cables is under heavy development.
There might be one or another bug, please let us know about it!
cables Documentation      How To Use            Working with files            Keyboard Shortcuts            User Interface Walkthrough      Beginner Tutorial            Beginner 1: Drawing A Circle            Beginner 2: Transformations            Beginner 3: Color            More Transformations      intermediate            Image Compositions            Post-Processing 3D Scenes      communication            cables API            Communication with an Arduino via Serial            Communicating with Arduino over MQTT      Exporting And Embedding            How to serve files externally and fix CORS headers            Embedding Patches            External triggers / functions            Embedding Patches            Previewing / uploading exported cables patches      coding ops            Creating Attachments            General op/Port Callbacks            Ports                  Dynamic Ports                  Array Ports                  Boolean ports                  Integer Number Ports                  Object Ports                  String ports                  Trigger Ports                  Floating Point Number Ports            GUI/UI attributes            Hello Op - Part 1            Libraries            Developing Ops            Guidelines            Object Ports            Writing Shaders            Web Audio Op Development      HTML and CSS in cables      Lighting            Lights            Shadows      FAQ            Embedding                  How to remove grey rectangles on touch (mobile)?                  Why doesn't the DownloadTexture op work on iOS?                  How to disable page scrolling on mobile?                  Transparent Canvas            Features and Support                  Will there be support for (animated) GIFs?            General questions            Licences and payment                  What licence do i need to use cables?                  Will I have to pay for it in the future?                  How is my work licenced when using cables?            Does cables support midi and OSC?            Shadertoy            Technical questions            UI / Editor            WebGL1 and WebGL2


Go to this example page to see a basic setup of shadertoy in cables.
Youtube tutorial porting shadertoy to cables part 01

Porting shaders from shadertoy isn't that difficult once you know the basics.
The main ops that you'll need are:

standard glsl in shadertoy and the equivalent in cables is:

fragCoord.xy                                //pixel coordinates in shadertoy
gl_FragCoord.xy                             //pixel coordinates in cables

vec2 uv =  fragCoord/iResolution.xy;        // normalized pixel co-ordinates from 0-1 on shadertoy
IN vec2 texcoord                            // normalized pixel co-ordinates from 0-1 in cables,already created

The uniforms on shadertoy and their equivalent in cables are as follows:

uniform vec3      iResolution;              // viewport resolution (in pixels)
UNI vec3          iResolution;              // get width and height output from mainloop,canvasinfo for aspect ratio/z

uniform float     iTime;                    // shader playback time (in seconds)
UNI float         iTime;                    // Use the output of the timer op

uniform float     iTimeDelta;               // render time (in seconds)
UNI float         iTimeDelta;               // use the output of the TimeDelta op

uniform int       iFrame;                   // shader playback frame
UNI int           iFrame;                   // connect trigger counter to mainloop output

uniform float     iChannelTime[4];          // channel playback time (in seconds)
UNI float         iChannelTime0;            // get the current playtime from the relevant media op

uniform vec3      iChannelResolution[4];    // channel resolution (in pixels)
UNI vec3          iChannelResolution0..3;   // channel resolution (in pixels)

uniform samplerXX iChannel0..3;             // input channel. XX = 2D/Cube
UNI sampler2D     iChannel0..3;             // Creates a texture input which can be used

uniform vec4      iDate;                    // (year, month, day, time in seconds)
UNI vec4          iDate;                    // (year, month, day, time in seconds)

uniform float     iSampleRate;              // sound sample rate (i.e., 44100)
UNI float         iSampleRate;              // Use the audiobuffer op to access this

uniform vec4      iMouse;                   // mouse pixel coords. xy: current (if MLB down), zw: click
UNI vec4          iMouse                    // use mouse op. see example patch for in depth explanation.

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