Make parallels denser at the poles where it makes a bigger difference
	The south pole looks really good with very dense vertices.
	The parallels should be the circles where the sphere would intersect with a series of concentric, evenly spaced cylinders.
Make the panning match the cursor
Enforce a minimum zoom that will keep the edges of the sphere from showing
	This probably just needs simple math with the aspect and/or the viewport's diagonal length.
Enforce a maximum zoom that matches the pixel density of the original image at its natural dimensions, normal to the camera
Choose a pleasant initial zoom
Allow pinch-zooming
Add data- attribute for minimum zoom
Add data- attribute for starting angle
Add data- attributes for canvas dimensions
Automatically create canvas for each marked <img> once it loads, and display:none the <img>
Set default canvas dimensions to match the size of the image
Add a class to the <canvas> for styling
Copy matrix funcs into code
Add licenses
Add instructions
Fix up code locality
Give the uniforms simpler names