PainterRGB888LinearGradient

touchgfx/widgets/canvas/PainterRGB888LinearGradient.hpp

An abstract class for creating painter classes for drawing canvas widgets. All canvas widgets need a painter to fill the shape drawn with a CanvasWidgetRenderer. The painter must provide the color of a pixel on a given coordinate, which will the be blended into the framebuffer depending on the position of the canvas widget and the transparency of the given pixel.

Inherits from: AbstractPainterLinearGradient, AbstractPainter

Public Functions


virtual void	paint(uint8_t * destination, int16_t offset, int16_t widgetX, int16_t widgetY, int16_t count, uint8_t alpha) const
	Paints a streak of pixels (all with the same alpha) in the framebuffer.

virtual void	tearDown() const
	This function is called after all paint operation have finished.

virtual	~PainterRGB888LinearGradient()
	Destructor.

Additional inherited members

Public Functions inherited from AbstractPainterLinearGradient


	AbstractPainterLinearGradient()
	Constructor.

void	setGradientEndPoints(float startX, float startY, float endX, float endY, float width, float height, const Matrix3x3 & m)
	Set the gradient line.

void	setGradientTexture(const uint32_t * tex, bool solid)
	Set the 1024x1 texture used to color this texture.

virtual	~AbstractPainterLinearGradient()
	Destructor.

Protected Attributes inherited from AbstractPainterLinearGradient


float	clOffset
	Vertical offset for line with first color.

float	clSlope
	Slope of lines with same color.

int16_t	coord0
	The gradient line start.

int16_t	coord1
	The gradient line end.

float	deltaColor
	Color increment when moving 1 pixel horizontally.

float	horizontalDistance
	Horizontal distance between pixels with the first color and the last color.

bool	isHorizontal
	True if the gradient is horizontal (y0 == y1).

bool	isSolid
	True if all the gradient colors are solid.

bool	isVertical
	True if the gradient is vertical (x0 == x1).

const uint32_t *	texture
	The gradient color texture 1 x 1024.

Public Functions inherited from AbstractPainter


	AbstractPainter()
	Initializes a new instance of the AbstractPainter class.

void	framebufferToDisplay(int16_t & widgetX, int16_t & widgetY) const
	Convert Framebuffer widget coordinates to display widget coordinates.

virtual HAL::RenderingMethod	getRenderingMethod() const
	Return the applicable rendering method of the painter.

virtual bool	setup(const Rect & widgetRect) const
	This function is called before any actual paint operation is started.

virtual	~AbstractPainter()
	Finalizes an instance of the AbstractPainter class.

Protected Functions inherited from AbstractPainter


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	widgetWidth
	The width of the widget on screen, used by framebufferToDisplay()

Public Functions Documentation

paint


virtual void paint	(	uint8_t *	destination ,	const
		int16_t	offset ,	const
		int16_t	widgetX ,	const
		int16_t	widgetY ,	const
		int16_t	count ,	const
		uint8_t	alpha	const
		)	const

Paints a streak of pixels (all with the same alpha) in the framebuffer.

The first pixel to paint is at 'offset' relative to 'destination' (to be able to support 1bpp, 2bpp and 4bpp). The first pixel to paint is at the given 'widgetX', 'widgetY' coordinate. The number of pixels to paint is 'count' and the alpha to apply is 'alpha'.

Note that the widgetX, widgetY is relative to the widget in the framebuffer, not the display. To convert the coordinate to display widget coordinates, use framebufferToDisplay().

Parameters:


destination	If non-null, the pointer.
offset	The offset to add to the destination.
widgetX	The widget x coordinate.
widgetY	The widget y coordinate.
count	Number of pixels.
alpha	The alpha of the pixels.

tearDown


virtual void tearDown	(			)	const

This function is called after all paint operation have finished.

This allows the painter to close down dma queues etc. This happens after the last scan line segment has been drawn.