Shadertoy

This is a Shadertoy implementation based on wgpu-py.

Introduction

This project provides a "screen pixel shader programming interface" similar to Shadertoy, enabling you to easily research, build, or test shaders using WGSL via WGPU.

It supports both WGSL and GLSL shaders. You can almost directly copy code from the Shadertoy website and run it.

Installation

To install the package, use the following command:

pip install https://github.com/panxinmiao/shadertoy/archive/main.zip

For development or installation from the source code:

git clone https://github.com/panxinmiao/shadertoy.git
cd shadertoy
pip install -e .

You probably also want to install glfw (or other gui backends).

pip install glfw

Please check the installation instructions of wgpu-py for details.

If you want to use the Audio features (AudioChannel or SoundPass), you also need to install the sounddevice and soundfile packages:

pip install sounddevice
pip install soundfile

Usage

The Shadertoy class takes a shader code string as input, and you can use the show method to display the shader in a window.

Basic Example:

from shadertoy import Shadertoy

main_code = """
fn shader_main(frag_coord: vec2<f32>) -> vec4<f32> {
    let uv = frag_coord / i_resolution.xy;

    if ( length(frag_coord - i_mouse.xy) < 20.0 ) {
        return vec4<f32>(0.0, 0.0, 0.0, 1.0);
    } else {
        return vec4<f32>( 0.5 + 0.5 * sin(i_time * vec3<f32>(uv, 1.0) ), 1.0);
    }
}
"""
shader = Shadertoy(main_code)
shader.show()

Using Channel Input:

from shadertoy import Shadertoy, DataChannel
import imageio.v3 as iio

# Load an image as a numpy array
noise_img = iio.imread("noise.png")

shader = Shadertoy(main_code)
shader.main_pass.channel_0 = DataChannel(noise_img)
shader.show()

Using AudioChannel:

Note: This requires the sounddevice and soundfile packages.

from shadertoy import Shadertoy
from shadertoy.audio import AudioChannel

shader = Shadertoy(main_code)
audio_channel = AudioChannel("audio.mp3")
shader.main_pass.channel_0 = audio_channel
audio_channel.play()  # Start playing the audio
shader.show()

Multiple Passes:

You can provide shader code for each pass, including sound passes. Configure the input channel of each pass, and you can set one pass as the channel for another pass, or even for itself.

from shadertoy import Shadertoy, DataChannel
import imageio.v3 as iio

shader = Shadertoy(
    main_code,
    common_code=common_code,
    buffer_a_code=buffer_a_code,
    buffer_b_code=buffer_b_code,
    sound_code=sound_code,  # The sound pass requires the `sounddevice` package
)

# Load an image as a numpy array
noise_img = iio.imread("noise.png")

# Configure channels for each pass
shader.buffer_a_pass.channel_0 = DataChannel(noise_img) # channel_0 is a texture
shader.buffer_a_pass.channel_1 = shader.buffer_a_pass  # channel_1 is the pass itself

shader.buffer_b_pass.channel_0 = shader.buffer_a_pass  # channel_0 is another pass

shader.main_pass.channel_0 = shader.buffer_b_pass
shader.main_pass.channel_1 = shader.buffer_a_pass
shader.show()

For more examples, please refer to the examples directory.