pixie_chroma_internal.cpp

/*!
 * @file pixie_chroma_internal.cpp
 *
 * Designed specifically to work with Pixie Chroma:
 * ----> https://connornishijima.github.io/PixieChroma
 *
 * Last Updated by Connor Nishijima on 10/21/21
 */

#include "Pixie_Chroma.h" 
#include "utility/pixie_utility.h"


// ---------------------------------------------------------------------------------------------------------|
// -- PUBLIC CLASS FUNCTIONS -------------------------------------------------------------------------------|
// ---------------------------------------------------------------------------------------------------------|


/**************************************************************************/
/*!
    @brief  Used to initialize the PixieChroma library. Example usage before
            setup() would be:
	
                #include "Pixie_Chroma.h"
                PixieChroma pix;
	
            NOTE: Due to current limitations with the library, your class
            instance MUST be named "pix". Mutiple instances are not yet
            possible. Because each of these functions are contained in the
            PixieChroma class object, you'll use them like this:
	
                pix.print("Hello!");
	
*/
/**************************************************************************/
PixieChroma::PixieChroma(){}


/**************************************************************************/
/*!
	@brief  Initializes the display buffer, populates the XY coordinate
			table, defaults the display colors to green, loads the default
			CRGBPalette, initializes FastLED, sets the default power budget,
			and kicks off the animation ISR.
            
            Pixie Chroma allows for multi-row displays, which are wired in
            reading order (left to right, top to bottom) and their shape is
            define here. For example, a 16-Pixie display with two rows of eight:
            
                data_pin
			       |
                +--+-+   +----+   +----+   +----+   +----+   +----+   +----+   +----+
                |  1 |-->|  2 |-->|  3 |-->|  4 |-->|  5 |-->|  6 |-->|  7 |-->|  8 | 
                +----+   +----+   +----+   +----+   +----+   +----+   +----+   +--+-+
                                                                                  |
                   +--------------------------------------------------------------+
                   |
                +--+-+   +----+   +----+   +----+   +----+   +----+   +----+   +----+
                |  9 |-->| 10 |-->| 11 |-->| 12 |-->| 13 |-->| 14 |-->| 15 |-->| 16 | 
                +----+   +----+   +----+   +----+   +----+   +----+   +----+   +----+
            
            The corresponding setup for this display layout would be:
            
                #include "Pixie_Chroma.h"
                PixieChroma pix;

                #define DATA_PIN 5
                #define PIXIES_X 8
                #define PIXIES_Y 2

                void setup() {
                    pix.begin(DATA_PIN, PIXIES_X, PIXIES_Y);
                }
            
            For faster performance on large displays, see begin_quad().
	
	@param  data_pin GPIO pin to use for FastLED output
	@param  pixies_x Number of Pixie PCBs in the X axis of your display
	@param  pixies_y Number of Pixie PCBs in the Y axis of your display
*/
/**************************************************************************/
void PixieChroma::begin(const uint8_t data_pin, uint8_t pixies_x, uint8_t pixies_y){
	pixie_pin = data_pin;

	chars_x = pixies_x*2; // Pixies have two chars each
	chars_y = pixies_y;

	matrix_width  = display_width*chars_x;
	matrix_height = display_height*chars_y;

	NUM_LEDS = (matrix_width*matrix_height);

	leds = new CRGB[NUM_LEDS+1]; // Hidden extra LED to write to if we call an out-of-bounds XY coordinate for color or mask
	mask = new uint8_t[NUM_LEDS+1];
	xy_table = new int16_t[NUM_LEDS];

	calc_xy();

	mask_out = new uint8_t[NUM_VISIBLE_LEDS];
	leds_out = new CRGB[NUM_VISIBLE_LEDS];

	for(uint16_t i = 0; i < NUM_VISIBLE_LEDS; i++){
		leds[i] = CRGB(0,255,0);
	}

	current_palette.loadDynamicGradientPalette(GREEN_SOLID);

	build_controller(pixie_pin); // ------ Initialize FastLED
	set_animation(ANIMATION_NULL); // ---- Set animation function to an empty one
	clear(); // -------------------------- Clear anything in mask (should be empty anyways), reset cursor
	set_max_power(5.0, 500); // ---------- Set default power budget in volts and milliamps
}


/**************************************************************************/
/*!
	@brief  Initializes the display buffer, populates the XY coordinate
			table, defaults the display colors to green, loads the default
			CRGBPalette, initializes FastLED, sets the default power budget,
			and kicks off the animation ISR.
        
            This version of begin() is special, in that it will send your
            image data to the LEDs in 4 parallel streams to increase speed.
            
            Unfortunately, this requires hard-coded pins on the ESP8266 to
            function *due to FastLED limitations*:
            
            - DATA_OUT_1:  **GPIO 12 / D6**
            - DATA_OUT_2:  **GPIO 13 / D7**
            - DATA_OUT_3:  **GPIO 14 / D5**
            - DATA_OUT_4:  **GPIO 15 / D8**
            
            On each data line, you'll wire `pixies_per_pin` number of Pixie
            Chromas, with the final image being seamlessly spread across these
            four lines.
            
            For example, if you have 16 Pixie Chromas (in two rows of eight) and
            have Quad Mode enabled, then each of the 4 data lines will have 4
            Pixie Chromas like so:
            
            - **DATA_OUT_1** GPIO
                - Pixie 1
                - Pixie 2
                - Pixie 3
                - Pixie 4
            - **DATA_OUT_2** GPIO
                - Pixie 5
                - Pixie 6
                - Pixie 7
                - Pixie 8
            - **DATA_OUT_3** GPIO
                - Pixie 9
                - Pixie 10
                - Pixie 11
                - Pixie 12
            - **DATA_OUT_4** GPIO
                - Pixie 13
                - Pixie 14
                - Pixie 15
                - Pixie 16
            
            The corresponding setup for this display layout would be:
            
                #include "Pixie_Chroma.h"
                PixieChroma pix;

                #define PIXIES_PER_PIN 4
                #define PIXIES_X       8
                #define PIXIES_Y       2

                void setup() {
                    pix.begin_quad(PIXIES_PER_PIN, PIXIES_X, PIXIES_Y);
                }
                
            Then, with the displays physically arranged in reading order (left to right,
            top to bottom) you're ready to begin!
            
                                         
                PIN 1 -------+                       PIN 2 ---------+
                             |                                      |
                          +--+-+   +----+   +----+   +----+  ||  +--+-+   +----+   +----+   +----+
                          |  1 |-->|  2 |-->|  3 |-->|  4 |  ||  |  5 |-->|  6 |-->|  7 |-->|  8 | 
                          +----+   +----+   +----+   +----+  ||  +----+   +----+   +----+   +----+ 

                PIN 3 -------+                       PIN 4 ---------+
                             |                                      |
                          +--+-+   +----+   +----+   +----+  ||  +--+-+   +----+   +----+   +----+
                          |  9 |-->| 10 |-->| 11 |-->| 12 |  ||  | 13 |-->| 14 |-->| 15 |-->| 16 | 
                          +----+   +----+   +----+   +----+  ||  +----+   +----+   +----+   +----+ 
                
            Using begin_quad() to enable the Quad Mode driver will
            always send the 4 lines of data in parallel, saving on time per frame.
            
            begin_quad() ideally **should not be used with less than 4 Pixie Chromas**,
            with at least one on each line. Even if only two lines are used, all 4 pins are
            still occupied by Quad Mode.
	
