Package oracle.spatial.network.nfe.vis.maps.graphics

Class GraphicsUtilities

  • public class GraphicsUtilities
extends java.lang.Object

    GraphicsUtilities contains a set of tools to perform common graphics operations easily. These operations are divided into several themes, listed below.

    Compatible Images

    Compatible images can, and should, be used to increase drawing performance. This class provides a number of methods to load compatible images directly from files or to convert existing images to compatibles images.

    Creating Thumbnails

    This class provides a number of methods to easily scale down images. Some of these methods offer a trade-off between speed and result quality and should be used all the time. They also offer the advantage of producing compatible images, thus automatically resulting into better runtime performance.

    All these methods are both faster than Image.getScaledInstance(int, int, int) and produce better-looking results than the various drawImage() methods in Graphics, which can be used for image scaling.

    Image Manipulation

    This class provides two methods to get and set pixels in a buffered image. These methods try to avoid unmanaging the image in order to keep good performance.

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static java.awt.image.BufferedImage convertToBufferedImage​(java.awt.Image img)
      Converts the specified image into a compatible buffered image.
      static java.awt.image.BufferedImage createColorModelCompatibleImage​(java.awt.image.BufferedImage image)
      Returns a new BufferedImage using the same color model as the image passed as a parameter.
      static java.awt.image.BufferedImage createCompatibleImage​(int width, int height)
      Returns a new opaque compatible image of the specified width and height.
      static java.awt.image.BufferedImage createCompatibleImage​(java.awt.image.BufferedImage image)
      Returns a new compatible image with the same width, height and transparency as the image specified as a parameter.
      static java.awt.image.BufferedImage createCompatibleImage​(java.awt.image.BufferedImage image, int width, int height)
      Returns a new compatible image of the specified width and height, and the same transparency setting as the image specified as a parameter.
      static java.awt.image.BufferedImage createCompatibleTranslucentImage​(int width, int height)
      Returns a new translucent compatible image of the specified width and height.
      static java.awt.image.BufferedImage createThumbnail​(java.awt.image.BufferedImage image, int newSize)
      Returns a thumbnail of a source image.
      static java.awt.image.BufferedImage createThumbnail​(java.awt.image.BufferedImage image, int newWidth, int newHeight)
      Returns a thumbnail of a source image.
      static java.awt.image.BufferedImage createThumbnailFast​(java.awt.image.BufferedImage image, int newSize)
      Returns a thumbnail of a source image.
      static java.awt.image.BufferedImage createThumbnailFast​(java.awt.image.BufferedImage image, int newWidth, int newHeight)
      Returns a thumbnail of a source image.
      static int[] getPixels​(java.awt.image.BufferedImage img, int x, int y, int w, int h, int[] pixels)
      Returns an array of pixels, stored as integers, from a BufferedImage.
      static java.awt.image.BufferedImage loadCompatibleImage​(java.io.InputStream in)
      Returns a new compatible image from a stream.
      static java.awt.image.BufferedImage loadCompatibleImage​(java.net.URL resource)
      Returns a new compatible image from a URL.
      static java.awt.Shape mergeClip​(java.awt.Graphics g, java.awt.Shape clip)
      Sets the clip on a graphics object by merging a supplied clip with the existing one.
      static void setPixels​(java.awt.image.BufferedImage img, int x, int y, int w, int h, int[] pixels)
      Writes a rectangular area of pixels in the destination BufferedImage.
      static java.awt.image.BufferedImage toCompatibleImage​(java.awt.image.BufferedImage image)
      Return a new compatible image that contains a copy of the specified image.

      • Methods inherited from class java.lang.Object

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

    • Method Detail

      • convertToBufferedImage

        public static java.awt.image.BufferedImage convertToBufferedImage​(java.awt.Image img)
        Converts the specified image into a compatible buffered image.
        Parameters:
        img - the image to convert
        Returns:
        a compatible buffered image of the input

      • createColorModelCompatibleImage

        public static java.awt.image.BufferedImage createColorModelCompatibleImage​(java.awt.image.BufferedImage image)

        Returns a new BufferedImage using the same color model as the image passed as a parameter. The returned image is only compatible with the image passed as a parameter. This does not mean the returned image is compatible with the hardware.

        Parameters:
        image - the reference image from which the color model of the new image is obtained
        Returns:
        a new BufferedImage, compatible with the color model of image

      • getPixels

        public static int[] getPixels​(java.awt.image.BufferedImage img,
                              int x,
                              int y,
                              int w,
                              int h,
                              int[] pixels)

        Returns an array of pixels, stored as integers, from a BufferedImage. The pixels are grabbed from a rectangular area defined by a location and two dimensions. Calling this method on an image of type different from BufferedImage.TYPE_INT_ARGB and BufferedImage.TYPE_INT_RGB will unmanage the image.

        Parameters:
        img - the source image
        x - the x location at which to start grabbing pixels
        y - the y location at which to start grabbing pixels
        w - the width of the rectangle of pixels to grab
        h - the height of the rectangle of pixels to grab
        pixels - a pre-allocated array of pixels of size w*h; can be null
        Returns:
        pixels if non-null, a new array of integers otherwise
        Throws:
        java.lang.IllegalArgumentException - is pixels is non-null and of length < w*h

      • setPixels

        public static void setPixels​(java.awt.image.BufferedImage img,
                             int x,
                             int y,
                             int w,
                             int h,
                             int[] pixels)

        Writes a rectangular area of pixels in the destination BufferedImage. Calling this method on an image of type different from BufferedImage.TYPE_INT_ARGB and BufferedImage.TYPE_INT_RGB will unmanage the image.

        Parameters:
        img - the destination image
        x - the x location at which to start storing pixels
        y - the y location at which to start storing pixels
        w - the width of the rectangle of pixels to store
        h - the height of the rectangle of pixels to store
        pixels - an array of pixels, stored as integers
        Throws:
        java.lang.IllegalArgumentException - is pixels is non-null and of length < w*h

      • mergeClip

        public static java.awt.Shape mergeClip​(java.awt.Graphics g,
                                       java.awt.Shape clip)
        Sets the clip on a graphics object by merging a supplied clip with the existing one. The new clip will be an intersection of the old clip and the supplied clip. The old clip shape will be returned. This is useful for resetting the old clip after an operation is performed.
        Parameters:
        g - the graphics object to update
        clip - a new clipping region to add to the graphics clip.
        Returns:
        the current clipping region of the supplied graphics object. This may return null if the current clip is null.
        Throws:
        java.lang.NullPointerException - if any parameter is null