Adafruit_GFX.cpp

/*
This is the core graphics library for all our displays, providing a common
set of graphics primitives (points, lines, circles, etc.).  It needs to be
paired with a hardware-specific library for each display device we carry
(to handle the lower-level functions).

Adafruit invests time and resources providing this open source code, please
support Adafruit & open-source hardware by purchasing products from Adafruit!

Copyright (c) 2013 Adafruit Industries.  All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

- Redistributions of source code must retain the above copyright notice,
  this list of conditions and the following disclaimer.
- Redistributions in binary form must reproduce the above copyright notice,
  this list of conditions and the following disclaimer in the documentation
  and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
 */

/* Includes changes made for mpd_oled */

#include "Adafruit_GFX.h"
#include "./ArduiPi_OLED_lib.h"
#include "glcdfont.c"
#ifdef __AVR__
#include <avr/pgmspace.h>
#elif defined(ESP8266) || defined(ESP32)
#include <pgmspace.h>
#endif

#include <algorithm>

using std::swap;

// Many (but maybe not all) non-AVR board installs define macros
// for compatibility with existing PROGMEM-reading AVR code.
// Do our own checks and defines here for good measure...

#ifndef pgm_read_byte
#define pgm_read_byte(addr) (*(const unsigned char *)(addr))
#endif
#ifndef pgm_read_word
#define pgm_read_word(addr) (*(const unsigned short *)(addr))
#endif
#ifndef pgm_read_dword
#define pgm_read_dword(addr) (*(const unsigned long *)(addr))
#endif

// Pointers are a peculiar case...typically 16-bit on AVR boards,
// 32 bits elsewhere.  Try to accommodate both...

#if !defined(__INT_MAX__) || (__INT_MAX__ > 0xFFFF)
#define pgm_read_pointer(addr) ((void *)pgm_read_dword(addr))
#else
#define pgm_read_pointer(addr) ((void *)pgm_read_word(addr))
#endif

void Adafruit_GFX::reset(int16_t w, int16_t h)
{
  _width = w;
  _height = h;
  rotation = 0;
  cursor_y = cursor_x = 0;
  textsize = 1;
  textcolor = textbgcolor = 0xFFFF;
  wrap = true;
  _cp437 = false;
  gfxFont = NULL;
}

Adafruit_GFX::Adafruit_GFX(int16_t w, int16_t h) : WIDTH(w), HEIGHT(h)
{
  reset(WIDTH, HEIGHT);
}

// Bresenham's algorithm - thx wikpedia
void Adafruit_GFX::writeLine(int16_t x0, int16_t y0, int16_t x1, int16_t y1,
                             uint16_t color)
{
  int16_t steep = abs(y1 - y0) > abs(x1 - x0);
  if (steep) {
    swap(x0, y0);
    swap(x1, y1);
  }

  if (x0 > x1) {
    swap(x0, x1);
    swap(y0, y1);
  }

  int16_t dx, dy;
  dx = x1 - x0;
  dy = abs(y1 - y0);

  int16_t err = dx / 2;
  int16_t ystep;

  if (y0 < y1) {
    ystep = 1;
  }
  else {
    ystep = -1;
  }

  for (; x0 <= x1; x0++) {
    if (steep) {
      writePixel(y0, x0, color);
    }
    else {
      writePixel(x0, y0, color);
    }
    err -= dy;
    if (err < 0) {
      y0 += ystep;
      err += dx;
    }
  }
}

void Adafruit_GFX::startWrite()
{
  // Overwrite in subclasses if desired!
}

void Adafruit_GFX::writePixel(int16_t x, int16_t y, uint16_t color)
{
  // Overwrite in subclasses if startWrite is defined!
  drawPixel(x, y, color);
}

// (x,y) is topmost point; if unsure, calling function
// should sort endpoints or call writeLine() instead
void Adafruit_GFX::writeFastVLine(int16_t x, int16_t y, int16_t h,
                                  uint16_t color)
{
  // Overwrite in subclasses if startWrite is defined!
  // Can be just writeLine(x, y, x, y+h-1, color);
  // or writeFillRect(x, y, 1, h, color);
  drawFastVLine(x, y, h, color);
}

// (x,y) is leftmost point; if unsure, calling function
// should sort endpoints or call writeLine() instead
void Adafruit_GFX::writeFastHLine(int16_t x, int16_t y, int16_t w,
                                  uint16_t color)
{
  // Overwrite in subclasses if startWrite is defined!
  // Example: writeLine(x, y, x+w-1, y, color);
  // or writeFillRect(x, y, w, 1, color);
  drawFastHLine(x, y, w, color);
}

void Adafruit_GFX::writeFillRect(int16_t x, int16_t y, int16_t w, int16_t h,
                                 uint16_t color)
{
  // Overwrite in subclasses if desired!
  fillRect(x, y, w, h, color);
}

void Adafruit_GFX::endWrite()
{
  // Overwrite in subclasses if startWrite is defined!
}

// (x,y) is topmost point; if unsure, calling function
// should sort endpoints or call drawLine() instead
void Adafruit_GFX::drawFastVLine(int16_t x, int16_t y, int16_t h,
                                 uint16_t color)
{
  // Update in subclasses if desired!
  startWrite();
  writeLine(x, y, x, y + h - 1, color);
  endWrite();
}

