Pixels.h

/*
    Pixels. Graphics library for TFT displays.

    Copyright (C) 2012-2013  Igor Repinetski

    The code is written in C/C++ for Arduino and can be easily ported to any microcontroller by rewritting the low level pin access functions.

    Text output methods of the library rely on Pixelmeister's font data format. See: http://pd4ml.com/pixelmeister

    This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-sa/3.0/

    Commercial use of the library is possible for licensees of "Pixelmeister (for industry)" product.

    This library includes some code portions and algoritmic ideas derived from works of
    - Andreas Schiffler -- aschiffler at ferzkopp dot net (SDL_gfx Project)
    - K. Townsend http://microBuilder.eu (lpc1343codebase Project)
    - CMBSolutions git()cmbsolutions.nl
*/

/*
    Currently supported platforms:

    1. Reference platform: Arduino Mega, TFT_PQ 2.4 (ILI9325 controller), ITDB02 MEGA Shield v1.1

    More platforms coming soon
*/

#ifndef PIXELS_BASE_H
#define PIXELS_BASE_H

// #define DISABLE_ANTIALIASING 1

//#if defined(__arm__)
//#include <avr/dtostrf.h>
//#endif

#if defined(__AVR__) || defined(TEENSYDUINO) || defined(GLOWDECK)
#include <Arduino.h>

#define regtype volatile uint8_t
#define regsize uint8_t

#define cbi(reg, bitmask) *reg &= ~bitmask
#define sbi(reg, bitmask) *reg |= bitmask
#define pulse_high(reg, bitmask) sbi(reg, bitmask); cbi(reg, bitmask);
#define pulse_low(reg, bitmask) cbi(reg, bitmask); sbi(reg, bitmask);
//#define prog_uchar const unsigned char
//#define prog_uint16_t const uint16_t

#elif defined(__SAM3X8E__)
#include <Arduino.h>
#define PROGMEM

#define prog_uchar const unsigned char
#define prog_uint16_t const uint16_t

#define pgm_read_byte(x)        (*((char *)x))
#define pgm_read_word(x)        ( ((*((unsigned char *)x + 1)) << 8) + (*((unsigned char *)x)))
#define pgm_read_byte_near(x)   (*((char *)x))
#define pgm_read_byte_far(x)    (*((char *)x))
//  #define pgm_read_word(x)        (*((short *)(x & 0xfffffffe)))
//  #define pgm_read_word_near(x)   (*((short *)(x & 0xfffffffe))
//  #define pgm_read_word_far(x)    (*((short *)(x & 0xfffffffe)))
#define pgm_read_word_near(x)   ( ((*((unsigned char *)x + 1)) << 8) + (*((unsigned char *)x)))
#define pgm_read_word_far(x)    ( ((*((unsigned char *)x + 1)) << 8) + (*((unsigned char *)x))))
#define PSTR(x)  x

#define cbi(reg, bitmask) *reg &= ~bitmask
#define sbi(reg, bitmask) *reg |= bitmask
#define pulse_high(reg, bitmask) sbi(reg, bitmask); cbi(reg, bitmask);
#define pulse_low(reg, bitmask) cbi(reg, bitmask); sbi(reg, bitmask);

#define cport(port, data) port &= data
#define sport(port, data) port |= data

#define regtype volatile uint32_t
#define regsize uint32_t

#else
#define PROGMEM

#ifndef prog_uchar
#define prog_uchar byte
#define prog_uint16_t const uint16_t
#endif

#define regtype volatile uint32_t
#define regsize uint16_t
#endif

#define swap(a, b) {int16_t buf = a; a = b; b = buf;}

#define BITMASK_FONT 1
#define ANTIALIASED_FONT 2
#define HEADER_LENGTH 5

#define SCROLL_SMOOTH 1
#define SCROLL_CLEAN 2

#define FILL_TOPDOWN 0
#define FILL_LEFTRIGHT 0
#define FILL_DOWNTOP 1
#define FILL_RIGHTLEFT 2

#define ORIGIN_RELATIVE true // origin relative to a current scroll position
#define ORIGIN_ABSOLUTE false // origin matches physical device pixel coordinates

