Q:

Drawing simple shapes or using sprites with OpenGL

I want to create a simple shape, let's say, a circle, it might have transparency, colors, etc. but it's still a simple circle.
In every tutorial I see, people use sprites. I am not sure what should I use for my case.
Should I use a sprite with a circle or should I try and draw the shape myself?
What are the advantages of each method?
Is there a line dividing them or is it just experience to know which one to use?

A:

GPU geometry is composed of triangles or line segments so it'll be inefficient to draw a circle in this way, it'll require too many triangles for it to look smooth.
The two more efficient ways to do that are:

Use a sprite
Use a shader and draw the circle. Check ShaderToy, more specifically the "Shapes" preset.