// (x,y) is leftmost point; if unsure, calling function
// should sort endpoints or call drawLine() instead
void Adafruit_GFX::drawFastHLine(int16_t x, int16_t y, int16_t w,
                                 uint16_t color)
{
  // Update in subclasses if desired!
  startWrite();
  writeLine(x, y, x + w - 1, y, color);
  endWrite();
}

void Adafruit_GFX::fillRect(int16_t x, int16_t y, int16_t w, int16_t h,
                            uint16_t color)
{
  // Update in subclasses if desired!
  startWrite();
  for (int16_t i = x; i < x + w; i++) {
    writeFastVLine(i, y, h, color);
  }
  endWrite();
}

void Adafruit_GFX::fillScreen(uint16_t color)
{
  // Update in subclasses if desired!
  fillRect(0, 0, _width, _height, color);
}

void Adafruit_GFX::drawLine(int16_t x0, int16_t y0, int16_t x1, int16_t y1,
                            uint16_t color)
{
  // Update in subclasses if desired!
  if (x0 == x1) {
    if (y0 > y1)
      swap(y0, y1);
    drawFastVLine(x0, y0, y1 - y0 + 1, color);
  }
  else if (y0 == y1) {
    if (x0 > x1)
      swap(x0, x1);
    drawFastHLine(x0, y0, x1 - x0 + 1, color);
  }
  else {
    startWrite();
    writeLine(x0, y0, x1, y1, color);
    endWrite();
  }
}

// Draw a circle outline
void Adafruit_GFX::drawCircle(int16_t x0, int16_t y0, int16_t r, uint16_t color)
{
  int16_t f = 1 - r;
  int16_t ddF_x = 1;
  int16_t ddF_y = -2 * r;
  int16_t x = 0;
  int16_t y = r;

  startWrite();
  writePixel(x0, y0 + r, color);
  writePixel(x0, y0 - r, color);
  writePixel(x0 + r, y0, color);
  writePixel(x0 - r, y0, color);

  while (x < y) {
    if (f >= 0) {
      y--;
      ddF_y += 2;
      f += ddF_y;
    }
    x++;
    ddF_x += 2;
    f += ddF_x;

    writePixel(x0 + x, y0 + y, color);
    writePixel(x0 - x, y0 + y, color);
    writePixel(x0 + x, y0 - y, color);
    writePixel(x0 - x, y0 - y, color);
    writePixel(x0 + y, y0 + x, color);
    writePixel(x0 - y, y0 + x, color);
    writePixel(x0 + y, y0 - x, color);
    writePixel(x0 - y, y0 - x, color);
  }
  endWrite();
}

void Adafruit_GFX::drawCircleHelper(int16_t x0, int16_t y0, int16_t r,
                                    uint8_t cornername, uint16_t color)
{
  int16_t f = 1 - r;
  int16_t ddF_x = 1;
  int16_t ddF_y = -2 * r;
  int16_t x = 0;
  int16_t y = r;

  while (x < y) {
    if (f >= 0) {
      y--;
      ddF_y += 2;
      f += ddF_y;
    }
    x++;
    ddF_x += 2;
    f += ddF_x;
    if (cornername & 0x4) {
      writePixel(x0 + x, y0 + y, color);
      writePixel(x0 + y, y0 + x, color);
    }
    if (cornername & 0x2) {
      writePixel(x0 + x, y0 - y, color);
      writePixel(x0 + y, y0 - x, color);
    }
    if (cornername & 0x8) {
      writePixel(x0 - y, y0 + x, color);
      writePixel(x0 - x, y0 + y, color);
    }
    if (cornername & 0x1) {
      writePixel(x0 - y, y0 - x, color);
      writePixel(x0 - x, y0 - y, color);
    }
  }
}

void Adafruit_GFX::fillCircle(int16_t x0, int16_t y0, int16_t r, uint16_t color)
{
  startWrite();
  writeFastVLine(x0, y0 - r, 2 * r + 1, color);
  fillCircleHelper(x0, y0, r, 3, 0, color);
  endWrite();
}

// Used to do circles and roundrects
void Adafruit_GFX::fillCircleHelper(int16_t x0, int16_t y0, int16_t r,
                                    uint8_t cornername, int16_t delta,
                                    uint16_t color)
{

  int16_t f = 1 - r;
  int16_t ddF_x = 1;
  int16_t ddF_y = -2 * r;
  int16_t x = 0;
  int16_t y = r;

  while (x < y) {
    if (f >= 0) {
      y--;
      ddF_y += 2;
      f += ddF_y;
    }
    x++;
    ddF_x += 2;
    f += ddF_x;

    if (cornername & 0x1) {
      writeFastVLine(x0 + x, y0 - y, 2 * y + 1 + delta, color);
      writeFastVLine(x0 + y, y0 - x, 2 * x + 1 + delta, color);
    }
    if (cornername & 0x2) {
      writeFastVLine(x0 - x, y0 - y, 2 * y + 1 + delta, color);
      writeFastVLine(x0 - y, y0 - x, 2 * x + 1 + delta, color);
    }
  }
}

