This feature allows you to use RGB LED matrices driven by external drivers. It hooks into the RGBLIGHT system so you can use the same keycodes as RGBLIGHT to control it.
If you want to use single color LED's you should use the [LED Matrix Subsystem](feature_led_matrix.md) instead.
!> Note the parentheses, this is so when `DRIVER_LED_TOTAL` is used in code and expanded, the values are added together before any additional math is applied to them. As an example, `rand() % (DRIVER_1_LED_TOTAL + DRIVER_2_LED_TOTAL)` will give very different results than `rand() % DRIVER_1_LED_TOTAL + DRIVER_2_LED_TOTAL`.
Where `Cx_y` is the location of the LED in the matrix defined by [the datasheet](http://www.issi.com/WW/pdf/31FL3731.pdf) and the header file `drivers/issi/is31fl3731.h`. The `driver` is the index of the driver you defined in your `config.h` (`0` or `1` right now).
Where `X_Y` is the location of the LED in the matrix defined by [the datasheet](http://www.issi.com/WW/pdf/31FL3733.pdf) and the header file `drivers/issi/is31fl3733.h`. The `driver` is the index of the driver you defined in your `config.h` (Only `0` right now).
There is basic support for addressable RGB matrix lighting with a WS2811/WS2812{a,b,c} addressable LED strand. To enable it, add this to your `rules.mk`:
From this point forward the configuration is the same for all the drivers. The `led_config_t` struct provides a key electrical matrix to led index lookup table, what the physical position of each LED is on the board, and what type of key or usage the LED if the LED represents. Here is a brief example:
The first part, `// Key Matrix to LED Index`, tells the system what key this LED represents by using the key's electrical matrix row & col. The second part, `// LED Index to Physical Position` represents the LED's physical `{ x, y }` position on the keyboard. The default expected range of values for `{ x, y }` is the inclusive range `{ 0..224, 0..64 }`. This default expected range is due to effects that calculate the center of the keyboard for their animations. The easiest way to calculate these positions is imagine your keyboard is a grid, and the top left of the keyboard represents `{ x, y }` coordinate `{ 0, 0 }` and the bottom right of your keyboard represents `{ 224, 64 }`. Using this as a basis, you can use the following formula to calculate the physical position:
Where NUMBER_OF_COLS, NUMBER_OF_ROWS, COL_POSITION, & ROW_POSITION are all based on the physical layout of your keyboard, not the electrical layout.
As mentioned earlier, the center of the keyboard by default is expected to be `{ 112, 32 }`, but this can be changed if you want to more accurately calculate the LED's physical `{ x, y }` positions. Keyboard designers can implement `#define RGB_MATRIX_CENTER { 112, 32 }` in their config.h file with the new center point of the keyboard, or where they want it to be allowing more possibilities for the `{ x, y }` values. Do note that the maximum value for x or y is 255, and the recommended maximum is 224 as this gives animations runoff room before they reset.
All effects have been configured to support current configuration values (Hue, Saturation, Value, & Speed) unless otherwise noted below. These are the effects that are currently available:
```C
enum rgb_matrix_effects {
RGB_MATRIX_NONE = 0,
RGB_MATRIX_SOLID_COLOR = 1, // Static single hue, no speed support
RGB_MATRIX_ALPHAS_MODS, // Static dual hue, speed is hue for secondary hue
RGB_MATRIX_GRADIENT_UP_DOWN, // Static gradient top to bottom, speed controls how much gradient changes
RGB_MATRIX_BREATHING, // Single hue brightness cycling animation
By setting `RGB_MATRIX_CUSTOM_USER` (and/or `RGB_MATRIX_CUSTOM_KB`) in `rule.mk`, new effects can be defined directly from userspace, without having to edit any QMK core files.
To declare new effects, create a new `rgb_matrix_user/kb.inc` that looks something like this:
#define RGB_MATRIX_KEYPRESSES // reacts to keypresses
#define RGB_MATRIX_KEYRELEASES // reacts to keyreleases (instead of keypresses)
#define RGB_DISABLE_AFTER_TIMEOUT 0 // number of ticks to wait until disabling effects
#define RGB_DISABLE_WHEN_USB_SUSPENDED false // turn off effects when suspended
#define RGB_MATRIX_LED_PROCESS_LIMIT (DRIVER_LED_TOTAL + 4) / 5 // limits the number of LEDs to process in an animation per task run (increases keyboard responsiveness)
#define RGB_MATRIX_LED_FLUSH_LIMIT 16 // limits in milliseconds how frequently an animation will update the LEDs. 16 (16ms) is equivalent to limiting to 60fps (increases keyboard responsiveness)
#define RGB_MATRIX_MAXIMUM_BRIGHTNESS 200 // limits maximum brightness of LEDs to 200 out of 255. If not defined maximum brightness is set to 255
The EEPROM for it is currently shared with the RGBLIGHT system (it's generally assumed only one RGB would be used at a time), but could be configured to use its own 32bit address with:
