Web applications are of great importance in the world of Internet and data exchange. A wide range of web application development technologies provides the ability to solve a wide range of problems. When solving a specific problem, it is of great importance to conduct a good analysis of which set of technologies to choose. To solve complex problems that require the processing of large amounts of data it is good to think outside the box. The standardization of protocols for communication between parts of applications via the Internet enables the connection of a standard architecture of web application and the possibility of accelerating complex data processing using native runtime technologies. This paper presents the use of the C++ programming language for creating the server part of the application in order to speed up data processing and mathematical calculations. To achieve the processing complexity, the problem to be solved is the interaction with the 3D object on the user interface. When the application is launched, a request is sent to the server side to retrieve object information for its display. By clicking on the object, the user selects the faces of the polygonal mesh. The coordinates of the click point are detected on the client side and sent to the server side together with the coordinates of camera. Iterating through a series of all faces of the object on server side, it is determined for each individual face whether it intersects with the line that goes through the two points obtained from the client side. In the case of an intersection, the face is detected as selected. In response, the indexes of selected faces are sent from the server side, and on the client side the selected faces within the polygonal mesh are colored using them. The aim of the paper is to achieve communication between the client side and the server side written in the C++ programming language. This opens the space for the use of C++ in the development of web applications in order to optimize and speed up complex calculations and data processing. Execution speed is a key factor to consider when developing a web application. This directly affects user satisfaction when using the application.