// Draw a rectangle
void Adafruit_GFX::drawRect(int16_t x, int16_t y, int16_t w, int16_t h,
                            uint16_t color)
{
  startWrite();
  writeFastHLine(x, y, w, color);
  writeFastHLine(x, y + h - 1, w, color);
  writeFastVLine(x, y, h, color);
  writeFastVLine(x + w - 1, y, h, color);
  endWrite();
}

// Draw a rounded rectangle
void Adafruit_GFX::drawRoundRect(int16_t x, int16_t y, int16_t w, int16_t h,
                                 int16_t r, uint16_t color)
{
  // smarter version
  startWrite();
  writeFastHLine(x + r, y, w - 2 * r, color);         // Top
  writeFastHLine(x + r, y + h - 1, w - 2 * r, color); // Bottom
  writeFastVLine(x, y + r, h - 2 * r, color);         // Left
  writeFastVLine(x + w - 1, y + r, h - 2 * r, color); // Right
  // draw four corners
  drawCircleHelper(x + r, y + r, r, 1, color);
  drawCircleHelper(x + w - r - 1, y + r, r, 2, color);
  drawCircleHelper(x + w - r - 1, y + h - r - 1, r, 4, color);
  drawCircleHelper(x + r, y + h - r - 1, r, 8, color);
  endWrite();
}

// Fill a rounded rectangle
void Adafruit_GFX::fillRoundRect(int16_t x, int16_t y, int16_t w, int16_t h,
                                 int16_t r, uint16_t color)
{
  // smarter version
  startWrite();
  writeFillRect(x + r, y, w - 2 * r, h, color);

  // draw four corners
  fillCircleHelper(x + w - r - 1, y + r, r, 1, h - 2 * r - 1, color);
  fillCircleHelper(x + r, y + r, r, 2, h - 2 * r - 1, color);
  endWrite();
}

// Draw a triangle
void Adafruit_GFX::drawTriangle(int16_t x0, int16_t y0, int16_t x1, int16_t y1,
                                int16_t x2, int16_t y2, uint16_t color)
{
  drawLine(x0, y0, x1, y1, color);
  drawLine(x1, y1, x2, y2, color);
  drawLine(x2, y2, x0, y0, color);
}

// Fill a triangle
void Adafruit_GFX::fillTriangle(int16_t x0, int16_t y0, int16_t x1, int16_t y1,
                                int16_t x2, int16_t y2, uint16_t color)
{

  int16_t a, b, y, last;

  // Sort coordinates by Y order (y2 >= y1 >= y0)
  if (y0 > y1) {
    swap(y0, y1);
    swap(x0, x1);
  }
  if (y1 > y2) {
    swap(y2, y1);
    swap(x2, x1);
  }
  if (y0 > y1) {
    swap(y0, y1);
    swap(x0, x1);
  }

  startWrite();
  if (y0 == y2) { // Handle awkward all-on-same-line case as its own thing
    a = b = x0;
    if (x1 < a)
      a = x1;
    else if (x1 > b)
      b = x1;
    if (x2 < a)
      a = x2;
    else if (x2 > b)
      b = x2;
    writeFastHLine(a, y0, b - a + 1, color);
    endWrite();
    return;
  }

  int16_t dx01 = x1 - x0, dy01 = y1 - y0, dx02 = x2 - x0, dy02 = y2 - y0,
          dx12 = x2 - x1, dy12 = y2 - y1;
  int32_t sa = 0, sb = 0;

  // For upper part of triangle, find scanline crossings for segments
  // 0-1 and 0-2.  If y1=y2 (flat-bottomed triangle), the scanline y1
  // is included here (and second loop will be skipped, avoiding a /0
  // error there), otherwise scanline y1 is skipped here and handled
  // in the second loop...which also avoids a /0 error here if y0=y1
  // (flat-topped triangle).
  if (y1 == y2)
    last = y1; // Include y1 scanline
  else
    last = y1 - 1; // Skip it

  for (y = y0; y <= last; y++) {
    a = x0 + sa / dy01;
    b = x0 + sb / dy02;
    sa += dx01;
    sb += dx02;
    /* longhand:
    a = x0 + (x1 - x0) * (y - y0) / (y1 - y0);
    b = x0 + (x2 - x0) * (y - y0) / (y2 - y0);
    */
    if (a > b)
      swap(a, b);
    writeFastHLine(a, y, b - a + 1, color);
  }

  // For lower part of triangle, find scanline crossings for segments
  // 0-2 and 1-2.  This loop is skipped if y1=y2.
  sa = dx12 * (y - y1);
  sb = dx02 * (y - y0);
  for (; y <= y2; y++) {
    a = x1 + sa / dy12;
    b = x0 + sb / dy02;
    sa += dx12;
    sb += dx02;
    /* longhand:
    a = x1 + (x2 - x1) * (y - y1) / (y2 - y1);
    b = x0 + (x2 - x0) * (y - y0) / (y2 - y0);
    */
    if (a > b)
      swap(a, b);
    writeFastHLine(a, y, b - a + 1, color);
  }
  endWrite();
}

