LCD4bpp

This class contains the various low-level drawing routines for drawing bitmaps, texts and rectangles on 4 bits per pixel grayscale displays.

See: LCD

Note: All coordinates are expected to be in absolute coordinates!

Inherits from: LCD

Public Functions

virtual uint8_t	bitDepth() const
	Number of bits per pixel used by the display.
virtual void	blitCopy(const uint16_t * sourceData, const Rect & source, const Rect & blitRect, uint8_t alpha, bool hasTransparentPixels)
	Blits (directly copies) a block of data to the framebuffer, performing alpha blending (and tranparency keying) as specified.
virtual void	blitCopy(const uint8_t * sourceData, Bitmap::BitmapFormat sourceFormat, const Rect & source, const Rect & blitRect, uint8_t alpha, bool hasTransparentPixels)
	Blits (directly copies) a block of data to the framebuffer, performing alpha blending (and tranparency keying) as specified.
virtual uint16_t *	copyFrameBufferRegionToMemory(const Rect & visRegion, const Rect & absRegion, const BitmapId bitmapId)
	Copies part of the framebuffer to the data section of a bitmap.
virtual void	drawPartialBitmap(const Bitmap & bitmap, int16_t x, int16_t y, const Rect & rect, uint8_t alpha =255, bool useOptimized =true)
	Draws all (or a part) of a bitmap.
void	enableTextureMapperA4()
	Enables the texture mappers for A4 image format.
void	enableTextureMapperA4_BilinearInterpolation()
	Enables the texture mappers for A4 image format.
void	enableTextureMapperA4_NearestNeighbor()
	Enables the texture mappers for A4 image format.
void	enableTextureMapperAll()
	Enables the texture mappers for all image formats.
void	enableTextureMapperGRAY4()
	Enables the texture mappers for GRAY4 image format.
void	enableTextureMapperGRAY4_BilinearInterpolation()
	Enables the texture mappers for GRAY4 image format.
void	enableTextureMapperGRAY4_NearestNeighbor()
	Enables the texture mappers for GRAY4 image format.
virtual void	fillBuffer(uint8_t *const destination, uint16_t pixelStride, const Rect & rect, const colortype color, const uint8_t alpha)
	Draws a filled rectangle in destination memory using the specified color and opacity.
virtual void	fillRect(const Rect & rect, colortype color, uint8_t alpha =255)
	Draws a filled rectangle in the framebuffer in the specified color and opacity.
virtual Bitmap::BitmapFormat	framebufferFormat() const
	Framebuffer format used by the display.
virtual uint16_t	framebufferStride() const
	Framebuffer stride in bytes.
	LCD4bpp()
virtual void	setDefaultColor(colortype color)
	Sets default color as used by alpha level only bitmap formats, e.g.
FORCE_INLINE_FUNCTION uint16_t	getFramebufferStride()
	Framebuffer stride in bytes.
FORCE_INLINE_FUNCTION uint8_t	getNativeColor(colortype color)
	Generates a color representation to be used on the LCD, based on 24 bit RGB values.
FORCE_INLINE_FUNCTION uint8_t	getNativeColorFromRGB(uint8_t red, uint8_t green, uint8_t blue)
	Generates a color representation to be used on the LCD, based on 24 bit RGB values.
FORCE_INLINE_FUNCTION uint8_t	getPixel(const uint16_t * addr, int offset)
	Get pixel from buffer/image.
FORCE_INLINE_FUNCTION uint8_t	getPixel(const uint8_t * addr, int offset)
	Get pixel from buffer/image.
FORCE_INLINE_FUNCTION void	setPixel(uint16_t * addr, int offset, uint8_t value)
	Set pixel in buffer.
FORCE_INLINE_FUNCTION void	setPixel(uint8_t * addr, int offset, uint8_t value)
	Set pixel in buffer.

