framebuffer

Class FrameBuffer

java.lang.Object

framebuffer.FrameBuffer

public class FrameBuffer
extends java.lang.Object

This FrameBuffer represents a two-dimensional array of pixel data. The data is stored as a one dimensional array in row-major order. The first row of data should be displayed as the top row of pixels in the image (or window).

The "viewport" is a two-dimensional sub array of this framebuffer. The viewport is represented by its upper-left-hand corner and its lower-right-hand corner.

Framebuffer and viewport coordinates act like Java Graphics coordinates; the positive x direction is to the right and the positive y direction is downward.

Field Summary

Fields

Modifier and Type	Field and Description
protected int[]	pixel_buffer

Constructor Summary

Constructors

Constructor and Description
FrameBuffer(int w, int h) Construct a FrameBuffer with the given dimensions.
FrameBuffer(java.lang.String inputFileName) Construct a FrameBuffer from a PPM image file.

Method Summary

Modifier and Type	Method and Description
void	clearFB(java.awt.Color c) Clear the framebuffer (set a background color).
void	clearVP(java.awt.Color c) Clear the viewport (set a background color).
FrameBuffer	convertBlue2FB() Convert the blue plane of the framebuffer into a framebuffer.
FrameBuffer	convertGreen2FB() Convert the green plane of the framebuffer into a framebuffer.
FrameBuffer	convertRed2FB() Convert the red plane of the framebuffer into a framebuffer.
FrameBuffer	convertVP2FB() Convert the viewport into a framebuffer.
void	dumpFB2File(java.lang.String filename) Write the framebuffer to the specified file.
void	dumpPixels2File(int ul_x, int ul_y, int lr_x, int lr_y, java.lang.String filename) Write a rectangular sub array of pixels from the framebuffer to the specified file.
void	dumpVP2File(java.lang.String filename) Write the viewport to the specified file.
void	fbTest() A simple test of the framebuffer.
java.awt.Color	getBgColorFB() Get the background color of the framebuffer.
java.awt.Color	getBgColorVP() Get the background color of the viewport.
int	getHeightFB() Get the height of the framebuffer.
int	getHeightVP() Get the height of the viewport.
java.awt.Point	getLocationVP() Get the upper left hand corner of the viewport.
java.awt.Color	getPixelFB(int x, int y) Get the color of the pixel with coordinates (x,y) in the framebuffer.
java.awt.Color	getPixelVP(int x, int y) Get the color of the pixel with coordinates (x,y) relative to the current viewport.
int	getWidthFB() Get the width of the framebuffer.
int	getWidthVP() Get the width of the viewport.
static void	main(java.lang.String[] args) A main() method for testing the FrameBuffer class.
void	setPixelFB(int x, int y, java.awt.Color c) Set the color of the pixel with coordinates (x,y) in the framebuffer.
void	setPixelVP(int x, int y, java.awt.Color c) Set the color of the pixel with coordinates (x,y) relative to the current viewport.
void	setViewport(int vp_ul_x, int vp_ul_y, FrameBuffer sourceFB) Create a Viewport from a FrameBuffer.
void	setViewport(int vp_ul_x, int vp_ul_y, int width, int height) Set the coordinates, within the FrameBuffer, of the viewport's upper-left-hand corner, width, and height.
void	setViewport(int vp_ul_x, int vp_ul_y, java.lang.String inputFileName) Create a Viewport from a PPM image file.
void	vpTest() A simple test of the viewport.

Methods inherited from class java.lang.Object

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

Field Detail

pixel_buffer

protected int[] pixel_buffer

Constructor Detail

FrameBuffer

public FrameBuffer(int w,
                   int h)

Construct a FrameBuffer with the given dimensions. Initialize the framebuffer to hold all black pixels.

Parameters:

w - Width of the FrameBuffer.

h - Height of the FrameBuffer.

FrameBuffer

public FrameBuffer(java.lang.String inputFileName)

Construct a FrameBuffer from a PPM image file. This can be used to initialize a FrameBuffer with a background image.

Parameters:

inputFileName - Must name a PPM image file with magic number P6.

Method Detail

clearFB

public void clearFB(java.awt.Color c)

Clear the framebuffer (set a background color).

Parameters:

c - color to clear framebuffer with

clearVP

public void clearVP(java.awt.Color c)

Clear the viewport (set a background color).

Parameters:

c - color to clear current viewport with

convertBlue2FB

public FrameBuffer convertBlue2FB()

Convert the blue plane of the framebuffer into a framebuffer.

Returns:

FrameBuffer object holding just blue pixel data from the framebuffer

convertGreen2FB

public FrameBuffer convertGreen2FB()

Convert the green plane of the framebuffer into a framebuffer.

Returns:

FrameBuffer object holding just green pixel data from the framebuffer

convertRed2FB

public FrameBuffer convertRed2FB()

Convert the red plane of the framebuffer into a framebuffer.

Returns:

FrameBuffer object holding just red pixel data from the framebuffer

convertVP2FB

public FrameBuffer convertVP2FB()

Convert the viewport into a framebuffer.