// BITMAP / XBITMAP / GRAYSCALE / RGB BITMAP FUNCTIONS ---------------------

// Draw a PROGMEM-resident 1-bit image at the specified (x,y) position,
// using the specified foreground color (unset bits are transparent).
void Adafruit_GFX::drawBitmap(int16_t x, int16_t y, const uint8_t bitmap[],
                              int16_t w, int16_t h, uint16_t color)
{

  int16_t byteWidth = (w + 7) / 8; // Bitmap scanline pad = whole byte
  uint8_t byte = 0;

  startWrite();
  for (int16_t j = 0; j < h; j++, y++) {
    for (int16_t i = 0; i < w; i++) {
      if (i & 7)
        byte <<= 1;
      else
        byte = pgm_read_byte(&bitmap[j * byteWidth + i / 8]);
      if (byte & 0x80)
        writePixel(x + i, y, color);
    }
  }
  endWrite();
}

// Draw a PROGMEM-resident 1-bit image at the specified (x,y) position,
// using the specified foreground (for set bits) and background (unset
// bits) colors.
void Adafruit_GFX::drawBitmap(int16_t x, int16_t y, const uint8_t bitmap[],
                              int16_t w, int16_t h, uint16_t color, uint16_t bg)
{

  int16_t byteWidth = (w + 7) / 8; // Bitmap scanline pad = whole byte
  uint8_t byte = 0;

  startWrite();
  for (int16_t j = 0; j < h; j++, y++) {
    for (int16_t i = 0; i < w; i++) {
      if (i & 7)
        byte <<= 1;
      else
        byte = pgm_read_byte(&bitmap[j * byteWidth + i / 8]);
      writePixel(x + i, y, (byte & 0x80) ? color : bg);
    }
  }
  endWrite();
}

// Draw a RAM-resident 1-bit image at the specified (x,y) position,
// using the specified foreground color (unset bits are transparent).
void Adafruit_GFX::drawBitmap(int16_t x, int16_t y, uint8_t *bitmap, int16_t w,
                              int16_t h, uint16_t color)
{

  int16_t byteWidth = (w + 7) / 8; // Bitmap scanline pad = whole byte
  uint8_t byte = 0;

  startWrite();
  for (int16_t j = 0; j < h; j++, y++) {
    for (int16_t i = 0; i < w; i++) {
      if (i & 7)
        byte <<= 1;
      else
        byte = bitmap[j * byteWidth + i / 8];
      if (byte & 0x80)
        writePixel(x + i, y, color);
    }
  }
  endWrite();
}

// Draw a RAM-resident 1-bit image at the specified (x,y) position,
// using the specified foreground (for set bits) and background (unset
// bits) colors.
void Adafruit_GFX::drawBitmap(int16_t x, int16_t y, uint8_t *bitmap, int16_t w,
                              int16_t h, uint16_t color, uint16_t bg)
{

  int16_t byteWidth = (w + 7) / 8; // Bitmap scanline pad = whole byte
  uint8_t byte = 0;

  startWrite();
  for (int16_t j = 0; j < h; j++, y++) {
    for (int16_t i = 0; i < w; i++) {
      if (i & 7)
        byte <<= 1;
      else
        byte = bitmap[j * byteWidth + i / 8];
      writePixel(x + i, y, (byte & 0x80) ? color : bg);
    }
  }
  endWrite();
}

// Draw PROGMEM-resident XBitMap Files (*.xbm), exported from GIMP,
// Usage: Export from GIMP to *.xbm, rename *.xbm to *.c and open in editor.
// C Array can be directly used with this function.
// There is no RAM-resident version of this function; if generating bitmaps
// in RAM, use the format defined by drawBitmap() and call that instead.
void Adafruit_GFX::drawXBitmap(int16_t x, int16_t y, const uint8_t bitmap[],
                               int16_t w, int16_t h, uint16_t color)
{

  int16_t byteWidth = (w + 7) / 8; // Bitmap scanline pad = whole byte
  uint8_t byte = 0;

  startWrite();
  for (int16_t j = 0; j < h; j++, y++) {
    for (int16_t i = 0; i < w; i++) {
      if (i & 7)
        byte >>= 1;
      else
        byte = pgm_read_byte(&bitmap[j * byteWidth + i / 8]);
      // Nearly identical to drawBitmap(), only the bit order
      // is reversed here (left-to-right = LSB to MSB):
      if (byte & 0x01)
        writePixel(x + i, y, color);
    }
  }
  endWrite();
}

// Draw a PROGMEM-resident 8-bit image (grayscale) at the specified (x,y)
// pos.  Specifically for 8-bit display devices such as IS31FL3731;
// no color reduction/expansion is performed.
void Adafruit_GFX::drawGrayscaleBitmap(int16_t x, int16_t y,
                                       const uint8_t bitmap[], int16_t w,
                                       int16_t h)
{
  startWrite();
  for (int16_t j = 0; j < h; j++, y++) {
    for (int16_t i = 0; i < w; i++) {
      writePixel(x + i, y, (uint8_t)pgm_read_byte(&bitmap[j * w + i]));
    }
  }
  endWrite();
}