Protected Functions

void	copyRect(const uint8_t srcAddress, uint16_t srcStride, uint8_t srcPixelOffset, uint8_t RESTRICT dstAddress, uint16_t dstStride, uint8_t dstPixelOffset, uint16_t width, uint16_t height) const
	Copies a rectangular area.
virtual void	drawGlyph(uint16_t wbuf16, Rect widgetArea, int16_t x, int16_t y, uint16_t offsetX, uint16_t offsetY, const Rect & invalidatedArea, const GlyphNode glyph, const uint8_t * glyphData, uint8_t byteAlignRow, colortype color, uint8_t bitsPerPixel, uint8_t alpha, TextRotation rotation)
	Private version of draw-glyph with explicit destination buffer pointer argument.
virtual DrawTextureMapScanLineBase *	getTextureMapperDrawScanLine(const TextureSurface & texture, RenderingVariant renderVariant, uint8_t alpha)
	Gets pointer to object that can draw a scan line which allows for highly specialized and optimized implementation.
void	blitCopyAlphaPerPixel(const uint16_t sourceData16, const uint8_t sourceAlphaData, const Rect & source, const Rect & blitRect, uint8_t alpha)
	Blit a 2D source-array to the framebuffer performing alpha-blending per pixel as specified Performs always a software blend.
int	nextLine(bool rotatedDisplay, TextRotation textRotation)
	Find out how much to advance in the display buffer to get to the next line.
int	nextPixel(bool rotatedDisplay, TextRotation textRotation)
	Find out how much to advance in the display buffer to get to the next pixel.

Protected Attributes

uint8_t	defaultColor4
	Default Color to use when displaying transparency-only elements, e.g. A4 bitmaps.

Additional inherited members

Public Classes inherited from LCD

struct	StringVisuals
	The visual elements when writing a string.

Protected Classes inherited from LCD

class	DrawTextureMapScanLineBase
	Base class for drawing scanline by the texture mapper.

Public Functions inherited from LCD

void	drawString(Rect widgetArea, const Rect & invalidatedArea, const StringVisuals & stringVisuals, const Unicode::UnicodeChar * format, ... )
	Draws the specified Unicode string.
virtual void	drawTextureMapQuad(const DrawingSurface & dest, const Point3D * vertices, const TextureSurface & texture, const Rect & absoluteRect, const Rect & dirtyAreaAbsolute, RenderingVariant renderVariant, uint8_t alpha =255, uint16_t subDivisionSize =12)
	Texture map quad.
virtual void	drawTextureMapTriangle(const DrawingSurface & dest, const Point3D * vertices, const TextureSurface & texture, const Rect & absoluteRect, const Rect & dirtyAreaAbsolute, RenderingVariant renderVariant, uint8_t alpha =255, uint16_t subDivisionSize =12)
	Texture map triangle.
colortype	getDefaultColor() const
	Gets default color previously set using setDefaultColor.
	LCD()
	Initializes a new instance of the LCD class.
virtual	~LCD()
	Finalizes an instance of the LCD class.
FORCE_INLINE_FUNCTION uint8_t	div255(uint16_t num)
	Approximates an integer division of a 16bit value by 255.
FORCE_INLINE_FUNCTION uint32_t	div255g(uint32_t pixelxAlpha)
	Divides the green component of pixelxAlpha by 255.
FORCE_INLINE_FUNCTION uint32_t	div255rb(uint32_t pixelxAlpha)
	Divides the red and blue components of pixelxAlpha by 255.

Protected Functions inherited from LCD

void	drawStringLTR(const Rect & widgetArea, const Rect & invalidatedArea, const StringVisuals & visuals, const Unicode::UnicodeChar * format, va_list pArg)
	Draws the specified Unicode string.
void	drawStringRTL(const Rect & widgetArea, const Rect & invalidatedArea, const StringVisuals & visuals, const Unicode::UnicodeChar * format, va_list pArg)
	Draws the specified Unicode string.
virtual void	drawTextureMapScanLine(const DrawingSurface & dest, const Gradients & gradients, const Edge leftEdge, const Edge rightEdge, const TextureSurface & texture, const Rect & absoluteRect, const Rect & dirtyAreaAbsolute, RenderingVariant renderVariant, uint8_t alpha, uint16_t subDivisionSize)
	Draw scan line.
FORCE_INLINE_FUNCTION uint8_t	getAlphaFromA4(const uint16_t * data, uint32_t offset)
	Gets alpha from A4 image at given offset.
uint16_t	getNumLines(TextProvider & textProvider, WideTextAction wideTextAction, TextDirection textDirection, const Font * font, int16_t width)
	Gets number of lines for a given text taking word wrap into consideration.
int	realX(const Rect & widgetArea, int16_t x, int16_t y, TextRotation rotation)
	Find the real, absolute x coordinate of a point inside a widget with regards to rotation.
int	realY(const Rect & widgetArea, int16_t x, int16_t y, TextRotation rotation)
	Find the real, absolute y coordinate of a point inside a widget with regards to rotation.
void	rotateRect(Rect & rect, const Rect & canvas, const TextRotation rotation)
	Rotate a rectangle inside another rectangle.
uint16_t	stringWidth(TextProvider & textProvider, const Font & font, const int numChars, TextDirection textDirection)
	Find string width of the given number of ligatures read from the given TextProvider.

