Canvas Class Reference

Public Types
using	ImageStore = uint8_t[kImageHeight][kImageWidth]

Public Member Functions
	Canvas (Canvas const &other)=delete
	Canvas (Canvas &&other)=delete
Canvas &	operator= (Canvas const &other)=delete
Canvas &	operator= (Canvas &&other)=delete
ImageStore &	hackGetImageStore ()
	XXX: DO NOT USE THIS OUTSIDE OF THE CORE OLED CODE.
Rendering routines
void	clear ()
	Clear the entire image.
void	clearAreaExact (int32_t minX, int32_t minY, int32_t maxX, int32_t maxY)
void	drawPixel (int32_t x, int32_t y)
	Set a single pixel.
void	clearPixel (int32_t x, int32_t y)
	Clear a single pixel.
void	invertPixel (int32_t x, int32_t y)
	Invert a single pixel.
void	drawHorizontalLine (int32_t pixelY, int32_t startX, int32_t endX)
void	drawVerticalLine (int32_t pixelX, int32_t startY, int32_t endY)
void	drawLine (int32_t x0, int32_t y0, int32_t x1, int32_t y1, const DrawLineOptions &options={})
void	drawRectangle (int32_t minX, int32_t minY, int32_t maxX, int32_t maxY)
void	drawRectangleRounded (int32_t minX, int32_t minY, int32_t maxX, int32_t maxY, BorderRadius radius=SMALL)
void	drawCircle (int32_t centerX, int32_t centerY, int32_t radius, std::optional< int32_t > min_x=std::nullopt, std::optional< int32_t > max_x=std::nullopt)
void	clearCircle (int32_t centerX, int32_t centerY, int32_t radius, std::optional< int32_t > min_x=std::nullopt, std::optional< int32_t > max_x=std::nullopt)
void	drawString (std::string_view str, int32_t pixelX, int32_t pixelY, int32_t textWidth, int32_t textHeight, int32_t scrollPos=0, int32_t endX=OLED_MAIN_WIDTH_PIXELS, bool useTextWidth=false)
void	drawStringCentred (char const *string, int32_t pixelY, int32_t textWidth, int32_t textHeight, int32_t centrePos=OLED_MAIN_WIDTH_PIXELS/2)
void	drawStringCentered (char const *string, int32_t startX, int32_t startY, int32_t textSpacingX, int32_t textSpacingY, int32_t totalWidth)
void	drawStringCentered (StringBuf &stringBuf, int32_t startX, int32_t startY, int32_t textSpacingX, int32_t textSpacingY, int32_t totalWidth)
void	drawStringCentredShrinkIfNecessary (char const *string, int32_t pixelY, int32_t textWidth, int32_t textHeight)
void	drawStringAlignRight (char const *string, int32_t pixelY, int32_t textWidth, int32_t textHeight, int32_t rightPos=OLED_MAIN_WIDTH_PIXELS)
void	drawChar (uint8_t theChar, int32_t pixelX, int32_t pixelY, int32_t textWidth, int32_t textHeight, int32_t scrollPos=0, int32_t endX=OLED_MAIN_WIDTH_PIXELS)
	Draw a single character.
int32_t	getCharIndex (uint8_t theChar)
int32_t	getCharWidthInPixels (uint8_t theChar, int32_t textHeight)
int32_t	getCharSpacingInPixels (uint8_t theChar, int32_t textHeight, bool isLastChar)
int32_t	getStringWidthInPixels (char const *string, int32_t textHeight)
void	drawGraphicMultiLine (uint8_t const *graphic, int32_t startX, int32_t startY, int32_t width, int32_t height=8, int32_t numBytesTall=1, bool reversed=false)
void	drawIcon (const Icon &icon, int32_t x, int32_t y, bool reversed=false)
void	drawIconCentered (const Icon &icon, int32_t startX, int32_t totalWidth, int32_t y, bool reversed=false)
void	drawScreenTitle (std::string_view text, bool drawSeparator=true)
void	invertArea (int32_t xMin, int32_t width, int32_t startY, int32_t endY)
void	invertAreaRounded (int32_t xMin, int32_t width, int32_t startY, int32_t endY, BorderRadius radius=SMALL)
void	invertLeftEdgeForMenuHighlighting (int32_t xMin, int32_t width, int32_t startY, int32_t endY)
	inverts just the left edge

