TextWidget Class Reference

a dedicated class for text frame only More...

#include <widget.h>

Inheritance diagram for TextWidget:

Collaboration diagram for TextWidget:

Public Member Functions
struct_ConfigTextWidget	get_text_frame_config ()
	Get the text frame config object.
	TextWidget (GraphicDisplayDevice *graphic_display_screen, struct_ConfigTextWidget text_cfg, CanvasFormat canvas_format, Model *displayed_object=nullptr)
	The max number of line with respect to frame height and font height.
	TextWidget (GraphicDisplayDevice *graphic_display_screen, struct_ConfigTextWidget text_cfg, CanvasFormat canvas_format, size_t frame_width, size_t frame_height, Model *displayed_object=nullptr)
	Construct a new Text Widget object.
virtual	~TextWidget ()
	the destructor of TextWidget
void	update_text_frame_size (const unsigned char *font)
	Compute the text size in column x line according to the size of the font and the size of the frame in pixel. Delete the previous text buffer if any and create a new buffer.
void	clear_text_buffer ()
	et text buffer memory to "0" and set character current line and column to 0
void	update_canvas_buffer_size (const unsigned char *font)
	compute canvas width and height according to the size of the text (column x line ) and the size of the bitmap font. Delete the previous pixel buffer if any and create a new buffer.
void	write ()
	process characters in the internal text buffer and draw it into the pixel buffer.
void	write (const char *c_str)
	process the string c_str and then draw each character into the pixel buffer, without using the text buffer.
void	process_char (char character)
	interpret the character and draw it into the pixel buffer at the current line and column character position.
void	next_line ()
	character line steps one position downward.
void	next_char ()
	character column steps forward one position forward.
void	draw ()
	we need draw() to be compliant with the pure virtual draw() inherited from Widget.
void	draw_border (ColorIndex color=ColorIndex::WHITE)
	draw a one-pixel width around the the frame
Public Member Functions inherited from GraphicWidget
void	update_widget_anchor (uint8_t x, uint8_t y)
	Modify the anchor of the widget on the display screen.
void	show ()
	A short way to call GraphicDisplayDevice::show(&canvas, anchor x, anchor y)
void	send_image_to_DisplayGateKeeper (QueueHandle_t display_queue, SemaphoreHandle_t sending_done)
	used with FreeRTOS. send the widget data_to_display structure to the task in charge of the display management
	GraphicWidget (GraphicDisplayDevice *graphic_display_screen, struct_ConfigGraphicWidget graph_cfg, CanvasFormat canvas_format, Model *displayed_object=nullptr)
	Construct a new Graphic Widget object.
	GraphicWidget (GraphicDisplayDevice *graphic_display_screen, struct_ConfigTextWidget text_cfg, CanvasFormat canvas_format, Model *displayed_object=nullptr)
	Construct a new Graphic Widget object from the TextWidget Constructor.
	GraphicWidget (GraphicDisplayDevice *graphic_display_screen, struct_ConfigTextWidget text_cfg, CanvasFormat canvas_format, size_t frame_width, size_t frame_height, Model *displayed_object=nullptr)
	Construct a new Graphic Widget object from the TextWidget Constructor.
virtual	~GraphicWidget ()
	Destroy the Widget object.
struct_ConfigGraphicWidget	get_graph_frame_config ()
	Get the graphic frame config object.
void	hline (uint8_t x, uint8_t y, size_t w, ColorIndex color=ColorIndex::WHITE)
	Draw a color horizontal line, starting at frame position (x,y), on w number of pixel.
void	vline (uint8_t x, uint8_t y, size_t h, ColorIndex color=ColorIndex::WHITE)
	Draw a color vertical line, starting at frame position (x,y), on w number of pixel.
void	line (int x0, int y0, int x1, int y1, ColorIndex color=ColorIndex::WHITE)
	Draw a color line, starting at frame position (x0,y0), ending at frame position (x1,y1)
void	rect (uint8_t start_x, uint8_t start_y, size_t w, size_t h, bool fill=false, ColorIndex color=ColorIndex::WHITE)
	Draw a rectangle, starting at frame position (x,y), w wide and h high.
void	circle (int radius, int x_center, int y_center, bool fill=false, ColorIndex color=ColorIndex::WHITE)
	draw a cercle of size radius, centered at (x_center, y_center) https://fr.wikipedia.org/wiki/Algorithme_de_trac%C3%A9_d%27arc_de_cercle_de_Bresenham https://en.wikipedia.org/wiki/Midpoint_circle_algorithm procédure tracerCercle (entier rayon, entier x_centre, entier y_centre) déclarer entier x, y, m ; x ← 0 ; y ← rayon ; // on se place en haut du cercle m ← 5 - 4*rayon ; // initialisation Tant que x <= y // tant qu'on est dans le second octant tracerPixel( x+x_centre, y+y_centre ) ; tracerPixel( y+x_centre, x+y_centre ) ; tracerPixel( -x+x_centre, y+y_centre ) ; tracerPixel( -y+x_centre, x+y_centre ) ; tracerPixel( x+x_centre, -y+y_centre ) ; tracerPixel( y+x_centre, -x+y_centre ) ; tracerPixel( -x+x_centre, -y+y_centre ) ; tracerPixel( -y+x_centre, -x+y_centre ) ; si m > 0 alors //choix du point F y ← y - 1 ; m ← m - 8*y ; fin si ; x ← x + 1 ; m ← m + 8*x + 4 ; fin tant que ; fin de procédure ;
Public Member Functions inherited from Widget
	Widget (Model *actual_displayed_model, DisplayDevice *graphic_display_device=nullptr)
	contructor for generic widget
void	add_widget (Widget *_sub_widget)
	add sub_widget to the current widget
void	set_display_device (DisplayDevice *_new_display_device)
	Set the display screen object.

