我找不到我在这里遗漏了什么，为什么会出现此错误？未捕获的 ReferenceError:未定义 createShaderFromScriptElement
我从一个常见的教程中得到这个并粘贴它。浏览器:Firefox 和 Chrome --> 两种浏览器都出现同样的错误
<!DOCTYPE HTML>
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Zooming via HTML5 Canvas Context</title>
</head>
<body>
<canvas id="canvas" width="200" height="200"></canvas>
<script id="2d-vertex-shader" type="x-shader/x-vertex">
attribute vec2 a_position;
void main() {
gl_Position = vec4(a_position, 0, 1);
}
</script>
<script id="2d-fragment-shader" type="x-shader/x-fragment">
void main() {
gl_FragColor = vec4(0,1,0,1); // green
}
</script>
<script>
window.onload = function() {
// Get A WebGL context
var canvas = document.getElementById("canvas");
var gl = canvas.getContext("experimental-webgl");
// setup a GLSL program
var vertexShader = createShaderFromScriptElement(gl, "2d-vertex-shader");
var fragmentShader = createShaderFromScriptElement(gl, "2d-fragment-shader");
var program = createProgram(gl, [vertexShader, fragmentShader]);
gl.useProgram(program);
// look up where the vertex data needs to go.
var positionLocation = gl.getAttribLocation(program, "a_position");
// Create a buffer and put a single clipspace rectangle in
// it (2 triangles)
var buffer = gl.createBuffer();
gl.bindBuffer(gl.ARRAY_BUFFER, buffer);
gl.bufferData(
gl.ARRAY_BUFFER,
new Float32Array([
-1.0, -1.0,
1.0, -1.0,
-1.0, 1.0,
-1.0, 1.0,
1.0, -1.0,
1.0, 1.0]),
gl.STATIC_DRAW);
gl.enableVertexAttribArray(positionLocation);
gl.vertexAttribPointer(positionLocation, 2, gl.FLOAT, false, 0, 0);
// draw
gl.drawArrays(gl.TRIANGLES, 0, 6);
}
</script>
</body>
</html>
最佳答案
createShaderFromScript 是外部脚本的一部分，而不是内置脚本。
无论您查看的是什么演示，都可能包含一个 webgl-utils 文件，如下所示:
http://greggman.github.com/webgl-fundamentals/webgl/resources/webgl-utils.js
它定义了一个 createShaderFromScript。
关于javascript - Webgl 未捕获引用错误 : createShaderFromScriptElement is not defined，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/13358924/