75 lines
2.2 KiB
HTML
75 lines
2.2 KiB
HTML
<!DOCTYPE HTML>
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<html>
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<head>
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<meta charset="utf-8">
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<style>
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#field {
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width: 200px;
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height: 150px;
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border: 10px solid black;
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background-color: #00FF00;
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position: relative;
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overflow: hidden;
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cursor: pointer;
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}
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#ball {
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position: absolute;
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left: 0;
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top: 0;
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width: 40px;
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height: 40px;
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transition: all 1s;
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}
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</style>
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</head>
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<body style="height:2000px">
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Click on a field to move the ball there.
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<br>
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<div id="field">
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<img src="https://en.js.cx/clipart/ball.svg" id="ball"> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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</div>
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<script>
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field.onclick = function(event) {
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// window-relative field coordinates
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let fieldCoords = this.getBoundingClientRect();
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// the ball has position:absolute, the field: position:relative
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// so ball coordinates are relative to the field inner left-upper corner
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let ballCoords = {
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top: event.clientY - fieldCoords.top - field.clientTop - ball.clientHeight / 2,
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left: event.clientX - fieldCoords.left - field.clientLeft - ball.clientWidth / 2
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};
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// prevent crossing the top field boundary
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if (ballCoords.top < 0) ballCoords.top = 0;
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// prevent crossing the left field boundary
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if (ballCoords.left < 0) ballCoords.left = 0;
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// // prevent crossing the right field boundary
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if (ballCoords.left + ball.clientWidth > field.clientWidth) {
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ballCoords.left = field.clientWidth - ball.clientWidth;
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}
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// prevent crossing the bottom field boundary
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if (ballCoords.top + ball.clientHeight > field.clientHeight) {
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ballCoords.top = field.clientHeight - ball.clientHeight;
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}
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ball.style.left = ballCoords.left + 'px';
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ball.style.top = ballCoords.top + 'px';
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}
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</script>
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</body>
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</html>
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