Splatterplot outliers twinkle when panning

[yelper]

This is decidedly not how the outliers should look; outlier points should be constant, regardless of the panning position. See the production version of SplatterJs: http://graphics.cs.wisc.edu/Projects/SplatterJs/

Diagnose the issue (code looks to be the same); check if points have constant z-value, if that z-value is being used by the shader, if the outlier shader is reading the correct texture and parameters, etc.