SSD1306Controller.cpp

/*
  Created by Fabrizio Di Vittorio (fdivitto2013@gmail.com) - <http://www.fabgl.com>
  Copyright (c) 2019-2022 Fabrizio Di Vittorio.
  All rights reserved.
 
 
* Please contact fdivitto2013@gmail.com if you need a commercial license.
 
 
* This library and related software is available under GPL v3.
 
  FabGL is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.
 
  FabGL is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.
 
  You should have received a copy of the GNU General Public License
  along with FabGL.  If not, see <http://www.gnu.org/licenses/>.
 */
 
 
#ifdef ARDUINO
 
 
#include <string.h>
 
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
 
#include "fabutils.h"
#include "SSD1306Controller.h"
 
 
#pragma GCC optimize ("O2")
 
 
#define SSD1306_I2C_TIMEOUT         100  // ms
#define SSD1306_I2C_FREQUENCY       400000
 
#define SSD1306_UPDATETASK_STACK    1024
#define SSD1306_UPDATETASK_PRIORITY 5
 
#define SSD1306_BACKGROUND_PRIMITIVE_TIMEOUT 10000  // uS
 
 
#define SSD1306_SETLOWCOLUMN                         0x00
#define SSD1306_SETHIGHCOLUMN                        0x10
#define SSD1306_MEMORYMODE                           0x20
#define SSD1306_COLUMNADDR                           0x21
#define SSD1306_PAGEADDR                             0x22
#define SSD1306_RIGHT_HORIZONTAL_SCROLL              0x26
#define SSD1306_LEFT_HORIZONTAL_SCROLL               0x27
#define SSD1306_VERTICAL_AND_RIGHT_HORIZONTAL_SCROLL 0x29
#define SSD1306_VERTICAL_AND_LEFT_HORIZONTAL_SCROLL  0x2A
#define SSD1306_DEACTIVATE_SCROLL                    0x2E
#define SSD1306_ACTIVATE_SCROLL                      0x2F
#define SSD1306_SETSTARTLINE                         0x40
#define SSD1306_SETCONTRAST                          0x81
#define SSD1306_CHARGEPUMP                           0x8D
#define SSD1306_SEGREMAP                             0xA0
#define SSD1306_SET_VERTICAL_SCROLL_AREA             0xA3
#define SSD1306_DISPLAYALLON_RESUME                  0xA4
#define SSD1306_DISPLAYALLON                         0xA5
#define SSD1306_NORMALDISPLAY                        0xA6
#define SSD1306_INVERTDISPLAY                        0xA7
#define SSD1306_SETMULTIPLEX                         0xA8
#define SSD1306_DISPLAYOFF                           0xAE
#define SSD1306_DISPLAYON                            0xAF
#define SSD1306_COMSCANINC                           0xC0
#define SSD1306_COMSCANDEC                           0xC8
#define SSD1306_SETDISPLAYOFFSET                     0xD3
#define SSD1306_SETDISPLAYCLOCKDIV                   0xD5
#define SSD1306_SETPRECHARGE                         0xD9
#define SSD1306_SETCOMPINS                           0xDA
#define SSD1306_SETVCOMDETECT                        0xDB
 
 
#define SSD1306_SETPIXEL(x, y)              (m_screenBuffer[(x) + ((y) >> 3) * m_viewPortWidth] |=  (1 << ((y) & 7)))
#define SSD1306_CLEARPIXEL(x, y)            (m_screenBuffer[(x) + ((y) >> 3) * m_viewPortWidth] &= ~(1 << ((y) & 7)))
#define SSD1306_INVERTPIXEL(x, y)           (m_screenBuffer[(x) + ((y) >> 3) * m_viewPortWidth] ^=  (1 << ((y) & 7)))
 
#define SSD1306_SETPIXELCOLOR(x, y, color)  { if ((color)) SSD1306_SETPIXEL((x), (y)); else SSD1306_CLEARPIXEL((x), (y)); }
 
