The are essentially two approaches to free quad meshing:

• Direct methods generate a quad mesh directly, usually by some advancing front method. The Paving paper is a standard reference and is the method used by CUBIT, so you have seen these meshes in many publications.

• Indirect methods generate some intermediate decomposition of the domain (e.g. triangles) and then produce an all-quad mesh through recombination and/or further decomposition. Q-Morph is an example that is used by ANSYS.

Note that smoothing is necessary for both approaches, sometimes with alternating topology fix-up and smoothing steps. Some open source tools have built-in smoothing facilities and the LGPL-licensed Mesquite package is designed as a library specifically for mesh quality improvement.

I know of two open source free-quad meshers:

• Gmsh (GPL with linking exception) can generate quad meshes using a recombination algorithm described in this paper.
• The Jaal component of MeshKit (LGPL) is based on recombination similar to Q-Morph above, read the IMR-2011 paper for more details. You can download the source through the link above, but it is not ready for production use yet.
• LBIE generates quad and hex meshes from volumetric data. From what I can tell, it is an interactive environment rather than a library. The site says that the source is available under GPL upon request.
• CUBIT is not open source (and although not expensive compared to commercial software, acquiring a license takes a long time), but produces high quality meshes and can be linked into other applications.

The are essentially two approaches to free quad meshing:

• Direct methods generate a quad mesh directly, usually by some advancing front method. The Paving paper is a standard reference and is the method used by CUBIT, so you have seen these meshes in many publications.

• Indirect methods generate some intermediate decomposition of the domain (e.g. triangles) and then produce an all-quad mesh through recombination and/or further decomposition. Q-Morph is an example that is used by ANSYS.

Note that smoothing is necessary for both approaches, sometimes with alternating topology fix-up and smoothing steps. Some open source tools have built-in smoothing facilities and the LGPL-licensed Mesquite package is designed as a library specifically for mesh quality improvement.

I know of two open source free-quad meshers:

• Gmsh (GPL with linking exception) can generate quad meshes using a recombination algorithm described in this paper.
• The Jaal component of MeshKit (LGPL) is based on recombination similar to Q-Morph above, read the IMR-2011 paper for more details. You can download the source through the link above, but it is not ready for production use yet.
• LBIE generates quad and hex meshes from volumetric data. From what I can tell, it is an interactive environment rather than a library. The site says that the source is available under GPL upon request.
• CUBIT is not open source (and although not expensive compared to commercial software, acquiring a license takes a long time), but produces high quality meshes and can be linked into other applications.

The are essentially two approaches to free quad meshing:

• Direct methods generate a quad mesh directly, usually by some advancing front method. The Paving paper is a standard reference and is the method used by CUBIT, so you have seen these meshes in many publications.

• Indirect methods generate some intermediate decomposition of the domain (e.g. triangles) and then produce an all-quad mesh through recombination and/or further decomposition. Q-Morph is an example that is used by ANSYS.

Note that smoothing is necessary for both approaches, sometimes with alternating topology fix-up and smoothing steps. Some open source tools have built-in smoothing facilities and the LGPL-licensed Mesquite package is designed as a library specifically for mesh quality improvement.

I believe that the Jaal component of MeshKit (LGPL) is currently the only open source free-quad mesher. You can download the source through the link above, but it is not ready for production use yet. Jaal is based on recombination similar to Q-Morph above, read the IMR-2011 paper for more details.

The are essentially two approaches to free quad meshing:

• Direct methods generate a quad mesh directly, usually by some advancing front method. The Paving paper is a standard reference and is the method used by CUBIT, so you have seen these meshes in many publications.

• Indirect methods generate some intermediate decomposition of the domain (e.g. triangles) and then produce an all-quad mesh through recombination and/or further decomposition. Q-Morph is an example that is used by ANSYS.

Note that smoothing is necessary for both approaches, sometimes with alternating topology fix-up and smoothing steps. Some open source tools have built-in smoothing facilities and the LGPL-licensed Mesquite package is designed as a library specifically for mesh quality improvement.

I know of two open source free-quad meshers:

• Gmsh (GPL with linking exception) can generate quad meshes using a recombination algorithm described in this paper.
• The Jaal component of MeshKit (LGPL) is based on recombination similar to Q-Morph above, read the IMR-2011 paper for more details. You can download the source through the link above, but it is not ready for production use yet.
• LBIE generates quad and hex meshes from volumetric data. From what I can tell, it is an interactive environment rather than a library. The site says that the source is available under GPL upon request.
• CUBIT is not open source (and although not expensive compared to commercial software, acquiring a license takes a long time), but produces high quality meshes and can be linked into other applications.