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compare the error messages to this

• passes: 1
• failures: 1
• duration: 0.06s

• buffer overflow tests

  • test buffer overflow with drawElements offset TypedArrays25ms ‣

    const {gl, tagObject} = createContext();
    const vs = `
    attribute vec4 position;
    void main() {
      gl_Position = position;
    }
    `;
    const fs = `
    precision mediump float;
    void main() {
      gl_FragColor = vec4(1, 0, 0, 1);
    }
    `;
    const prg = twgl.createProgram(gl, [vs, fs]);
    gl.useProgram(prg);
    function makeBuffer(gl, name, data, target = gl.ARRAY_BUFFER) {
      const buf = gl.createBuffer();
      tagObject(buf, name);
      gl.bindBuffer(target, buf);
      gl.bufferData(target, data, gl.STATIC_DRAW);
    }
    function makeBufferAndSetAttrib(gl, prg, name, size, data) {
      makeBuffer(gl, name, data);
      const loc = gl.getAttribLocation(prg, name);
      gl.enableVertexAttribArray(loc);
      gl.vertexAttribPointer(loc, size, gl.FLOAT, false, 0, 0);
    }
    const arrayBuffer = new ArrayBuffer(12 * 4 + 6 * 2);
    const positions = new Float32Array(arrayBuffer, 0, 12);
    const indices = new Uint16Array(arrayBuffer, 12 * 4, 6);
    positions.set([-1, 1, 0, 1, 1, 0, 1, -1, 0, -1, -1, 0]);
    indices.set([0, 1, 2, 0, 2, 3]);
    makeBufferAndSetAttrib(gl, prg, 'position', 3, positions);
    makeBuffer(gl, 'indices', indices, gl.ELEMENT_ARRAY_BUFFER);
    gl.useProgram(prg);
    // there was an internal bug not handling offset TypedArrays
    assertDoesNotThrow(() => {
      gl.drawElements(gl.TRIANGLES, 6, gl.UNSIGNED_SHORT, 0);
    });

  • test buffer overflow with drawElements offset TypedArrays using bufferSubData ‣

    Error: pixel at 0,0 expected: 0,255,0,255, was 0,0,0,0
        at checkDest (https://greggman.github.io/webgl-lint/test/webgl.js:67:17)
        at Context.<anonymous> (https://greggman.github.io/webgl-lint/test/tests/buffer-overflow-tests.js:273:5)
        at callFn (https://greggman.github.io/webgl-lint/test/mocha.js:13124:23)
        at Runnable$3.run (https://greggman.github.io/webgl-lint/test/mocha.js:13112:7)
        at Runner.runTest (https://greggman.github.io/webgl-lint/test/mocha.js:14657:12)
        at https://greggman.github.io/webgl-lint/test/mocha.js:14780:14
        at next (https://greggman.github.io/webgl-lint/test/mocha.js:14572:16)
        at https://greggman.github.io/webgl-lint/test/mocha.js:14582:9
        at next (https://greggman.github.io/webgl-lint/test/mocha.js:14465:16)
        at https://greggman.github.io/webgl-lint/test/mocha.js:14550:7

    const {gl, tagObject} = createContext();
    const vs = `
    attribute vec4 position;
    void main() {
      gl_Position = position;
    }
    `;
    const fs = `
    precision mediump float;
    void main() {
      gl_FragColor = vec4(0, 1, 0, 1);
    }
    `;
    const prg = twgl.createProgram(gl, [vs, fs]);
    gl.useProgram(prg);
    function makeBuffer(gl, name, data, target = gl.ARRAY_BUFFER) {
      const buf = gl.createBuffer();
      tagObject(buf, name);
      gl.bindBuffer(target, buf);
      gl.bufferData(target, data.byteLength, gl.STATIC_DRAW);
      gl.bufferSubData(target, 0, data);
    }
    function makeBufferAndSetAttrib(gl, prg, name, size, data) {
      makeBuffer(gl, name, data);
      const loc = gl.getAttribLocation(prg, name);
      gl.enableVertexAttribArray(loc);
      gl.vertexAttribPointer(loc, size, gl.FLOAT, false, 0, 0);
    }
    const arrayBuffer = new ArrayBuffer(12 * 4 + 6 * 2);
    const positions = new Float32Array(arrayBuffer, 0, 12);
    const indices = new Uint16Array(arrayBuffer, 12 * 4, 6);
    positions.set([
      -1,  1, 0,
       1,  1, 0,
       1, -1, 0,
      -1, -1, 0,
    ]);
    indices.set([0, 1, 2, 0, 2, 3]);
    makeBufferAndSetAttrib(gl, prg, 'position', 3, positions);
    makeBuffer(gl, 'indices', indices, gl.ELEMENT_ARRAY_BUFFER);
    gl.useProgram(prg);
    gl.clearColor(1, 0, 0, 1);
    gl.clear(gl.COLOR_BUFFER_BIT);
    gl.drawElements(gl.TRIANGLES, 6, gl.UNSIGNED_SHORT, 0);
    checkDest(gl, [0, 255, 0, 255]);