Target FPS/Refresh Rate

[dpuyosa]

For a project that Im working on the Raspberry I needed Smoothie to take less render time, so another WebGL canvas could get more FPS.

I made these changes so now I can find a balance between smoothness and performance.

this.chart = new Smooth.SmoothieChart({responsive: true, scaleSmoothing: 0.7});
this.chart.setTargetFPS(24);

It may be useful to someone else.

[drewnoakes]

Thanks very much. I pushed this in d88ff03 with some minor tweaks.