scrawl-canvas
Version:
Version 8.9.4 - 19 Nov 2022
119 lines (96 loc) • 4.42 kB
HTML
<html>
<head>
<meta charset="utf-8">
<meta http-equiv="x-ua-compatible" content="ie=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Demo Filters 101</title>
<link href="css/normalize.css" rel="stylesheet" />
<link href="css/tests.css" rel="stylesheet" />
<style>
#my-image-store {
display: none;
}
.controls {
grid-template-columns: 1fr 2fr 1fr 2fr;
}
</style>
</head>
<body>
<h1><a href="index.html">Scrawl-canvas v8</a> - Filters test 101</h1>
<h2>Using assets in the filter stream; filter compositing</h2>
<h3>To change image, drag-and-drop an image file over the canvas</h3>
<div class="controls">
<div class="yellow label">Line IN</div>
<div class="yellow">
<select class="controlItem" id="source">
<option value="source">source</option>
<option value="source-alpha">source-alpha</option>
<option value="star">star</option>
<option value="wheel">wheel</option>
<option value="flower">flower</option>
</select>
</div>
<div class="yellow label">Line MIX</div>
<div class="yellow">
<select class="controlItem" id="destination">
<option value="source">source</option>
<option value="source-alpha">source-alpha</option>
<option value="star">star</option>
<option value="wheel">wheel</option>
<option value="flower">flower</option>
</select>
</div>
<div class="yellow label">Composite operation</div>
<div class="yellow">
<select class="controlItem" id="composite">
<option value="source-over">source-over</option>
<option value="source-in">source-in</option>
<option value="source-out">source-out</option>
<option value="source-atop">source-atop</option>
<option value="source-only">source-only</option>
<option value="destination-over">destination-over</option>
<option value="destination-in">destination-in</option>
<option value="destination-out">destination-out</option>
<option value="destination-atop">destination-atop</option>
<option value="destination-only">destination-only</option>
<option value="xor">xor</option>
<option value="clear">clear</option>
</select>
</div>
<div class="lavender label">Opacity</div>
<div class="lavender"><input class="controlItem" id="opacity" type="range" value="1" min="0" max="1" step="0.01" /></div>
<div class="pink label">Offset - X</div>
<div class="pink"><input class="controlItem" id="offset-x" type="range" value="30" min="-250" max="250" step="1" /></div>
<div class="pink label">Offset - Y</div>
<div class="pink"><input class="controlItem" id="offset-y" type="range" value="30" min="-250" max="250" step="1" /></div>
</div>
<canvas
id="mycanvas"
width="400"
height="400"
data-scrawl-canvas
></canvas>
<p id="reportmessage"></p>
<div class="testinfo">
<h4>Test purpose</h4>
<ul>
<li>Create two Cells which we can use to generate images for the filter</li>
<li>Load an additional image from the DOM</li>
<li>For each of our assets, create an image filter to load the assets into the filter pipeline</li>
<li>Create a compositing filter</li>
<li>Create a Block entity, using a gradient for its fill, and apply the compositing filter to it</li>
<li>Update the filter's lineIn and lineMix attributes and note the effect</li>
<li>Update the composite operation, check that the choice changes the display appropriately</li>
<li>In particular make sure the lineMix asset moves when the filter offset values are updated</li>
</ul>
<p>Note that filter memoization would provide no benefit in this demo because of the way we include the (rotating) cell-based wheel image filter in the display block filters array, even though that filter will only be displayed (as part of the compositing filter) if selected. Moral: only load process-image filters into a filter array if you intend to use them!</p>
<p><b>Touch test:</b> not required</p>
<p><a href="../docs/demo/filters-101.html">Annotated code</a></p>
</div>
<div id="my-image-store">
<img id="iris" src="img/iris.png" class="flowers" />
</div>
<script src="filters-101.js" type="module"></script>
</body>
</html>