H. Brückler, D. Bommes, M. Campen, ACM Transactions on Graphics 41 (2022)
    1–19.
date_created: 2025-06-25T09:07:20Z
date_updated: 2025-07-14T12:47:23Z
department:
- _id: '969'
doi: 10.1145/3528223.3530123
extern: '1'
intvolume: '        41'
issue: '4'
language:
- iso: eng
page: 1-19
publication: ACM Transactions on Graphics
publication_identifier:
  issn:
  - 0730-0301
  - 1557-7368
publication_status: published
publisher: Association for Computing Machinery (ACM)
status: public
title: Volume parametrization quantization for hexahedral meshing
type: journal_article
user_id: '117512'
volume: 41
year: '2022'
...
