GeoMESH-TRIAL
Win64, EnglishGeneral Usage Instructions
GeoMESH offers a powerful suite of tools for working with terrain models inside AutoCAD®. At the heart of the software lies the GMESH command, which allows you to select terrain points (AutoCAD POINT elements) and create detailed triangulated irregular networks, referred to as terrain meshes. These meshes, along with the original points, are organized on dedicated GeoMESH layers.
The generation process relies on a sophisticated Constrained Delaunay Triangulation algorithm, respecting existing AutoCAD LINE elements as fixed constraints. Depending on the setting of the DETECTHOLE system variable, GMESH can produce a convex hull, refine the mesh to match boundary constraints, or even automatically detect and remove unwanted holes, giving users fine control over the final output.
To visualize terrain variations, the GMCONTOUR command interpolates the mesh surfaces and draws contour lines at defined height intervals. Base height and increments are determined by the system variables CBASE and CINKR. Flexibility is key: users can choose whether these contours are represented as lines, polylines, or splines, allowing for results tailored to the specific needs of each project.
Adding another dimension to the visualization, GMISOCONTOUR fills these contour regions with customizable color patterns. Controlled through the COLORSCHEME setting, these patterns can either be mapped in 3D or flattened into the XY-plane when ISO3DMODE is switched off—ideal for generating classic topographic maps or creating striking visual presentations.
For those needing detailed cross-sections, the GMSECTION command provides a streamlined workflow. By defining a simple 3D polyline as a cutting path, users can generate precise terrain profiles. These sections are automatically placed as blocks in the XY-plane of the active User Coordinate System (UCS), with insertion points and scaling easily adjusted to fit drawing requirements.
Imagery can also be seamlessly integrated thanks to the GMTEXTURE command, which projects orthorectified images onto GeoMESH surfaces. Regardless of the coordinate system, the projection is always perpendicular to the terrain, ensuring an accurate visual overlay. To optimize rendering performance, it is recommended to disable image frames using AutoCAD’s FRAME or IMAGEFRAME system variables. (Please note: this command can place significant demands on system resources.)
The newly introduced GMRAINDROP command simulates the natural flow of water across a terrain surface. After selecting a mesh and defining starting points, GeoMESH calculates the path of each raindrop, drawing them as 3D polylines and marking endpoints with POINT elements. For even smoother flow lines, users can activate spline drawing via the CWRITEMODE variable. As this feature is currently in beta, user feedback is highly appreciated to refine its functionality.
Volume calculations between two surfaces become effortless with the GMVOLUME command. After selecting the top and bottom meshes, GeoMESH calculates the enclosed volume based on the precision setting VOLPREC. If desired, the volume can even be visualized as a 3D solid body on a dedicated layer by activating VOLDRAW.
Importing external terrain data is made easy with two specialized commands: GMXYZIN reads XYZ-format text files, supporting a variety of delimiters and treating any line starting with # as a comment. However, files must be free of a Byte Order Mark (BOM). For point clouds in LAS format, GMLASIN offers support for versions 1.0 through 1.4, focusing on extracting X, Y, and Z coordinates—perfect for working with standard surveying data.
GeoMESH also provides flexible conversion tools: GMESH2POINT transforms 3DFACE elements into POINT elements, extracting terrain points from pre-existing meshes, while GM3FACE2MESH allows 3DFACE triangles to be converted directly into GeoMESH elements. These capabilities are invaluable for integrating data generated through other workflows into GeoMESH without the need for reprocessing.
With these powerful tools, GeoMESH enhances the capabilities of AutoCAD, offering intuitive workflows, professional-grade outputs, and the flexibility to meet a wide range of geospatial and civil engineering needs.