Public Attributes
uint8_t	number_of_column {0}
	The max number of line with respect to frame height and font height.
uint8_t	number_of_line {0}
	The max number of column with respect to frame width and font width.
size_t	text_buffer_size
	size of the buffer that contains text as string of characters.
char *	text_buffer = nullptr
	the buffer where text are written
Public Attributes inherited from GraphicWidget
Canvas *	canvas
	the associated canvas in which the widget writes text and draws graphics
uint8_t	widget_anchor_x
	location in x of the widget within the hosting framebuffer
uint8_t	widget_anchor_y
	location in y of the widget within the hosting framebuffer
struct_DataToShow	data_to_display
	the data structure used to send the canvas to the display task when a FreeRTOS queue is used.

Protected Member Functions
void	create_text_buffer ()
	create text buffer and delete the old one if already existing
Protected Member Functions inherited from GraphicWidget
void	clear_widget ()
	fill the graphic pixel buffer with 0x00.
virtual void	get_value_of_interest ()=0
	A pure virtual method that results in the transfer of the displayed values of the displayed model to the widget.

Additional Inherited Members
Protected Attributes inherited from GraphicWidget
bool	widget_with_border {false}
	if true, the widget is surrounded by a one-pixel border
size_t	widget_width {128}
	As a widget can be surrounded by a border, the actual widget width is not the associated framebuffer width.
size_t	widget_height {8}
	As a widget can be surrounded by a border, the actual widget height is not the associated framebuffer height.
uint8_t	widget_start_x
	this is the actual horizontal start of the widget drawing area, taken into account the presence of border.
uint8_t	widget_start_y
	this is the actual vertical start of the widget drawing area, taken into account the presence of border.
uint8_t	widget_border_width
	this is the border size of the widget. 0 if no border, 1 if border
Protected Attributes inherited from Widget
DisplayDevice *	display_device {nullptr}
	the display device where the attached to the frame buffer
Model *	actual_displayed_model {nullptr}
	a pointer to the Model actually displayed by the widget
std::vector< Widget * >	widgets
	A widget can be composed by several widgets.

