QMK/keyboards/betalupi_ergodox/animations/fft.h

#ifdef RGB_MATRIX_FRAMEBUFFER_EFFECTS
#ifndef DISABLE_RGB_MATRIX_FFT_ANIM
RGB_MATRIX_EFFECT(FFT_ANIM)

#ifdef RGB_MATRIX_CUSTOM_EFFECT_IMPLS

#include "extra_mappings.h"

// TODO:
// Dynamic color settings
bool FFT_ANIM(effect_params_t* params) {
	uint8_t led_min = RGB_MATRIX_LED_PROCESS_LIMIT * params->iter;
	uint8_t led_max = led_min + RGB_MATRIX_LED_PROCESS_LIMIT;
	if (led_max > sizeof(g_rgb_frame_buffer)) led_max = sizeof(g_rgb_frame_buffer);

	if (params->init) {
		rgb_matrix_set_color_all(0, 0, 0);
		memset(g_rgb_frame_buffer, 0, sizeof g_rgb_frame_buffer);
	}


	// Render heatmap & decrease
	for (int i = led_min; i < led_max; i++) {
		uint8_t row = i % MATRIX_ROWS;
		uint8_t col = i / MATRIX_ROWS;
		uint8_t val = g_rgb_frame_buffer[row][col];

		bool is_topmost = false;
		int8_t height = fft_array_to_col[col][row] % 5;
		int8_t bin = fft_array_to_col[col][row] / 5;
		if (height == 5 - 1) {
			is_topmost = true;
		} else {
			// Row and col of key above this one
			if (
				g_rgb_frame_buffer[
					fft_col_to_array[bin][height + 1] % MATRIX_ROWS
				][
					fft_col_to_array[bin][height + 1] / MATRIX_ROWS
				] == 0
			) {
				is_topmost = true;
			}
		}

		if (is_topmost) {
			rgb_matrix_set_color(i, val, 0x00, val);
		} else {
			rgb_matrix_set_color(i, 0x00, 0x00, val);
		}
	}

	return led_max < sizeof(g_rgb_frame_buffer);
}

#endif
#endif
#endif