	@param  pixies_per_pin  Pixies per data pin
	@param  pixies_x        Number of Pixie PCBs in the X axis of your display
	@param  pixies_y        Number of Pixie PCBs in the Y axis of your display
*/
/**************************************************************************/
void PixieChroma::begin_quad(uint8_t pixies_per_pin, uint8_t pixies_x, uint8_t pixies_y){	
	chars_x = pixies_x*2; // Pixies have two chars each
	chars_y = pixies_y;

	matrix_width  = display_width*chars_x;
	matrix_height = display_height*chars_y;

	NUM_LEDS = (matrix_width*matrix_height);

	leds = new CRGB[NUM_LEDS+1]; // Hidden extra LED to write to if we call an out-of-bounds XY coordinate for color or mask
	mask = new uint8_t[NUM_LEDS+1];
	xy_table = new int16_t[NUM_LEDS];

	calc_xy();

	mask_out = new uint8_t[NUM_VISIBLE_LEDS];
	leds_out = new CRGB[NUM_VISIBLE_LEDS];

	for(uint16_t i = 0; i < NUM_VISIBLE_LEDS; i++){
		leds[i] = CRGB(0,255,0);
	}

	current_palette.loadDynamicGradientPalette(GREEN_SOLID);

    // WS2811_PORTA on ESP8266 takes up GPIO 12, GPIO 13, GPIO 14 and GPIO 15 for Quad Mode
	FastLED.addLeds<WS2811_PORTA,4>(leds_out, pixies_per_pin*70).setCorrection(TypicalLEDStrip); // Initialize FastLED
    
	set_animation(ANIMATION_NULL); // ---- Set animation function to an empty one
	clear(); // -------------------------- Clear anything in mask (should be empty anyways), reset cursor
	set_max_power(5, 500); // ------------ Set default power budget in volts and milliamps
}


/**************************************************************************/
/*!
    @brief  Takes an 8-bit brightness value and passes it to FastLED
            internally, to provide global brightness control with temporal
            dithering
	
    @param  level 8-bit global brightness value (0-255)
*/
/**************************************************************************/
void PixieChroma::set_brightness(uint8_t level){
	brightness_level = level;
}


/**************************************************************************/
/*!
    @brief  Accepts a const uint8_t (8-bit) array with the following format
            to generate a FastLED Gradient Palette at runtime:

                const uint8_t* my_gradient_palette[] = {
                    [INDEX],  [R_VAL],  [G_VAL],  [B_VAL],
                    0,      255,    0,      0, 
                    127,    0,      255,    0, 
                    255,    0,      0,      255, 
                };

            On each line is the index of the color (0-255) to express the
            position in the gradient this color occurs. So in the given
            example, it is a gradient from red at 0, to green at 127, to
            blue at 255.
				
    @param  pal FastLED "Gradient Palette" array
*/
/**************************************************************************/
void PixieChroma::set_palette(const uint8_t* pal){ // GRADIENT PALETTE
	current_palette.loadDynamicGradientPalette(pal);
}


/**************************************************************************/
/*!
    @brief  Accepts a FastLED CRGBPalette16 object to set the current color
            palette for animation
	
    @param  pal FastLED CRGBPalette16 object to use
*/
/**************************************************************************/
void PixieChroma::set_palette(CRGBPalette16 pal){ // STANDARD PALETTE
	current_palette = pal;
}


/**************************************************************************/
/*!
    @brief	Accepts a preset or custom function to use for the animation ISR.
            For a list of predefined animations, see pixie_animations.h

    @param  action Function to set as an animation ISR
*/
/**************************************************************************/
void PixieChroma::set_animation(void (*action)(float)) {
	anim_func = action;
}


/**************************************************************************/
/*!
    @brief  Used to scale the animation speed of animation ISRs that can use
            pix.animation_speed to scale their speeds or for other effects
				
    @param  speed Floating point value: 1.0 = 100%, 3.2 = 320%, 0.5 = 50%
*/
/**************************************************************************/
void PixieChroma::set_animation_speed(float speed){
	animation_speed = speed;
}


/**************************************************************************/
/*!
    @brief  Allows you to enable built-in automatic gamma correction, using
            a fast LUT in pixie_utility.h. (Not enabled by default)

    @param  enabled Whether or not to apply gamma correction
*/
/**************************************************************************/
void PixieChroma::set_gamma_correction(bool enabled){
	correct_gamma = enabled;
}


/**************************************************************************/
/*!
    @brief  Sets the cursor position in a 2D context, in whole displays.
            Wherever the cursor is, is where the next call to print() or
            write() will originate. Position is counted from zero. Remember:
            each Pixie Chroma has two "displays" on it.

                +-----------------+   +-----------------+   +-----------------+
                |      + + +      |   |      + + +      |   |      + + +      |
                |+-----+   +-----+|   |+-----+   +-----+|   |+-----+   +-----+|
                ||     |   |     ||   ||     |   |     ||   ||     |   |     ||
                ||     |   |     ||   ||     |   |     ||   ||     |   |     ||
                || 0,0 |   | 1,0 ||-->|| 2,0 |   | 3,0 ||-->|| 4,0 |   | 5,0 ||
                ||     |   |     ||   ||     |   |     ||   ||     |   |     ||
                ||     |   |     ||   ||     |   |     ||   ||     |   |     ||
                |+-----+   +-----+|   |+-----+   +-----+|   |+-----+   +-----+|
                |      + + +      |   |      + + +      |   |      + + +      |
                +-----------------+   +-----------------+   +-----------------+
                                                                   |
                       +-------------------------------------------+
                       |
                       V
                +-----------------+   +-----------------+   +-----------------+
                |      + + +      |   |      + + +      |   |      + + +      |
                |+-----+   +-----+|   |+-----+   +-----+|   |+-----+   +-----+|
                ||     |   |     ||   ||     |   |     ||   ||     |   |     ||
                ||     |   |     ||   ||     |   |     ||   ||     |   |     ||
                || 0,1 |   | 1,1 ||-->|| 2,1 |   | 3,1 ||-->|| 4,0 |   | 5,1 ||
                ||     |   |     ||   ||     |   |     ||   ||     |   |     ||
                ||     |   |     ||   ||     |   |     ||   ||     |   |     ||
                |+-----+   +-----+|   |+-----+   +-----+|   |+-----+   +-----+|
                |      + + +      |   |      + + +      |   |      + + +      |
                +-----------------+   +-----------------+   +-----------------+

            For example:

                set_cursor(1,0) // Sets the cursor to the second display in the first row

                set_cursor(3,1) // Sets the cursor to the fourth display in the second row

    @param  x_position New cursor position on the X-axis, in whole displays
    @param  y_position New cursor position on the Y-axis, in whole displays
*/
/**************************************************************************/
void PixieChroma::set_cursor(uint8_t x_position, uint8_t y_position){
	cursor_x = (display_width*x_position)+1;
	cursor_y = (display_height*y_position)+2;
}


/**************************************************************************/
/*!
    @brief  Sets the maximum power budget in volts and milliamps. Knowing
            the average power consumption of these LEDs at any given color,
            FastLED will automatically globally scale down the output values
            with temporal dithering to lower power usage until it is within
            the budget defined here. Defaults to 5.0V / 500mA to protect PC
			USB ports if the LEDs are not independently powered.
			(2000mA = 2A, 500mA = 0.5A, etc.)

    @param  volts Total LED power budget in volts. (default: 5.0)
    @param  milliamps Total LED power budget in milliamps (default 500)
*/
/**************************************************************************/
void PixieChroma::set_max_power(float volts, uint16_t milliamps){
	max_V = volts;
	max_mA = milliamps;
}


/**************************************************************************/
/*!
    @brief  Writes an icon* to a specified X and Y cursor position
	
    @param  icon   The icon to write
    @param  x_pos  X cursor position of write **[optional]**
    @param  y_pos  Y cursor position of write **[optional]**
*/
/**************************************************************************/
void PixieChroma::write(const uint8_t* icon, uint8_t x_pos, uint8_t y_pos){
	uint16_t x_start = 1;
	uint16_t y_start = 2;
	write_pix(icon, x_start+(display_width*x_pos), y_start+(display_height*y_pos));
}


/**************************************************************************/
/*!
    @brief  Writes an icon to a specified X and Y cursor position, taking
            five uint8_t as input for the column data.
	   