#define PORTRAIT 0
#define LANDSCAPE 1
#define PORTRAIT_FLIP 2
#define LANDSCAPE_FLIP 3

#define ipart(X) ((int16_t)(X))
// #define round(X) ((uint16_t)(((double)(X))+0.5))
#define fpart(X) (((double)(X))-(double)ipart(X))
#define rfpart(X) (1.0-fpart(X))

extern regtype *registerCS; // chip select
extern regsize bitmaskCS;

#define chipSelect() cbi(registerCS, bitmaskCS)
#define chipDeselect() sbi(registerCS, bitmaskCS)

class PRGB
{
  public:
    uint8_t red;
    uint8_t green;
    uint8_t blue;

    PRGB(uint8_t r, uint8_t g, uint8_t b);
    PRGB();

    PRGB convert565toRGB(uint16_t color);
    uint16_t convertRGBto565(PRGB color);
    uint16_t convertTo565();
};

class PixelsBase
{
  protected:
    /* device physical dimension in portrait orientation */
    int16_t deviceWidth;
    int16_t deviceHeight;

    /* device logical dimension in current orientation */
    int16_t width;
    int16_t height;

    boolean landscape;

    uint8_t orientation;

    boolean relativeOrigin;

    /* currently selected font */
    prog_uchar* currentFont;

    PRGB* foreground;
    PRGB* background;

    double lineWidth;

    uint8_t fillDirection;
    boolean antialiasing;

    boolean scrollSupported;
    boolean scrollEnabled;

    int16_t currentScroll;
    int16_t flipScroll;
    boolean scrollCleanMode;

    void printString(int16_t xx, int16_t yy, String text, boolean clean, int8_t kerning[] = NULL);
    void drawGlyph(int16_t fontType, boolean clean, int16_t xx, int16_t yy,
                   int16_t height, prog_uchar* data, int16_t ptr, int16_t length);

    virtual void setRegion(int16_t x1, int16_t y1, int16_t x2, int16_t y2) {};
    void setCurrentPixel(PRGB* color);
    void setCurrentPixel(int16_t color);
    void fill(int b, int16_t x1, int16_t y1, int16_t x2, int16_t y2);
    virtual void quickFill(int b, int16_t x1, int16_t y1, int16_t x2, int16_t y2) {};
    void putColor(int16_t x, int16_t y, boolean steep, double weight);
    PRGB* computeColor(PRGB* bg, double weight);
    PRGB* computeColor(PRGB* fg, uint8_t opacity);

    void resetRegion();

    void hLine(int16_t x1, int16_t y1, int16_t x2);
    void vLine(int16_t x1, int16_t y1, int16_t y2);

    virtual void deviceWriteData(uint8_t hi, uint8_t lo) {};

    virtual void scrollCmd() {};

    virtual void drawCircleAntialiaced(int16_t x, int16_t y, int16_t radius, boolean bordermode);
    virtual void drawFatLineAntialiased(int16_t x1, int16_t y1, int16_t x2, int16_t y2);
    virtual void drawLineAntialiased(int16_t x1, int16_t y1, int16_t x2, int16_t y2);
    virtual void drawRoundRectangleAntialiased(int16_t x, int16_t y, int16_t width, int16_t height, int16_t rx, int16_t ry, boolean bordermode);

    int16_t* loadFileBytes(String);

    PRGB* computedBgColor;
    PRGB* computedFgColor;
    PRGB* bgBuffer;
    PRGB* fgBuffer;