Protected Attributes inherited from LCD

colortype	defaultColor
	Default Color to use when displaying transparency-only elements, e.g. A4 bitmaps.
const uint16_t	newLine
	NewLine value.

Public Functions Documentation

bitDepth

virtual uint8_t bitDepth	(			)	const

Number of bits per pixel used by the display.

Returns:

The number of bits per pixel.

Reimplements: touchgfx::LCD::bitDepth

blitCopy

virtual void blitCopy	(	const uint16_t *	sourceData ,
		const Rect &	source ,
		const Rect &	blitRect ,
		uint8_t	alpha ,
		bool	hasTransparentPixels
		)

Blits (directly copies) a block of data to the framebuffer, performing alpha blending (and tranparency keying) as specified.

Performs a software blend if HAL does not support BLIT_COPY_WITH_ALPHA and alpha != 255 (solid).

Parameters:

sourceData	The source array pointer (points to the beginning of the data). The sourceData must be stored in a format suitable for the selected display.
source	The position and dimensions of the source. The x and y of this rect should both be 0.
blitRect	A rectangle describing what region of the sourceData is to be copied to the framebuffer.
alpha	The alpha value to use for blending ranging from 0=invisible to 255=solid=no blending.
hasTransparentPixels	If true, this data copy contains transparent pixels and require hardware support for that to be enabled.

Reimplements: touchgfx::LCD::blitCopy

blitCopy

virtual void blitCopy	(	const uint8_t *	sourceData ,
		Bitmap::BitmapFormat	sourceFormat ,
		const Rect &	source ,
		const Rect &	blitRect ,
		uint8_t	alpha ,
		bool	hasTransparentPixels
		)

Blits (directly copies) a block of data to the framebuffer, performing alpha blending (and tranparency keying) as specified.

Performs a software blend if HAL does not support BLIT_COPY_WITH_ALPHA and alpha < 255 (solid).

If the display does not support the specified sourceFormat, an assert will be raised.

Parameters:

sourceData	The source array pointer (points to the beginning of the data). The sourceData must be stored in a format suitable for the selected display.
sourceFormat	The bitmap format used in the source data.
source	The position and dimensions of the source. The x and y of this rect should both be 0.
blitRect	A rectangle describing what region of the sourceData is to be copied to the framebuffer.
alpha	The alpha value to use for blending ranging from 0=invisible to 255=solid=no blending.
hasTransparentPixels	If true, this data copy contains transparent pixels and require hardware support for that to be enabled.

Reimplements: touchgfx::LCD::blitCopy

copyFrameBufferRegionToMemory

virtual uint16_t * copyFrameBufferRegionToMemory	(	const Rect &	visRegion ,
		const Rect &	absRegion ,
		const BitmapId	bitmapId
		)

Copies part of the framebuffer to the data section of a bitmap.

The bitmap must be a dynamic bitmap or animation storage (BITMAP_ANIMATION_STORAGE). The two regions given are the visible region and the absolute region on screen. This is used to copy only a part of the framebuffer. This might be the case if a SnapshotWidget is placed inside a Container where parts of the SnapshowWidget is outside the area defined by the Container. The visible region must be completely inside the absolute region.

Parameters:

visRegion	The visible region.
absRegion	The absolute region.
bitmapId	Identifier for the bitmap.

Returns:

Null if it fails, else a pointer to the data in the given bitmap.