// Draw a RAM-resident 8-bit image (grayscale) at the specified (x,y)
// pos.  Specifically for 8-bit display devices such as IS31FL3731;
// no color reduction/expansion is performed.
void Adafruit_GFX::drawGrayscaleBitmap(int16_t x, int16_t y, uint8_t *bitmap,
                                       int16_t w, int16_t h)
{
  startWrite();
  for (int16_t j = 0; j < h; j++, y++) {
    for (int16_t i = 0; i < w; i++) {
      writePixel(x + i, y, bitmap[j * w + i]);
    }
  }
  endWrite();
}

// Draw a PROGMEM-resident 8-bit image (grayscale) with a 1-bit mask
// (set bits = opaque, unset bits = clear) at the specified (x,y) position.
// BOTH buffers (grayscale and mask) must be PROGMEM-resident.
// Specifically for 8-bit display devices such as IS31FL3731;
// no color reduction/expansion is performed.
void Adafruit_GFX::drawGrayscaleBitmap(int16_t x, int16_t y,
                                       const uint8_t bitmap[],
                                       const uint8_t mask[], int16_t w,
                                       int16_t h)
{
  int16_t bw = (w + 7) / 8; // Bitmask scanline pad = whole byte
  uint8_t byte = 0;
  startWrite();
  for (int16_t j = 0; j < h; j++, y++) {
    for (int16_t i = 0; i < w; i++) {
      if (i & 7)
        byte <<= 1;
      else
        byte = pgm_read_byte(&mask[j * bw + i / 8]);
      if (byte & 0x80) {
        writePixel(x + i, y, (uint8_t)pgm_read_byte(&bitmap[j * w + i]));
      }
    }
  }
  endWrite();
}

// Draw a RAM-resident 8-bit image (grayscale) with a 1-bit mask
// (set bits = opaque, unset bits = clear) at the specified (x,y) pos.
// BOTH buffers (grayscale and mask) must be RAM-resident, no mix-and-
// match.  Specifically for 8-bit display devices such as IS31FL3731;
// no color reduction/expansion is performed.
void Adafruit_GFX::drawGrayscaleBitmap(int16_t x, int16_t y, uint8_t *bitmap,
                                       uint8_t *mask, int16_t w, int16_t h)
{
  int16_t bw = (w + 7) / 8; // Bitmask scanline pad = whole byte
  uint8_t byte = 0;
  startWrite();
  for (int16_t j = 0; j < h; j++, y++) {
    for (int16_t i = 0; i < w; i++) {
      if (i & 7)
        byte <<= 1;
      else
        byte = mask[j * bw + i / 8];
      if (byte & 0x80) {
        writePixel(x + i, y, bitmap[j * w + i]);
      }
    }
  }
  endWrite();
}

// Draw a PROGMEM-resident 16-bit image (RGB 5/6/5) at the specified (x,y)
// position.  For 16-bit display devices; no color reduction performed.
void Adafruit_GFX::drawRGBBitmap(int16_t x, int16_t y, const uint16_t bitmap[],
                                 int16_t w, int16_t h)
{
  startWrite();
  for (int16_t j = 0; j < h; j++, y++) {
    for (int16_t i = 0; i < w; i++) {
      writePixel(x + i, y, pgm_read_word(&bitmap[j * w + i]));
    }
  }
  endWrite();
}

// Draw a RAM-resident 16-bit image (RGB 5/6/5) at the specified (x,y)
// position.  For 16-bit display devices; no color reduction performed.
void Adafruit_GFX::drawRGBBitmap(int16_t x, int16_t y, uint16_t *bitmap,
                                 int16_t w, int16_t h)
{
  startWrite();
  for (int16_t j = 0; j < h; j++, y++) {
    for (int16_t i = 0; i < w; i++) {
      writePixel(x + i, y, bitmap[j * w + i]);
    }
  }
  endWrite();
}

// Draw a PROGMEM-resident 16-bit image (RGB 5/6/5) with a 1-bit mask
// (set bits = opaque, unset bits = clear) at the specified (x,y) position.
// BOTH buffers (color and mask) must be PROGMEM-resident.
// For 16-bit display devices; no color reduction performed.
void Adafruit_GFX::drawRGBBitmap(int16_t x, int16_t y, const uint16_t bitmap[],
                                 const uint8_t mask[], int16_t w, int16_t h)
{
  int16_t bw = (w + 7) / 8; // Bitmask scanline pad = whole byte
  uint8_t byte = 0;
  startWrite();
  for (int16_t j = 0; j < h; j++, y++) {
    for (int16_t i = 0; i < w; i++) {
      if (i & 7)
        byte <<= 1;
      else
        byte = pgm_read_byte(&mask[j * bw + i / 8]);
      if (byte & 0x80) {
        writePixel(x + i, y, pgm_read_word(&bitmap[j * w + i]));
      }
    }
  }
  endWrite();
}

// Draw a RAM-resident 16-bit image (RGB 5/6/5) with a 1-bit mask
// (set bits = opaque, unset bits = clear) at the specified (x,y) pos.
// BOTH buffers (color and mask) must be RAM-resident, no mix-and-match.
// For 16-bit display devices; no color reduction performed.
void Adafruit_GFX::drawRGBBitmap(int16_t x, int16_t y, uint16_t *bitmap,
                                 uint8_t *mask, int16_t w, int16_t h)
{
  int16_t bw = (w + 7) / 8; // Bitmask scanline pad = whole byte
  uint8_t byte = 0;
  startWrite();
  for (int16_t j = 0; j < h; j++, y++) {
    for (int16_t i = 0; i < w; i++) {
      if (i & 7)
        byte <<= 1;
      else
        byte = mask[j * bw + i / 8];
      if (byte & 0x80) {
        writePixel(x + i, y, bitmap[j * w + i]);
      }
    }
  }
  endWrite();
}

