AbstractPainterLinearGradient

touchgfx/widgets/canvas/AbstractPainterLinearGradient.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: AbstractPainter

Inherited by: PainterRGB565LinearGradient, PainterRGB888LinearGradient

Public Functions

	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

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.

Additional inherited members

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 void	paint(uint8_t * destination, int16_t offset, int16_t widgetX, int16_t widgetY, int16_t count, uint8_t alpha) const =0
	Paints a streak of pixels (all with the same alpha) in the framebuffer.
virtual bool	setup(const Rect & widgetRect) const
	This function is called before any actual paint operation is started.
virtual void	tearDown() const
	This function is called after all paint operation have finished.
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

AbstractPainterLinearGradient

AbstractPainterLinearGradient	(			)

Constructor.

setGradientEndPoints

void setGradientEndPoints	(	float	startX ,
		float	startY ,
		float	endX ,
		float	endY ,
		float	width ,
		float	height ,
		const Matrix3x3 &	m
		)

Set the gradient line.

First coordinate (startX, startY) specifies the position of the first color. Last coordinate (endX, endY) specifies the position of the last color.

Parameters:

startX	X coordinate of the gradient line start point.
startY	Y coordinate of the gradient line start point.
endX	X coordinate of the gradient line end point.
endY	Y coordinate of the gradient line end point.
width	Width of gradient.
height	Height of gradient.
m	Transformation.

setGradientTexture

void setGradientTexture	(	const uint32_t *	tex ,
		bool	solid
		)

Set the 1024x1 texture used to color this texture.

The texture is mapped to the gradient line (startX, startY) to (endX, endY).

The texture must be in ARGB8888 format.

Parameters:

tex	The gradient texture.
solid	True if all colors in the gradient are solid.

~AbstractPainterLinearGradient

virtual ~AbstractPainterLinearGradient	(			)

Destructor.

Protected Attributes Documentation

clOffset

float clOffset

Vertical offset for line with first color.

clSlope

float clSlope

Slope of lines with same color.

coord0

int16_t coord0

The gradient line start.

coord1

int16_t coord1

The gradient line end.

deltaColor

float deltaColor

Color increment when moving 1 pixel horizontally.

horizontalDistance

float horizontalDistance

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

isHorizontal

bool isHorizontal

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

isSolid

bool isSolid

True if all the gradient colors are solid.

isVertical

bool isVertical

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

texture

const uint32_t * texture

The gradient color texture 1 x 1024.