<!DOCTYPE HTML>
<html>
<body>
<script src="../../resources/js-test.js"></script>
<script type="text/javascript" src="canvas-blending-helpers.js"></script>
<script type="text/javascript">
description("Verify that reading back from a canvas2D multiple times without using willReadFrequently produces a console warning.");
const wrfCanvas = document.createElement("canvas");
const wrfCtx = wrfCanvas.getContext("2d", {willReadFrequently: true});
wrfCtx.fillStyle = "magenta";
wrfCtx.fillRect(0, 0, 10, 10);
const pixel1 = wrfCtx.getImageData(0, 0, 1, 1).data;
debug(`First pixel of canvas with willReadFrequently set to true: ${pixel1}`);
const pixel2 = wrfCtx.getImageData(20, 20, 1, 1).data;
debug(`Second pixel of canvas with willReadFrequently set to true: ${pixel2}`);
const nonWrfCanvas = document.createElement("canvas");
const nonWrfCtx = nonWrfCanvas.getContext("2d", {willReadFrequently: false});
nonWrfCtx.fillStyle = "magenta";
nonWrfCtx.fillRect(0, 0, 10, 10);
const pixel3 = nonWrfCtx.getImageData(0, 0, 1, 1).data;
debug(`First pixel of canvas with willReadFrequently set to false: ${pixel3}`);
const pixel4 = nonWrfCtx.getImageData(20, 20, 1, 1).data;
debug(`Second pixel of canvas with willReadFrequently set to false: ${pixel4}`);
const defWrfCanvas = document.createElement("canvas");
const defWrfCtx = defWrfCanvas.getContext("2d");
defWrfCtx.fillStyle = "magenta";
defWrfCtx.fillRect(0, 0, 10, 10);
const pixel5 = defWrfCtx.getImageData(0, 0, 1, 1).data;
debug(`First pixel of canvas with willReadFrequently not set: ${pixel5}`);
const pixel6 = defWrfCtx.getImageData(20, 20, 1, 1).data;
debug(`Second pixel of canvas with willReadFrequently not set: ${pixel6}`);
</script>
</body>
</html>
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