PainterGRAY4Bitmap

PainterGRAY4Bitmap will take the color for a given point in the shape from a bitmap. Please be aware, the the bitmap is used by the CanvasWidgetRendere (not Shape), so any rotation you might specify for a CanvasWidget (e.g. Shape) is not applied to the bitmap as CWR is not aware of this rotation.

See: AbstractPainter

Inherits from: AbstractPainterGRAY4, AbstractPainter

Public Functions

	PainterGRAY4Bitmap(const Bitmap & bmp =Bitmap(BITMAP_INVALID))
	Initializes a new instance of the PainterGRAY4Bitmap class.
virtual void	render(uint8_t ptr, int x, int xAdjust, int y, unsigned count, const uint8_t covers)
	Paint a designated part of the RenderingBuffer with respect to the amount of coverage of each pixel given by the parameter covers.
void	setBitmap(const Bitmap & bmp)
	Sets a bitmap to be used when drawing the CanvasWidget.

Protected Functions

virtual bool	renderInit()
	Initialize rendering of a single scan line of pixels for the render.
virtual bool	renderNext(uint8_t & gray, uint8_t & alpha)
	Get the color of the next pixel in the scan line to blend into the framebuffer.

Protected Attributes

Bitmap	bitmap
	The bitmap to be used when painting.
const uint8_t *	bitmapAlphaPointer
	Pointer to the bitmap alpha data for GRAY4.
const uint8_t *	bitmapGRAY4Pointer
	Pointer to the bitmap (GRAY4)
Rect	bitmapRectToFrameBuffer
	Bitmap rectangle translated to framebuffer coordinates.

Additional inherited members

Public Functions inherited from AbstractPainterGRAY4

	AbstractPainterGRAY4()

Protected Functions inherited from AbstractPainterGRAY4

virtual void	renderPixel(uint8_t * p, uint16_t offset, uint8_t gray)
	Renders (writes) the specified color into the framebuffer.

Protected Attributes inherited from AbstractPainterGRAY4

int	currentX
	Current x coordinate relative to the widget.
int	currentY
	Current y coordinate relative to the widget.

Public Functions inherited from AbstractPainter

	AbstractPainter()
	Initializes a new instance of the AbstractPainter class.
void	setOffset(uint16_t offsetX, uint16_t offsetY)
	Sets the offset of the area being drawn.
virtual	~AbstractPainter()
	Finalizes an instance of the AbstractPainter class.

Protected Functions inherited from AbstractPainter

void	setWidgetAlpha(const uint8_t alpha)
	Sets the widget alpha to allow an entire canvas widget to easily be faded without changing the painter of the widget.
FORCE_INLINE_FUNCTION bool	compatibleFramebuffer(Bitmap::BitmapFormat format)
	Helper function to check if the provided bitmap format matches the current framebuffer format.

Protected Attributes inherited from AbstractPainter

int16_t	areaOffsetX
	The offset x coordinate of the area being drawn.
int16_t	areaOffsetY
	The offset y coordinate of the area being drawn.
uint8_t	widgetAlpha
	The alpha of the widget using the painter.

Public Functions Documentation

PainterGRAY4Bitmap

PainterGRAY4Bitmap	(	const Bitmap &	bmp =Bitmap(BITMAP_INVALID)	)

Initializes a new instance of the PainterGRAY4Bitmap class.

Parameters:

bmp	(Optional) The bitmap, default is BITMAP_INVALID.

render

virtual void render	(	uint8_t *	ptr ,
		int	x ,
		int	xAdjust ,
		int	y ,
		unsigned	count ,
		const uint8_t *	covers
		)

Paint a designated part of the RenderingBuffer with respect to the amount of coverage of each pixel given by the parameter covers.

The cover is the alpha for each pixel, which is what makes it possible to have smooth anti-aliased edges on the shapes drawn with CanvasWidgetRenderer.

Parameters:

ptr	Pointer to the row in the RenderingBuffer.
x	The x coordinate.
xAdjust	The minor adjustment of x (used when a pixel is smaller than a byte to specify that the ptr should have been advanced "xAdjust" pixels futher into the byte).
y	The y coordinate.
count	Number of pixels to fill.
covers	The coverage in of each pixel.

Note

The implementation of render() in the AbstractPainter classes is a generic (i.e. slow) implementation that should be completely implemented in subclasses of AbstractPainter for better performance.

Reimplements: touchgfx::AbstractPainterGRAY4::render

setBitmap

void setBitmap	(	const Bitmap &	bmp	)

Sets a bitmap to be used when drawing the CanvasWidget.

Parameters:

bmp	The bitmap.

Protected Functions Documentation

renderInit

virtual bool renderInit	(			)

Initialize rendering of a single scan line of pixels for the render.

If renderInit returns false, the scanline will not be rendered.

Returns:

true if it succeeds, false if it fails.

Reimplements: touchgfx::AbstractPainterGRAY4::renderInit

renderNext

virtual bool renderNext	(	uint8_t &	gray ,
		uint8_t &	alpha
		)

Get the color of the next pixel in the scan line to blend into the framebuffer.

Parameters:

gray	The gray color (0-15).
alpha	The alpha.

Returns:

true if the pixel should be painted, false otherwise.

Reimplements: touchgfx::AbstractPainterGRAY4::renderNext

Protected Attributes Documentation

bitmap

Bitmap bitmap

The bitmap to be used when painting.

bitmapAlphaPointer

const uint8_t * bitmapAlphaPointer

Pointer to the bitmap alpha data for GRAY4.

bitmapGRAY4Pointer

const uint8_t * bitmapGRAY4Pointer

Pointer to the bitmap (GRAY4)

bitmapRectToFrameBuffer

Rect bitmapRectToFrameBuffer

Bitmap rectangle translated to framebuffer coordinates.