Note

There is only one instance of animation storage. The content of the bitmap data /animation storage outside the given region is left untouched.

See also:

blitCopy

Reimplements: touchgfx::LCD::copyFrameBufferRegionToMemory

drawPartialBitmap

virtual void drawPartialBitmap	(	const Bitmap &	bitmap ,
		int16_t	x ,
		int16_t	y ,
		const Rect &	rect ,
		uint8_t	alpha =255,
		bool	useOptimized =true
		)

Draws all (or a part) of a bitmap.

The coordinates of the corner of the bitmap is given in (x, y) and rect describes which part of the bitmap should be drawn. The bitmap can be drawn as it is or more or less transparent depending on the value of alpha. The value of alpha is independent of the transparency of the individual pixels of the given bitmap.

Parameters:

bitmap	The bitmap to draw.
x	The absolute x coordinate to place (0, 0) of the bitmap on the screen.
y	The absolute y coordinate to place (0, 0) of the bitmap on the screen.
rect	A rectangle describing what region of the bitmap is to be drawn.
alpha	(Optional) Optional alpha value ranging from 0=invisible to 255=solid. Default is 255 (solid).
useOptimized	(Optional) if false, do not attempt to substitute (parts of) this bitmap with faster fillrects.

Reimplements: touchgfx::LCD::drawPartialBitmap

enableTextureMapperA4

void enableTextureMapperA4	(			)

Enables the texture mappers for A4 image format.

This allows drawing A4 images using Bilinear Interpolation and Nearest Neighbor algorithms.

See also:

enableTextureMapperA4_BilinearInterpolation, enableTextureMapperA4_NearestNeighbor

enableTextureMapperA4_BilinearInterpolation

void enableTextureMapperA4_BilinearInterpolation	(			)

Enables the texture mappers for A4 image format.

This allows drawing A4 images using Bilinear Interpolation algorithm.

See also:

enableTextureMapperA4, enableTextureMapperA4_NearestNeighbor

enableTextureMapperA4_NearestNeighbor

void enableTextureMapperA4_NearestNeighbor	(			)

Enables the texture mappers for A4 image format.

This allows drawing A4 images using Nearest Neighbor algorithm.

See also:

enableTextureMapperA4, enableTextureMapperA4_BilinearInterpolation

enableTextureMapperAll

void enableTextureMapperAll	(			)

Enables the texture mappers for all image formats.

This allows drawing any image using Bilinear Interpolation and Nearest Neighbor algorithms, but might use a lot of memory for the drawing algorithms.

enableTextureMapperGRAY4

void enableTextureMapperGRAY4	(			)

Enables the texture mappers for GRAY4 image format.

This allows drawing GRAY4 images using Bilinear Interpolation and Nearest Neighbor algorithms.

See also:

enableTextureMapperGRAY4_BilinearInterpolation, enableTextureMapperGRAY4_NearestNeighbor

enableTextureMapperGRAY4_BilinearInterpolation

void enableTextureMapperGRAY4_BilinearInterpolation	(			)

Enables the texture mappers for GRAY4 image format.

This allows drawing GRAY4 images using Bilinear Interpolation algorithm.

See also:

enableTextureMapperGRAY4, enableTextureMapperGRAY4_NearestNeighbor

enableTextureMapperGRAY4_NearestNeighbor

void enableTextureMapperGRAY4_NearestNeighbor	(			)

Enables the texture mappers for GRAY4 image format.

This allows drawing GRAY4 images using Nearest Neighbor algorithm.

See also:

enableTextureMapperGRAY4, enableTextureMapperGRAY4_BilinearInterpolation

fillBuffer

virtual void fillBuffer	(	uint8_t *const	destination ,
		uint16_t	pixelStride ,
		const Rect &	rect ,
		const colortype	color ,
		const uint8_t	alpha
		)

Draws a filled rectangle in destination memory using the specified color and opacity.

The destination memory must have the same format as the display framebuffer. By default the rectangle will be drawn as a solid box. The rectangle can be drawn with transparency by specifying alpha from 0=invisible to 255=solid.

Parameters:

destination	The start of the memory area to fill.
pixelStride	The pixel stride, i.e. number of pixels in a row.
rect	The rectangle to fill absolute coordinates.
color	The rectangle color.
alpha	The rectangle opacity, from 0=invisible to 255=solid.

Note

The pixelStride is rounded up to nearest whole bytes for displays with more than one pixel per byte (LCD1bpp, LCD2bpp and LCD4bpp)

Reimplements: touchgfx::LCD::fillBuffer

fillRect

virtual void fillRect	(	const Rect &	rect ,
		colortype	color ,
		uint8_t	alpha =255
		)

Draws a filled rectangle in the framebuffer in the specified color and opacity.

By default the rectangle will be drawn as a solid box. The rectangle can be drawn with transparency by specifying alpha from 0=invisible to 255=solid.

Parameters:

rect	The rectangle to draw in absolute display coordinates.
color	The rectangle color.
alpha	(Optional) The rectangle opacity, from 0=invisible to 255=solid.

See also:

fillBuffer

Reimplements: touchgfx::LCD::fillRect

framebufferFormat

virtual Bitmap::BitmapFormat framebufferFormat	(			)	const

Framebuffer format used by the display.

Returns:

A Bitmap::BitmapFormat.

Reimplements: touchgfx::LCD::framebufferFormat

framebufferStride

virtual uint16_t framebufferStride	(			)	const

Framebuffer stride in bytes.

The distance (in bytes) from the start of one framebuffer row, to the next.

Returns:

The number of bytes in one framebuffer row.

Reimplements: touchgfx::LCD::framebufferStride

LCD4bpp

LCD4bpp	(			)

setDefaultColor

virtual void setDefaultColor	(	colortype	color	)

Sets default color as used by alpha level only bitmap formats, e.g.

A4. The default color, if no color is set, is black.

Parameters:

color	The color.

See also:

getDefaultColor

Reimplements: touchgfx::LCD::setDefaultColor

getFramebufferStride

static FORCE_INLINE_FUNCTION uint16_t getFramebufferStride	(			)

Framebuffer stride in bytes.

The distance (in bytes) from the start of one framebuffer row, to the next.

Returns:

The number of bytes in one framebuffer row.

getNativeColor

static FORCE_INLINE_FUNCTION uint8_t getNativeColor	(	colortype	color	)

Generates a color representation to be used on the LCD, based on 24 bit RGB values.

Parameters:

color	The color.

Returns:

The color representation depending on LCD color format.

getNativeColorFromRGB

static FORCE_INLINE_FUNCTION uint8_t getNativeColorFromRGB	(	uint8_t	red ,
		uint8_t	green ,
		uint8_t	blue
		)

Generates a color representation to be used on the LCD, based on 24 bit RGB values.

Parameters:

red	Value of the red part (0-255).
green	Value of the green part (0-255).
blue	Value of the blue part (0-255).

Returns:

The color representation depending on LCD color format.

getPixel

static FORCE_INLINE_FUNCTION uint8_t getPixel	(	const uint16_t *	addr ,
		int	offset
		)

Get pixel from buffer/image.

Parameters:

addr	The address.
offset	The offset.

Returns:

The pixel value.

getPixel

static FORCE_INLINE_FUNCTION uint8_t getPixel	(	const uint8_t *	addr ,
		int	offset
		)

Get pixel from buffer/image.

Parameters:

addr	The address.
offset	The offset.

Returns:

The pixel value.

setPixel

static FORCE_INLINE_FUNCTION void setPixel	(	uint16_t *	addr ,
		int	offset ,
		uint8_t	value
		)

Set pixel in buffer.

Parameters:

addr	The address.
offset	The offset.
value	The value.

setPixel

static FORCE_INLINE_FUNCTION void setPixel	(	uint8_t *	addr ,
		int	offset ,
		uint8_t	value
		)

Set pixel in buffer.

Parameters:

addr	The address.
offset	The offset.
value	The value.

Protected Functions Documentation

copyRect

void copyRect	(	const uint8_t *	srcAddress ,		const
		uint16_t	srcStride ,		const
		uint8_t	srcPixelOffset ,		const
		uint8_t *RESTRICT	dstAddress ,		const
		uint16_t	dstStride ,		const
		uint8_t	dstPixelOffset ,		const
		uint16_t	width ,		const
		uint16_t	height		const
		)	const

Copies a rectangular area.