            For example:
            
                pix.write(B00101111, B01001001, B01001001, B01001001, B00110001);
                
                    OR, WRITTEN VERTICALLY:
                
                pix.write(   ,   ,   ,   ,   );
                           1   1   1   1   1  LSB
		                   1   0   0   0   0
		                   1   0   0   0   0
		                   1   1   1   1   0
		                   0   0   0   0   1
		                   1   0   0   0   1
		                   0   1   1   1   0  
                           0   0   0   0   0  MSB (unused)
                           B   B   B   B   B

            This writes a "5" to the display, seen above in the "1" bits of
            each column. The MSB (highest bit) is not used in icons.
	
    @param  icon_col_1  Column 1 data of this icon
    @param  icon_col_2  Column 2 data of this icon
    @param  icon_col_3  Column 3 data of this icon
    @param  icon_col_4  Column 4 data of this icon
    @param  icon_col_5  Column 5 data of this icon
    @param  x_pos       X cursor position of write **[optional]**
    @param  y_pos       Y cursor position of write **[optional]**
*/
/**************************************************************************/
void PixieChroma::write(uint8_t icon_col_1, uint8_t icon_col_2, uint8_t icon_col_3, uint8_t icon_col_4, uint8_t icon_col_5, uint8_t x_pos, uint8_t y_pos){
	uint8_t icon[5] = {icon_col_1,icon_col_2,icon_col_3,icon_col_4,icon_col_5};
	write(icon, x_pos, y_pos);
}


/**************************************************************************/
/*!
    @brief  Writes a char* string to a specified X and Y cursor position
	
    @param  message  char* string to write
    @param  x_pos    X cursor position of write **[optional]**
    @param  y_pos    Y cursor position of write **[optional]**
*/
/**************************************************************************/
void PixieChroma::write(char* message, uint8_t x_pos, uint8_t y_pos){
	uint16_t x_start = 1;
	uint16_t y_start = 2;
	write_pix(message, x_start+(display_width*x_pos), y_start+(display_height*y_pos));
}


/**************************************************************************/
/*!
    @brief  Writes a signed 16-bit integer to a specified X and Y
            cursor position
	
    @param  input    Signed integer to write
    @param  x_pos    X cursor position of write **[optional]**
    @param  y_pos    Y cursor position of write **[optional]**
*/
/**************************************************************************/
void PixieChroma::write(int16_t input, uint8_t x_pos, uint8_t y_pos){
	uint16_t x_start = 1;
	uint16_t y_start = 2;

	char char_buf[32];
	itoa(input,char_buf,10);

	write_pix(char_buf, x_start+(display_width*x_pos), y_start+(display_height*y_pos));
}


/**************************************************************************/
/*!
    @brief  Writes an unsigned 16-bit integer to a specified X and Y
            cursor position
	
    @param  input    Unsigned integer to write
    @param  x_pos    X cursor position of write **[optional]**
    @param  y_pos    Y cursor position of write **[optional]**
*/
/**************************************************************************/
void PixieChroma::write(uint16_t input, uint8_t x_pos, uint8_t y_pos){
	uint16_t x_start = 1;
	uint16_t y_start = 2;

	char char_buf[32];
	utoa(input,char_buf,10);

	write_pix(char_buf, x_start+(display_width*x_pos), y_start+(display_height*y_pos));
}


/**************************************************************************/
/*!
    @brief  Writes a signed 32-bit integer to a specified X and Y
            cursor position
	
    @param  input    Signed integer to write
    @param  x_pos    X cursor position of write **[optional]**
    @param  y_pos    Y cursor position of write **[optional]**
*/
/**************************************************************************/
void PixieChroma::write(int32_t input, uint8_t x_pos, uint8_t y_pos){
	uint16_t x_start = 1;
	uint16_t y_start = 2;

	char char_buf[32];
	ltoa(input,char_buf,10);

	write_pix(char_buf, x_start+(display_width*x_pos), y_start+(display_height*y_pos));
}


/**************************************************************************/
/*!
    @brief  Writes an unsigned 32-bit integer to a specified X and Y
            cursor position
	
    @param  input    Unsigned integer to write
    @param  x_pos    X cursor position of write **[optional]**
    @param  y_pos    Y cursor position of write **[optional]**
*/
/**************************************************************************/
void PixieChroma::write(uint32_t input, uint8_t x_pos, uint8_t y_pos){
	uint16_t x_start = 1;
	uint16_t y_start = 2;

	char char_buf[32];
	ultoa(input,char_buf,10);

	write_pix(char_buf, x_start+(display_width*x_pos), y_start+(display_height*y_pos));
}


#if defined(ESP8266) || defined(ESP32)
/**************************************************************************/
/*!
    @brief  Writes an unsigned 32-bit integer to a specified X and Y
            cursor position (Stupid ESP-specific type)
	
    @param  input    Unsigned integer to write
    @param  x_pos    X cursor position of write **[optional]**
    @param  y_pos    Y cursor position of write **[optional]**
*/
/**************************************************************************/
void PixieChroma::write(long unsigned int input, uint8_t x_pos, uint8_t y_pos){
    uint16_t x_start = 1;
	uint16_t y_start = 2;

	char char_buf[32];
	ultoa(input,char_buf,10);

	write_pix(char_buf, x_start+(display_width*x_pos), y_start+(display_height*y_pos));
}
#endif


/**************************************************************************/
/*!
    @brief  Writes a double-precision floating point value to a specified
            X and Y cursor position, to a specified number of decimal places
	
    @param  input    Double-precision float to write
    @param  places   Number of decimal places to show **[optional]**
    @param  x_pos    X cursor position of write **[optional]**
    @param  y_pos    Y cursor position of write **[optional]**
*/
/**************************************************************************/
void PixieChroma::write(double input, uint8_t places, uint8_t x_pos, uint8_t y_pos){
	uint16_t x_start = 1;
	uint16_t y_start = 2;

	char char_buf[32];
	dtoa(input,char_buf,places);

	write_pix(char_buf, x_start+(display_width*x_pos), y_start+(display_height*y_pos));
}


/**************************************************************************/
/*!
    @brief  Writes a single-precision floating point value to a specified
            X and Y cursor position, to a specified number of decimal places
	
    @param  input    Single-precision float to write
    @param  places   Number of decimal places to show **[optional]**
    @param  x_pos    X cursor position of write **[optional]**
    @param  y_pos    Y cursor position of write **[optional]**
*/
/**************************************************************************/
void PixieChroma::write(float input, uint8_t places, uint8_t x_pos, uint8_t y_pos){
	write(double(input), places, x_pos, y_pos);
}



/**************************************************************************/
/*!
    @brief  Internal function for rendering icons to the mask buffer.
            This can also be used to write Icons that are not aligned to
            whole display positions, such as during smooth scrolling.
	
    @param  icon     Icon to render
    @param  x_pos    X pixel position of write **[optional]**
    @param  y_pos    Y pixel position of write **[optional]**
*/
/**************************************************************************/
void PixieChroma::write_pix(const uint8_t* icon, int16_t x_pos, int16_t y_pos){
	add_char(icon, cursor_x, cursor_y);
	cursor_x += display_width;
}


/**************************************************************************/
/*!
    @brief  Internal function for rendering char* strings to the mask
            buffer. All other write() function overloads eventually end up
            casted to char* strings and passed to this function for
            rendering. This can also be used to write char* strings that
            are not aligned to whole display positions, such as during
            smooth scrolling.
	
    @param  message  char* string to render
    @param  x_pos    X pixel position of write **[optional]**
    @param  y_pos    Y pixel position of write **[optional]**
*/
/**************************************************************************/
void PixieChroma::write_pix(char* message, int16_t x_pos, int16_t y_pos){
	uint8_t len = strlen(message);
	int16_t x_offset = x_pos;
	int16_t y_offset = y_pos;
	for(uint8_t i = 0; i < len; i++){
		if(message[i] == '\n'){
			y_offset += display_height;
			x_offset = 1;
			cursor_x = 1;
			cursor_y += display_height;
		}
		else if(message[i] == 0 || message[i] == '\0'){ // early end of string
			return;
		}
		else{
			add_char(message[i], cursor_x, cursor_y);
			x_offset += display_width;
			cursor_x += display_width;
		}		
	}
}


/**************************************************************************/
/*!
    @brief  Internal function for rendering a single char to the mask
            buffer. All other write() function overloads eventually end up
            casted to char* strings and passed to this function one
            character at a time for rendering.
	