Static Public Attributes
static constexpr uint32_t	kImageHeight = OLED_MAIN_HEIGHT_PIXELS >> 3
	Height of the image in bytes.
static constexpr uint32_t	kImageWidth = OLED_MAIN_WIDTH_PIXELS
	Width of the image in pixels.

Private Attributes
uint8_t	image_ [kImageHeight][kImageWidth]

Member Function Documentation

clearAreaExact()

void Canvas::clearAreaExact	(	int32_t	minX,
		int32_t	minY,
		int32_t	maxX,
		int32_t	maxY )

Clear only a subset of the image

Parameters

minX	minimum X coordinate, inclusive
minY	minimum Y coordinate, inclusive
maxX	maximum X coordinate, inclusive
maxY	maximum Y coordinate, exclusive

clearCircle()

void Canvas::clearCircle	(	int32_t	centerX,
		int32_t	centerY,
		int32_t	radius,
		std::optional< int32_t >	min_x = std::nullopt,
		std::optional< int32_t >	max_x = std::nullopt )

Clear a circle using Bresenham algorithm

Parameters

centerX	Center X coordinate
centerY	Center Y coordinate
radius	Circle radius
min_x	Optional minimum X boundary
max_x	Optional maximum X boundary

drawCircle()

void Canvas::drawCircle	(	int32_t	centerX,
		int32_t	centerY,
		int32_t	radius,
		std::optional< int32_t >	min_x = std::nullopt,
		std::optional< int32_t >	max_x = std::nullopt )

Draw a circle using Bresenham algorithm

Parameters

centerX	Center X coordinate
centerY	Center Y coordinate
radius	Circle radius
min_x	Optional minimum X boundary
max_x	Optional maximum X boundary

drawGraphicMultiLine()

void Canvas::drawGraphicMultiLine	(	uint8_t const *	graphic,
		int32_t	startX,
		int32_t	startY,
		int32_t	width,
		int32_t	height = 8,
		int32_t	numBytesTall = 1,
		bool	reversed = false )

Draw a "graphic".

The provided graphic array is used as a bit mask and added to the existing content.

Parameters

graphic	Pointer to the start of an array representing the graphic.
startX	X coodinate of the left edge of the graphic
startY	Y coordinate of the top of the graphic
width	Width of the graphic in pixels
height	Height of the graphic in pixels
numBytesTall	Number of bytes in the Y direction, determines the stride in the graphic array

drawHorizontalLine()

void Canvas::drawHorizontalLine	(	int32_t	pixelY,
		int32_t	startX,
		int32_t	endX )

Draw a horizontal line.

Parameters

pixelY	Y coordinate of the line to draw
startX	Starting X coordinate, inclusive
endY	Ending Y coordinate, inclusive

drawIcon()

void Canvas::drawIcon	(	const Icon &	icon,
		int32_t	x,
		int32_t	y,
		bool	reversed = false )

Draw an icon.

Parameters

icon	Reference to the icon
x	X coodinate of the left edge of the icon
y	Y coordinate of the top of the icon
reversed	Should reverse the icon horizontally

drawIconCentered()

void Canvas::drawIconCentered	(	const Icon &	icon,
		int32_t	startX,
		int32_t	totalWidth,
		int32_t	y,
		bool	reversed = false )

Draw an icon, centered between the provided startX and startX + totalWidth

Parameters

icon	Reference to the icon
startX	Beginning X coordinate for center calculation
totalWidth	Total width for center calculation
y	Y coordinate of the top of the icon
reversed	Should reverse the icon horizontally

drawLine()

void Canvas::drawLine	(	int32_t	x0,
		int32_t	y0,
		int32_t	x1,
		int32_t	y1,
		const DrawLineOptions &	options = {} )

Draw a line using Bresenham algorithm

Parameters

x0	Start X coordinate of the line
y0	Start Y coordinate of the line
x1	End X coordinate of the line
y1	End Y coordinate of the line
options	Draw options

drawRectangle()

void Canvas::drawRectangle	(	int32_t	minX,
		int32_t	minY,
		int32_t	maxX,
		int32_t	maxY )

Draw a 1-px wide rectangle.