// TEXT- AND CHARACTER-HANDLING FUNCTIONS ----------------------------------

// Draw a character
void Adafruit_GFX::drawCharPart(int16_t x, int16_t y, int x_off_start,
                                int x_off_end, unsigned char c, uint16_t color,
                                uint16_t bg, uint8_t size)
{
  if (x_off_start >= x_off_end)
    return;

  x -= x_off_start;

  if (!gfxFont) { // 'Classic' built-in font

    if ((x >= _width + 6 * size) ||  // Clip right
        (y >= _height + 8 * size) || // Clip bottom
        (x - 1 + 6 * size < 0) ||    // Clip left
        (y - 1 + 8 * size < 0))      // Clip top
                                     //((x + 6 * size - 1) < 0) || // Clip left
                                     //((y + 8 * size - 1) < 0))   // Clip top
      return;

    if (!_cp437 && (c >= 176))
      c++; // Handle 'classic' charset behavior

    startWrite();
    for (int8_t i = 0; i < 6; i++) {              // Char bitmap = 5 columns
      int x_off_pix_start = i * size;             // unclipped start
      int x_off_pix_end = x_off_pix_start + size; // unclipped end

      if (x_off_start >= x_off_pix_end)
        continue; // start is past pix end
      else if (x_off_start > x_off_pix_start)
        x_off_pix_start = x_off_start; // clipped pix start

      if (x_off_end <= x_off_pix_start)
        break; // pix start is past end
      else if (x_off_end < x_off_pix_end)
        x_off_pix_end = x_off_end; // clipped pix end

      int pix_width = x_off_pix_end - x_off_pix_start; // printable width
      if (pix_width < 1)
        break;

      if (i < 5) {
        uint8_t line = pgm_read_byte(&font[c * 5 + i]);
        for (int8_t j = 0; j < 8; j++, line >>= 1) {
          if (line & 1) {
            if (size == 1)
              writePixel(x + i, y + j, color);
            else
              writeFillRect(x + x_off_pix_start, y + j * size, pix_width, size,
                            color);
          }
          else if (bg != color) {
            if (size == 1)
              writePixel(x + i, y + j, bg);
            else
              writeFillRect(x + x_off_pix_start, y + j * size, pix_width, size,
                            bg);
          }
        }
      }
      else {
        if (bg != color) { // If opaque, draw vert line for last column
          if (size == 1)
            writeFastVLine(x + 5, y, 8, bg);
          else
            writeFillRect(x + x_off_pix_start, y, pix_width, 8 * size, bg);
        }
      }
    }
    endWrite();
  }
}

// Draw a character
void Adafruit_GFX::drawChar(int16_t x, int16_t y, unsigned char c,
                            uint16_t color, uint16_t bg, uint8_t size)
{

  if (!gfxFont) { // 'Classic' built-in font

    if ((x >= _width + 6 * size) ||  // Clip right
        (y >= _height + 8 * size) || // Clip bottom
        (x - 1 + 6 * size < 0) ||    // Clip left
        (y - 1 + 8 * size < 0))      // Clip top
                                     //((x + 6 * size - 1) < 0) || // Clip left
                                     //((y + 8 * size - 1) < 0))   // Clip top
      return;

    if (!_cp437 && (c >= 176))
      c++; // Handle 'classic' charset behavior

    startWrite();
    for (int8_t i = 0; i < 5; i++) { // Char bitmap = 5 columns
      uint8_t line = pgm_read_byte(&font[c * 5 + i]);
      for (int8_t j = 0; j < 8; j++, line >>= 1) {
        if (line & 1) {
          if (size == 1)
            writePixel(x + i, y + j, color);
          else
            writeFillRect(x + i * size, y + j * size, size, size, color);
        }
        else if (bg != color) {
          if (size == 1)
            writePixel(x + i, y + j, bg);
          else
            writeFillRect(x + i * size, y + j * size, size, size, bg);
        }
      }
    }
    if (bg != color) { // If opaque, draw vertical line for last column
      if (size == 1)
        writeFastVLine(x + 5, y, 8, bg);
      else
        writeFillRect(x + 5 * size, y, size, 8 * size, bg);
    }
    endWrite();
  }
  else { // Custom font

    // Character is assumed previously filtered by write() to eliminate
    // newlines, returns, non-printable characters, etc.  Calling
    // drawChar() directly with 'bad' characters of font may cause mayhem!