    @param  chr      char to render
    @param  x_pos    X pixel position of write
    @param  y_pos    Y pixel position of write
*/
/**************************************************************************/
void PixieChroma::add_char(char chr, int16_t x_pos, int16_t y_pos){
	if (chr >= 32) {
		chr -= 32;
	}

	for(uint8_t x = 0; x < 5; x++){
		uint8_t column = pgm_read_byte(font+(chr * 5 + x));

		uint16_t row1_index = xy(x_pos+x, y_pos+0);
		uint16_t row2_index = xy(x_pos+x, y_pos+1);
		uint16_t row3_index = xy(x_pos+x, y_pos+2);
		uint16_t row4_index = xy(x_pos+x, y_pos+3);
		uint16_t row5_index = xy(x_pos+x, y_pos+4);
		uint16_t row6_index = xy(x_pos+x, y_pos+5);
		uint16_t row7_index = xy(x_pos+x, y_pos+6);

		// "Subtract" from mask transparency with saturating function
		mask[row1_index] = qadd8( mask[row1_index],  bit_table[bitRead(column,0)] );
		mask[row2_index] = qadd8( mask[row2_index],  bit_table[bitRead(column,1)] );
		mask[row3_index] = qadd8( mask[row3_index],  bit_table[bitRead(column,2)] );
		mask[row4_index] = qadd8( mask[row4_index],  bit_table[bitRead(column,3)] );
		mask[row5_index] = qadd8( mask[row5_index],  bit_table[bitRead(column,4)] );
		mask[row6_index] = qadd8( mask[row6_index],  bit_table[bitRead(column,5)] );
		mask[row7_index] = qadd8( mask[row7_index],  bit_table[bitRead(column,6)] );
	}
}


/**************************************************************************/
/*!
    @brief  Internal function for rendering a single icon to the mask
            buffer. All other write() function overloads eventually end up
            casted to char* strings and passed to this function one
            character at a time for rendering.
	
    @param  icon     Icon column data to render
    @param  x_pos    X pixel position of write
    @param  y_pos    Y pixel position of write
*/
/**************************************************************************/
void PixieChroma::add_char(const uint8_t* icon, int16_t x_pos, int16_t y_pos){
	for(uint8_t x = 0; x < 5; x++){
		uint8_t column = pgm_read_byte_far(icon+x);

		uint16_t row1_index = xy(x_pos+x, y_pos+0);
		uint16_t row2_index = xy(x_pos+x, y_pos+1);
		uint16_t row3_index = xy(x_pos+x, y_pos+2);
		uint16_t row4_index = xy(x_pos+x, y_pos+3);
		uint16_t row5_index = xy(x_pos+x, y_pos+4);
		uint16_t row6_index = xy(x_pos+x, y_pos+5);
		uint16_t row7_index = xy(x_pos+x, y_pos+6);

		// "Subtract" from mask transparency with saturating function
		mask[row1_index] = qadd8( mask[row1_index],  bit_table[bitRead(column,0)] );
		mask[row2_index] = qadd8( mask[row2_index],  bit_table[bitRead(column,1)] );
		mask[row3_index] = qadd8( mask[row3_index],  bit_table[bitRead(column,2)] );
		mask[row4_index] = qadd8( mask[row4_index],  bit_table[bitRead(column,3)] );
		mask[row5_index] = qadd8( mask[row5_index],  bit_table[bitRead(column,4)] );
		mask[row6_index] = qadd8( mask[row6_index],  bit_table[bitRead(column,5)] );
		mask[row7_index] = qadd8( mask[row7_index],  bit_table[bitRead(column,6)] );
	}
}


/**************************************************************************/
/*!
    @brief  Prints an Icon to the displays, at the current cursor position.
	
    @param  icon     Icon column data to render
*/
/**************************************************************************/
void PixieChroma::print(const uint8_t* icon){
	write_pix(icon, cursor_x, cursor_y);
}


/**************************************************************************/
/*!
    @brief  Prints an icon to the displays at the current cursor position,
            taking five uint8_t as input for the column data.
	   
            For example:
            
                pix.print(B00101111, B01001001, B01001001, B01001001, B00110001);
                
                    OR, WRITTEN VERTICALLY:
                
                pix.print(   ,   ,   ,   ,   );
                           1   1   1   1   1  LSB
		                   1   0   0   0   0
		                   1   0   0   0   0
		                   1   1   1   1   0
		                   0   0   0   0   1
		                   1   0   0   0   1
		                   0   1   1   1   0  
                           0   0   0   0   0  MSB (unused)
                           B   B   B   B   B

            This writes a "5" to the display, seen above in the "1" bits of
            each column. The MSB (highest bit) is not used in icons.
	
    @param  icon_col_1  Column 1 data of this icon
    @param  icon_col_2  Column 2 data of this icon
    @param  icon_col_3  Column 3 data of this icon
    @param  icon_col_4  Column 4 data of this icon
    @param  icon_col_5  Column 5 data of this icon
*/
/**************************************************************************/
void PixieChroma::print(uint8_t icon_col_1, uint8_t icon_col_2, uint8_t icon_col_3, uint8_t icon_col_4, uint8_t icon_col_5){
	const uint8_t icon[5] = {
		icon_col_1,
		icon_col_2,
		icon_col_3,
		icon_col_4,
		icon_col_5,
	};
	write_pix(icon, cursor_x, cursor_y);
}


/**************************************************************************/
/*!
    @brief  Prints a char* string to the displays at the current cursor
            position
	
    @param  message  char* string to print
*/
/**************************************************************************/
void PixieChroma::print(char* message){
	write_pix(message, cursor_x, cursor_y);
}


/**************************************************************************/
/*!
    @brief  Prints a signed 16-bit integer to the displays at the current
            cursor position
	
    @param  input  Signed integer to print
*/
/**************************************************************************/
void PixieChroma::print(int16_t input){
	char char_buf[32];
	itoa(input,char_buf,10);
	write_pix(char_buf, cursor_x, cursor_y);
}


/**************************************************************************/
/*!
    @brief  Prints an unsigned 16-bit integer to the displays at the current
            cursor position
	
    @param  input  Unsigned integer to print
*/
/**************************************************************************/
void PixieChroma::print(uint16_t input){
	char char_buf[32];
	utoa(input,char_buf,10);
	write_pix(char_buf, cursor_x, cursor_y);
}


/**************************************************************************/
/*!
    @brief  Prints a signed 32-bit integer to the displays at the current
            cursor position
	
    @param  input  Signed integer to print
*/
/**************************************************************************/
void PixieChroma::print(int32_t input){
	char char_buf[32];
	ltoa(input,char_buf,10);
	write_pix(char_buf, cursor_x, cursor_y);
}


/**************************************************************************/
/*!
    @brief  Prints an unsigned 32-bit integer to the displays at the current
            cursor position
	
    @param  input  Unsigned integer to print
*/
/**************************************************************************/
void PixieChroma::print(uint32_t input){
	char char_buf[32];
	ultoa(input,char_buf,10);
	write_pix(char_buf, cursor_x, cursor_y);
}


#if defined(ESP8266) || defined(ESP32)
/**************************************************************************/
/*!
    @brief  Prints an unsigned 32-bit integer to the displays at the current
            cursor position. (Dumb ESP-specific type)
	
    @param  input  Unsigned integer to print
*/
/**************************************************************************/
void PixieChroma::print(long unsigned int input){
	char char_buf[32];
	ultoa(input,char_buf,10);
	write_pix(char_buf, cursor_x, cursor_y);
}
#endif


/**************************************************************************/
/*!
    @brief  Prints a double-precision floating point integer to the displays
            at the current cursor position, to a specified number of decimal
            places.
	
