daisy::OneBitGraphicsDisplayImpl< ChildType > Class Template Reference

Detailed Description

template<class ChildType>
class daisy::OneBitGraphicsDisplayImpl< ChildType >

This class is intended as a intermediary class for your actual implementation of the OneBitGraphicsDisplay interface. It uses the CRTP design pattern where the template argument is the child class. It provides implementations for most of the functions, except DrawPixel(), Update() and Fill(), which you'll have to provide in your child class. The main goal of this class is to provide common drawing functions without relying on massive amounts of virtual function calls that would result in a performance loss. To achieve this, any drawing function that is implemented here and internally calls other drawing functions (e.g. DrawRect() which internally calls DrawPixel() and DrawLine()) makes these calls via the qualified name of these functions to explicitly suppress the virtual dispatch mechanism like this:

ChildType::DrawPixel(...); // no virtual function call; direct call into the child class function

To create a custom OneBitGraphicsDisplay implementation, you can A) inherit from OneBitGraphicsDisplay directly and provide all the drawing functions yourself B) Inherit from OneBitGraphicsDisplayImpl and only provide DrawPixel(), Fill() and Update() like this:

class MyDisplayClass : public OneBitGraphicsDisplayImpl<MyDisplayClass> { public: void Fill() override { ... }; void DrawPixel(uint_fast8_t x, uint_fast8_t y, bool on) override { ... }; void Update() override { ... } };

#include <display.h>

Inheritance diagram for daisy::OneBitGraphicsDisplayImpl< ChildType >:

Public Member Functions
	OneBitGraphicsDisplayImpl ()
virtual	~OneBitGraphicsDisplayImpl ()
void	DrawLine (uint_fast8_t x1, uint_fast8_t y1, uint_fast8_t x2, uint_fast8_t y2, bool on) override
void	DrawRect (uint_fast8_t x1, uint_fast8_t y1, uint_fast8_t x2, uint_fast8_t y2, bool on, bool fill=false) override
void	DrawArc (uint_fast8_t x, uint_fast8_t y, uint_fast8_t radius, int_fast16_t start_angle, int_fast16_t sweep, bool on) override
char	WriteChar (char ch, FontDef font, bool on) override
char	WriteString (const char *str, FontDef font, bool on) override
Rectangle	WriteStringAligned (const char *str, const FontDef &font, Rectangle boundingBox, Alignment alignment, bool on) override
Public Member Functions inherited from daisy::OneBitGraphicsDisplay
	OneBitGraphicsDisplay ()
virtual	~OneBitGraphicsDisplay ()
virtual uint16_t	Height () const =0
virtual uint16_t	Width () const =0
Rectangle	GetBounds () const
size_t	CurrentX ()
size_t	CurrentY ()
virtual void	Fill (bool on)=0
virtual void	DrawPixel (uint_fast8_t x, uint_fast8_t y, bool on)=0
void	DrawRect (const Rectangle &rect, bool on, bool fill=false)
void	DrawCircle (uint_fast8_t x, uint_fast8_t y, uint_fast8_t radius, bool on)
void	SetCursor (uint16_t x, uint16_t y)
virtual void	Update ()=0

Additional Inherited Members
Protected Attributes inherited from daisy::OneBitGraphicsDisplay
uint16_t	currentX_
uint16_t	currentY_

Constructor & Destructor Documentation

OneBitGraphicsDisplayImpl()

template<class ChildType >

daisy::OneBitGraphicsDisplayImpl< ChildType >::OneBitGraphicsDisplayImpl ( )

inline

~OneBitGraphicsDisplayImpl()

template<class ChildType >

virtual daisy::OneBitGraphicsDisplayImpl< ChildType >::~OneBitGraphicsDisplayImpl ( )

inlinevirtual

Member Function Documentation

DrawArc()

template<class ChildType >

void daisy::OneBitGraphicsDisplayImpl< ChildType >::DrawArc ( uint_fast8_t x, uint_fast8_t y, uint_fast8_t radius, int_fast16_t start_angle, int_fast16_t sweep, bool on )

inlineoverridevirtual

Draws an arc around the specified coordinate

Parameters

x	x Coordinate of the center of the arc
y	y Coordinate of the center of the arc
radius	radius of the arc
start_angle	angle where to start the arc
sweep	total angle of the arc
on	on or off

Implements daisy::OneBitGraphicsDisplay.

DrawLine()

template<class ChildType >

void daisy::OneBitGraphicsDisplayImpl< ChildType >::DrawLine ( uint_fast8_t x1, uint_fast8_t y1, uint_fast8_t x2, uint_fast8_t y2, bool on )

inlineoverridevirtual

Draws a line from (x1, y1) to (y1, y2)

Parameters

x1	x Coordinate of the starting point
y1	y Coordinate of the starting point
x2	x Coordinate of the ending point
y2	y Coordinate of the ending point
on	on or off

Implements daisy::OneBitGraphicsDisplay.

DrawRect()

template<class ChildType >

void daisy::OneBitGraphicsDisplayImpl< ChildType >::DrawRect ( uint_fast8_t x1, uint_fast8_t y1, uint_fast8_t x2, uint_fast8_t y2, bool on, bool fill = false )

inlineoverridevirtual

Draws a rectangle based on two coordinates.

Parameters

x1	x Coordinate of the first point
y1	y Coordinate of the first point
x2	x Coordinate of the second point
y2	y Coordinate of the second point
on	on or off
fill	fill the rectangle or draw only the outline

Implements daisy::OneBitGraphicsDisplay.

WriteChar()

template<class ChildType >

char daisy::OneBitGraphicsDisplayImpl< ChildType >::WriteChar ( char ch, FontDef font, bool on )

inlineoverridevirtual

Writes the character with the specific FontDef to the display buffer at the current Cursor position.

Parameters

ch	character to be written
font	font to be written in
on	on or off

Returns

&

Implements daisy::OneBitGraphicsDisplay.

WriteString()

template<class ChildType >

char daisy::OneBitGraphicsDisplayImpl< ChildType >::WriteString ( const char * str, FontDef font, bool on )

inlineoverridevirtual

Similar to WriteChar, except it will handle an entire String. Wrapping does not happen automatically, so the width of the string must be kept within the dimensions of the screen.

Parameters

str	string to be written
font	font to use
on	on or off

Returns

&

Implements daisy::OneBitGraphicsDisplay.

WriteStringAligned()

template<class ChildType >

Rectangle daisy::OneBitGraphicsDisplayImpl< ChildType >::WriteStringAligned ( const char * str, const FontDef & font, Rectangle boundingBox, Alignment alignment, bool on )

inlineoverridevirtual

Similar to WriteString but justified within a bounding box.

Parameters

str	string to be written
font	font to use
boundingBox	the bounding box to draw the text in
alignment	the alignment to use
on	on or off

Returns

The rectangle that was drawn to

Implements daisy::OneBitGraphicsDisplay.

---

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

• src/hid/disp/display.h