ShaderCoder

Runtime error

File size: 6,693 Bytes

3f8d823


def construct_embed(source_url):
    shader_id = source_url.split("/")[-1]
    return f'<iframe width="640" height="360" frameborder="0" src="https://www.shadertoy.com/embed/{shader_id}?gui=true&t=0&paused=true&muted=true" allowfullscreen></iframe>'

def make_iframe(shader_code): #keep a single function?
     script = make_script(shader_code)
     return f"""<iframe width="640" height="420" srcdoc=\'{script}\' allowfullscreen></iframe>"""
    

def make_script(shader_code):
    # code copied and fixed(escaping single quotes to double quotes!!!) from https://webglfundamentals.org/webgl/webgl-shadertoy.html
    script = ("""
<!-- Licensed under a BSD license. See license.html for license -->
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=yes">
<title>WebGL - Shadertoy</title>
<link type="text/css" href="https://webglfundamentals.org/webgl/resources/webgl-tutorials.css" rel="stylesheet" />
<style>
.divcanvas {
  position: relative;
  display: inline-block;
} 
canvas {
  display: block;
}
.playpause {
  position: absolute;
  left: 10px;
  top: 10px;
  width: 100%;
  height: 100%;
  font-size: 60px;
  justify-content: center;
  align-items: center;
  color: rgba(255, 255, 255, 0.3);
  transition: opacity 0.2s ease-in-out;
}
.playpausehide,
.playpause:hover {
  opacity: 0;
}
.iframe .divcanvas {
  display: block;
}
</style>
</head>
<body>
<div class="divcanvas">
  <canvas id="canvas"></canvas>
  <div class="playpause">▶</div>
</div>
\nblank canvas here indicates that some of the shadertoy specific functions are not yet supported with this implementation (like #define I believe). you can always copy and paste the code into a shadertoy.com window to try.
</body>
<!--
for most samples webgl-utils only provides shader compiling/linking and
canvas resizing because why clutter the examples with code thats the same in every sample.
See https://webglfundamentals.org/webgl/lessons/webgl-boilerplate.html
and https://webglfundamentals.org/webgl/lessons/webgl-resizing-the-canvas.html
for webgl-utils, m3, m4, and webgl-lessons-ui.
-->
<script src="https://webglfundamentals.org/webgl/resources/webgl-utils.js"></script>
<script>
"use strict";

function main() {
  // Get A WebGL context
  /** @type {HTMLCanvasElement} */
  const canvas = document.querySelector("#canvas");
  const gl = canvas.getContext("webgl");
  if (!gl) {
    return;
  }

  const vs = `
    // an attribute will receive data from a buffer
    attribute vec4 a_position;

    // all shaders have a main function
    void main() {

      // gl_Position is a special variable a vertex shader
      // is responsible for setting
      gl_Position = a_position;
    }
  `;

  const fs = `
    precision highp float;

    uniform vec2 iResolution;
    uniform vec2 iMouse;
    uniform float iTime;

    """ + shader_code + """
    void main() {
      mainImage(gl_FragColor, gl_FragCoord.xy);
    }
  `;

  // setup GLSL program
  const program = webglUtils.createProgramFromSources(gl, [vs, fs]);

  // look up where the vertex data needs to go.
  const positionAttributeLocation = gl.getAttribLocation(program, "a_position");

  // look up uniform locations
  const resolutionLocation = gl.getUniformLocation(program, "iResolution");
  const mouseLocation = gl.getUniformLocation(program, "iMouse");
  const timeLocation = gl.getUniformLocation(program, "iTime");

  // Create a buffer to put three 2d clip space points in
  const positionBuffer = gl.createBuffer();

  // Bind it to ARRAY_BUFFER (think of it as ARRAY_BUFFER = positionBuffer)
  gl.bindBuffer(gl.ARRAY_BUFFER, positionBuffer);

  // fill it with a 2 triangles that cover clipspace
  gl.bufferData(gl.ARRAY_BUFFER, new Float32Array([
    -1, -1,  // first triangle
     1, -1,
    -1,  1,
    -1,  1,  // second triangle
     1, -1,
     1,  1,
  ]), gl.STATIC_DRAW);

  const playpauseElem = document.querySelector(".playpause");
  const inputElem = document.querySelector(".divcanvas");
  inputElem.addEventListener("mouseover", requestFrame);
  inputElem.addEventListener("mouseout", cancelFrame);

  let mouseX = 0;
  let mouseY = 0;

  function setMousePosition(e) {
    const rect = inputElem.getBoundingClientRect();
    mouseX = e.clientX - rect.left;
    mouseY = rect.height - (e.clientY - rect.top) - 1;  // bottom is 0 in WebGL
  }

  inputElem.addEventListener("mousemove", setMousePosition);
  inputElem.addEventListener("touchstart", (e) => {
    e.preventDefault();
    playpauseElem.classList.add("playpausehide");
    requestFrame();
  }, {passive: false});
  inputElem.addEventListener("touchmove", (e) => {
    e.preventDefault();
    setMousePosition(e.touches[0]);
  }, {passive: false});
  inputElem.addEventListener("touchend", (e) => {
    e.preventDefault();
    playpauseElem.classList.remove("playpausehide");
    cancelFrame();
  }, {passive: false});

  let requestId;
  function requestFrame() {
    if (!requestId) {
      requestId = requestAnimationFrame(render);
    }
  }
  function cancelFrame() {
    if (requestId) {
      cancelAnimationFrame(requestId);
      requestId = undefined;
    }
  }

  let then = 0;
  let time = 0;
  function render(now) {
    requestId = undefined;
    now *= 0.001;  // convert to seconds
    const elapsedTime = Math.min(now - then, 0.1);
    time += elapsedTime;
    then = now;

    webglUtils.resizeCanvasToDisplaySize(gl.canvas);

    // Tell WebGL how to convert from clip space to pixels
    gl.viewport(0, 0, gl.canvas.width, gl.canvas.height);

    // Tell it to use our program (pair of shaders)
    gl.useProgram(program);

    // Turn on the attribute
    gl.enableVertexAttribArray(positionAttributeLocation);

    // Bind the position buffer.
    gl.bindBuffer(gl.ARRAY_BUFFER, positionBuffer);

    // Tell the attribute how to get data out of positionBuffer (ARRAY_BUFFER)
    gl.vertexAttribPointer(
        positionAttributeLocation,
        2,          // 2 components per iteration
        gl.FLOAT,   // the data is 32bit floats
        false,      // dont normalize the data
        0,          // 0 = move forward size * sizeof(type) each iteration to get the next position
        0,          // start at the beginning of the buffer
    );

    gl.uniform2f(resolutionLocation, gl.canvas.width, gl.canvas.height);
    gl.uniform2f(mouseLocation, mouseX, mouseY);
    gl.uniform1f(timeLocation, time);

    gl.drawArrays(
        gl.TRIANGLES,
        0,     // offset
        6,     // num vertices to process
    );

    requestFrame();
  }

  requestFrame();
  requestAnimationFrame(cancelFrame);
}

main();
</script>
</html>


""")
    return script