    @param  input   double to print
    @param  places  Number of decimal places to print **[optional]**
*/
/**************************************************************************/
void PixieChroma::print(double input, uint8_t places){
	char char_buf[32];
	dtoa(input,char_buf,places);
	write_pix(char_buf, cursor_x, cursor_y);
}


/**************************************************************************/
/*!
    @brief  Prints a single-precision floating point integer to the displays
            at the current cursor position, to a specified number of decimal
            places.
	
    @param  input   float to print
    @param  places  Number of decimal places to print **[optional]**
*/
/**************************************************************************/
void PixieChroma::print(float input, uint8_t places){
	print(double(input), places);
}


/**************************************************************************/
/*!
    @brief  Prints an Icon to the displays at the current cursor position,
            then jumps to the next row in the Pixie display, similar to a
            newline '\\n' character.
    
    @param  icon     Icon column data to print
*/
/**************************************************************************/
void PixieChroma::println(const uint8_t* icon){
	write_pix(icon, cursor_x, cursor_y); // ........ Output
	cursor_x = 1;
	cursor_y += display_height;
}


/**************************************************************************/
/*!
    @brief  Prints an Icon to the displays at the current cursor position,
            (taking five uint8_t as input for the column data) then jumps
            to the next row in the Pixie display, similar to a newline
            '\\n' character.
    
    @param  icon_col_1  Column 1 data of this icon
    @param  icon_col_2  Column 2 data of this icon
    @param  icon_col_3  Column 3 data of this icon
    @param  icon_col_4  Column 4 data of this icon
    @param  icon_col_5  Column 5 data of this icon
*/
/**************************************************************************/
void PixieChroma::println(uint8_t icon_col_1, uint8_t icon_col_2, uint8_t icon_col_3, uint8_t icon_col_4, uint8_t icon_col_5){
	const uint8_t icon[5] = {
		icon_col_1,
		icon_col_2,
		icon_col_3,
		icon_col_4,
		icon_col_5,
	};
	write_pix(icon, cursor_x, cursor_y);
	cursor_x = 1;
	cursor_y += display_height;
}


/**************************************************************************/
/*!
    @brief  Prints a char* string to the displays at the current cursor
            position, then jumps to the next row in the Pixie display,
            similar to a newline '\\n' character.
	
    @param  message  char* string to print
*/
/**************************************************************************/
void PixieChroma::println(char* message){
	write_pix(message, cursor_x, cursor_y); // ........ Output
	cursor_x = 1;
	cursor_y += display_height;
}


/**************************************************************************/
/*!
    @brief  Prints a signed 16-bit integer to the displays at the current
            cursor position, then jumps to the next row in the Pixie display,
            similar to a newline '\\n' character.
	
    @param  input  Signed 16-bit integer to print
*/
/**************************************************************************/
void PixieChroma::println(int16_t input){
	char char_buf[32];
	itoa(input,char_buf,10);
	println(char_buf);
}


/**************************************************************************/
/*!
    @brief  Prints an unsigned 16-bit integer to the displays at the current
            cursor position, then jumps to the next row in the Pixie display,
            similar to a newline '\\n' character.
	
    @param  input  Unsigned 16-bit integer to print
*/
/**************************************************************************/
void PixieChroma::println(uint16_t input){
	char char_buf[32];
	utoa(input,char_buf,10);
	println(char_buf);
}


/**************************************************************************/
/*!
    @brief  Prints a signed 32-bit integer to the displays at the current
            cursor position, then jumps to the next row in the Pixie display,
            similar to a newline '\\n' character.
	
    @param  input  Signed 32-bit integer to print
*/
/**************************************************************************/
void PixieChroma::println(int32_t input){
	char char_buf[32];
	ltoa(input,char_buf,10);
	println(char_buf);
}


/**************************************************************************/
/*!
    @brief  Prints an unsigned 32-bit integer to the displays at the current
            cursor position, then jumps to the next row in the Pixie display,
            similar to a newline '\\n' character.
	
    @param  input  Unsigned 32-bit integer to print
*/
/**************************************************************************/
void PixieChroma::println(uint32_t input){
	char char_buf[32];
	ultoa(input,char_buf,10);
	println(char_buf);
}


#if defined(ESP8266) || defined(ESP32)
/**************************************************************************/
/*!
    @brief  Prints an unsigned 32-bit integer to the displays at the current
            cursor position, then jumps to the next row in the Pixie display,
            similar to a newline '\\n' character. (Stupid ESP-specific type)
	
    @param  input  Unsigned 32-bit integer to print
*/
/**************************************************************************/
void PixieChroma::println(long unsigned int input){
	char char_buf[32];
	ultoa(input,char_buf,10);
	println(char_buf);
}
#endif


/**************************************************************************/
/*!
    @brief  Prints a double-precision floating point integer to the displays
            at the current cursor position (to a specified number of decimal
            places), then jumps to the next row in the Pixie display,
            similar to a newline '\\n' character.
            
    @param  input   double to print
    @param  places  Number of decimal places to print **[optional]**
*/
/**************************************************************************/
void PixieChroma::println(double input, uint8_t places){
	char char_buf[32];
	dtoa(input,char_buf,places);
	println(char_buf);
}


/**************************************************************************/
/*!
    @brief  Prints a single-precision floating point integer to the displays
            at the current cursor position (to a specified number of decimal
            places), then jumps to the next row in the Pixie display,
            similar to a newline '\\n' character.
            
    @param  input   float to print
    @param  places  Number of decimal places to print **[optional]**
*/
/**************************************************************************/
void PixieChroma::println(float input, uint8_t places){
	println(double(input), places);
}


/**************************************************************************/
/*!
    @brief  Blurs the mask buffer in both axes by blur_amount.
            
    @param  blur_amount   Amount to blur
*/
/**************************************************************************/
void PixieChroma::blur(fract8 blur_amount){
	blur_x(blur_amount);
	blur_y(blur_amount);
}


/**************************************************************************/
/*!
    @brief  Blurs the mask buffer in the X axis by blur_amount.
            
    @param  blur_amount   Amount to blur
*/
/**************************************************************************/
void PixieChroma::blur_x(fract8 blur_amount){
	uint8_t keep = 255 - blur_amount;
    uint8_t seep = blur_amount >> 1;
    for( uint8_t row = 0; row < matrix_height; row++) {
        uint8_t carryover = 0;
        for( uint8_t i = 0; i < matrix_width; i++) {
            uint8_t cur = mask[xy(i,row)];
            uint8_t part = cur;
            part = scale8(part, seep);
            cur  = scale8(cur, keep);
            cur  = qadd8(cur,carryover);
            if(i){
				mask[xy(i-1,row)] = qadd8(mask[xy(i-1,row)],part);
			}
            mask[xy(i,row)] = cur;
            carryover = part;
        }
    }
}


/**************************************************************************/
/*!
    @brief  Blurs the mask buffer in the Y axis by blur_amount.
            
    @param  blur_amount   Amount to blur
*/
/**************************************************************************/
void PixieChroma::blur_y(fract8 blur_amount){
	// blur columns
    uint8_t keep = 255 - blur_amount;
    uint8_t seep = blur_amount >> 1;
    for( uint8_t col = 0; col < matrix_width; ++col) {
        uint8_t carryover = 0;
        for( uint8_t i = 0; i < matrix_height; ++i) {			
			uint8_t cur = mask[xy(col,i)];
            uint8_t part = cur;
            part = scale8(part, seep);
            cur  = scale8(cur, keep);
            cur  = qadd8(cur,carryover);
            if(i){
				mask[xy(col,i-1)] = qadd8(mask[xy(col,i-1)],part);
			}
            mask[xy(col,i)] = cur;
            carryover = part;
        }
    }
}


/**************************************************************************/
/*!
    @brief  Darkens the mask buffer by an 8-bit amount. Optionally resets
            the cursor position.
            