#define SSD1306_GETPIXEL(x, y)              ((m_screenBuffer[(x) + ((y) >> 3) * m_viewPortWidth] >> ((y) & 7)) & 1)
 
 
namespace fabgl {
 
 
inline uint8_t RGB888toMono(RGB888 const & rgb)
{
  return rgb.R > 0 || rgb.G > 0 || rgb.B > 0 ? 1 : 0;
}
 
 
inline uint8_t RGBA2222toMono(uint8_t rgba2222)
{
  return (rgba2222 & 0x3f) ? 1 : 0;
}
 
 
inline uint8_t RGBA8888toMono(RGBA8888 const & rgba)
{
  return rgba.R > 0 || rgba.G > 0 || rgba.B > 0 ? 1 : 0;
}
 
 
inline uint8_t preparePixel(RGB888 const & rgb)
{
  return RGB888toMono(rgb);
}
 
 
 
SSD1306Controller::SSD1306Controller()
  : m_i2c(nullptr),
    m_screenBuffer(nullptr),
    m_updateTaskHandle(nullptr),
    m_updateTaskRunning(false),
    m_orientation(SSD1306Orientation::Normal)
{
}
 
 
SSD1306Controller::~SSD1306Controller()
{
  end();
}
 
 
void SSD1306Controller::begin(I2C * i2c, int address, gpio_num_t resetGPIO)
{
  CurrentVideoMode::set(VideoMode::I2C);
  m_i2c        = i2c;
  m_i2cAddress = address;
  m_resetGPIO  = resetGPIO;
}
 
 
void SSD1306Controller::begin()
{
  auto i2c = new I2C;
  i2c->begin(GPIO_NUM_4, GPIO_NUM_15);
  begin(i2c);
}
 
 
void SSD1306Controller::end()
{
  if (m_updateTaskHandle)
    vTaskDelete(m_updateTaskHandle);
  m_updateTaskHandle = nullptr;
 
  free(m_screenBuffer);
  m_screenBuffer = nullptr;
}
 
 
void SSD1306Controller::setResolution(char const * modeline, int viewPortWidth, int viewPortHeight, bool doubleBuffered)
{
  char label[32];
  int pos = 0, swidth, sheight;
  int count = sscanf(modeline, "\"%[^\"]\" %d %d %n", label, &swidth, &sheight, &pos);
  if (count != 3 || pos == 0)
    return; // invalid modeline
 
  m_screenWidth  = swidth;
  m_screenHeight = sheight;
  m_screenCol    = 0;
  m_screenRow    = 0;
 
  // inform base class about screen size
  setScreenSize(m_screenWidth, m_screenHeight);
 
  setDoubleBuffered(doubleBuffered);
 
  m_viewPortWidth  = viewPortWidth < 0 ? m_screenWidth : viewPortWidth;
  m_viewPortHeight = viewPortHeight < 0 ? m_screenHeight : viewPortHeight;
 
  resetPaintState();
 
  SSD1306_hardReset();
 
  if (!SSD1306_softReset())
    return;
 
  allocScreenBuffer();
 
  // setup update task
  xTaskCreate(&updateTaskFunc, "", SSD1306_UPDATETASK_STACK, this, SSD1306_UPDATETASK_PRIORITY, &m_updateTaskHandle);
 
  // allows updateTaskFunc() to run
  m_updateTaskFuncSuspended = 0;
}
 
 
void SSD1306Controller::setScreenCol(int value)
{
  if (value != m_screenCol) {
    m_screenCol = iclamp(value, 0, m_viewPortWidth - m_screenWidth);
    sendRefresh();
  }
}
 
 
void SSD1306Controller::setScreenRow(int value)
{
  if (value != m_screenRow) {
    m_screenRow = iclamp(value, 0, m_viewPortHeight - m_screenHeight);
    sendRefresh();
  }
}
 
 
void SSD1306Controller::sendRefresh()
{
  Primitive p(PrimitiveCmd::Refresh, Rect(0, 0, m_viewPortWidth - 1, m_viewPortHeight - 1));
  addPrimitive(p);
}
 
 
bool SSD1306Controller::SSD1306_sendData(uint8_t * buf, int count, uint8_t ctrl)
{
  int bufSize = m_i2c->getMaxBufferLength();
  uint8_t sbuf[bufSize];
  sbuf[0] = ctrl;
  while (count > 0) {
    int bToSend = imin(bufSize - 1, count);
    memcpy(&sbuf[1], buf, bToSend);
    if (!m_i2c->write(m_i2cAddress, sbuf, bToSend + 1, SSD1306_I2C_FREQUENCY, SSD1306_I2C_TIMEOUT))
      return false;
    count -= bToSend;
    buf   += bToSend;
    ets_delay_us(2);  // delay 2uS (standing to SSD1306 doc should be 1.3uS, before new transmission can start)
  }
  return true;
}
 