Parameters:

srcAddress	Source address (byte address).
srcStride	Source stride (number of bytes to advance to next line).
srcPixelOffset	Source pixel offset (first pixel in first source byte).
dstAddress	If destination address (byte address).
dstStride	Destination stride (number of bytes to advance to next line).
dstPixelOffset	Destination pixel offset (first pixel in destination byte).
width	The width of area (in pixels).
height	The height of area (in pixels).

drawGlyph

virtual void drawGlyph	(	uint16_t *	wbuf16 ,
		Rect	widgetArea ,
		int16_t	x ,
		int16_t	y ,
		uint16_t	offsetX ,
		uint16_t	offsetY ,
		const Rect &	invalidatedArea ,
		const GlyphNode *	glyph ,
		const uint8_t *	glyphData ,
		uint8_t	byteAlignRow ,
		colortype	color ,
		uint8_t	bitsPerPixel ,
		uint8_t	alpha ,
		TextRotation	rotation
		)

Private version of draw-glyph with explicit destination buffer pointer argument.

For all parameters (except the buffer pointer) see the public function drawString().

Parameters:

wbuf16	The destination (frame) buffer to draw to.
widgetArea	The canvas to draw the glyph inside.
x	Horizontal offset to start drawing the glyph.
y	Vertical offset to start drawing the glyph.
offsetX	Horizontal offset in the glyph to start drawing from.
offsetY	Vertical offset in the glyph to start drawing from.
invalidatedArea	The area to draw inside.
glyph	Specifications of the glyph to draw.
glyphData	Data containing the actual glyph (dense format)
byteAlignRow	Each row of glyph data starts in a new byte.
color	The color of the glyph.
bitsPerPixel	Bit depth of the glyph.
alpha	The transparency of the glyph.
rotation	Rotation to do before drawing the glyph.

Reimplements: touchgfx::LCD::drawGlyph

getTextureMapperDrawScanLine

virtual DrawTextureMapScanLineBase * getTextureMapperDrawScanLine	(	const TextureSurface &	texture ,
		RenderingVariant	renderVariant ,
		uint8_t	alpha
		)

Gets pointer to object that can draw a scan line which allows for highly specialized and optimized implementation.

Parameters:

texture	The texture Surface.
renderVariant	The render variant.
alpha	The global alpha.

Returns:

Null if it fails, else the pointer to the texture mapper draw scan line object.

Reimplements: touchgfx::LCD::getTextureMapperDrawScanLine

blitCopyAlphaPerPixel

static void blitCopyAlphaPerPixel	(	const uint16_t *	sourceData16 ,
		const uint8_t *	sourceAlphaData ,
		const Rect &	source ,
		const Rect &	blitRect ,
		uint8_t	alpha
		)

Blit a 2D source-array to the framebuffer performing alpha-blending per pixel as specified Performs always a software blend.

Parameters:

sourceData16	The source-array pointer (points to the beginning of the data). The sourceData must be stored as 4bpp GRAY4 values.
sourceAlphaData	The alpha channel array pointer (points to the beginning of the data)
source	The location and dimensions of the source.
blitRect	A rectangle describing what region is to be drawn.
alpha	The alpha value to use for blending applied to the whole image (255 = solid, no blending)

nextLine

static int nextLine	(	bool	rotatedDisplay ,
		TextRotation	textRotation
		)

Find out how much to advance in the display buffer to get to the next line.

Parameters:

rotatedDisplay	Is the display running in portrait mode?
textRotation	Rotation to perform.

Returns:

How much to advance to get to the next line.

nextPixel

static int nextPixel	(	bool	rotatedDisplay ,
		TextRotation	textRotation
		)

Find out how much to advance in the display buffer to get to the next pixel.

Parameters:

rotatedDisplay	Is the display running in portrait mode?
textRotation	Rotation to perform.

Returns:

How much to advance to get to the next pixel.

Protected Attributes Documentation

defaultColor4

uint8_t defaultColor4

Default Color to use when displaying transparency-only elements, e.g. A4 bitmaps.