  public:
    /**
        Constructs a new <code>Pixels</code> object for the reference platform TFT_PQ 2.4 (ILI9325 controller) + ITDB02 MEGA Shield v1.1.
        @param width target device width (in pixels)
        @param height target device height (in pixels)
    */
    PixelsBase(uint16_t width, uint16_t height);
    /**
        Initializes hardware with defaults.
    */
    virtual void init() {};
    /**
        Sets the current coordinate space orientation.
        Default value depends on initially given device width and height (PORTRAIT if height > width, otherwise LANDSCAPE).
        @param orientation accepts PORTRAIT, LANDSCAPE, PORTRAIT_FLIP or LANDSCAPE_FLIP
    */
    void setOrientation(uint8_t orientation);
    /**
        Returns the current coordinate space orientation.
        @return the current orientation
        @see setOrientation(uint8_t)
    */
    inline uint8_t getOrientation() {
        return orientation;
    }
    /**
        Enables or disables antialiasing by a drawing of graphical primitives. The metod does not impact antialiased fonts.
        Antialiased output in general requires more resources/time to output comparing to "grainy" output mode.
        Takes no effect if Pixels_Antialiasing.h is not included
        @param enable a boolean value that determines whether the antialiasing should be enabled or not
    */
    virtual void enableAntialiasing(boolean enable) {
        antialiasing = false;
    }

