I'm getting started with A-Frame and this is a very basic question. I checked a number of examples to draw a line and then a curve in A-Frame but they don't show up in the scene. I have a plane there that shows up correctly.
I can use document.querySelector('a-plane').object3D; to get the plane but document.querySelector('a-curve').object3D; returns undefined.
Here is a code sample:
<!DOCTYPE html>
<html>
<head>
<title>A-frame room</title>
<script src="https://aframe.io/releases/0.5.0/aframe.min.js"></script>
</head>
<body>
<a-scene>
<a-plane position="0 0 -4" rotation="-90 0 0" width="4" height="4" color="#7BC8A4"> </a-plane>
<a-sky color="#ffffff"></a-sky>
<a-curve type="CatmullRom" curve="closed:true" visible="true">
<a-curve-point id="checkpoint1" position="0 0 -4" visible="true"></a-curve-point>
<a-curve-point id="checkpoint2" position="0 10 -4" visible="true"></a-curve-point>
<a-curve-point id="checkpoint3" position="0 10 -8" visible="true"></a-curve-point>
<a-curve-point id="checkpoint4" position="0 0 -8" visible="true"></a-curve-point>
</a-curve>
</a-scene>
</body>
</html>
You need to import the JS component that provides <a-curve>. It's a community component.