Practical sessions

Here are some additional suggestions to implement after you have finished reading:

• Adjust the ImGui window properties by using the window flags to disable properties such as the collapsing of the window, or the movement of it, and watch the result. You can find all supported flags in the imgui.h file.
• Change the checkbox to enable or disable vertical sync. This may be a bit tricky, as the UserInterface class may have no direct access to all the data you need. One idea to achieve this VSync change is toggling a Boolean variable in the OGLRenderData struct as a flag when the checkbox has been clicked and handling the change of this flag in the draw() method of the renderer.
• Add additional output to the ImGui window, such as the contents of the perspective and view matrix. You have to move them to the OGLRenderData / VkRenderData struct to access them from the UserInterface class. GLM has a glm::to_string() function, which works like std::to_string(...