    /**
        Gets the current antialiasing mode.
        @return a boolean value that shows whether the antialiasing is be enabled or not
    */
    inline boolean isAntialiased() {
        return antialiasing;
    }
    /**
        Enables or disables scroll feature.
        @param enable a boolean value that determines whether the scroll feature should be enabled or not
        @see scroll(int16_t,int8_t)
    */
    inline void enableScroll(boolean enable) {
        scrollEnabled = enable;
    }
    /**
        @returns <i>true</i> if the target device can scroll and the scroll feature is enabled.
        @see scroll(int16_t,int8_t)
        @see enableScroll(boolean)
    */
    inline boolean canScroll() {
        return scrollEnabled & scrollSupported;
    }
    /**
        Sets the current line width. For time being the line width is respected by
        drawLine(int16_t,int16_t,int16_t,int16_t) and a line width control is still "under construction".
        @param width new line width.
    */
    inline void setLineWidth(double width) {
        lineWidth = width;
    }
    /**
        Returns the current line width.
        @return the current line width.
    */
    inline double getLineWidth() {
        return lineWidth;
    }
    /**
        Returns device width.
        @return device width.
    */
    inline int16_t getWidth() {
        return width;
    }
    /**
        Returns device height.
        @return device height.
    */
    inline int16_t getHeight() {
        return height;
    }
    /**
        Bounds the coordinate space to the device controller video RAM. The physical output depends on the actual scroll position.
    */
    inline void setOriginRelative() {
        relativeOrigin = true;
    }
    /**
        Bounds the coordinate space to physical device pixels, ignoring actual scroll position.
        @see scroll(int16_t,int8_t)
    */
    inline void setOriginAbsolute() {
        relativeOrigin = false;
    }
    /**
        @return <i>true</i> if the current positioning is relative.
        @see setOriginRelative()
        @see setOriginAbsolute()
    */
    inline boolean isOriginRelative() {
        return relativeOrigin;
    }
    /**
        Outout fine tuning method for slow devices
        @param direction accepts FILL_TOPDOWN, FILL_LEFTRIGHT, FILL_DOWNTOP or FILL_RIGHTLEFT
    */
    virtual void setFillDirection(uint8_t direction) {};
    /**
        Fills the screen with the current background color
    */
    void clear();
    /**
        Sets the current background color to the specified color.
        All subsequent relevant graphics operations use this specified color.
        @param r the red component
        @param g the green component
        @param b the blue component
    */
    inline void setBackground(uint8_t r, uint8_t g, uint8_t b) {
        bgBuffer->red = r;
        bgBuffer->green = g;
        bgBuffer->blue = b;
        setBackground(bgBuffer);
    }
    /**
        Sets the current color to the specified color.
        All subsequent graphics operations use this specified color.
        @param r the red component
        @param g the green component
        @param b the blue component
    */
    inline void setColor(uint8_t r, uint8_t g, uint8_t b) {
        fgBuffer->red = r;
        fgBuffer->green = g;
        fgBuffer->blue = b;
        setColor(fgBuffer);
    }
    /**
        Sets the current background color to the specified color.
        All subsequent relevant graphics operations use this specified color.
        @param color color object reference
    */
    inline void setBackground(PRGB* color) {
        background = color;
    }
    /**
        Sets the current color to the specified color.
        All subsequent graphics operations use this specified color.
        @param color color object
    */
    inline void setColor(PRGB* color) {
        foreground = color;
    }
    /**
        Gets the graphics context's current background color.
        @return    the graphics context's current background color.
    */
    inline PRGB* getBackground() {
        return background;
    }
    /**
        Gets the graphics context's current color.
        @return    the graphics context's current color.
    */
    inline PRGB* getColor() {
        return foreground;
    }
    /**
        Gets a pixel color at the point
        <code>(x,&nbsp;y)</code> in the current coordinate system.
        If video RAM read is not supported by the hardware, returns the
        graphics context's current background color
        @param   x  <i>x</i> coordinate.
        @param   y  <i>y</i> coordinate.
        @return  pixel color or the graphics context's current background color.
    */
    PRGB* getPixel(int16_t x, int16_t y);
    /**
        Draws a pixel, using the current color, at the point
        <code>(x,&nbsp;y)</code>
        in the current coordinate system.
        @param   x  <i>x</i> coordinate.
        @param   y  <i>y</i> coordinate.
    */
    void drawPixel(int16_t x, int16_t y);
    /**
        Draws a line, using the current color, between the points
        <code>(x1,&nbsp;y1)</code> and <code>(x2,&nbsp;y2)</code>
        in current coordinate system.
        @param   x1  the first point's <i>x</i> coordinate.
        @param   y1  the first point's <i>y</i> coordinate.
        @param   x2  the second point's <i>x</i> coordinate.
        @param   y2  the second point's <i>y</i> coordinate.
        @see     setOriginRelative()
        @see     setOriginAbsolute()
    */
    void drawLine(int16_t x1, int16_t y1, int16_t x2, int16_t y2);
    /**
        Draws the outline of a circle, defined by center coordinates and a radius,
        with the current color.
        @param       x the <i>x</i> coordinate of the circle center.
        @param       y the <i>y</i> coordinate of the circle center.
        @param       radius circle radius.
        @see         fillCircle(int16_t,int16_t,int16_t)
    */
    void drawCircle(int16_t x, int16_t y, int16_t radius);
    /**
        Draws the outline of an oval.
        The result is a circle or ellipse that fits within the
        rectangle specified by the <code>x</code>, <code>y</code>,
        <code>width</code>, and <code>height</code> arguments.
        <p>
        The oval covers an area that is
