Water ripple effect and seabed distortion

Below GIF made with library PygameShader (GPU shader ==> wave_gpu method). Wave_gpu method is the cython method developped in this github page ported to CUDA for higher resolutions and better perforamces. For a full GPU demo install PygameShader(*) and run the demo PygameShader/Demo/GPU_demo_ripple.py

(*) refers to the dependencies section (CUDA must be installed).

Demo

This github page host the full CPU demo, please click on the new release version 1.0.2 as shown below

Click on the executable setup_RippleEffect.exe to download the installer and run it onto your machine, The installation process might be flagged as unsafe by your anti-virus.

Newest version

The most recent versions of the below algorithms are now integrated within the project PygameShader, and will be updated from that project only.

• Water ripple effect and seabed distortion (GPU)
• Surface water ripple effect (CPU method)

Various python/cython methods

This github page contains 3 different rendering methods.

1. Pure Python
2. Cython Version
3. OpenMP Version (Multi-processing)

Pure Python ver 3.6 - 3.9

In the pure python method I am using two different techniques

1. Iterating method

   Description : Iterating over all pixels values width x height and performing a blur on adjacent pixels
   performance result: Slow method and not usable for real time rendering for screen resolution above 100 x 100 pixels!. Python version 3.11 might provide better performances

2. Numpy arrays

   Description : Instead of going through all the pixels inside a loop and applying a blur for each pixels, the technique is to call separately the method numpy.roll for every directions (up, down, left, right) and sum all 4 numpy arrays. This provides the equivalent of blur effect for each pixels in only 4 operations.

   pixels	numpy	convolution direction
   (x, y + 1)	numpy.roll(previous, +1, axis=0)	down pass
   (x, y - 1)	numpy.roll(previous, -1, axis=0)	up pass
   (x + 1, y)	numpy.roll(previous, -1, axis=1)	left pass
   (x - 1, y)	numpy.roll(previous, +1, axis=1)	right pass

   performance Result : Using numpy array is 300 times faster than the pure python version, however this method is still not adequate for a real time rendering.

Cython and OpenMP rendering

The Cython version into the folder Cython and CythonOpenMP (multiprocessing) provide performance of 100 FPS for a screen 600 x 600 with water ripple effect with seabed distortion.

Requirement

• Pygame 3 (pip install pygame)
• Numpy (pip install numpy)
• Cython (refer to a tutorial to see how to install cython)
• A compiler such visual studio, MSVC, CGYWIN setup correctly on your system.
• a C compiler for windows (Visual Studio, MinGW etc) install on your system and linked to your windows environment. Note that some adjustment might be needed once a compiler is install on your system, refer to external documentation or tutorial in order to setup this process. e.g https://devblogs.microsoft.com/python/unable-to-find-vcvarsall-bat/

Build cython code

C:\>python setup_RippleEffect.py build_ext --inplace

When python has been compiled, run the program main_RippleEffect.py from your favorite python IDE.

Or run the demo executable where the fodler Asset has been copied: C:>demo.exe