    @param  amount        8-bit amount to darken the mask
    @param  reset_cursor  Reset the cursor to 0,0 **[optional]**
*/
/**************************************************************************/
void PixieChroma::dim(uint8_t amount, bool reset_cursor){
	if(reset_cursor){
		set_cursor(0,0);
	}
	
	for(uint16_t i = 0; i < NUM_LEDS; i+=11){
		mask[i+0]  = scale8(mask[i+0],  255-amount);
		mask[i+1]  = scale8(mask[i+1],  255-amount);
		mask[i+2]  = scale8(mask[i+2],  255-amount);
		mask[i+3]  = scale8(mask[i+3],  255-amount);
		mask[i+4]  = scale8(mask[i+4],  255-amount);
		mask[i+5]  = scale8(mask[i+5],  255-amount);
		mask[i+6]  = scale8(mask[i+6],  255-amount);
		mask[i+7]  = scale8(mask[i+7],  255-amount);
		mask[i+8]  = scale8(mask[i+8],  255-amount);
		mask[i+9]  = scale8(mask[i+9],  255-amount);
		mask[i+10] = scale8(mask[i+10], 255-amount);
	}
}


/**************************************************************************/
/*!
    @brief  Blurs the color buffer in both axes by blur_amount.
            
    @param  blur_amount   Amount to blur
*/
/**************************************************************************/
void PixieChroma::color_blur(fract8 blur_amount){
	color_blur_x(blur_amount);
	color_blur_y(blur_amount);
}


/**************************************************************************/
/*!
    @brief  Blurs the color buffer in the X axis by blur_amount.
            
    @param  blur_amount   Amount to blur
*/
/**************************************************************************/
void PixieChroma::color_blur_x(fract8 blur_amount){
	uint8_t keep = 255 - blur_amount;
    uint8_t seep = blur_amount >> 1;
    for( uint8_t row = 0; row < matrix_height; row++) {
        uint8_t carryover = 0;
        for( uint8_t i = 0; i < matrix_width; i++) {
            CRGB cur = leds[xy(i,row)];
            CRGB part = cur;
            part.nscale8( seep);
            cur.nscale8( keep);
            cur += carryover;
            if( i) leds[xy(i-1,row)] += part;
            leds[xy(i,row)] = cur;
            carryover = part;
        }
    }
}


/**************************************************************************/
/*!
    @brief  Blurs the color buffer in the Y axis by blur_amount.
            
    @param  blur_amount   Amount to blur
*/
/**************************************************************************/
void PixieChroma::color_blur_y(fract8 blur_amount){
	// blur rows same as columns, for irregular matrix
    uint8_t keep = 255 - blur_amount;
    uint8_t seep = blur_amount >> 1;
    for( uint8_t row = 0; row < matrix_width; row++) {
        CRGB carryover = CRGB::Black;
        for( uint8_t i = 0; i < matrix_height; i++) {
            CRGB cur = leds[xy(i,row)];
            CRGB part = cur;
            part.nscale8( seep);
            cur.nscale8( keep);
            cur += carryover;
            if( i) leds[xy(i-1,row)] += part;
            leds[xy(i,row)] = cur;
            carryover = part;
        }
    }
}


/**************************************************************************/
/*!
    @brief  Darkens the color buffer by an 8-bit amount.
            
    @param  amount        8-bit amount to darken the mask
*/
/**************************************************************************/
void PixieChroma::color_dim(uint8_t amount){
	CRGBSet leds_temp(leds, NUM_LEDS);
	leds_temp.fadeToBlackBy(amount);
}


/**************************************************************************/
/*!
    @brief  Returns the cursor's X position
*/
/**************************************************************************/
uint8_t PixieChroma::get_cursor_x(){
	return cursor_x / chars_x;
}


/**************************************************************************/
/*!
    @brief  Returns the cursor's Y position
*/
/**************************************************************************/
uint8_t PixieChroma::get_cursor_y(){
	return cursor_y / chars_y;
}


/**************************************************************************/
/*!
    @brief  Returns the cursor's X position in exact pixel coordinates
*/
/**************************************************************************/
int16_t PixieChroma::get_cursor_x_exact(){
	return cursor_x;
}


/**************************************************************************/
/*!
    @brief  Returns the cursor's Y position in exact pixel coordinates
*/
/**************************************************************************/
int16_t PixieChroma::get_cursor_y_exact(){
	return cursor_y;
}


/**************************************************************************/
/*!
    @brief  Clears (blackens) the current mask buffer and resets the cursor
            to 0,0
*/
/**************************************************************************/
void PixieChroma::clear(){
	memset(mask, 0, NUM_LEDS);
	set_cursor(0,0);
}


/**************************************************************************/
/*!
    @brief  PixieChroma operates in a 2D context, but is run using 1D
            arrays. This function returns the 1D index of a given 2D
	    coordinate in the display matrix.
	    
	    Optionally, the result can be run through a wrapping function
	    that allows coordinates out of range to wrap around the the 
	    opposite side of the 2D matrix.
	    
	    If wrap is not enabled, any coordinates outside of the
	    display matrix will be parsed to a 1D index that is unused
	    and unseen.
	    
    @param   x     Signed 2D X coordinate
    @param   y     Signed 2D Y coordinate
    @param   wrap  Enable wrapping function **[optional]**
    @return  The 1D index of your 2D coordinate
*/
/**************************************************************************/
uint16_t PixieChroma::xy(int16_t x, int16_t y, bool wrap) {
	if(wrap){
		while(x < 0){
			x += matrix_width;
		}
		while(x >= matrix_width){
			x -= matrix_width;
		}
		while(y < 0){
			y += matrix_height;
		}
		while(y >= matrix_height){
			y -= matrix_height;
		}
	}
	else{
		if(x < 0){
			return NUM_LEDS; // If offscreen without wrap return last led in matrix
		}
		else if(x >= matrix_width){
			return NUM_LEDS; // If offscreen without wrap return last led in matrix
		}
		if(y < 0){
			return NUM_LEDS; // If offscreen without wrap return last led in matrix
		}
		else if(y >= matrix_height){
			return NUM_LEDS; // If offscreen without wrap return last led in matrix
		}
	}

	// done wrapping / culling, time for transformation
	return xy_table[ (y * matrix_width) + x ];
}


/**************************************************************************/
/*!
    @brief  Sets the entire color buffer to a CRGB value. For example:
                pix.color(CRGB(0,255,255));
	    This would set all displays to cyan, a mix of green and blue.
	    
    @param  col FastLED CRGB color
*/
/**************************************************************************/
void PixieChroma::color(CRGB col){
	fill_solid(leds, NUM_LEDS, col);
}


/**************************************************************************/
/*!
    @brief  Sets a specific display in the color buffer to a CRGB value.
            For example:
                pix.color(CRGB(0,255,255), 1, 0);
	    This would set the **second display of the first row** to cyan, a
	    mix of green and blue.
	    
    @param  col FastLED CRGB color
    @param  x   X coordinate of display
    @param  y   y coordinate of display
*/
/**************************************************************************/
void PixieChroma::color(CRGB col, uint8_t x, uint8_t y){
	int16_t x_pos = x*display_width+1;
	int16_t y_pos = y*display_height+2;
	
	for(uint8_t xi = 0; xi < 5; xi++){
		leds[xy(x_pos+xi, y_pos+0)] = col;
		leds[xy(x_pos+xi, y_pos+1)] = col;
		leds[xy(x_pos+xi, y_pos+2)] = col;
		leds[xy(x_pos+xi, y_pos+3)] = col;
		leds[xy(x_pos+xi, y_pos+4)] = col;
		leds[xy(x_pos+xi, y_pos+5)] = col;
		leds[xy(x_pos+xi, y_pos+6)] = col;
	}
}


/**************************************************************************/
/*!
    @brief  Sets a rectangular area in the color buffer to a CRGB value.
            For example:
                pix.color(CRGB(0,255,255), 0, 0, 5, 5);
	    This would set **the first five columns and rows** of the color
	    buffer to cyan, a mix of green and blue.
	    