        <code>width&nbsp;+&nbsp;1</code> pixels wide
        and <code>height&nbsp;+&nbsp;1</code> pixels tall.
        @param       x the <i>x</i> coordinate of the upper left
                           corner of the oval to be drawn.
        @param       y the <i>y</i> coordinate of the upper left
                           corner of the oval to be drawn.
        @param       width the width of the oval to be drawn.
        @param       height the height of the oval to be drawn.
        @see         fillOval(int16_t,int16_t,int16_t,int16_t)
    */
    void drawOval(int16_t x, int16_t y, int16_t width, int16_t height);
    /**
        Draws the outline of the specified rectangle.
        The left and right edges of the rectangle are at
        <code>x</code> and <code>x&nbsp;+&nbsp;width</code>.
        The top and bottom edges are at
        <code>y</code> and <code>y&nbsp;+&nbsp;height</code>.
        The rectangle is drawn using the current color.
        @param         x   the <i>x</i> coordinate
                               of the rectangle to be drawn.
        @param         y   the <i>y</i> coordinate
                               of the rectangle to be drawn.
        @param         width   the width of the rectangle to be drawn.
        @param         height   the height of the rectangle to be drawn.
        @see           fillRectangle(int16_t,int16_t,int16_t,int16_t)
    */
    void drawRectangle(int16_t x, int16_t y, int16_t width, int16_t height);
    /**
        Draws an outlined round-cornered rectangle using the current color.
        The left and right edges of the rectangle
        are at <code>x</code> and <code>x&nbsp;+&nbsp;width</code>,
        respectively. The top and bottom edges of the rectangle are at
        <code>y</code> and <code>y&nbsp;+&nbsp;height</code>.
        @param      x the <i>x</i> coordinate of the rectangle to be drawn.
        @param      y the <i>y</i> coordinate of the rectangle to be drawn.
        @param      width the width of the rectangle to be drawn.
        @param      height the height of the rectangle to be drawn.
        @param      r horizontal and vertical diameters of the arc
                          at the four corners.
        @see        fillRoundRectangle(int16_t,int16_t,int16_t,int16_t,int16_t)
    */
    void drawRoundRectangle(int16_t x, int16_t y, int16_t width, int16_t height, int16_t r);
    /**
        Fills a circle, defined by center coordinates and a radius, with the current color.
        @param       x the <i>x</i> coordinate of the circle center.
        @param       y the <i>y</i> coordinate of the circle center.
        @param       radius circle radius.
        @see         drawCircle(int16_t,int16_t,int16_t)
    */
    void fillCircle(int16_t x, int16_t y, int16_t radius);
    /**
        Fills an oval bounded by the specified rectangle with the
        current color.
        @param       x the <i>x</i> coordinate of the upper left corner
                           of the oval to be filled.
        @param       y the <i>y</i> coordinate of the upper left corner
                           of the oval to be filled.
        @param       width the width of the oval to be filled.
        @param       height the height of the oval to be filled.
        @see         drawOval(int16_t,int16_t,int16_t,int16_t)
    */
    void fillOval(int16_t x, int16_t y, int16_t width, int16_t height);
    /**
        Fills the specified rectangle.
        The left and right edges of the rectangle are at
        <code>x</code> and <code>x&nbsp;+&nbsp;width&nbsp;-&nbsp;1</code>.
        The top and bottom edges are at
        <code>y</code> and <code>y&nbsp;+&nbsp;height&nbsp;-&nbsp;1</code>.
        The resulting rectangle covers an area
        <code>width</code> pixels wide by
        <code>height</code> pixels tall.
        The rectangle is filled using the current color.
        @param         x   the <i>x</i> coordinate
                               of the rectangle to be filled.
        @param         y   the <i>y</i> coordinate
                               of the rectangle to be filled.
        @param         width   the width of the rectangle to be filled.
        @param         height   the height of the rectangle to be filled.
        @see           drawRectangle(int16_t,int16_t,int16_t,int16_t)
    */
    void fillRectangle(int16_t x, int16_t y, int16_t width, int16_t height);
    /**
        Fills the specified rounded corner rectangle with the current color.
        The left and right edges of the rectangle
        are at <code>x</code> and <code>x&nbsp;+&nbsp;width&nbsp;-&nbsp;1</code>,
        respectively. The top and bottom edges of the rectangle are at
        <code>y</code> and <code>y&nbsp;+&nbsp;height&nbsp;-&nbsp;1</code>.
        @param       x the <i>x</i> coordinate of the rectangle to be filled.
        @param       y the <i>y</i> coordinate of the rectangle to be filled.
        @param       width the width of the rectangle to be filled.
        @param       height the height of the rectangle to be filled.
        @param       r horizontal and vertical diameters of the arc at the four corners.
        @see         drawRoundRectangle(int16_t,int16_t,int16_t,int16_t,int16_t)
    */
    void fillRoundRectangle(int16_t x, int16_t y, int16_t width, int16_t height, int16_t r);
    /**
        Draws specified bitmap image.
        The image is drawn with its top-left corner at
        (<i>x</i>,&nbsp;<i>y</i>) in the current coordinate
        space.
        @param    data the specified bitmap image to be drawn. This method does
                     nothing if <code>img</code> is null.
        @param    x   the <i>x</i> coordinate.
        @param    y   the <i>y</i> coordinate.
        @param    width   the width of the image.
        @param    height   the height of the image.
        @see      loadBitmap(int16_t,int16_t,int16_t,int16_t,String)
    */
    int8_t drawBitmap(int16_t x, int16_t y, int16_t width, int16_t height, prog_uint16_t* data);
    /**
        Draws specified bitmap image.
        The image is drawn with its top-left corner at
        (<i>x</i>,&nbsp;<i>y</i>) in the current coordinate
        space.
        @param    data compressed (with Pixelmeister) bitmap image bytes. This method does
                     nothing if <code>img</code> is null.
