Shadows based on predetermined points. - This won't work with transparency, the shadows have to be opaque. I worked on this in my free time. I decided maybe I should share it with others. Feel free to use this! I recommend using straight lines with points instead of curves, as it requires much less computing power. Click the screen to place a point. I used a triangle filler made by someone (I forgot who), and I used those triangles to create filled shadows! In theory this could be blazing fast, if only Scratch had a "triangle fill" block...
