https://community.esri.com/t5/3d-cities-campuses-questions/workflow-for-extracting-combined-3d-terrain/m-p/1652059#M126 <P>Hello everyone,</P><P>I am working on a project where I need to prepare <STRONG>combined 3D geometries of an urban area (terrain + buildings)</STRONG> in <STRONG>ArcGIS Pro</STRONG> for <STRONG>Computational Fluid Dynamics (CFD) wind field simulations</STRONG>.</P><P>My goals are:</P><UL><LI><P>Generate a <STRONG>3D terrain surface</STRONG> (from DEM or similar data).</P></LI><LI><P>Integrate <STRONG>3D buildings</STRONG> (from building footprints + height attributes) on top of the terrain.</P></LI><LI><P>Export the final geometry as a <STRONG>single integrated 3D dataset</STRONG> (multipatch or CAD format like STL/STEP/OBJ) for direct use in CFD software.</P></LI></UL><P>Where I need guidance:</P><OL><LI><P>What is the best workflow in ArcGIS Pro to merge <STRONG>DEM-based terrain</STRONG> and <STRONG>building geometries</STRONG> into one combined 3D model?</P></LI><LI><P>For buildings without height data, what are the recommended approaches or data sources (for U.S. cities such as Birmingham, AL)?</P></LI><LI><P>Which export format works best when transferring the unified 3D model from ArcGIS Pro into CFD tools?</P></LI></OL><P>If anyone has experience with <STRONG>integrating terrain and buildings into a single geometry</STRONG> in ArcGIS Pro (or possibly CityEngine), I would appreciate detailed workflow steps, recommended tools, or tips on avoiding issues with flat surfaces / misalignment.</P><P>Thanks in advance for your help!</P> Mon, 22 Sep 2025 09:39:23 GMT HarnishkumarPatel 2025-09-22T09:39:23Z https://community.esri.com/t5/3d-cities-campuses-questions/workflow-for-extracting-combined-3d-terrain/m-p/1652059#M126 <P>Hello everyone,</P><P>I am working on a project where I need to prepare <STRONG>combined 3D geometries of an urban area (terrain + buildings)</STRONG> in <STRONG>ArcGIS Pro</STRONG> for <STRONG>Computational Fluid Dynamics (CFD) wind field simulations</STRONG>.</P><P>My goals are:</P><UL><LI><P>Generate a <STRONG>3D terrain surface</STRONG> (from DEM or similar data).</P></LI><LI><P>Integrate <STRONG>3D buildings</STRONG> (from building footprints + height attributes) on top of the terrain.</P></LI><LI><P>Export the final geometry as a <STRONG>single integrated 3D dataset</STRONG> (multipatch or CAD format like STL/STEP/OBJ) for direct use in CFD software.</P></LI></UL><P>Where I need guidance:</P><OL><LI><P>What is the best workflow in ArcGIS Pro to merge <STRONG>DEM-based terrain</STRONG> and <STRONG>building geometries</STRONG> into one combined 3D model?</P></LI><LI><P>For buildings without height data, what are the recommended approaches or data sources (for U.S. cities such as Birmingham, AL)?</P></LI><LI><P>Which export format works best when transferring the unified 3D model from ArcGIS Pro into CFD tools?</P></LI></OL><P>If anyone has experience with <STRONG>integrating terrain and buildings into a single geometry</STRONG> in ArcGIS Pro (or possibly CityEngine), I would appreciate detailed workflow steps, recommended tools, or tips on avoiding issues with flat surfaces / misalignment.</P><P>Thanks in advance for your help!</P> Mon, 22 Sep 2025 09:39:23 GMT https://community.esri.com/t5/3d-cities-campuses-questions/workflow-for-extracting-combined-3d-terrain/m-p/1652059#M126 HarnishkumarPatel 2025-09-22T09:39:23Z