Screenshots
Commands
| Ribbon/Toolbar Icon | Command | Command Description |
|---|---|---|
|
GMABOUT |
Displays status information about GeoMESH. |
|
GMESH |
Generates a terrain mesh of triangles using Constrained Delauney Triangulation. Input: AutoCAD POINT elements (terrain points) and optionally AutoCAD LINE elements (constraints) are required. Constraints are used to define forced edges to which the terrain mesh will be constrained. |
|
GMCONTOUR |
Creates contour lines. Input: GeoMESH mesh elements are required. Using the system variable CWRITEMODE, contour lines are drawn as AutoCAD LINE, 3DPOLY, or 3DPOLY (spline) elements. With CBASE, the base altitude is set, and with CINCR, the increment of the contour lines. |
|
GMISOCONTOUR |
Creates contour lines. Input: GeoMESH mesh elements are required. Using the system variable CWRITEMODE, contour lines are drawn as AutoCAD LINE, 3DPOLY, or 3DPOLY (spline) elements. With CBASE, the base altitude is set, and with CINCR, the increment of the contour lines. |
|
GMSECTION |
Generates a terrain section for an existing terrain mesh. The terrain section is inserted as a block in the x-y plane of the current UCS. Input: GeoMESH mesh element,s, and afterward, decurved 3DPOLY elements are required. |
|
GMRAINDROP |
Simulates the rain flow (raindrop flow) on a terrain mesh. First, select the terrain mesh and afterwards the raindrops (POINT). All raindrop flows a drawn as 3D polylines (3DPOLY). If the GeoMESH system variable CWRITEMODE is set to 2, all raindrop flows are drawn as splines. Any endpoint (border reached or no further flow possible) of a raindrop flow is signed by a point (POINT). Note: This new command is beta. |
|
GMTEXTURE |
Applies an image to a terrain mesh. The image is always projected orthogonally onto the terrain mesh, regardless of the chosen coordinate system. Input: GeoMESH mesh elements, and afterward, one AutoCAD IMAGE element is required. Only one image can be applied per command operation. Set the AutoCAD system variable FRAME or IMAGEFRAME to 0 to make the image frames invisible for a natural view of the generated terrain simulation. |
|
GMBORDER |
Draws the border line of a terrain mesh in a separate GeoMESH layer. Input: GeoMESH mesh elements are required. |
|
GMSURFACE |
Calculates the area of the surface of a terrain mesh. Input: GeoMESH mesh elements are required. |
|
GMVOLUME |
Calculates the volume between two terrain meshes. Input: GeoMESH mesh elements are required, first the TOP mesh and second the BOTTOM mesh. VOLPREC specifies the accuracy of volume calculation. If VOLDRAW is set to ON, the resulting volume body is drawn on a separate GeoMESH layer. |
|
GM3DFACE2MESH |
Converts 3DFACE elements to GeoMESH mesh elements. Input: 3DFACE elements are required. |
|
GMESH2POINT |
Generates terrain points from 3DFACE elements. Input: 3DFACE elements are required. 3DFACE elements must be triangles. |
|
GMLINE2PLINE |
Converts a group of arbitrary AutoCAD LINE elements into a group of joined AutoCAD 3DPOLY elements. Input: AutoCAD LINE elements are required. The results are always drawn to the current layer. The selected objects will not be erased. |
|
GMXYZIN |
Reads terrain points from a text file. The file extension 'xyz' is obligatory. File format: x coordinate, y coordinate, z coordinate. As delimiter allowed: ':', ';', ',', or ' '. Any line beginning with '#' is treated as a comment line. |
|
GMLASIN |
Reads terrain points from an LAS file. The file extension 'las' is obligatory. Supported file format: Version 1.0, 1.1, 1.2, 1.3, and 1.4. Note: GMLASIN reads only the x, y, and z coordinates of any data record. For more information, please visit: https://www.asprs.org. |
|
GMSETVAR |
Lists or changes the values of GeoMESH system variables. ?: Lists all GeoMESH system variables in the drawing and their current settings. Enter GeoMESH system variables on the command line: GMSET+"variable name". |
|
GMSETCBASE |
GeoMESH System Variable CBASE (GMSETVAR -> CBASE): Contains the base altitude for contour lines and colored contour line patterns. Any real value is allowed. The default value is 0.0000. |
|
GMSETCINCR |
