Class Picture

java.lang.Object
  Picture

public class Picture
extends Object

A picture from an image file.

Nested Class Summary

(package private) static class	Picture.Canvas
static class	Picture.Color

Constructor Summary

Picture()
Constructs a picture with no image.

Picture(String source)
Constructs an image from a given file or URL.

Method Summary

void	draw() Shows this picture on the canvas.
Picture.Color	getColorAt(int i) Gets the color of a pixel.
Picture.Color	getColorAt(int x, int y) Gets the color of a pixel.
double	getHeight() Gets the height of this picture.
double	getWidth() Gets the width of this picture.
double	getX() Gets the leftmost x-position of the shape.
double	getY() Gets the topmost y-position of the shape.
void	grow(double dw, double dh) Resizes this picture both horizontally and vertically.
void	load(String source) Loads a new image from a given file or URL.
void	paintShape(Graphics2D g2) Draws this shape.
void	pause() Pauses so that one can look at the picture.
void	pick() Displays a file chooser for picking a file, loads the picture from the file that the user selected, and pauses so that the user can see the loaded picture.
int	pixels() The number of pixels in this picture.
void	setColorAt(int x, int y, Picture.Color color) Sets the color of a pixel.
void	setColorAt(int i, Picture.Color color) Sets the color of a pixel.
void	translate(double dx, double dy) Moves this picture by a given amount.

Methods inherited from class

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Picture

public Picture()

Constructs a picture with no image.

Picture

public Picture(String source)

Constructs an image from a given file or URL.

Parameters:

source - the filename or URL

Method Detail

draw

public void draw()

Shows this picture on the canvas.

getColorAt

public Picture.Color getColorAt(int i)

Gets the color of a pixel.

Parameters:

i - the pixel index

Returns:

the color at pixel i

getColorAt

public Picture.Color getColorAt(int x,
                                int y)

Gets the color of a pixel.

Parameters:

x - the x-coordinate (column) of the pixel

y - the y-coordinate (row) of the pixel

color - the new color for the pixel

getHeight

public double getHeight()

Gets the height of this picture.

getWidth

public double getWidth()

Gets the width of this picture.

getX

public double getX()

Gets the leftmost x-position of the shape.

Returns:

the leftmost x-position

getY

public double getY()

Gets the topmost y-position of the shape.

Returns:

the topmost y-position

grow

public void grow(double dw,
                 double dh)

Resizes this picture both horizontally and vertically.

Parameters:

dw - the amount by which to resize the width on each side

dw - the amount by which to resize the height on each side

load

public void load(String source)

Loads a new image from a given file or URL.

Parameters:

source - the filename or URL

paintShape

public void paintShape(Graphics2D g2)

Draws this shape.

Parameters:

g2 - the graphics context

pause

public void pause()

Pauses so that one can look at the picture.

pick

public void pick()

Displays a file chooser for picking a file, loads the picture from the file that the user selected, and pauses so that the user can see the loaded picture.

pixels

public int pixels()

The number of pixels in this picture.

Returns:

the number of pixels

setColorAt

public void setColorAt(int x,
                       int y,
                       Picture.Color color)

Sets the color of a pixel.

Parameters:

x - the x-coordinate (column) of the pixel

y - the y-coordinate (row) of the pixel

the - color of the pixel at the given row and column

setColorAt

public void setColorAt(int i,
                       Picture.Color color)

Sets the color of a pixel.

Parameters:

i - the pixel index

color - the new color for the pixel

translate

public void translate(double dx,
                      double dy)

Moves this picture by a given amount.

Parameters:

dx - the amount by which to move in x-direction

dy - the amount by which to move in y-direction