What is the best way to morph a pixel from one color to another?

Archive FastLED Archive
,
1

What is the best way to morph a pixel from one color to another?

I’d like to create a routine that can take a parameter of the number of steps to get from one CRGB value to another.

Is there anything in the library that can do this?

2

There’s a wide variety of blending functions defined in here - http://fastled.io/docs/3.1/colorutils_8h_source.html

3

This looks like this may do it but I wish there was a little more detailed info on usage:

CRGB blend ( const CRGB & p1,
const CRGB & p2,
fract8 amountOfP2
)

what is amountOfP2? On what scale is that measured?

CRGB* blend ( const CRGB * src1,
const CRGB * src2,
CRGB * dest,
uint16_t count,
fract8 amountOfsrc2
)

there’s not much documentation on the usage and parameters. What is count here?

4

For things like scaling and brightness and blending FastLED uses values from 0-255 as a percentage (why 0-255? Because it lets us keep the math fast).

So the parameter amountOfP2 is the “amount of p2” that you want in the final blended color - for example a value of 128 would give you a color that is 50% p1 and 50% p2. While a value of 64 would give you a color that is 75% p1 and 25% p2.

The second version is for when you want to blend two arrays of CRGB objects together - and “count” is passing in how many CRGB objects are in each array.

(The 0-255 scaling thing is documented in a number of places for the library and is a common enough thing that it isn’t added specifically to everywhere that it is used).

5

thanks for the clarification Daniel! Helpful as always