Parameters

minX	Minimum X coordinate, inclusive
minY	Minimum Y coordinate, inclusive
maxX	Maximum X coordinate, inclusive
maxY	Maximum Y coordinate, inclusive

drawRectangleRounded()

void Canvas::drawRectangleRounded	(	int32_t	minX,
		int32_t	minY,
		int32_t	maxX,
		int32_t	maxY,
		BorderRadius	radius = SMALL )

Draw a 1-px wide rectangle with rounded corners

Parameters

minX	Minimum X coordinate, inclusive
minY	Minimum Y coordinate, inclusive
maxX	Maximum X coordinate, inclusive
maxY	Maximum Y coordinate, inclusive

drawScreenTitle()

void Canvas::drawScreenTitle	(	std::string_view	title,
		bool	drawSeparator = true )

Draw a screen title and underline it.

Parameters

text	Title text

drawString()

void Canvas::drawString	(	std::string_view	str,
		int32_t	pixelX,
		int32_t	pixelY,
		int32_t	textWidth,
		int32_t	textHeight,
		int32_t	scrollPos = 0,
		int32_t	endX = OLED_MAIN_WIDTH_PIXELS,
		bool	useTextWidth = false )

Draw a string

Parameters

str	The string
pixelX	X coordinate of the left side of the string
pixelY	Y coordinate of the top side of the string
textWidth	Base width in pixels of each character
textHeight	Height in pixels of each character
scrollPos	Offset in pixels representing how far the text has scrolled from the left.
endX	Maximum X coordinate after which we bail out. N.B. this means the actual maximum X coordinate rendered is endX + textWidth, as the individual character rendering work can overshoot.

drawStringAlignRight()

void Canvas::drawStringAlignRight	(	char const *	string,
		int32_t	pixelY,
		int32_t	textWidth,
		int32_t	textHeight,
		int32_t	rightPos = OLED_MAIN_WIDTH_PIXELS )

Draw a string, aligned to the right.

Parameters

string	A null-terminated C string
pixelY	The Y coordinate of the top of the string
textWidth	The width for each character in the string
textHeight	The height for each character in the string
rightPos	X coordinate, exclusive, of the rightmost pixel to use for the string

drawStringCentered() [1/2]

void Canvas::drawStringCentered	(	char const *	string,
		int32_t	startX,
		int32_t	startY,
		int32_t	textSpacingX,
		int32_t	textSpacingY,
		int32_t	totalWidth )

Draw a string, centered between the provided startX and startX + totalWidth

Parameters

string	A null-terminated C string
startX	Beginning X coordinate for center calculation
startY	Y coordinate of the top side of the string
textSpacingX	Base width in pixels of each character
textSpacingY	Height in pixels of each character
totalWidth	Total width for center calculation

drawStringCentered() [2/2]

void Canvas::drawStringCentered	(	StringBuf &	stringBuf,
		int32_t	startX,
		int32_t	startY,
		int32_t	textSpacingX,
		int32_t	textSpacingY,
		int32_t	totalWidth )

Draw a string, centered between the provided startX and startX + totalWidth

Parameters

stringBuf	A string buffer
startX	Beginning X coordinate for center calculation
startY	Y coordinate of the top side of the string
textSpacingX	Base width in pixels of each character
textSpacingY	Height in pixels of each character
totalWidth	Total width for center calculation

drawStringCentred()

void Canvas::drawStringCentred	(	char const *	string,
		int32_t	pixelY,
		int32_t	textWidth,
		int32_t	textHeight,
		int32_t	centrePos = OLED_MAIN_WIDTH_PIXELS / 2 )

Draw a string, centered at the provided location.