        @param    x   the <i>x</i> coordinate.
        @param    y   the <i>y</i> coordinate.
        @see      drawBitmap(int16_t,int16_t,int16_t,int16_t,int[])
    */
    int8_t drawCompressedBitmap(int16_t x, int16_t y, uint8_t* data);
    /**
        Draws an icon, prepared with Pixelmeister.
        The icon is drawn with its top-left corner at
        (<i>x</i>,&nbsp;<i>y</i>) in the current coordinate
        space.
        @param    data icon image bytes. This method does
                     nothing if <code>data</code> is null.
        @param    x   the <i>x</i> coordinate.
        @param    y   the <i>y</i> coordinate.
    */
    void drawIcon(int16_t xx, int16_t yy, prog_uchar data[]);
    /**
        Paint icon pixels with background color. The icon should be in Pixelmeister format.
        The icon is drawn with its top-left corner at
        (<i>x</i>,&nbsp;<i>y</i>) in the current coordinate
        space.
        @param    data icon image bytes. This method does
                     nothing if <code>data</code> is null.
        @param    x   the <i>x</i> coordinate.
        @param    y   the <i>y</i> coordinate.
    */
    void cleanIcon(int16_t xx, int16_t yy, prog_uchar data[]);
    /**
        @return height of an icon, created with Pixelmeister
        @param    data icon image bytes.
    */
    int16_t getIconHeight(prog_uchar* data) {
        return pgm_read_byte_near(data + 4);
    }
    /**
        @return width of an icon, created with Pixelmeister
        @param    data icon image bytes.
    */
    int16_t getIconWidth(prog_uchar* data) {
        return pgm_read_byte_near(data + 5);
    }
    /**
        Loads from an external FAT-drive and draws specified bitmap image.
        The image is drawn with its top-left corner at
        (<i>x</i>,&nbsp;<i>y</i>) in the current coordinate
        space.
        @param    path to the image.
        @param    x   the <i>x</i> coordinate.
        @param    y   the <i>y</i> coordinate.
        @param    width   the width of the image.
        @param    height   the height of the image.
        @see      drawBitmap(int16_t,int16_t,int16_t,int16_t,int[])
    */
    int8_t loadBitmap(int16_t x, int16_t y, int16_t width, int16_t height, String path);
    /**
        Under construction
    */
    void scroll(int16_t dy, int16_t x1, int16_t x2, int8_t flags);
    /**
        Scrolls the display content to a given number of pixels (if the device controller
        supports scrolling). Scroll axis is vertical by portrait orientation and horizontal
        by landscape orientation (hardware scpecifics).
        SCROLL_CLEAN flag forces to paint wrapped regions with background color. SCROLL_SMOOTH
        eases begin and end of a scroll movement (by big dy values).
        @param dy negative or positive scroll distance
        @param flags can be 0, SCROLL_SMOOTH or/and SCROLL_CLEAN
    */
    void scroll(int16_t dy, int8_t flags);
    /**
        Sets this graphics context's font to the specified font.
        All subsequent text operations using the context use this font.
        @param  font   a font, converted from TTF with
        <a href="http://pd4ml.com/pixelmeister/">Pixelmeister</a>.
    */
    int setFont(prog_uchar font[]);
    /**
        Draws the text given by the specified string, using current font and color.
        The baseline of the leftmost character is at position (<i>x</i>,&nbsp;<i>y</i>)
        in the current coordinate system.
        @param       text      the string to be drawn.
        @param       xx        the <i>x</i> coordinate.
        @param       yy        the <i>y</i> coordinate.
        @param       kerning   optional array of integer kerning values in a range from
        -99 to 99 to be applied to the string glyphs correspondingly. "-100" value ends
        the kerning data. If the string has more characters than the array length, a value
        precedes "-100" is used for the rest of the string glyphs.
        @see         setFont(prog_uchar font[])
        @see         setOriginRelative()
        @see         setOriginAbsolute()
        @see         cleanText(int16_t,int16_t,String,int8_t[])
    */
    void print(int16_t xx, int16_t yy, String text, int8_t kerning[] = NULL);
    /**
        The method oposes print(int16_t,int16_t,String,int8_t[]) Erases the text given by
        the specified string by filling glyph shapes with the current background color.
        The baseline of the leftmost character is at position (<i>x</i>,&nbsp;<i>y</i>)
        in the current coordinate system.
        @param       text      the string to be erased.
        @param       xx        the <i>x</i> coordinate.
        @param       yy        the <i>y</i> coordinate.
        @param       kerning   aptional array of integer kerning values in a range from
        -99 to 99 to be applied to the string glyphs correspondingly. "-100" value ends
        the kerning data. If the string has more characters than the array length, a value
        precedes "-100" is usedas a kerning hint for the rest of the string glyphs.
        @see         setFont(prog_uchar font[])
        @see         setOriginRelative()
        @see         setOriginAbsolute()
        @see         print(int16_t,int16_t,String,int8_t[])
    */
    void cleanText(int16_t xx, int16_t yy, String text, int8_t kerning[] = NULL);
    /**
        Gets the current font text line height
        @return text line height in pixels
    */
    int16_t getTextLineHeight();
    /**
        Gets the current font baseline offsett
        @return text baseline offset
    */
    int16_t getTextBaseline();
    /**
        Computes needed horizontal space to print the given text with print(int16_t,int16_t,String,int8_t)
        @param       text      the text string.
        @param       kerning   optional array of integer kerning values in a range from
        -99 to 99 to be applied to the string glyphs correspondingly. "-100" value ends
        the kerning data. If the string has more characters than the array length, a value
        precedes "-100" is used as a kerning hint for the rest of the string glyphs.
        @see         print(int16_t,int16_t,String,int8_t[])
        @return text baseline offset
    */
    int16_t getTextWidth(String text, int8_t kerning[] = NULL);
};

