Tsparticles: Help undestanding particles.number

[hidarikani]

Since I can't find docs for particles.number I've tried experimenting with the demo editor to figure out the settings. I've enabled the "More" > "Toggle Stats" option to see the current particle number. Unfortunately I still can't seem to understand the config options.

Why does the following config render 18 particles on the screen (according to the stats box)? My expectation is 10 rendered particles.

"number": {
  "density": {
    "enable": false,
    "area": 800,
    "factor": 1000
  },
  "limit": 0,
  "value": 10
}

Why does the following config render 2 particles on the screen (according to the stats box)? My expectation is 1 rendered particle.

"number": {
  "density": {
    "enable": false,
    "area": 800,
    "factor": 1000
  },
  "limit": 1,
  "value": 10
}

What is the unit of density.area. Is it the number of particles per 800x800 pixels?
What does the density.factor mean?

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[matteobruni]

Hi @hidarikani,

Those values are used in the formula used here

this.density = (canvas.width * canvas.height) / (densityOptions.factor * pxRatio * densityOptions.area);

// this.density will be multiplied with the particles.number value

This formula is inherited from particles.js changing a hard coded value with a customizable factor.

Disabling the density should use only the value for the count, if it’s not it’s a bug I need to investigate