Parameters

string	A null-terminated C string
pixelY	Y coordinate of the top side of the string
textWidth	Base width in pixels of each character
textHeight	Height in pixels of each character
scrollPos	Offset in pixels representing how far the text has scrolled from the left.
endX	Maximum X coordinate after which we bail out. N.B. this means the actual maximum X coordinate rendered is endX + textWidth, as the individual character rendering work can overshoot.

drawStringCentredShrinkIfNecessary()

void Canvas::drawStringCentredShrinkIfNecessary	(	char const *	string,
		int32_t	pixelY,
		int32_t	textWidth,
		int32_t	textHeight )

Draw a string, reducing its height so the string fits within the specified width

Parameters

string	A null-terminated C string
pixelY	The Y coordinate of the top of the string
textWidth	Requested width for each character in the string
textHeight	Requested height for each character in the string

Draw a string, reducing its height so the string fits within the specified width

Parameters

string	A null-terminated C string
textWidth	Requested width for each character in the string
textHeight	Requested height for each character in the string

drawVerticalLine()

void Canvas::drawVerticalLine	(	int32_t	pixelX,
		int32_t	startY,
		int32_t	endY )

Draw a vertical line.

Parameters

pixelX	X coordinate of the line
startY	Y coordinate of the line, inclusive
endY	Y coordinate of the line, inclusive

getCharIndex()

int32_t Canvas::getCharIndex

(

uint8_t

theChar

)

Returns index for character so it can be looked up

Parameters

theChar

A single character

getCharSpacingInPixels()

int32_t Canvas::getCharSpacingInPixels	(	uint8_t	theChar,
		int32_t	textHeight,
		bool	isLastChar )

Returns spacing in pixels between characters drawn in a string

Parameters

theChar	A single character
textHeight	The height of the character (to distinguish between non-bold and bold characters)
isLastChar	a boolean to specify whether any char's follow this char

getCharWidthInPixels()

int32_t Canvas::getCharWidthInPixels	(	uint8_t	theChar,
		int32_t	textHeight )

Return width of a single character with a given character height

Parameters

theChar	A single character
textHeight	The height of the character

getStringWidthInPixels()

int32_t Canvas::getStringWidthInPixels	(	char const *	string,
		int32_t	textHeight )

Returns width of a string in pixels

Parameters

string	A null-terminated C string
textHeight	The height for each character in the string

invertArea()

void Canvas::invertArea	(	int32_t	xMin,
		int32_t	width,
		int32_t	startY,
		int32_t	endY )

Invert an area of the canvas.

Parameters

xMin	Minimum X coordinate, inclusive
width	Width of the region to invert. End coordinate is excluded.
startY	Minimum Y coordinate, inclusive
endY	Maximum Y coordinate, inclusive

invertAreaRounded()

void Canvas::invertAreaRounded	(	int32_t	xMin,
		int32_t	width,
		int32_t	startY,
		int32_t	endY,
		BorderRadius	radius = SMALL )

Invert an area of the canvas with rounded corners

Parameters

xMin	Minimum X coordinate, inclusive
width	Width of the region to invert. End coordinate is excluded.
startY	Minimum Y coordinate, inclusive
endY	Maximum Y coordinate, inclusive

invertLeftEdgeForMenuHighlighting()

void Canvas::invertLeftEdgeForMenuHighlighting	(	int32_t	xMin,
		int32_t	width,
		int32_t	startY,
		int32_t	endY )

inverts just the left edge

Invert just the left edge of the canvas.

Parameters

xMin	Minimum X coordinate, inclusive
width	Width of the region to invert. End coordinate is excluded.
startY	Minimum Y coordinate, inclusive
endY	Maximum Y coordinate, inclusive

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The documentation for this class was generated from the following files:

• src/deluge/hid/display/oled_canvas/canvas.h
• src/deluge/hid/display/oled_canvas/canvas.cpp