TFT_eSPI/Extensions/Sprite.h

/***************************************************************************************
// The following class creates Sprites in RAM, graphics can then be drawn in the Sprite
// and rendered quickly onto the TFT screen. The class inherits the graphics functions
// from the TFT_eSPI class. Some functions are overridden by this class so that the
// graphics are written to the Sprite rather than the TFT.
***************************************************************************************/

class TFT_eSprite : public TFT_eSPI {

 public:

  explicit TFT_eSprite(TFT_eSPI *tft);
  ~TFT_eSprite(void);

           // Create a sprite of width x height pixels, return a pointer to the RAM area
           // Sketch can cast returned value to (uint16_t*) for 16-bit depth if needed
           // RAM required is:
           //  - 1 bit per pixel for 1 bit colour depth
           //  - 1 nibble per pixel for 4-bit colour (with palette table)
           //  - 1 byte per pixel for 8-bit colour (332 RGB format)
           //  - 2 bytes per pixel for 16-bit color depth (565 RGB format)
  void*    createSprite(int16_t width, int16_t height, uint8_t frames = 1);

           // Returns a pointer to the sprite or nullptr if not created, user must cast to pointer type
  void*    getPointer(void);

           // Returns true if sprite has been created
  bool     created(void);

           // Delete the sprite to free up the RAM
  void     deleteSprite(void);

           // Select the frame buffer for graphics write (for 2 colour ePaper and DMA toggle buffer)
           // Returns a pointer to the Sprite frame buffer
  void*    frameBuffer(int8_t f);
  
           // Set or get the colour depth to 1, 4, 8 or 16 bits. Can be used to change depth an existing
           // sprite, but clears it to black, returns a new pointer if sprite is re-created.
  void*    setColorDepth(int8_t b);
  int8_t   getColorDepth(void);

           // Set the palette for a 4-bit depth sprite.  Only the first 16 colours in the map are used.
  void     createPalette(uint16_t *palette = nullptr, uint8_t colors = 16);       // Palette in RAM
  void     createPalette(const uint16_t *palette = nullptr, uint8_t colors = 16); // Palette in FLASH

           // Set a single palette index to the given color
  void     setPaletteColor(uint8_t index, uint16_t color);

           // Get the color at the given palette index
  uint16_t getPaletteColor(uint8_t index);

           // Set foreground and background colours for 1 bit per pixel Sprite
  void     setBitmapColor(uint16_t fg, uint16_t bg);

           // Draw a single pixel at x,y
  void     drawPixel(int32_t x, int32_t y, uint32_t color);

           // Draw a single character in the GLCD or GFXFF font
  void     drawChar(int32_t x, int32_t y, uint16_t c, uint32_t color, uint32_t bg, uint8_t size),

           // Fill Sprite with a colour
           fillSprite(uint32_t color),

           // Define a window to push 16-bit colour pixels into in a raster order
           // Colours are converted to the set Sprite colour bit depth
           setWindow(int32_t x0, int32_t y0, int32_t x1, int32_t y1),
           // Push a color (aka singe pixel) to the sprite's set window area
           pushColor(uint16_t color),
           // Push len colors (pixels) to the sprite's set window area
           pushColor(uint16_t color, uint32_t len),
           // Push a pixel pre-formatted as a 1, 4, 8 or 16-bit colour (avoids conversion overhead)
           writeColor(uint16_t color),

           // Set the scroll zone, top left corner at x,y with defined width and height
           // The colour (optional, black is default) is used to fill the gap after the scroll
           setScrollRect(int32_t x, int32_t y, int32_t w, int32_t h, uint16_t color = TFT_BLACK),
           // Scroll the defined zone dx,dy pixels. Negative values left,up, positive right,down
           // dy is optional (default is 0, so no up/down scroll).
           // The sprite coordinate frame does not move because pixels are moved
           scroll(int16_t dx, int16_t dy = 0),

           // Draw lines
           drawLine(int32_t x0, int32_t y0, int32_t x1, int32_t y1, uint32_t color),
           drawFastVLine(int32_t x, int32_t y, int32_t h, uint32_t color),
           drawFastHLine(int32_t x, int32_t y, int32_t w, uint32_t color),

           // Fill a rectangular area with a color (aka draw a filled rectangle)
           fillRect(int32_t x, int32_t y, int32_t w, int32_t h, uint32_t color);

           // Set the coordinate rotation of the Sprite (for 1bpp Sprites only)
           // Note: this uses coordinate rotation and is primarily for ePaper which does not support
           // CGRAM rotation (like TFT drivers do) within the displays internal hardware
  void     setRotation(uint8_t rotation);
  uint8_t  getRotation(void);

           // Push a rotated copy of Sprite to TFT with optional transparent colour
  bool     pushRotated(int16_t angle, uint32_t transp = 0x00FFFFFF);
           // Push a rotated copy of Sprite to another different Sprite with optional transparent colour
  bool     pushRotated(TFT_eSprite *spr, int16_t angle, uint32_t transp = 0x00FFFFFF);