    c -= (uint8_t)pgm_read_byte(&gfxFont->first);
    GFXglyph *glyph = &(((GFXglyph *)pgm_read_pointer(&gfxFont->glyph))[c]);
    uint8_t *bitmap = (uint8_t *)pgm_read_pointer(&gfxFont->bitmap);

    uint16_t bo = pgm_read_word(&glyph->bitmapOffset);
    uint8_t w = pgm_read_byte(&glyph->width), h = pgm_read_byte(&glyph->height);
    int8_t xo = pgm_read_byte(&glyph->xOffset),
           yo = pgm_read_byte(&glyph->yOffset);
    uint8_t xx, yy, bits = 0, bit = 0;
    int16_t xo16 = 0, yo16 = 0;

    if (size > 1) {
      xo16 = xo;
      yo16 = yo;
    }

    // Todo: Add character clipping here

    // NOTE: THERE IS NO 'BACKGROUND' COLOR OPTION ON CUSTOM FONTS.
    // THIS IS ON PURPOSE AND BY DESIGN.  The background color feature
    // has typically been used with the 'classic' font to overwrite old
    // screen contents with new data.  This ONLY works because the
    // characters are a uniform size; it's not a sensible thing to do with
    // proportionally-spaced fonts with glyphs of varying sizes (and that
    // may overlap).  To replace previously-drawn text when using a custom
    // font, use the getTextBounds() function to determine the smallest
    // rectangle encompassing a string, erase the area with fillRect(),
    // then draw new text.  This WILL infortunately 'blink' the text, but
    // is unavoidable.  Drawing 'background' pixels will NOT fix this,
    // only creates a new set of problems.  Have an idea to work around
    // this (a canvas object type for MCUs that can afford the RAM and
    // displays supporting setAddrWindow() and pushColors()), but haven't
    // implemented this yet.

    startWrite();
    for (yy = 0; yy < h; yy++) {
      for (xx = 0; xx < w; xx++) {
        if (!(bit++ & 7)) {
          bits = pgm_read_byte(&bitmap[bo++]);
        }
        if (bits & 0x80) {
          if (size == 1) {
            writePixel(x + xo + xx, y + yo + yy, color);
          }
          else {
            writeFillRect(x + (xo16 + xx) * size, y + (yo16 + yy) * size, size,
                          size, color);
          }
        }
        bits <<= 1;
      }
    }
    endWrite();

  } // End classic vs custom font
}

#if ARDUINO >= 100
size_t Adafruit_GFX::write(uint8_t c)
{
#else
void Adafruit_GFX::write(uint8_t c)
{
#endif
  if (!gfxFont) { // 'Classic' built-in font

    if (c == '\n') {            // Newline?
      cursor_x = 0;             // Reset x to zero,
      cursor_y += textsize * 8; // advance y one line
    }
    else if (c != '\r') { // Ignore carriage returns
      if (wrap && ((cursor_x + textsize * 6) > _width)) { // Off right?
        cursor_x = 0;                                     // Reset x to zero,
        cursor_y += textsize * 8;                         // advance y one line
      }
      drawChar(cursor_x, cursor_y, c, textcolor, textbgcolor, textsize);
      cursor_x += textsize * 6; // Advance x one char
    }
  }
  else { // Custom font

    if (c == '\n') {
      cursor_x = 0;
      cursor_y +=
          (int16_t)textsize * (uint8_t)pgm_read_byte(&gfxFont->yAdvance);
    }
    else if (c != '\r') {
      uint8_t first = pgm_read_byte(&gfxFont->first);
      if ((c >= first) && (c <= (uint8_t)pgm_read_byte(&gfxFont->last))) {
        GFXglyph *glyph =
            &(((GFXglyph *)pgm_read_pointer(&gfxFont->glyph))[c - first]);
        uint8_t w = pgm_read_byte(&glyph->width),
                h = pgm_read_byte(&glyph->height);
        if ((w > 0) && (h > 0)) { // Is there an associated bitmap?
          int16_t xo = (int8_t)pgm_read_byte(&glyph->xOffset); // sic
          if (wrap && ((cursor_x + textsize * (xo + w)) > _width)) {
            cursor_x = 0;
            cursor_y +=
                (int16_t)textsize * (uint8_t)pgm_read_byte(&gfxFont->yAdvance);
          }
          drawChar(cursor_x, cursor_y, c, textcolor, textbgcolor, textsize);
        }
        cursor_x +=
            (uint8_t)pgm_read_byte(&glyph->xAdvance) * (int16_t)textsize;
      }
    }
  }
#if ARDUINO >= 100
  return 1;
#endif
}

void Adafruit_GFX::setCursor(int16_t x, int16_t y)
{
  cursor_x = x;
  cursor_y = y;
}

int16_t Adafruit_GFX::getCursorX(void) const { return cursor_x; }

int16_t Adafruit_GFX::getCursorY(void) const { return cursor_y; }

void Adafruit_GFX::setTextSize(uint8_t s) { textsize = (s > 0) ? s : 1; }

void Adafruit_GFX::setTextColor(uint16_t c)
{
  // For 'transparent' background, we'll set the bg
  // to the same as fg instead of using a flag
  textcolor = textbgcolor = c;
}

void Adafruit_GFX::setTextColor(uint16_t c, uint16_t b)
{
  textcolor = c;
  textbgcolor = b;
}

void Adafruit_GFX::setTextWrap(boolean w) { wrap = w; }

uint8_t Adafruit_GFX::getRotation(void) const { return rotation; }

void Adafruit_GFX::setRotation(uint8_t x)
{
  rotation = (x & 3);
  switch (rotation) {
  case 0:
  case 2:
    _width = WIDTH;
    _height = HEIGHT;
    break;
  case 1:
  case 3:
    _width = HEIGHT;
    _height = WIDTH;
    break;
  }
}