Returns:

FrameBuffer object holding pixel data from the current viewport rectangle

dumpFB2File

public void dumpFB2File(java.lang.String filename)

Write the framebuffer to the specified file.

Parameters:

filename - name of PPM image file to hold framebuffer data

dumpPixels2File

public void dumpPixels2File(int ul_x,
                            int ul_y,
                            int lr_x,
                            int lr_y,
                            java.lang.String filename)

Write a rectangular sub array of pixels from the framebuffer to the specified file.

http://stackoverflow.com/questions/2693631/read-ppm-file-and-store-it-in-an-array-coded-with-c

Parameters:

ul_x - upper left hand x-coordinate of pixel data rectangle

ul_y - upper left hand y-coordinate of pixel data rectangle

lr_x - lower right hand x-coordinate of pixel data rectangle

lr_y - lower right hand y-coordinate of pixel data rectangle

filename - name of PPM image file to hold pixel data

dumpVP2File

public void dumpVP2File(java.lang.String filename)

Write the viewport to the specified file.

Parameters:

filename - name of PPM image file to hold viewport data

fbTest

public void fbTest()

A simple test of the framebuffer. It fills the framebuffer with a test pattern.

getBgColorFB

public java.awt.Color getBgColorFB()

Get the background color of the framebuffer.

Returns:

this framebuffer's background color

getBgColorVP

public java.awt.Color getBgColorVP()

Get the background color of the viewport.

Returns:

background color of current viewport

getHeightFB

public int getHeightFB()

Get the height of the framebuffer.

Returns:

this framebuffer's height

getHeightVP

public int getHeightVP()

Get the height of the viewport.

Returns:

height of the current viewport rectangle

getLocationVP

public java.awt.Point getLocationVP()

Get the upper left hand corner of the viewport.

Returns:

upper left hand corner of current viewport rectangle

getPixelFB

public java.awt.Color getPixelFB(int x,
                                 int y)

Get the color of the pixel with coordinates (x,y) in the framebuffer.

Parameters:

x - horizontal coordinate within the framebuffer

y - vertical coordinate within the framebuffer

Returns:

the color of the current pixel at the given pixel coordinates

getPixelVP

public java.awt.Color getPixelVP(int x,
                                 int y)

Get the color of the pixel with coordinates (x,y) relative to the current viewport.

Parameters:

x - horizontal coordinate within the current viewport

y - vertical coordinate within the current viewport

Returns:

the color of the current pixel at the given viewport coordinates

getWidthFB

public int getWidthFB()

Get the width of the framebuffer.

Returns:

this framebuffer's width

getWidthVP

public int getWidthVP()

Get the width of the viewport.

Returns:

width of the current viewport rectangle

main

public static void main(java.lang.String[] args)

A main() method for testing the FrameBuffer class.

Parameters:

args - command-line arguments to main() method

setPixelFB

public void setPixelFB(int x,
                       int y,
                       java.awt.Color c)

Set the color of the pixel with coordinates (x,y) in the framebuffer.

Parameters:

x - horizontal coordinate within the framebuffer

y - vertical coordinate within the framebuffer

c - color for the pixel at the given pixel coordinates

setPixelVP

public void setPixelVP(int x,
                       int y,
                       java.awt.Color c)

Set the color of the pixel with coordinates (x,y) relative to the current viewport.

Parameters:

x - horizontal coordinate within the current viewport

y - vertical coordinate within the current viewport

c - color for the pixel at the given viewport coordinates

setViewport

public void setViewport(int vp_ul_x,
                        int vp_ul_y,
                        FrameBuffer sourceFB)

Create a Viewport from a FrameBuffer. The size of the viewport will be the size of the source FrameBuffer.

Parameters:

vp_ul_x - upper left hand x-coordinate of new viewport rectangle

vp_ul_y - upper left hand y-coordinate of new viewport rectangle

sourceFB - FrameBuffer to use as the source of the pixel data..

setViewport

public void setViewport(int vp_ul_x,
                        int vp_ul_y,
                        int width,
                        int height)

Set the coordinates, within the FrameBuffer, of the viewport's upper-left-hand corner, width, and height. (Using upper-left-hand corner, width, and height is like Java's Rectangle class and Graphics.drawRect() method.)

Parameters:

vp_ul_x - upper left hand x-coordinate of new viewport rectangle

vp_ul_y - upper left hand y-coordinate of new viewport rectangle

width - viewport's width

height - viewport's height

setViewport

public void setViewport(int vp_ul_x,
                        int vp_ul_y,
                        java.lang.String inputFileName)

Create a Viewport from a PPM image file. The size of the viewport will be the size of the image. This can be used to initialize a Viewport with a background image.

Parameters:

vp_ul_x - upper left hand x-coordinate of new viewport rectangle

vp_ul_y - upper left hand y-coordinate of new viewport rectangle

inputFileName - Must name a PPM image file with magic number P6.

vpTest

public void vpTest()

A simple test of the viewport. It fills the viewport with a test pattern.