JavaFX 3D - JavaFX 8: A Definitive Guide to Building Desktop, Mobile, and Embedded Java Clients - page 481

Understanding the Image Ops API
The JavaFX Image Ops API allows JavaFX programs to manipulate images at the pixel level. The key to the JavaFX
Image Ops API is a pair of interfaces in the javafx.scene.image package: PixelReader and PixelWriter . You can
obtain a PixelReader from a javafx.scene.image.Image object. And you can obtain a PixelWriter from a
javafx.scene.image.WritableImage object. WritableImage is a subclass of Image .
The PixelReader interface includes the following public methods:

PixelFormat getPixelFormat() •

int getArgb(int x, int y) •

Color getColor(int x, int y) •

<T extends Buffer> void getPixels(int x, int y, int w, int h,
WritablePixelFormat<T> pixelFormat, T buffer, int scanlineStride)

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void getPixels(int x, int y, int w, int h, WritablePixelFormat<ByteBuffer>
pixelFormat, byte[] buffer, int offset, int scanlineStride)

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void getPixels(int x, int y, int w, int h, WritablePixelFormat<IntBuffer>
pixelFormat, int[] buffer, int offset, int scanlineStride)
The getPixelFormat() method returns the pixel format of the underlying image. The getArgb() method returns
the color of the pixel as an 32-bit integer whose 4 bytes from the most significant to the least significant contains the
ARGB components of the color at the specified pixel. The getColor() method returns the color at the specified pixel
as a Color object. The getPixels() methods take the area of the image specified by the first four parameters
( x , y , w , h ), read the color of these pixels, and write them to the buffer according to the WritablePixelFormat , the buffer type,
offset , and scanlineStride .
The PixelWriter interface includes the following public methods:

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PixelFormat getPixelFormat()

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void setArgb(int x, int y, int argb) •

void setColor(int x, int y, Color color) •

<T extends Buffer> void setPixels(int x, int y, int w, int h, PixelFormat<T>
pixelFormat, T buffer, int scanlineStride)

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void setPixels(int x, int y, int w, int h, PixelFormat<ByteBuffer> pixelFormat,
byte[] buffer, int offset, int scanlineStride)

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void setPixels(int x, int y, int w, int h, PixelFormat<IntBuffer> pixelFormat,
int[] buffer, int offset, int scanlineStride)

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void setPixels(int dstx, int dsty, int w, int h, PixelReader reader, int srcx,
int srcy)
The getPixelFormat() method returns the pixel format of the underlying WritableImage . The setArgb()
method sets the color of the pixel ( x , y ) to argb . The setColor() method sets the color of the pixel ( x , y ) to color .
The setPixels() methods that take a pixelFormat parameter set the colors of the pixels in the area ( x , y , w , h ) to
the values specified in buffer , according to the PixelFormat , the buffer type, offset , and scanlineStride . The
setPixels() method that takes a PixelReader sets the colors of the pixels in the area ( dstx , dsty , w , h ) according to
what is available from the PixelReader , starting at the pixel ( srcx , srcy ).
The PixelFormat and WritablePixelFormat describe how the color information of each pixel is stored. Possible
types of PixelFormat are described by the enum PixelFormat.Type , which has the following declarators:
INT_ARGB_PRE , INT_ARGB , BYTE_BGRA_PRE , BYTE_BGRA , BYTE_RGB , BYTE_INDEXED .

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