// Enable (or disable) Code Page 437-compatible charset.
// There was an error in glcdfont.c for the longest time -- one character
// (#176, the 'light shade' block) was missing -- this threw off the index
// of every character that followed it.  But a TON of code has been written
// with the erroneous character indices.  By default, the library uses the
// original 'wrong' behavior and old sketches will still work.  Pass 'true'
// to this function to use correct CP437 character values in your code.
void Adafruit_GFX::cp437(boolean x) { _cp437 = x; }

void Adafruit_GFX::setFont(const GFXfont *f)
{
  if (f) {          // Font struct pointer passed in?
    if (!gfxFont) { // And no current font struct?
      // Switching from classic to new font behavior.
      // Move cursor pos down 6 pixels so it's on baseline.
      cursor_y += 6;
    }
  }
  else if (gfxFont) { // NULL passed.  Current font struct defined?
    // Switching from new to classic font behavior.
    // Move cursor pos up 6 pixels so it's at top-left of char.
    cursor_y -= 6;
  }
  gfxFont = (GFXfont *)f;
}

// Broke this out as it's used by both the PROGMEM- and RAM-resident
// getTextBounds() functions.
void Adafruit_GFX::charBounds(char c, int16_t *x, int16_t *y, int16_t *minx,
                              int16_t *miny, int16_t *maxx, int16_t *maxy)
{

  if (gfxFont) {

    if (c == '\n') { // Newline?
      *x = 0;        // Reset x to zero, advance y by one line
      *y += textsize * (uint8_t)pgm_read_byte(&gfxFont->yAdvance);
    }
    else if (c != '\r') { // Not a carriage return; is normal char
      uint8_t first = pgm_read_byte(&gfxFont->first),
              last = pgm_read_byte(&gfxFont->last);
      if ((c >= first) && (c <= last)) { // Char present in this font?
        GFXglyph *glyph =
            &(((GFXglyph *)pgm_read_pointer(&gfxFont->glyph))[c - first]);
        uint8_t gw = pgm_read_byte(&glyph->width),
                gh = pgm_read_byte(&glyph->height),
                xa = pgm_read_byte(&glyph->xAdvance);
        int8_t xo = pgm_read_byte(&glyph->xOffset),
               yo = pgm_read_byte(&glyph->yOffset);
        if (wrap && ((*x + (((int16_t)xo + gw) * textsize)) > _width)) {
          *x = 0; // Reset x to zero, advance y by one line
          *y += textsize * (uint8_t)pgm_read_byte(&gfxFont->yAdvance);
        }
        int16_t ts = (int16_t)textsize, x1 = *x + xo * ts, y1 = *y + yo * ts,
                x2 = x1 + gw * ts - 1, y2 = y1 + gh * ts - 1;
        if (x1 < *minx)
          *minx = x1;
        if (y1 < *miny)
          *miny = y1;
        if (x2 > *maxx)
          *maxx = x2;
        if (y2 > *maxy)
          *maxy = y2;
        *x += xa * ts;
      }
    }
  }
  else { // Default font

    if (c == '\n') {      // Newline?
      *x = 0;             // Reset x to zero,
      *y += textsize * 8; // advance y one line
      // min/max x/y unchaged -- that waits for next 'normal' character
    }
    else if (c != '\r') { // Normal char; ignore carriage returns
      if (wrap && ((*x + textsize * 6) > _width)) { // Off right?
        *x = 0;                                     // Reset x to zero,
        *y += textsize * 8;                         // advance y one line
      }
      int x2 = *x + textsize * 6 - 1, // Lower-right pixel of char
          y2 = *y + textsize * 8 - 1;
      if (x2 > *maxx)
        *maxx = x2; // Track max x, y
      if (y2 > *maxy)
        *maxy = y2;
      if (*x < *minx)
        *minx = *x; // Track min x, y
      if (*y < *miny)
        *miny = *y;
      *x += textsize * 6; // Advance x one char
    }
  }
}

// Pass string and a cursor position, returns UL corner and W,H.
void Adafruit_GFX::getTextBounds(char *str, int16_t x, int16_t y, int16_t *x1,
                                 int16_t *y1, uint16_t *w, uint16_t *h)
{
  uint8_t c; // Current character

  *x1 = x;
  *y1 = y;
  *w = *h = 0;

  int16_t minx = _width, miny = _height, maxx = -1, maxy = -1;

  while ((c = *str++))
    charBounds(c, &x, &y, &minx, &miny, &maxx, &maxy);

  if (maxx >= minx) {
    *x1 = minx;
    *w = maxx - minx + 1;
  }
  if (maxy >= miny) {
    *y1 = miny;
    *h = maxy - miny + 1;
  }
}

// Return the size of the display (per current rotation)
int16_t Adafruit_GFX::width(void) const { return _width; }

int16_t Adafruit_GFX::height(void) const { return _height; }

void Adafruit_GFX::invertDisplay(boolean /*i*/)
{
  // Do nothing, must be subclassed if supported by hardware
}