Button

A button that can be clicked. Member of GUI classes Graphic group. More...

#include <Button.h>

Classes
struct	STYLE
	Button style information. More...

Public Member Functions
	Button ()
	Default constructor.
	Button (cv::Point startPoint, int height, cv::String text)
	Constructor. More...
void	draw (cv::Mat *img)
	Draws the button to the image matrix. More...
void	setStartPoint (cv::Point startPoint)
	Sets the topleft corner of the button. More...
void	checkClick (int x, int y)
	Checks if a mouse-click event happened inside the button. More...
int	getWidth ()
	Gets the width of the button. More...
bool	getClick ()
	Gets the button state. More...

Private Member Functions
void	roundedRectangle (cv::Mat *img, cv::Point topLeft, cv::Point bottomRight, const cv::Scalar lineColor, const cv::Scalar fillColor, const int thickness, const int cornerRadius)
	creates a rectangle with rounded corners More...

Private Attributes
cv::Point	startPoint
	X and Y coordinate of the topleft corner in pixels.
cv::Size	size
	Height and Width of the button in pixels.
cv::String	text
	Button Text.
bool	clicked
	Button state.
cv::Mat *	img
	Pointer to the img where the button should be drawn.
struct Button::STYLE	style
	button style information

Detailed Description

A button that can be clicked. Member of GUI classes Graphic group.

Constructor & Destructor Documentation

Button()

Button::Button	(	cv::Point	startPoint,
		int	height,
		cv::String	text
	)

Constructor.

Parameters

startPoint	X and Y coordinate of the topleft corner in pixels
height	Height of the button in pixels
text	Button text

                                                            {
    int baseline = 0;
    this->startPoint = startPoint;
    this->size = Size(getTextSize(text, style.fontFace, style.fontScale, 1, &baseline).width + 4, height);
    this->text = text;
    this->clicked = false;
};

Member Function Documentation

roundedRectangle()

void Button::roundedRectangle ( cv::Mat *  img, cv::Point  topLeft, cv::Point  bottomRight, const cv::Scalar  lineColor, const cv::Scalar  fillColor, const int  thickness, const int  cornerRadius  )

private

creates a rectangle with rounded corners

First draws the four edges, than draws the corners and last fills the rectangle.

Parameters

img	Pointer to the img where the rounded rectangle should be drawn
topLeft	X and Y coordinate of the topleft corner in pixels
bottomRight	X and Y coordinate of the bottomright corner in pixels
lineColor	color of the button edge(line)
fillColor	color of the button
thickness	line thickness
cornerRadius	size of the rounded corner radius in pixels

{
    /* corners:
        * p1 - p2
        * |     |
        * p4 - p3
        */
    Point p1 = topLeft;
    Point p2 = Point(bottomRight.x, topLeft.y);
    Point p3 = bottomRight;
    Point p4 = Point(topLeft.x, bottomRight.y);
 
    // draw straight lines
    line(*img, Point(p1.x + cornerRadius, p1.y), Point(p2.x - cornerRadius, p2.y), lineColor, thickness);
    line(*img, Point(p2.x, p2.y + cornerRadius), Point(p3.x, p3.y - cornerRadius), lineColor, thickness);
    line(*img, Point(p4.x + cornerRadius, p4.y), Point(p3.x - cornerRadius, p3.y), lineColor, thickness);
    line(*img, Point(p1.x, p1.y + cornerRadius), Point(p4.x, p4.y - cornerRadius), lineColor, thickness);
 
    // draw arcs
    ellipse(*img, p1 + Point(cornerRadius, cornerRadius), Size(cornerRadius, cornerRadius), 180.0, 0, 90, lineColor, thickness);
    ellipse(*img, p2 + Point(-cornerRadius, cornerRadius), Size(cornerRadius, cornerRadius), 270.0, 0, 90, lineColor, thickness);
    ellipse(*img, p3 + Point(-cornerRadius, -cornerRadius), Size(cornerRadius, cornerRadius), 0.0, 0, 90, lineColor, thickness);
    ellipse(*img, p4 + Point(cornerRadius, -cornerRadius), Size(cornerRadius, cornerRadius), 90.0, 0, 90, lineColor, thickness);
 
    //Fill the rectangle
    Point fillFrom(topLeft.x + 10, topLeft.y + 10);
    floodFill(*img, fillFrom, fillColor);
}

draw()

void Button::draw

(

cv::Mat *

img

)

Draws the button to the image matrix.

the color of the line is based on the button state. The text is always centered in the middle of the button.

Parameters

img	Pointer to the image where the button should be drawn

                          {
    int baseLine = 0;
    Scalar lColor;
    if (this->clicked)
        lColor = style.lineColorClicked;
    else
        lColor = style.lineColor;
 
    Size textSize = getTextSize(text, style.fontFace, style.fontScale, 1, &baseLine);
    roundedRectangle(img, startPoint, Point(startPoint.x + size.width, startPoint.y + size.height), lColor, style.fillColor, 1, 3);
    Point textOrg((startPoint.x + size.width / 2 - textSize.width / 2), (startPoint.y + size.height / 2 + textSize.height / 2));
    putText(*img, text, textOrg, style.fontFace, style.fontScale, style.fontColor, 1, 8);
 
}

setStartPoint()

void Button::setStartPoint

(

cv::Point

startPoint

)

Sets the topleft corner of the button.

is used to shift the startpoints of the buttons when creating the GUI.

Parameters

startPoint

X and Y coordinate of the topleft corner in pixels

                                           {
    this->startPoint = startPoint;
}

checkClick()

void Button::checkClick	(	int	x,
		int	y
	)

Checks if a mouse-click event happened inside the button.

Parameters

x	X-part of the mouse event Coordinate
y	Y-part of the mouse event Coordinate

                                    {
    //Check if x and y lie within the button
    if ((x >= startPoint.x) && (x <= startPoint.x + size.width) && (y >= startPoint.y) && (y <= startPoint.y + size.height)) {
        clicked = !clicked;
    }
}

getWidth()

int Button::getWidth

(

)

Gets the width of the button.

Returns

Width in pixels

                     {
    return size.width;
}

getClick()

bool Button::getClick

(

)

Gets the button state.

Returns

button state(Boolean)

                      {
    return clicked;
}