<!--
Copyright (c) 2019 The Khronos Group Inc.
Use of this source code is governed by an MIT-style license that can be
found in the LICENSE.txt file.
-->

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Float32Array garbage collection test</title>
<link rel="stylesheet" href="../resources/js-test-style.css"/>
<script src="../js/js-test-pre.js"></script>
<script src="../js/webgl-test-utils.js"> </script>
</head>
<body>
<canvas id="canvas" width="40" height="40"></canvas>
<div id="description"></div>
<div id="console"></div>
<script id="vshader" type="x-shader/x-vertex">
attribute vec2 inPosition;
attribute vec4 inColor;

varying vec4 color;

void main()
{
    color = inColor;

    gl_Position = vec4(inPosition, 0.0, 1.0);
}
</script>
<script id="fshader" type="x-shader/x-fragment">
precision mediump float;

varying vec4 color;

void main()
{
    if (color == vec4(0.0))
        discard;

    gl_FragColor = color;
}
</script>

<script>
"use strict";

description("Allocates a buffer object and then updates it repeatedly using throw-away Float32Array objects. " +
            "Ideally, this should not result in a browser crash or instability, since GC should be able to collect all Float32Arrays.");
var wtu = WebGLTestUtils;

var vertices = [];
var w = 0.25;
for (var x = -1; x < 1; x += w) {
    for (var y = -1; y < 1; y += w) {
        vertices.push(x + w, y + w);
        vertices.push(x,     y + w);
        vertices.push(x,     y    );

        vertices.push(x + w, y + w);
        vertices.push(x,     y    );
        vertices.push(x + w, y    );
    }
}
var numVertices = (vertices.length / 2);

var gl;
var squareBuffer;
var buffer;
var updateBufferData;
var drawIterationsPerTest = 100;

function initGL() {
    gl = wtu.create3DContext("canvas");
    var attribs = ["inPosition", "inColor"];
    wtu.setupProgram(gl, ["vshader", "fshader"], attribs);
    gl.disable(gl.DEPTH_TEST);
    gl.disable(gl.BLEND);

    squareBuffer = gl.createBuffer();
    gl.enableVertexAttribArray(0);
    gl.bindBuffer(gl.ARRAY_BUFFER, squareBuffer);
    gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(vertices), gl.STATIC_DRAW);
    gl.vertexAttribPointer(0, 2, gl.FLOAT, false, 0, 0);

    buffer = gl.createBuffer();
    gl.enableVertexAttribArray(1);
    gl.bindBuffer(gl.ARRAY_BUFFER, buffer);
    gl.vertexAttribPointer(1, 4, gl.FLOAT, false, 0, 0);
}

var testIndex = -1;
var drawIterations = 0;
var size = 0;
function runNextTest() {
    ++testIndex;
    var prevSize = size;
    size = Math.pow(2, testIndex) * numVertices * 16;

    if (size > 2 * 1024 * 1024 && prevSize <= 2 * 1024 * 1024) {
        if (!confirm("The following tests can cause unresponsiveness or instability. Press OK to continue.")) {
            testFailed("Tests aborted");
            return;
        }
    }

    if (size > 64 * 1024 * 1024) {
        gl.deleteBuffer(buffer);
        testPassed("Tests finished");
        return;
    }

    debug('Initializing buffer with size: ' + size);
    gl.bindBuffer(gl.ARRAY_BUFFER, buffer);
    gl.bufferData(gl.ARRAY_BUFFER, size, gl.DYNAMIC_DRAW);
    updateBufferData = new Float32Array(size / 4);

    debug("Drawing " + drawIterationsPerTest + " times, each time creating a new throw-away Float32Array of size " + size + " and using it to update the buffer");
    drawIterations = 0;
    doDraw();
};

var doDraw = function() {
    gl.clearColor(0, 255, 0, 255);
    gl.clear(gl.COLOR_BUFFER_BIT);

    // Update the array buffer with a throw-away Float32Array
    gl.bindBuffer(gl.ARRAY_BUFFER, buffer);
    gl.bufferSubData(gl.ARRAY_BUFFER, 0, new Float32Array(updateBufferData));

    gl.drawArrays(gl.TRIANGLES, 0, numVertices);
    var error = gl.getError();
    if (error !== gl.NO_ERROR) {
        testFailed("drawArrays failed with error " + wtu.glEnumToString(gl, error));
        return;
    }
    if (drawIterations < drawIterationsPerTest) {
        ++drawIterations;
        requestAnimationFrame(doDraw);
    } else {
        runNextTest();
    }
};

initGL();
runNextTest();

var successfullyParsed = true;
</script>

</body>
</html>

