Rate Noise - AlbertGBarber/PixelSpork GitHub Wiki

See the Documentation Guide for help understanding each page section.

Description:

A utility that uses FastLED Perlin noise to produce a output value that varies randomly, but smoothly over time, and is locked to withing a set range. The output is intended to be used as an effect's update rate setting to randomly vary the effect's speed. However, there's nothing special about the output, it's just a uint16_t value, so you could easily use it for other purposes.

The output rate is stored as outputRate.

You can use the output rate in your effects like:

yourEffect.rate = &yourRateNoise.outputRate;
/* The line above binds an effect's "rate" setting to the "outputRate" of the utility
   Because the effect's update "rate" is a pointer, but the utility's outputRate is not, 
   we use "&" to bind it by address.
   Note that this means that both settings point to same place in memory
   If you want to change the effect's rate to something else, you'll need to bind it to a new variable. */

Note that you cannot use the outputRate in an effect's constructor, you must bind it after the effect has been created.

The utility only has a few settings. These can all be changed freely on the fly.

Notes:

  • FastLED noise tends to mostly fall in the center of it's range, so you may need to expand your min and max range values to have a "full" real range.

  • Because Perlin noise is not truly random (same input -> same output), to add an extra degree of variation I have introduced an extra random factor, randFact, which adds a slow shift to the noise. It's value is randomized on start up, but you may want to re-randomize it by calling setRandFact() when you first use the utility. You may also set randFact to 0 to ignore it entirely.

Example Calls:

RateNoisePS rateNoise(20, 120, 10, 80);
/*  Produces an output rate that varies smoothly between 20 and 120. 
    The speed multiplier of the noise is 10.
    The utility updates at a rate of 80ms. */

Constructor Definitions:

RateNoisePS(uint16_t RateMin, uint16_t RateMax, uint16_t NoiseSpeed, uint16_t Rate);

Constructor Inputs:

  • uint16_t rateMin -- The minimum possible value of the output rate.

  • uint16_t rateMax -- The maximum possible value of the output rate.

  • uint16_t noiseSpeed -- How quickly the output rate changes. Is a multiplier, so the effect amplifies at higher values. Recommend values between 5 - 40. Effects become very "jerky" at 100+. Higher -> faster rate change.

  • uint16_t* rate -- Update rate (ms). Is a pointer, allowing you to bind it to an external variable. By default it's bound the effect's local variable, rateOrig. See common vars rate entry for more. Note that a faster update rate will not increase how fast the noise changes, but will make it "smoother".

Outputs:

  • uint16_t outputRate -- The output rate of the utility (see intro).

Other Settings:

  • uint16_t randFact (set to a random value) -- A randomly set noise adjustment. Adds more variation to the noise output (see "Notes" above). Can be re-randomized by calling setRandFact(), or can be set manually. Setting it to 0 will remove its effect.

  • bool active (default true) -- If false, the utility/effect will be disabled (updates() will be ignored). See common vars active entry for more details.

Class Functions:

  • void setRandFact();

    Sets a new random randFact value.

  • void update();

    Updates the utility.