GeoMESH System Variable CINCR (GMSETVAR -> CINCR): Contains the altitude increment (contour lines) or the increment of the color gradation (contour line patterns). Any positive real value other than zero is allowed. The default value is 1.0000. |
|
GMSETCOLORSCHEME |
GeoMESH System Variable COLORSCHEME (GMSETVAR -> COLORSCHEME): Contains the color scheme for contour line patterns of the command GMISOCONTOUR. COLORSCHEME is a string of a maximum of 40 color codes. Any color code has three characters and is defined like the AutoCAD Color Index (ACI) of the AutoCAD command COLOR. Any integer value between 1 and 255 is allowed. The default value is '001002003004005006'. Input 'default' to reset COLORSCHEME. |
|
GMSETCWRITEMODE |
GeoMESH System Variable CWRITEMODE (GMSETVAR -> CWRITEMODE): If CWRITEMODE is set to 0, contour lines of the command GMCONTOUR are drawn using AutoCAD LINE elements. Set to 1, GeoMESH draws contour lines using AutoCAD 3DPOLY elements, and a value of 2 additionally causes the generation of splines. The default value is 1. |
|
GMSETDETECTHOLE |
GeoMESH System Variable DETECTHOLE (GMSETVAR -> DETECTHOLE): If DETECTHOLE is set to 0, GMESH produces a convex-hull. Set to 1, GMESH removes all outer triangles until a boundary is defined by constraints. Set to 2, GMESH removes outer triangles and automatically detects holes. The default value is 0. |
|
GMSETISO3DMODE |
GeoMESH System Variable ISO3DMODE (GMSETVAR -> ISO3DMODE): If ISO3DMODE is set to OFF, colored contour line patterns of the command GMISOCONTOUR are drawn in the x-y-plane with a constant z coordinate of CBASE. The default value is OFF. |
|
GMSETVOLDRAW |
GeoMESH System Variable VOLDRAW (GMSETVAR -> VOLDRAW): If VOLDRAW is set to ON, the volume body of the command GMVOLUME is drawn to a separate GeoMESH layer. The default value is OFF. |
|
GMSETVOLPREC |
GeoMESH System Variable VOLPREC (GMSETVAR -> VOLPREC): Contains the precision value for calculating the volume between two terrain meshes of the command GMVOLUME. Any positive integer between 10 and 1000 is allowed. The default value is 100. |
Installation/Uninstallation
The installer that was run when you downloaded this app/plugin from the Autodesk App Store will start installing the app/plugin. OR, simply double-click the downloaded installer to install the app/plugin. You may need to restart your Autodesk product to activate the app/plugin. To uninstall this plugin, exit the Autodesk product if you are currently running it, and simply rerun the installer and select the "Uninstall" button. OR click Control Panel > Programs > Programs and Features (Windows 10/11) and uninstall as you would any other system application.
Additional Information
The following are important notes for all GeoMESH commands:
- GeoMESH stores all GeoMESH system variables in the current drawing.
- GeoMESH writes generated data in its own GeoMESH layers. The following default layer names and layer colors are used for this:
- Terrain Points: Name: GM_POINT; Color: green
- Constraints: Name: GM_CONSTRAINT; Color: magenta
- Terrain Mesh: Name: GM_MESH; Color: grey (252)
- Contours: Name: GM_CONTOUR; Color: yellow
- Contour Line Patterns: Name: 'GM_ISOCONTOUR'; Color: white
- Sections: Name: GM_SECTION; Color: cyan
- Volumes: Name: GM_VOLUME; Color: blue; Status: frozen
- Textures: Name: GM_TEXTURE; Color: white
- Bordes: Name: GM_BORDER; Color: red
- Raindrops: Name: GM_RAINDROP; Color: blue - All GeoMESH layer properties can be modified using standard AutoCAD layer commands. GeoMESH recognizes these and continues to use these modified layers.
- Changed settings of GeoMESH system variables and GeoMESH layers can be saved in a separate AutoCAD file template. They are then available in modified form for other projects using this template.
- By default, GeoMESH uses the coordinates of the current user coordinate system (UCS).
- By default, GeoMESH groups all generated data. Single groups are formed for the individual program results (e.g., terrain points, terrain meshes, contour lines, etc.).
- This software is based on CDT (C++ library for constrained Delaunay triangulation): Copyright © 2019 Leica Geosystems Technology AB, Copyright © The CDT Contributors, Licensed under the MPL-2.0 license, https://github.com/artem-ogre/CDT.
