Basic lighting in OpenGL

In this example, we will learn how to add a simple point light to our 3D scene by using OpenGL and Qt 6.

How to do it…

Let’s get started by following these steps:

1. Again, we will use the previous example and add a point light near the spinning cube. Open up renderwindow.h and add another variable called vbo_normals to the file:

       QOpenGLBuffer* vbo_uvs;
       QOpenGLBuffer* vbo_normals;
       QOpenGLTexture* texture;

2. Open renderwindow.cpp and add another array called normals to the initializeGL() function:

       GLfloat normals[] = {
        0.0f, -1.0f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f, -1.0f, 0.0f,
        0.0f, -1.0f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f, -1.0f, 0.0f,
        0.0f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f,
        0.0f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f...