Examples

This chapter contains example programs for the ledstrip written in RGBLang. You can also use it as a tutorial because the programs get more complicated each step.

Solid color

The following program sets every led on the ledstrip to a bright red.

// This will be executed for each led
r = 255
g = 0
b = 0

The r, g and b variables contain the red green and blue values for the current led on the led strip. You can read and write these. These variables are bytes, this means they have a minumim value of 0 and a maximum value of 255. Do not assign negative values to these! This will cause an integer overflow (-1 will be 255, -2 will be 254 …), this is probably not what you want.

Gradient

To create more complex effects, you can use the index variable, which contains the index of the led on the ledstrip for which the program is currently executing.

// index can be 0 - 784 if your ledstrip contains 784 leds
r = 0
g = index / 3 // Divide by 3 to match 255 as max green value
b = 0

This code shows a gradient from black to green.

Moving animation

To create moving animations, you should use the builtin timer variable. This variable contains the amount of milliseconds since the program has started running.

r = 0
g = 0
// Limit timer to 0 - 255 using modulus
b = timer % 255

This will show a flashing blue color. This is a rather sudden transition, it is better to use the builtin sin() function to create a smooth transition from blue to black:

r = 0
g = 0
b = sin(timer)

You can also use the cos() function, look here for a list of builtin utility functions.

Combine timer and index

You can combine the index and timer variables to create epic 😎 animations.

This animation shows a moving red wave:

// index contains n-th led, timer increases each frame
r = sin(index * 10 + timer / 10)
g = 0
b = 0

This animation moves a single red dot from the start of the ledstrip to the end:

b = 0
g = 0
if (index == (timer / 50) % 30) {
    // Create dot
    r = 255
}
else  {
    // Trail effect
    // r - 10 can be negative, which will cause problems
    // use the max function to ensure it is at least 0
    r = max(r - 10, 0)
}