Recently tried HTML5 / Canvas / JavaScript. I copied with C ++ / OpenGL a simple particle system from my old game - gamediameter.sourceforge.net .
You can see what happened here: mjv-art.org/files/WebDiameter . By default there are 60 particles and they are oriented in the direction of the mouse cursor. In addition, the FPS value is displayed. In fact, the biggest problem was math, I didn’t immediately find a library for working with vectors for JavaScript. While writing his own and primitive.