gdal.netcore

A simple (as is) build engine of GDAL library for .NET.

Provides a minimal setup without requirements to install heavy GDAL binaries into your system.

Packages (NuGet)

MaxRev.Gdal.Universal

MaxRev.Gdal.Core

MaxRev.Gdal.WindowsRuntime.Minimal

MaxRev.Gdal.LinuxRuntime.Minimal

• MaxRev.Gdal.LinuxRuntime.Minimal.x64
  
• MaxRev.Gdal.LinuxRuntime.Minimal.arm64
  

MaxRev.Gdal.MacosRuntime.Minimal

• MaxRev.Gdal.MacosRuntime.Minimal.x64
  
• MaxRev.Gdal.MacosRuntime.Minimal.arm64

Table Of Contents

About this library

What is this library

• Only generates assemblies and binds everything into one package.
• Provides easy access to GDAL by installing only core and runtime package
• DOES NOT require installation of GDAL. From 3.7.0 version GDAL_DATA is also shipped. While it contains the proj.db database you may require proj-data grid shifts.

What is not

• Does not compile all drivers. Only configured, they are listed below. By default GDAL has a lot of internal drivers.
• Does not change GDAL source code.
• Does not extend GDAL methods.

How to use

Universal package

1. Install universal package - MaxRev.Gdal.Universal. It references all runtime packages and the core package. They will be automatically installed during restore. Note that this may increase the size of your nuget cache.

   dotnet add package MaxRev.Gdal.Universal

Separate core and runtime packages

1. Install core package - MaxRev.Gdal.Core

   dotnet add package MaxRev.Gdal.Core

2. Install libraries for your runtime. You can install one of them or all with no conflicts. There is no requirement to install all of them or GDAL binaries. If you work on Windows and Linux you can skip MacOS package and vice versa.

   
   # windows supported only for x64
   dotnet add package MaxRev.Gdal.WindowsRuntime.Minimal 

install linux bundle which references both arm64 and x64 binaries

dotnet add package MaxRev.Gdal.LinuxRuntime.Minimal

or install a specific runtime

dotnet add package MaxRev.Gdal.LinuxRuntime.Minimal.arm64 dotnet add package MaxRev.Gdal.LinuxRuntime.Minimal.x64

install macos bundle which references both arm64 and x64 binaries

dotnet add package MaxRev.Gdal.MacosRuntime.Minimal

or install a specific runtime

dotnet add package MaxRev.Gdal.MacosRuntime.Minimal.arm64 dotnet add package MaxRev.Gdal.MacosRuntime.Minimal.x64