Known Issues
- GeoMESH is currently only available in English.
- Caution: Command GMTEXTURE requires significant computer resources.
- Caution: Command GMXYZIN does not support text files with BOM (Byte Order Mark).
- GeoMESH 2.2 and above does not support point IDs anymore.
Contact
Author/Company Information
Support Information
We look forward to hearing from you. Give us info, tricks, and hints about bugs. We try to answer and help as soon as possible. Thank you for making GeoMESH better. Write us at: info@femursoft.com
Visit femursoft.com for more information.
Version History
| Version Number | Version Description |
|---|---|
|
2.6.0 |
- New command GMRAINDROP. Allows for the simulation of rainwater flow (raindrops) on terrain meshes. If CWRITEMODE is set to 2, all raindrop flows are drawn as splines. Any endpoint (border reached or no further flow possible) of a raindrop flow is signed by a point (POINT). Note: This command is beta. - Command GMCONTOUR now creates 2D polylines (POLYLINE) by default. If the ISO3DMODE system variable is set to 'true', GMCONTOUR creates still 3D polylines (3DPOLY). - Command GMLINE2PLINE always attempts to construct and draw 2D polylines (POLYLINE) if the selected lines (LINE) are coplanar. If the selected lines are not coplanar or the ISO3DMODE system variable is set to 'true', GMLINE2PLINE draws 3D polylines (3DPOLY). - GeoMESH now supports AutoCAD 2026. - Changed contact data. - Bug fixes. |
|
2.5.0 |
- Extreme performance increase (e.g. till 4x faster with 8 available cores)! Important GeoMESH commands (GMCONTOUR, GMISOCONTOUR, GMTEXTURE, GMVOLUME and GMSURFACE) now use all available CPU cores for internal GeoMESH algorithms! Important: AutoCAD is not thread-save! This means that all routines for interacting with the AutoCAD database are still single-threaded. - GeoMESH can now process up to 10 million terrain points (!!) in a single mesh. Important: AutoCAD needs sufficient computing power to process such a large amount of data. Upon request and for an additional charge, the maximum number of terrain points can be increased to 1073 million. Please contact support. - New GeoMESH system variable DETECTHOLE or GMSETDETECTHOLE. Value 0: GMESH produces a convex-hull. Value 1: GMESH removes all outer triangles until a boundary defined by constraints. Value 2: GMESH remove outer triangles and automatically detected holes. - Bug fixes. |
|
2.4.1 |
- Optimized mesh algorithm (command GMESH), using part on CDT (C++ library for Constrained Delaunay Triangulation, Copyright © 2019 Leica Geosystems Technology AB, Copyright © The CDT Contributors, Licensed under the MPL-2.0 license, 'https://github.com/artem-ogre/CDT'). - New command GMSETVAR to access all GeoMESH system variables. Works like AutoCAD command SETVAR. Direct access typing GMSET+"variable name" still possible. - Removed GeoMESH command GMHELP. Please use this website for help information about GeoMESH. - Removed GeoMESH system variable CALCMODE or GMSETCALCMODE. Only one fast and optimized mesh algorithm now available. - Removed GeoMESH system variable MAXDATA or GMSETMAXDATA. New general data limit is 10e7 terrain points, in Trial-mode 100 terrain points. - Removed GeoMESH system variable GROUPMODE or GMSETGROUPMODE. Use AutoCAD system variable PICKSTYLE instead. GeoMESH creates now always groups. - Removed GeoMESH system variable UCSMODE or GMSETUCSMODE. GeoMESH uses now always the current UCS. - Modified GeoMESH system variable CINCR or GMSETCINCR. No more negative values allowed. - Modified GeoMESH system variable VOLPREC or GMSETVOLPREC. No more negative values allowed. Use instead the new GeoMESH system variable VOLDRAW. - New GeoMESH system variable VOLDRAW or GMSETVOLDRAW. Switch for rendering volume bodies using the GMVOLUME command. - Bug fixes. |
|
2.4.0 |
The trial version of GeoMESH 2.4.0 provides full functionality with a limitation of 100 terrain points. |