 
bool SSD1306Controller::SSD1306_sendCmd(uint8_t c)
{
  return SSD1306_sendData(&c, 1, 0x00);
}
 
 
bool SSD1306Controller::SSD1306_sendCmd(uint8_t c1, uint8_t c2)
{
  uint8_t buf[2] = { c1, c2 };
  return SSD1306_sendData(buf, 2, 0x00);
}
 
 
bool SSD1306Controller::SSD1306_sendCmd(uint8_t c1, uint8_t c2, uint8_t c3)
{
  uint8_t buf[3] = { c1, c2, c3 };
  return SSD1306_sendData(buf, 3, 0x00);
}
 
 
// hard reset SSD1306
void SSD1306Controller::SSD1306_hardReset()
{
  if (m_resetGPIO != GPIO_UNUSED) {
    configureGPIO(m_resetGPIO, GPIO_MODE_OUTPUT);
    gpio_set_level(m_resetGPIO, 1);
    vTaskDelay(1 / portTICK_PERIOD_MS);
    gpio_set_level(m_resetGPIO, 0);
    vTaskDelay(10 / portTICK_PERIOD_MS);
    gpio_set_level(m_resetGPIO, 1);
  }
}
 
 
// soft reset SSD1306
bool SSD1306Controller::SSD1306_softReset()
{
  SSD1306_sendCmd(SSD1306_DISPLAYOFF);
  SSD1306_sendCmd(SSD1306_SETDISPLAYCLOCKDIV, 0x80);
  SSD1306_sendCmd(SSD1306_SETMULTIPLEX, m_screenHeight - 1);
  SSD1306_sendCmd(SSD1306_SETDISPLAYOFFSET, 0);
  SSD1306_sendCmd(SSD1306_SETSTARTLINE);
  SSD1306_sendCmd(SSD1306_CHARGEPUMP, 0x14);      // 0x14 = SWITCHCAPVCC,  0x10 = EXTERNALVCC
  SSD1306_sendCmd(SSD1306_MEMORYMODE, 0b100);     // 0b100 = page addressing mode
  setupOrientation();
  if (m_screenHeight == 64) {
    SSD1306_sendCmd(SSD1306_SETCOMPINS, 0x12);
    SSD1306_sendCmd(SSD1306_SETCONTRAST, 0xCF);   // max: 0xCF = SWITCHCAPVCC,  0x9F = EXTERNALVCC
  } else if (m_screenHeight == 32) {
    SSD1306_sendCmd(SSD1306_SETCOMPINS, 0x02);
    SSD1306_sendCmd(SSD1306_SETCONTRAST, 0x8F);
  }
  SSD1306_sendCmd(SSD1306_SETPRECHARGE, 0xF1);    // 0xF1 = SWITCHCAPVCC,  0x22 = EXTERNALVCC
  SSD1306_sendCmd(SSD1306_SETVCOMDETECT, 0x40);
  SSD1306_sendCmd(SSD1306_DISPLAYALLON_RESUME);
  SSD1306_sendCmd(SSD1306_NORMALDISPLAY);
  SSD1306_sendCmd(SSD1306_DEACTIVATE_SCROLL);
  return SSD1306_sendCmd(SSD1306_DISPLAYON);
}
 
 
void SSD1306Controller::setupOrientation()
{
  switch (m_orientation) {
    case SSD1306Orientation::Normal:
      SSD1306_sendCmd(SSD1306_SEGREMAP | 0x1);
      SSD1306_sendCmd(SSD1306_COMSCANDEC);
      break;
    case SSD1306Orientation::ReverseHorizontal:
      SSD1306_sendCmd(SSD1306_SEGREMAP | 0x0);
      SSD1306_sendCmd(SSD1306_COMSCANDEC);
      break;
    case SSD1306Orientation::ReverseVertical:
      SSD1306_sendCmd(SSD1306_SEGREMAP | 0x1);
      SSD1306_sendCmd(SSD1306_COMSCANINC);
      break;
    case SSD1306Orientation::Rotate180:
      SSD1306_sendCmd(SSD1306_SEGREMAP | 0x0);
      SSD1306_sendCmd(SSD1306_COMSCANINC);
      break;
  }
}
 
 
void SSD1306Controller::setOrientation(SSD1306Orientation value)
{
  m_orientation = value;
  setupOrientation();
  sendRefresh();
}
 
 
void SSD1306Controller::SSD1306_sendScreenBuffer(Rect updateRect)
{
  // align visible screen row to page (steps of 8 rows)
  const int screenRow = m_screenRow & ~7;
 
  // visible area
  const Rect scrRect = Rect(m_screenCol, screenRow, m_screenCol + m_screenWidth - 1, screenRow + m_screenHeight - 1);
 
  // align rectangle to update to pages (0, 8, 16...)
  updateRect.Y1 &= ~7;
  updateRect.Y2  = (updateRect.Y2 + 7) & ~7;
 
  // does the visible area intersect with area to update?
  if (scrRect.intersects(updateRect)) {
 
    // intersection between visible area and rectangle to update
    Rect r = updateRect.intersection(scrRect);
 
    // horizontal screen update limits
    const int screenX1 = r.X1 - m_screenCol;
    const int screenX2 = r.X2 - m_screenCol;
 
    // send one page (8 rows) at the time
    for (int y = r.Y1; y <= r.Y2; y += 8) {
      int screenY = y - screenRow;
      if (screenY >= 0) {
        int page = screenY >> 3;
        if (!(SSD1306_sendCmd(SSD1306_PAGEADDR, page, page) && SSD1306_sendCmd(SSD1306_COLUMNADDR, screenX1, screenX2)))
          break;  // address selection failed, try with next page
        SSD1306_sendData(m_screenBuffer + r.X1 + (y >> 3) * m_viewPortWidth, r.width(), 0x40);
      }
    }
 
  }
}
 
 
void SSD1306Controller::invert(bool value)
{
  SSD1306_sendCmd(value ? SSD1306_INVERTDISPLAY : SSD1306_NORMALDISPLAY);
}
 
 
void SSD1306Controller::allocScreenBuffer()
{
  m_screenBuffer = (uint8_t*) malloc(m_viewPortWidth * m_viewPortHeight / 8);
  memset(m_screenBuffer, 0, m_viewPortWidth * m_viewPortHeight / 8);
}
 
 
void SSD1306Controller::updateTaskFunc(void * pvParameters)
{
  SSD1306Controller * ctrl = (SSD1306Controller*) pvParameters;
 
  while (true) {
 
    ctrl->waitForPrimitives();
 
    // primitive processing blocked?
    if (ctrl->m_updateTaskFuncSuspended > 0)
      ulTaskNotifyTake(true, portMAX_DELAY); // yes, wait for a notify
 
    ctrl->m_updateTaskRunning = true;
 
    Rect updateRect = Rect(SHRT_MAX, SHRT_MAX, SHRT_MIN, SHRT_MIN);
 
    int64_t startTime = ctrl->backgroundPrimitiveTimeoutEnabled() ? esp_timer_get_time() : 0;
    do {
 
      Primitive prim;
      if (ctrl->getPrimitive(&prim) == false)
        break;
 
      ctrl->execPrimitive(prim, updateRect, false);
 
      if (ctrl->m_updateTaskFuncSuspended > 0)
        break;
 
    } while (!ctrl->backgroundPrimitiveTimeoutEnabled() || (startTime + SSD1306_BACKGROUND_PRIMITIVE_TIMEOUT > esp_timer_get_time()));
 
    ctrl->showSprites(updateRect);
 
    ctrl->m_updateTaskRunning = false;
 
    if (!ctrl->isDoubleBuffered())
      ctrl->SSD1306_sendScreenBuffer(updateRect);
  }
}
 
 
 
void SSD1306Controller::suspendBackgroundPrimitiveExecution()
{
  ++m_updateTaskFuncSuspended;
  while (m_updateTaskRunning)
    taskYIELD();
}
 
 
void SSD1306Controller::resumeBackgroundPrimitiveExecution()
{
  m_updateTaskFuncSuspended = tmax(0, m_updateTaskFuncSuspended - 1);
  if (m_updateTaskFuncSuspended == 0)
    xTaskNotifyGive(m_updateTaskHandle);  // resume updateTaskFunc()
}
 
 
void SSD1306Controller::setPixelAt(PixelDesc const & pixelDesc, Rect & updateRect)
{
  genericSetPixelAt(pixelDesc, updateRect,
                    [&] (RGB888 const & color)          { return preparePixel(color); },
                    [&] (int X, int Y, uint8_t pattern) { SSD1306_SETPIXELCOLOR(X, Y, pattern); }
                   );
}
 
 
// coordinates are absolute values (not relative to origin)
// line clipped on current absolute clipping rectangle
void SSD1306Controller::absDrawLine(int X1, int Y1, int X2, int Y2, RGB888 color)
{
  genericAbsDrawLine(X1, Y1, X2, Y2, color,
                     [&] (RGB888 const & color)                   { return preparePixel(color); },
                     [&] (int Y, int X1, int X2, uint8_t pattern) { rawFillRow(Y, X1, X2, pattern); },
                     [&] (int Y, int X1, int X2)                  { rawInvertRow(Y, X1, X2); },
                     [&] (int X, int Y, uint8_t pattern)          { SSD1306_SETPIXELCOLOR(X, Y, pattern); },
                     [&] (int X, int Y)                           { SSD1306_INVERTPIXEL(X, Y); }
                     );
}
 
 
// parameters not checked
void SSD1306Controller::rawFillRow(int y, int x1, int x2, uint8_t pattern)
{
  if (pattern) {
    for (; x1 <= x2; ++x1)
      SSD1306_SETPIXEL(x1, y);
  } else {
    for (; x1 <= x2; ++x1)
      SSD1306_CLEARPIXEL(x1, y);
  }
}
 
 
// parameters not checked
void SSD1306Controller::rawFillRow(int y, int x1, int x2, RGB888 color)
{
  rawFillRow(y, x1, x2, preparePixel(color));
}
 
 
// parameters not checked
void SSD1306Controller::rawInvertRow(int y, int x1, int x2)
{
  for (; x1 <= x2; ++x1)
    SSD1306_INVERTPIXEL(x1, y);
}
 
 
void SSD1306Controller::drawEllipse(Size const & size, Rect & updateRect)
{
  genericDrawEllipse(size, updateRect,
                     [&] (RGB888 const & color)          { return preparePixel(color); },
                     [&] (int X, int Y, uint8_t pattern) { SSD1306_SETPIXELCOLOR(X, Y, pattern); }
                    );
}
 
 
void SSD1306Controller::clear(Rect & updateRect)
{
  hideSprites(updateRect);
  uint8_t pattern = preparePixel(getActualBrushColor());
  memset(m_screenBuffer, (pattern ? 255 : 0), m_viewPortWidth * m_viewPortHeight / 8);
}
 
 
void SSD1306Controller::VScroll(int scroll, Rect & updateRect)
{
  genericVScroll(scroll, updateRect,
                 [&] (int x1, int x2, int srcY, int dstY)  { rawCopyRow(x1, x2, srcY, dstY); }, // rawCopyRow
                 [&] (int y, int x1, int x2, RGB888 color) { rawFillRow(y, x1, x2, color);   }  // rawFillRow
                );
}
 
 
void SSD1306Controller::HScroll(int scroll, Rect & updateRect)
{
  genericHScroll(scroll, updateRect,
                 [&] (RGB888 const & color)      { return preparePixel(color); },           // preparePixel
                 [&] (int y)                     { return y; },                             // rawGetRow
                 [&] (int y, int x)              { return SSD1306_GETPIXEL(x, y); },        // rawGetPixelInRow
                 [&] (int y, int x, int pattern) { SSD1306_SETPIXELCOLOR(x, y, pattern); }  // rawSetPixelInRow
                );
}
 
 
void SSD1306Controller::drawGlyph(Glyph const & glyph, GlyphOptions glyphOptions, RGB888 penColor, RGB888 brushColor, Rect & updateRect)
{
  genericDrawGlyph(glyph, glyphOptions, penColor, brushColor, updateRect,
                   [&] (RGB888 const & color)          { return preparePixel(color); },
                   [&] (int y)                         { return y; },
                   [&] (int y, int x, uint8_t pattern) { SSD1306_SETPIXELCOLOR(x, y, pattern); }
                  );
}
 
 
void SSD1306Controller::rawCopyRow(int x1, int x2, int srcY, int dstY)
{
  for (; x1 <= x2; ++x1) {
    uint8_t c = SSD1306_GETPIXEL(x1, srcY);
    SSD1306_SETPIXELCOLOR(x1, dstY, c);
  }
}
 
 
void SSD1306Controller::invertRect(Rect const & rect, Rect & updateRect)
{
  genericInvertRect(rect, updateRect,
                    [&] (int Y, int X1, int X2) { rawInvertRow(Y, X1, X2); }
                   );
}
 
 
void SSD1306Controller::swapFGBG(Rect const & rect, Rect & updateRect)
{
  invertRect(rect, updateRect);
}
 
 
// supports overlapping of source and dest rectangles
void SSD1306Controller::copyRect(Rect const & source, Rect & updateRect)
{
  genericCopyRect(source, updateRect,
                  [&] (int y)                         { return y; },
                  [&] (int y, int x)                  { return SSD1306_GETPIXEL(x, y); },
                  [&] (int y, int x, uint8_t pattern) { SSD1306_SETPIXELCOLOR(x, y, pattern); }
                 );
}
 
 
// no bounds check is done!
void SSD1306Controller::readScreen(Rect const & rect, RGB888 * destBuf)
{
  for (int y = rect.Y1; y <= rect.Y2; ++y)
    for (int x = rect.X1; x <= rect.X2; ++x, ++destBuf)
      *destBuf = SSD1306_GETPIXEL(x, y) ? RGB888(255, 255, 255) : RGB888(0, 0, 0);
}
 
 
void SSD1306Controller::rawDrawBitmap_Native(int destX, int destY, Bitmap const * bitmap, int X1, int Y1, int XCount, int YCount)
{
  genericRawDrawBitmap_Native(destX, destY, (uint8_t*) bitmap->data, bitmap->width, X1, Y1, XCount, YCount,
                                [&] (int y)                     { return y; },                         // rawGetRow
                                [&] (int y, int x, uint8_t src) { SSD1306_SETPIXELCOLOR(x, y, src); }  // rawSetPixelInRow
                               );
}
 
 
void SSD1306Controller::rawDrawBitmap_Mask(int destX, int destY, Bitmap const * bitmap, void * saveBackground, int X1, int Y1, int XCount, int YCount)
{
  uint8_t foregroundColor = RGB888toMono(bitmap->foregroundColor);
  genericRawDrawBitmap_Mask(destX, destY, bitmap, (uint8_t*)saveBackground, X1, Y1, XCount, YCount,
                            [&] (int y)        { return y; },                                     // rawGetRow
                            [&] (int y, int x) { return SSD1306_GETPIXEL(x, y); },                // rawGetPixelInRow
                            [&] (int y, int x) { SSD1306_SETPIXELCOLOR(x, y, foregroundColor); }  // rawSetPixelInRow
                           );
}
 
 
void SSD1306Controller::rawDrawBitmap_RGBA2222(int destX, int destY, Bitmap const * bitmap, void * saveBackground, int X1, int Y1, int XCount, int YCount)
{
  genericRawDrawBitmap_RGBA2222(destX, destY, bitmap, (uint8_t*)saveBackground, X1, Y1, XCount, YCount,
                                [&] (int y)                     { return y; },                                         // rawGetRow
                                [&] (int y, int x)              { return SSD1306_GETPIXEL(x, y); },                    // rawGetPixelInRow
                                [&] (int y, int x, uint8_t src) { SSD1306_SETPIXELCOLOR(x, y, RGBA2222toMono(src)); }  // rawSetPixelInRow
                               );
}
 
 
void SSD1306Controller::rawDrawBitmap_RGBA8888(int destX, int destY, Bitmap const * bitmap, void * saveBackground, int X1, int Y1, int XCount, int YCount)
{
  genericRawDrawBitmap_RGBA8888(destX, destY, bitmap, (uint8_t*)saveBackground, X1, Y1, XCount, YCount,
                                [&] (int y)                              { return y; },                                         // rawGetRow
                                [&] (int y, int x)                       { return SSD1306_GETPIXEL(x, y); },                    // rawGetPixelInRow
                                [&] (int y, int x, RGBA8888 const & src) { SSD1306_SETPIXELCOLOR(x, y, RGBA8888toMono(src)); }  // rawSetPixelInRow
                               );
}
 
 
void SSD1306Controller::swapBuffers()
{
  // nothing to do, we just send current view port to the device
  SSD1306_sendScreenBuffer(Rect(0, 0, getViewPortWidth() - 1, getViewPortHeight() - 1));
}
 
 
 
 
} // end of namespace
 
 
 
#endif // #ifdef ARDUINO