           // Get the TFT bounding box for a rotated copy of this Sprite
  bool     getRotatedBounds(int16_t angle, int16_t *min_x, int16_t *min_y, int16_t *max_x, int16_t *max_y);
           // Get the destination Sprite bounding box for a rotated copy of this Sprite
  bool     getRotatedBounds(TFT_eSprite *spr, int16_t angle, int16_t *min_x, int16_t *min_y,
                                                             int16_t *max_x, int16_t *max_y);
           // Bounding box support function
  void     getRotatedBounds(int16_t angle, int16_t w, int16_t h, int16_t xp, int16_t yp,
                            int16_t *min_x, int16_t *min_y, int16_t *max_x, int16_t *max_y);

           // Read the colour of a pixel at x,y and return value in 565 format 
  uint16_t readPixel(int32_t x0, int32_t y0);

           // return the numerical value of the pixel at x,y (used when scrolling)
           // 16bpp = colour, 8bpp = byte, 4bpp = colour index, 1bpp = 1 or 0
  uint16_t readPixelValue(int32_t x, int32_t y);

           // Write an image (colour bitmap) to the sprite.
  void     pushImage(int32_t x0, int32_t y0, int32_t w, int32_t h, uint16_t *data, uint8_t sbpp = 0);
  void     pushImage(int32_t x0, int32_t y0, int32_t w, int32_t h, const uint16_t *data);

           // Push the sprite to the TFT screen, this fn calls pushImage() in the TFT class.
           // Optionally a "transparent" colour can be defined, pixels of that colour will not be rendered
  void     pushSprite(int32_t x, int32_t y);
  void     pushSprite(int32_t x, int32_t y, uint16_t transparent);

           // Push a windowed area of the sprite to the TFT at tx, ty
  bool     pushSprite(int32_t tx, int32_t ty, int32_t sx, int32_t sy, int32_t sw, int32_t sh);

           // Push the sprite to another sprite at x,y. This fn calls pushImage() in the destination sprite (dspr) class.
  bool     pushToSprite(TFT_eSprite *dspr, int32_t x, int32_t y);
  bool     pushToSprite(TFT_eSprite *dspr, int32_t x, int32_t y, uint16_t transparent);

           // Draw a single character in the selected font
  int16_t  drawChar(uint16_t uniCode, int32_t x, int32_t y, uint8_t font),
           drawChar(uint16_t uniCode, int32_t x, int32_t y);

           // Return the width and height of the sprite
  int16_t  width(void),
           height(void);

           // Functions associated with anti-aliased fonts
           // Draw a single Unicode character using the loaded font
  void     drawGlyph(uint16_t code);
           // Print string to sprite using loaded font at cursor position
  void     printToSprite(String string);
           // Print char array to sprite using loaded font at cursor position
  void     printToSprite(char *cbuffer, uint16_t len);
           // Print indexed glyph to sprite using loaded font at x,y
  int16_t  printToSprite(int16_t x, int16_t y, uint16_t index);

 private:

  TFT_eSPI *_tft;

           // Reserve memory for the Sprite and return a pointer
  void*    callocSprite(int16_t width, int16_t height, uint8_t frames = 1);

           // Override the non-inlined TFT_eSPI functions
  void     begin_nin_write(void) { ; }
  void     end_nin_write(void) { ; }

 protected:

  uint8_t  _bpp;     // bits per pixel (1, 4, 8 or 16)
  uint16_t *_img;    // pointer to 16-bit sprite
  uint8_t  *_img8;   // pointer to  1 and 8-bit sprite frame 1 or frame 2
  uint8_t  *_img4;   // pointer to  4-bit sprite (uses color map)
  uint8_t  *_img8_1; // pointer to frame 1
  uint8_t  *_img8_2; // pointer to frame 2

  uint16_t *_colorMap; // color map pointer: 16 entries, used with 4-bit color map.

  int32_t  _sinra;   // Sine of rotation angle in fixed point
  int32_t  _cosra;   // Cosine of rotation angle in fixed point

  bool     _created; // A Sprite has been created and memory reserved
  bool     _gFont = false; 

  int32_t  _xs, _ys, _xe, _ye, _xptr, _yptr; // for setWindow
  int32_t  _sx, _sy; // x,y for scroll zone
  uint32_t _sw, _sh; // w,h for scroll zone
  uint32_t _scolor;  // gap fill colour for scroll zone

  int32_t  _iwidth, _iheight; // Sprite memory image bit width and height (swapped during rotations)
  int32_t  _dwidth, _dheight; // Real sprite width and height (for <8bpp Sprites)
  int32_t  _bitwidth;         // Sprite image bit width for drawPixel (for <8bpp Sprites, not swapped)

};