Detailed Description

a dedicated class for text frame only

Constructor & Destructor Documentation

TextWidget() [1/2]

TextWidget::TextWidget	(	GraphicDisplayDevice *	graphic_display_screen,
		struct_ConfigTextWidget	text_cfg,
		CanvasFormat	canvas_format,
		Model *	displayed_object = nullptr )

The max number of line with respect to frame height and font height.

Construct a new Text Widget object

Note

USAGE: when the text frame is defined by the number of characters width and height.

Parameters

graphic_display_screen	The display device on which the widget is drawn
text_cfg	the configuration data for the textual frame
canvas_format	the format of the associated canvas (see CanvasFormat)
displayed_object	the displayed model of the widget. Default to nullptr

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TextWidget() [2/2]

TextWidget::TextWidget	(	GraphicDisplayDevice *	graphic_display_screen,
		struct_ConfigTextWidget	text_cfg,
		CanvasFormat	canvas_format,
		size_t	frame_width,
		size_t	frame_height,
		Model *	displayed_object = nullptr )

Construct a new Text Widget object.

Note

USAGE: when the text frame is defined by the frame size width and height in pixel.

Parameters

graphic_display_screen	The display device on which the widget is drawn
text_cfg	the configuration data for the textual frame
canvas_format	the format of the associated canvas (see CanvasFormat)
frame_width	the frame size width
frame_height	the frame size height
displayed_object	the displayed model of the widget. Default to nullptr

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Member Function Documentation

draw()

void TextWidget::draw ( )

virtual

we need draw() to be compliant with the pure virtual draw() inherited from Widget.

Note

USAGE: It is called by the draw_refresh method of the Model The draw() member calls the following method : 1) clear_text_buffer(); 2) get_value_of_interest(); 3) write(); – transfer characters in text_buffer to pixels in the pixel_buffer 4) draw_border(); 5) show();

Implements Widget.

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draw_border()

void TextWidget::draw_border ( ColorIndex color = ColorIndex::WHITE )

virtual

draw a one-pixel width around the the frame

Note

This border can overwrite the characters! To be improve with the use of pixel frame memory not based on byte page such as the OLED SSD1306.

Parameters

color

Reimplemented from GraphicWidget.

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get_text_frame_config()

struct_ConfigTextWidget TextWidget::get_text_frame_config

(

)

Get the text frame config object.

Returns

struct_ConfigTextFramebuffer

process_char()

void TextWidget::process_char

(

char

character

)

interpret the character and draw it into the pixel buffer at the current line and column character position.

Text wrapping is done if wrap flag is true. Character position steps forward according to auto_next_char flag.

Some special characters are processed:

• "LINE_FEED" (\n 0x0A) : line position steps forward, column position is set to 0.
• "BACKSPACE" (\b 0x08) : column position steps backward, a space (" ") character is overwritten.
• "FORM_FEED" (\f 0x0C) : the text buffer is cleared.
• "CARRIAGE_RETURN" (\r 0x0D) : column position is set to 0.
• "HORIZONTAL_TAB" (\t 0x09) : " " characters are added according to tab_size configuration value.

  Parameters

  character

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update_canvas_buffer_size()

void TextWidget::update_canvas_buffer_size

(

const unsigned char *

font

)

compute canvas width and height according to the size of the text (column x line ) and the size of the bitmap font. Delete the previous pixel buffer if any and create a new buffer.

Parameters

font	the new font

update_text_frame_size()

void TextWidget::update_text_frame_size

(

const unsigned char *

font

)

Compute the text size in column x line according to the size of the font and the size of the frame in pixel. Delete the previous text buffer if any and create a new buffer.

Parameters

font	the new font

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write() [1/2]

void TextWidget::write

(

)

process characters in the internal text buffer and draw it into the pixel buffer.

Note

USAGE: this is useful if we have to fill the text_buffer, e.g. with sprintf and formatted text.

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write() [2/2]

void TextWidget::write

(

const char *

c_str

)

process the string c_str and then draw each character into the pixel buffer, without using the text buffer.

Parameters

c_str

A C_style character string.

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

• widget.h
• widget.cpp