Add Icon Sprites
The SVG icons are stored in a JSON object. They are text elements with Unicode values for symbols. Clicking the desired checkbox the the sprite as a text element and sends it to ThreeJS. Also, you can drag/drop the icon in SVG and it will updated in ThreeJS.

The SVG drawing overlays the ThreeJS canvas. You can toggle the SVG overlay visibility by selecting the 'Close SVG/Open SVG' button. When the SVG is closed the ThreeJS canvas is available for mousewheel/cursor control via the OrbitControls feature. The default view is CSS2DRenderer (SVG 2D) where the SVG icons remains fixed. You can select 'SVG 3D' button to place the SVG icons into the CSS3DRenderer where they will take on the perspective of the 3D environment.

SVG Source:

ThreeJS SVG Source:

Javascript SVG:

Javascript ThreeJS: