Creating C++ Application

A UNIGINE-based application can be implemented by means of C++ only, without using UnigineScript.

This article describes how to add logic to your project by using the C++ language. Code written in C++ is the same for all supported platforms: Windows and Linux. The difference is in the way of compiling the project.

See also#

It is very easy to start your own C++ project by using UNIGINE SDK Browser:

1. Open the UNIGINE SDK Browser.
2. Go to the Projects tab and click CREATE NEW.
   
3. Specify the following parameters:
   
   • Project name — specify the name of your project.
   • Location — specify the path to your project folder.
   • SDK — choose the UNIGINE SDK edition.
   • API+IDE — choose C++ to start working with the C++ API.

     This parameter depends on a platform:

     • On Windows, you can create C++ Visual Studio 2022 project.
     • On Linux you can create C++ GNU make project.

     You can also can create C++ CMake project

   • Precision - specify the precision. In this example we will use double precision.
   Notice

   Read more about these parameters in this article
4. Click the CREATE NEW PROJECT button. The project will appear in the projects list.
   

You can run your project by clicking the Run button.

In this section we will add logic to the empty C++ application project.

The following example shows how to rotate the material ball that was created by default in your project.

1. If you created the C++ project for Visual Studio:

   1. Choose your C++ project in the UNIGINE SDK Browser and click the Open Code IDE button to open the project in IDE.
      

   If you created C++ GNU make project:

   1. On the created C++ project, click on the Other Actions button and then the Open Folder button.

      

   2. Go to the <YOUR PROJECT>\source\ folder and open the AppWorldLogic.cpp file with any plain text editor.
2. Write (or copy) the following code in your project's AppWorldLogic.cpp file.
   Source code (C++)

   #include "AppWorldLogic.h"
   #include <UnigineWorld.h>
   #include <UnigineGame.h>
   
   using namespace Unigine;
   
   // define pointer to node
   NodePtr node;
   
   AppWorldLogic::AppWorldLogic() {
   	
   }
   
   AppWorldLogic::~AppWorldLogic() {
   	
   }
   
   int AppWorldLogic::init() {
   	// get the material ball node
   	node = World::getNodeByName("material_ball");
   	return 1;
   }
   
   int AppWorldLogic::shutdown() {
   	return 1;
   }
   
   int AppWorldLogic::update() {
   	// get the frame duration
   	float ifps = Game::getIFps();
   
   	// set the angle of rotation
   	double angle = ifps * 90.0f;
   
   	// set the angle to the transformation matrix
   	Unigine::Math::Mat4 transform = node->getTransform();
   	transform.setRotateZ(angle);
   
   	// set new transformation to the node
   	node->setTransform(node->getTransform() * transform);
   
   	return 1;
   }
   
   int AppWorldLogic::postUpdate() {
   	return 1;
   }
   
   int AppWorldLogic::updatePhysics() {
   	return 1;
   }
   
   int AppWorldLogic::save(const Unigine::StreamPtr &stream) {
   	UNIGINE_UNUSED(stream);
   	return 1;
   }
   
   int AppWorldLogic::restore(const Unigine::StreamPtr &stream) {
   	UNIGINE_UNUSED(stream);
   	return 1;
   }

3. If you use Visual Studio, do the following:

   1. Before compiling your code, check that the appropriate platform and configuration settings for your project are set correctly.
      
   2. Build your project by clicking Build -> Build Solution in Visual Studio.
      
   3. Start your project by clicking Debug -> Start in a proper mode in Visual Studio.
      

   If you created a GNU Make project:

   1. Execute the make command in the terminal to compile the application.
      Shell commands

      make

   2. Launch the application by using the run script.