    @param  col FastLED CRGB color
    @param  x1  Starting X coordinate of the rectangle
    @param  y1  Starting Y coordinate of the rectangle
    @param  x2  Ending X coordinate of the rectangle (inclusive)
    @param  y2  Ending Y coordinate of the rectangle (inclusive)
*/
/**************************************************************************/
void PixieChroma::color(CRGB col, uint8_t x1, uint8_t y1, uint8_t x2, uint8_t y2){
	if(x2 < x1 || y2 < y1){
		return;
	}

	// Make rectangle selection inclusive
	x2+=1;
	y2+=1;
	
	int16_t x1_pos = x1*display_width+1;
	int16_t y1_pos = y1*display_height+2;
	
	int16_t x2_pos = x2*display_width+1;
	int16_t y2_pos = y2*display_height+2;

	uint16_t x_delta = x2_pos-x1_pos;
	uint16_t y_delta = y2_pos-y1_pos;
	
	for(uint16_t y = 0; y < y_delta; y++){
		for(uint16_t x = 0; x < x_delta; x++){
			int16_t x2_pos = x1_pos+x;
			int16_t y2_pos = y1_pos+y;
			leds[xy(x2_pos, y2_pos)] = col;
		}
	}
}


/**************************************************************************/
/*!
    @brief  Draws a line in the mask buffer using Bresenham's line algorithm
	    
    @param  x1  Starting X coordinate of the line
    @param  y1  Starting Y coordinate of the line
    @param  x2  Ending X coordinate of the line (inclusive)
    @param  y2  Ending Y coordinate of the line (inclusive)
*/
/**************************************************************************/
void PixieChroma::draw_line(int16_t x1, int16_t y1, int16_t x2, int16_t y2){
	//Bresenham's line algorithm
	uint16_t index;
	
	int16_t x,y,dx,dy,dx1,dy1,px,py,xe,ye,i;
	dx=x2-x1;
	dy=y2-y1;
	dx1=fabs(dx);
	dy1=fabs(dy);
	px=2*dy1-dx1;
	py=2*dx1-dy1;
	if(dy1<=dx1){
		if(dx>=0){
			x=x1;
			y=y1;
			xe=x2;
		}
		else{
			x=x2;
			y=y2;
			xe=x1;
		}
		index = xy(x,y);
		mask[index] = qadd8( 255, mask[index] );
		for(i=0;x<xe;i++){
			x=x+1;
			if(px<0){
				px=px+2*dy1;
			}
			else{
				if((dx<0 && dy<0) || (dx>0 && dy>0)){
					y=y+1;
				}
				else{
					y=y-1;
				}
				px=px+2*(dy1-dx1);
			}
			delay(0);
			index = xy(x,y);
			mask[index] = qadd8( 255, mask[index] );
		}
	}
	else{
		if(dy>=0){
			x=x1;
			y=y1;
			ye=y2;
		}
		else{
			x=x2;
			y=y2;
			ye=y1;
		}
		index = xy(x,y);
		mask[index] = qadd8( 255, mask[index] );
		for(i=0;y<ye;i++){
			y=y+1;
			if(py<=0){
				py=py+2*dx1;
			}
			else{
				if((dx<0 && dy<0) || (dx>0 && dy>0)){
					x=x+1;
				}
				else{
					x=x-1;
				}
				py=py+2*(dx1-dy1);
			}
			index = xy(x,y);
			mask[index] = qadd8( 255, mask[index] );
		}
	}
}


/**************************************************************************/
/*!
    @brief  Approximates the conversion of a blackbody radiation temperature
            (e.g. 3500K) to a CRGB color object. This can be used within
	    other Pixie color functions like so:
	    
	        pix.color( kelvin_to_rgb( 3000 ) );
		
	    This would render a warm-white color. This measurement system
	    is often used in household LED bulbs, with colors like:
	    
	    - 2700K - **Very Warm White**
	    - 3500K - **Warm White**
	    - 5000K - **White**
	    - 7000K - **Cool White**
	    
    @param  temperature  Blackbody radiation temperature in Kelvin
*/
/**************************************************************************/
CRGB PixieChroma::kelvin_to_rgb(uint16_t temperature){
	// Tanner Helland formula
	float    _temperature;
	float    _red;
	float    _green;
	float    _blue;

	_temperature = constrain(temperature, 0, 65500);

	_red = _green = _blue = 0;  
	float t = _temperature * 0.01;

	if (t <= 66){
		_red = 255;
		_green = (99.4708025861 * log(t)) - 161.1195681661;
		if (t > 19){
			_blue = (138.5177312231 * log(t - 10)) - 305.0447927307;
		}
		else{
			_blue = 0;
		}
	}
	else{
		_red   = 329.698727466  * pow(t - 60, -0.1332047592);
		_green = 288.1221695283 * pow(t - 60, -0.0755148492);
		_blue  = 255;
	}

	float f = 0.01 * 100;

	_red   = constrain(f * _red,   0, 255);
	_green = constrain(f * _green, 0, 255);
	_blue  = constrain(f * _blue,  0, 255);

	return CRGB(_red, _green, _blue);
}


/**************************************************************************/
/*!
    @brief  Freezes the current mask buffer in memory to prevent showing
            unfinished text if show() fires during construction
	        of the current display data. Use free() to unfreeze.
*/
/**************************************************************************/
void PixieChroma::hold(){
	freeze = true;
}


/**************************************************************************/
/*!
    @brief  Unfreezes the current mask buffer in memory to allow showing
            updated text the next time show() is called.
*/
/**************************************************************************/
void PixieChroma::free(){
	freeze = false;
}


/**************************************************************************/
/*!
    @brief  Internal function called by the ANIMATE() ISR, responsible for
            parsing 1D image data into truncated versions sent to the Pixie
	    Chroma displays. ***FastLED.show() is called here.***
*/
/**************************************************************************/
void PixieChroma::show(){
	uint32_t t_now = micros();
	float frame_delta_us = t_now-t_last;
	frame_rate = 1000000.0 / frame_delta_us;
	delta = fps_target / frame_rate;
	
	anim_func(delta); // Call custom animation function
	
	noInterrupts();
	if(!freeze){ // If we're not holding out for a pix.free() call, show with the current mask
		memcpy(mask_out, mask, NUM_VISIBLE_LEDS);
	}
	memcpy(leds_out, leds, sizeof(CRGB)*NUM_VISIBLE_LEDS);

	for(uint16_t i = 0; i < NUM_VISIBLE_LEDS; i+=7){ // NUM VISIBLE always a multiple of 7, this is a slight unrolling of the for loop to save on speed
		// MASKING
		leds_out[i+0].fadeLightBy( 255-mask_out[i+0] ); // Apply mask "over" LED color layer
		leds_out[i+1].fadeLightBy( 255-mask_out[i+1] );
		leds_out[i+2].fadeLightBy( 255-mask_out[i+2] );
		leds_out[i+3].fadeLightBy( 255-mask_out[i+3] );
		leds_out[i+4].fadeLightBy( 255-mask_out[i+4] );
		leds_out[i+5].fadeLightBy( 255-mask_out[i+5] );
		leds_out[i+6].fadeLightBy( 255-mask_out[i+6] );

		// GAMMA CORRECTION
		if(correct_gamma){					
			leds_out[i+0].r = gamma8[leds_out[i+0].r]; // Apply gamma correction LUT
			leds_out[i+0].g = gamma8[leds_out[i+0].g];
			leds_out[i+0].b = gamma8[leds_out[i+0].b];

			leds_out[i+1].r = gamma8[leds_out[i+1].r];
			leds_out[i+1].g = gamma8[leds_out[i+1].g];
			leds_out[i+1].b = gamma8[leds_out[i+1].b];

			leds_out[i+2].r = gamma8[leds_out[i+2].r];
			leds_out[i+2].g = gamma8[leds_out[i+2].g];
			leds_out[i+2].b = gamma8[leds_out[i+2].b];

			leds_out[i+3].r = gamma8[leds_out[i+3].r];
			leds_out[i+3].g = gamma8[leds_out[i+3].g];
			leds_out[i+3].b = gamma8[leds_out[i+3].b];

			leds_out[i+4].r = gamma8[leds_out[i+4].r];
			leds_out[i+4].g = gamma8[leds_out[i+4].g];
			leds_out[i+4].b = gamma8[leds_out[i+4].b];

			leds_out[i+5].r = gamma8[leds_out[i+5].r];
			leds_out[i+5].g = gamma8[leds_out[i+5].g];
			leds_out[i+5].b = gamma8[leds_out[i+5].b];

			leds_out[i+6].r = gamma8[leds_out[i+6].r];
			leds_out[i+6].g = gamma8[leds_out[i+6].g];
			leds_out[i+6].b = gamma8[leds_out[i+6].b];
		}
	}
		
