How to download and setup hello_imgui
Open terminal and run command
                                            git clone https://github.com/Terkwood/hello_imgui.git
                                        
                                        git clone is used to create a copy or clone of hello_imgui repositories.
                                        You pass git clone a repository URL. it supports a few different network protocols and corresponding URL formats.
Also you may download zip file with hello_imgui https://github.com/Terkwood/hello_imgui/archive/master.zip
Or simply clone hello_imgui with SSH
                                            [email protected]:Terkwood/hello_imgui.git                                    
                                    If you have some problems with hello_imgui
You may open issue on hello_imgui support forum (system) here: https://github.com/Terkwood/hello_imgui/issuesSimilar to hello_imgui repositories
Here you may see hello_imgui alternatives and analogs
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