class BitStream
{
  private:
    uint8_t* data;
    size_t size;
    int32_t bitpos;

  public:
    BitStream(uint8_t* src_buffer, size_t byte_size, int8_t offset = 0) {
        bitpos = offset;
        data = src_buffer;
        size = byte_size + (offset >> 3);
    }

    bool endOfData() {
        return (unsigned)((bitpos + 1) >> 3) >= size;
    }

    uint8_t testCurrentByte() {
        uint8_t res = (uint8_t)pgm_read_byte_near(data + (bitpos >> 3));
        return res;
    }

    uint8_t readBit() {
        uint8_t res = (uint8_t)(pgm_read_byte_near(data + (bitpos >> 3)) & (uint8_t)((uint16_t)0x80 >> (bitpos & 7)));
        bitpos++;
        return res;
    }

    uint8_t readBits(uint8_t len) {

        uint16_t end_offset = (bitpos + len - 1) >> 3;
        if (end_offset >= size) {
            return 0;
        }

        uint8_t i;
        uint16_t byte_offset = bitpos >> 3;
        if (byte_offset == end_offset) {
            uint16_t x = pgm_read_byte_near(data + byte_offset);
            i = (uint8_t)(x >> (8 - ((bitpos & 7) + len))) & ((1 << len) - 1);
        }
        else {
            uint16_t x = ((uint16_t)pgm_read_byte_near(data + byte_offset) << 8) + pgm_read_byte_near(data + end_offset);
            i = (uint8_t)(x >> (16 - ((bitpos & 7) + len))) & ((1 << len) - 1);
        }
        bitpos += len;
        return i;
    }

    uint16_t readNumber() {
        int16_t count;

        int8_t ctr = 1;
        int16_t base = 2;
        do {
            if (readBit() == 0) {
                uint8_t bits = readBits(ctr);
                count = base + bits;
                break;
            }
            else {
                ctr++;
                base *= 2;
                if (ctr == 7) {
                    uint8_t bits = readBits(ctr);
                    count = base + bits;
                    break;
                }
            }
        }
        while (true);

        return (uint16_t)count;
    }
};

#endif