	// Regulate brightness to keep power within budget set with pix.set_max_power(V, mA);
	FastLED.setBrightness(calculate_max_brightness_for_power_vmA(leds_out, NUM_VISIBLE_LEDS, brightness_level, max_V, max_mA));
	FastLED.show();

	interrupts();
	
	t_last = t_now;
}

// ---------------------------------------------------------------------------------------------------------|
// -- PRIVATE CLASS FUNCTIONS ------------------------------------------------------------------------------|
// ---------------------------------------------------------------------------------------------------------|

void PixieChroma::build_controller(const uint8_t pin){
	// FastLED control pin has to be defined as a constant, (not just declared const, it's weirdly different) so
	// this is a hacky workaround. Since we have to hardwire the damn pin number variable, we also have
	// to be careful of the current architecture we're compiling to, since FastLED doesn't let you 
	// define non-existent pins either.
	
	#ifdef ESP8266
		if (pin == 0){FastLED.addLeds<WS2812B, 0, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 1){FastLED.addLeds<WS2812B, 1, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 2){FastLED.addLeds<WS2812B, 2, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 3){FastLED.addLeds<WS2812B, 3, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 4){FastLED.addLeds<WS2812B, 4, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 5){FastLED.addLeds<WS2812B, 5, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
			// annnnd a bunch of missing pins that are tied to external flash...
		if (pin == 12){FastLED.addLeds<WS2812B, 12, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 13){FastLED.addLeds<WS2812B, 13, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 14){FastLED.addLeds<WS2812B, 14, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 15){FastLED.addLeds<WS2812B, 15, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 16){FastLED.addLeds<WS2812B, 16, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
	#endif
	
	#ifdef ESP32
		if (pin == 0){FastLED.addLeds<WS2812B, 0, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 1){FastLED.addLeds<WS2812B, 1, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 2){FastLED.addLeds<WS2812B, 2, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 3){FastLED.addLeds<WS2812B, 3, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 4){FastLED.addLeds<WS2812B, 4, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 5){FastLED.addLeds<WS2812B, 5, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 12){FastLED.addLeds<WS2812B, 12, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 13){FastLED.addLeds<WS2812B, 13, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 14){FastLED.addLeds<WS2812B, 14, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 15){FastLED.addLeds<WS2812B, 15, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 16){FastLED.addLeds<WS2812B, 16, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 17){FastLED.addLeds<WS2812B, 17, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 18){FastLED.addLeds<WS2812B, 18, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 19){FastLED.addLeds<WS2812B, 19, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 21){FastLED.addLeds<WS2812B, 21, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 22){FastLED.addLeds<WS2812B, 22, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 23){FastLED.addLeds<WS2812B, 23, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 25){FastLED.addLeds<WS2812B, 25, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 26){FastLED.addLeds<WS2812B, 26, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 27){FastLED.addLeds<WS2812B, 27, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 32){FastLED.addLeds<WS2812B, 32, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 33){FastLED.addLeds<WS2812B, 33, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
	#endif
	
	#ifdef SAMD_SERIES
		if (pin == 0){FastLED.addLeds<WS2812B, 0, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 1){FastLED.addLeds<WS2812B, 1, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 2){FastLED.addLeds<WS2812B, 2, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 3){FastLED.addLeds<WS2812B, 3, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 4){FastLED.addLeds<WS2812B, 4, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 5){FastLED.addLeds<WS2812B, 5, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 6){FastLED.addLeds<WS2812B, 6, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 7){FastLED.addLeds<WS2812B, 7, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 8){FastLED.addLeds<WS2812B, 8, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 9){FastLED.addLeds<WS2812B, 9, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
		if (pin == 10){FastLED.addLeds<WS2812B, 10, GRB>(leds_out, NUM_VISIBLE_LEDS).setCorrection(TypicalLEDStrip);}
	#endif
}

// TODO: Remove debugging Serial.print() calls from library
void PixieChroma::calc_xy(){
  // Initialize XY table
	for(uint16_t yi = 0; yi < chars_y; yi++){
		for(uint16_t y = 0; y < 11; y++){
			for(uint16_t xi = 0; xi < chars_x; xi++){
				for(uint16_t x = 0; x < 7; x++){
					int16_t x_pos = (xi*display_width)+x;
					int16_t y_pos = (yi*display_height)+y;

					int16_t x_pos_mod = x_pos % display_width;
					int16_t y_pos_mod = y_pos % display_height;

					uint16_t i_table = (y_pos * matrix_width) + x_pos;
					uint16_t i_template = (y_pos_mod * display_width) + x_pos_mod;

					xy_table[i_table] = int8_t(pgm_read_byte(xy_template + i_template));
				}
			}
		}
	}

	Serial.println("SOLVING VISIBLE");

	// Initialize first row of displays
	uint8_t visible_rows = 0;
	for(uint16_t row = 0; row < display_height; row++){
		uint16_t index = (5*visible_rows);
		bool found_visible = false;
		int16_t last_data = 0;
		for(uint16_t col = 0; col < matrix_width; col++){
			uint16_t i = (row*matrix_width)+col;
			int16_t map_data = xy_table[i];

			if(map_data == -1){
				xy_table[i] = index;
				index++;
				found_visible = true;
			}

			else if(map_data == -2){
				if(last_data == -1){
					index+=30;
				}
			}

			last_data = map_data;
		}

		if(found_visible){
			visible_rows++;
		}
	}

	NUM_VISIBLE_LEDS = 35*chars_x; // account for first row

	// Solve additional rows
	if(chars_y > 1){
		uint8_t rows_left = chars_y-1;
		uint16_t row_length = (display_width*display_height)*chars_x;
		for(uint8_t ii = 0; ii < rows_left; ii++){
			for(uint16_t r = 0; r < row_length; r++){
				uint16_t final_src_index = (ii*row_length)+r;
				int16_t src_data = xy_table[final_src_index];
				if(src_data >= 0){
					src_data += (35*chars_x);

					if(src_data > NUM_VISIBLE_LEDS){
						NUM_VISIBLE_LEDS = src_data;
					}
					xy_table[final_src_index+row_length] = src_data;
				}
			}
		}
	}

	uint16_t index = NUM_VISIBLE_LEDS;
	Serial.println(NUM_VISIBLE_LEDS);
	Serial.println(NUM_LEDS);

	Serial.println("SOLVING INVISIBLE");
	for(uint16_t y = 0; y < matrix_height; y++){
		for(uint16_t x = 0; x < matrix_width; x++){
			uint16_t i = (y * matrix_width) + x;
			uint16_t j = xy_table[i];

			if(xy_table[i] == -2){
				xy_table[i] = index;
				index++;
			}
		}
	}
	Serial.println("DONE");

	for(uint16_t y = 0; y < matrix_height; y++){
		for(uint16_t x = 0; x < matrix_width; x++){
			uint16_t i = (y * matrix_width) + x;
			Serial.print(xy_table[i]);
			Serial.print('\t');
		}
		Serial.println();
	}
}

void PixieChroma::print_xy_map(){
	for(uint8_t y = 0; y < matrix_height; y++){
		for(uint8_t x = 0; x < matrix_width; x++){
			uint16_t index = (matrix_width*y)+x;
			Serial.print(xy_table[index]);
			Serial.print('\t');
		}
		Serial.println();
	}
}