This is a small C-SDL series about procedural textures.

The Code demonstrates how to...

• render noise (1).
• save a screenshot (1b).
• smooth noise (1c).
• add turbulence (1d).
• change turbulence with mousewheel (0-255) (1e).
• render Clouds - HSLtoRGB, change turbulence with mousewheel (0-255) (1f).
• generate a Marble Texture (1g).
• generate a Wood Texture (1h).
• add some more mathematical 2D functions (2).
           Use mousewheel to change drawing function.
• render 3D Random Noise animated with a function of time (3).

Press s to save the image.

Useful links:
Lode's Computer Graphics Tutorial - Texture Generation using Random Noise
      * parts of his code are used with permission.
                  SDL2 | SDL-Discourse | More SDL2 Example Code

Screenshots:

                                      Get in touch on SDL-Discourse

Annotation:
This Code is a tribute to Lode's Computer Graphics Tutorial which I appreciate very much.
A practical (concrete) primer into computer graphics.

                                                       *     *     *
Real time computation of those graphics are pretty cpu-heavy and way faster using the GPU.
You may consider a hardware accelerated API like Vulkan or OpenGL.