Playable code
by booktu8
HTML
<!-- Learn about this code on MDN: https://developer.mozilla.org/zh-CN/docs/Web/API/CanvasRenderingContext2D/isPointInStroke -->
<canvas id="canvas" width="400" height="200" class="playable-canvas"></canvas>
<div class="playable-buttons">
<input id="edit" type="button" value="Edit" />
<input id="reset" type="button" value="Reset" />
</div>
<textarea id="code" class="playable-code">
ctx.rect(10, 10, 100, 100);
ctx.stroke();
console.log(ctx.isPointInStroke(10, 10)); // true</textarea>
JavaScript
var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");
var textarea = document.getElementById("code");
var reset = document.getElementById("reset");
var edit = document.getElementById("edit");
var code = textarea.value;
function drawCanvas() {
ctx.clearRect(0, 0, canvas.width, canvas.height);
eval(textarea.value);
}
reset.addEventListener("click", function() {
textarea.value = code;
drawCanvas();
});
edit.addEventListener("click", function() {
//textarea.focus();
console.log(ctx.isPointInStroke(10, 10));
})
textarea.addEventListener("input", drawCanvas);
window.addEventListener("load", drawCanvas);