### Initialize libraries in runtime
```csharp
using MaxRev.Gdal.Core;
// call it once, before using GDAL
// this will initialize all GDAL drivers and set PROJ6 shared library paths
GdalBase.ConfigureAll();

4. Profit! Use it in ordinary flow. See the section below for more info.

Supported runtimes

• Windows x64 (.NET Framework 4.6.1+, .NET Standard 2.0+, .NET 6/7/8+)
• Linux x64/arm64 (.NET Framework 4.6.1+, .NET Standard 2.0+, .NET 6/7/8+)
• MacOS x64/arm64 (.NET Framework 4.6.1+, .NET Standard 2.0+, .NET 6/7/8+)

This means you can build .NET Framework applications on Linux/MacOS using Mono. Also, any project based on NET Standard 2.0 or higher can utilize this library.

Using GDAL functions

If you're struggling using GDAL functions. Here's a good place to start:

• Vector related operations
• Raster related operations
• Sample Apps

Development

How to compile on Windows

Enter win directory to find out how.

How to compile on Unix

Detailed guide is here - unix.

How to compile on macOS

Detailed guide is here - osx.

About build configuration

The package configuration is marked as minimal. That means you don't have to install GDAL binaries. Also, some uncommon drivers are not available (were not built).

Drivers included PROJ, GEOS, and more than 200 other drivers.

To view the complete list of drivers, see: tests/gdal-formats/supported_drivers.md.

NOTE: Runtime drivers availability may differ. Ask me about a specific driver for runtime. Please issue if I need to mention any packages.

Starting version 3.9.0 the packages can be compiled and run on .NET Framework 4.6.1+. The libraries and gdal-data will be automatically copied to the output directory. See tests/MaxRev.Gdal.Core.Tests.NetFramework for more info.

Building runtime libraries

Each runtime has to be build separately, but this can be done concurrently as they are using different contexts (build folders). Primary operating bindings (in gdal.core package) are build from windows. Still, the resulting core bindings are the same on each runtime package (OS).

To make everything work smoothly, each configuration targets the same drivers and their versions, respectively.

To start building for a specific runtime, see the README.md in a respective directory.

FAQ

Q: Packages does not work on CentOS 7, Ubuntu 18.04

A: These are old distros and are out of support (EOL). Use docker (see this Dockerfile how to package your app) or a newer distro (GLIBC 2.31+). Packages for older systems are difficult to maintain. From 3.6.x version the Debian 11 distro is used. See this for more info.

Q: Can I compile it on Ubuntu or another Unix-based system?

A: Yes, you can (see unix folder for readme). All you have to do, is to choose one of the latest distros like Ubuntu 22.04 or Debian 11 (recommended). From the 3.6.x version the Debian 11 distro is used by default. It was changed because of EOL of the previous distro (see answer above). Prior to 3.6.x version packages were built on CentOS - glibc of version 2.17. It's the lowest version (in my opinion) that suits all common systems (Ubuntu, Debian, Fedora).

Q: Projections are not working as expected

A: This package only contains the proj.db database. Make sure you have installed proj-data package. It contains aditional grid shifts and other data required for projections. Add path to your data folder with MaxRev.Gdal.Core.Proj.Configure(). See this for more info.

Q: Some drivers complain about missing data files

A: This is related to the previous package versions (prior to 3.7.0). From 3.7.0 version, GDAL_DATA folder is also shipped with core package.

Q: Missing {some} drivers, can you add more?

A: Feel free to contribute and I will help you you to add them. Here's the my additional answer.

Q: GDAL functions are not working as expected

A: Try to search an issue on github. In 98% of cases, they are working fine.

Q: Some types throw exceptions from SWIG on Windows

A: Yes, currently there are some redundant types in OGR namespace. This will be fixed in the next builds.

Q: In some methods performance is slower on Unix

A: Apparently, it's not a fault of the build engine. I did not face this issue and I use this packages in several production environments.

Q: OSGeo.OGR.SpatialReference throws System.EntryPointNotFoundException exception

A: That's a problem with swig bindings. Please, use SpatialReference type from OSR namespace. More info here and here.

Q: Packages does not work on MacOS Catalina or lower

A: The current version of packages was compiled on MacOS Ventura and 11.3 SDK respectively. Consider updating your system to at least MacOS 13. The systems that reached EOL (end-of-life) won't be supported.

Q: The first run on MacOS is slow and takes more than 3 seconds

A: It's a known issue related to the linking of the shared libraries. If you find any solution/workaround, please let me know. Currently, linker tries to find all shared libraries in the @loader_path/. It should point to the executable directory.

Q: BadImageFormatException on Windows

A: Ensure that you are using the same architecture for your project and the runtime package. If you are using AnyCPU, you should use only the x64 runtime package. See the sample project for details in tests/MaxRev.Gdal.Core.Tests.NetFramework.

Q: Publishing the project with runtime packages

A: There are several ways to publish. One important thing to keep in mind, that you have to ensure the output folder contains either runtimes/<os>-<arch>/native path, gdal-data folder and maxrev.gdal.core.libshared/proj.db. In most cases this should be handled automatically by dotnet. Usually, we release a runtime-dependent binary. The end user will have to install the .NET runtime, but the size of the app will be small and the build time is faster. Otherwise, you can publish a self-contained app which will include all required .NET runtime libraries. More details on publishing can be found here. Also, see the sample dockerized project for details in tests/MaxRev.Gdal.Core.Tests/Dockerfile.

About and Contacts

This work is based on GDAL and GDAL bindings by jgoday.

Contact me in Telegram - MaxRev.

Enjoy!

Acknowledgements

As the maintainer of this repository, I want to express my heartfelt thanks to Verge Agriculture Inc.. They generously provided the necessary resources that made compiling the macOS bindings and the latest versions of GDAL possible.