qmk_firmware_custom/quantum/rgb_matrix_animations/rainbow_beacon_anim.h

#ifndef DISABLE_RGB_MATRIX_RAINBOW_BEACON
RGB_MATRIX_EFFECT(RAINBOW_BEACON)
#    ifdef RGB_MATRIX_CUSTOM_EFFECT_IMPLS

static void RAINBOW_BEACON_math(HSV* hsv, int8_t sin, int8_t cos, uint8_t i, uint8_t time) { hsv->h = ((g_led_config.point[i].y - k_rgb_matrix_center.y) * 2 * cos + (g_led_config.point[i].x - k_rgb_matrix_center.x) * 2 * sin) / 128 + rgb_matrix_config.hue; }

bool RAINBOW_BEACON(effect_params_t* params) { return effect_runner_sin_cos_i(params, &RAINBOW_BEACON_math); }

#    endif  // RGB_MATRIX_CUSTOM_EFFECT_IMPLS
#endif      // DISABLE_RGB_MATRIX_RAINBOW_BEACON