| /***************************************************************************** |
| * Copyright (C) The Apache Software Foundation. All rights reserved. * |
| * ------------------------------------------------------------------------- * |
| * This software is published under the terms of the Apache Software License * |
| * version 1.1, a copy of which has been included with this distribution in * |
| * the LICENSE file. * |
| *****************************************************************************/ |
| |
| package org.apache.batik.ext.awt; |
| |
| import java.awt.*; |
| import java.awt.color.*; |
| import java.awt.geom.*; |
| import java.awt.image.*; |
| import java.lang.ref.WeakReference; |
| |
| /** This is the superclass for all PaintContexts which use a multiple color |
| * gradient to fill in their raster. It provides the actual color interpolation |
| * functionality. Subclasses only have to deal with using the gradient to fill |
| * pixels in a raster. |
| * |
| * @author Nicholas Talian, Vincent Hardy, Jim Graham, Jerry Evans |
| * @author <a href="mailto:vincent.hardy@eng.sun.com">Vincent Hardy</a> |
| * @version $Id$ |
| * |
| */ |
| abstract class MultipleGradientPaintContext implements PaintContext { |
| |
| /** |
| * PaintContext's ColorModel ARGB if colors are not all opaque. |
| * RGB otherwise. |
| */ |
| protected ColorModel model; |
| |
| /** Color model used if gradient colors are all opaque */ |
| private static ColorModel lrgbmodel_NA = new DirectColorModel |
| (ColorSpace.getInstance(ColorSpace.CS_LINEAR_RGB), |
| 24, 0xff0000, 0xFF00, 0xFF, 0x0, |
| false, DataBuffer.TYPE_INT); |
| |
| private static ColorModel srgbmodel_NA = new DirectColorModel |
| (ColorSpace.getInstance(ColorSpace.CS_sRGB), |
| 24, 0xff0000, 0xFF00, 0xFF, 0x0, |
| false, DataBuffer.TYPE_INT); |
| |
| /** Color model used if some gradient colors are transparent */ |
| private static ColorModel lrgbmodel_A = new DirectColorModel |
| (ColorSpace.getInstance(ColorSpace.CS_LINEAR_RGB), |
| 32, 0xff0000, 0xFF00, 0xFF, 0xFF000000, |
| false, DataBuffer.TYPE_INT); |
| |
| private static ColorModel srgbmodel_A = new DirectColorModel |
| (ColorSpace.getInstance(ColorSpace.CS_sRGB), |
| 32, 0xff0000, 0xFF00, 0xFF, 0xFF000000, |
| false, DataBuffer.TYPE_INT); |
| |
| /** The cached colorModel */ |
| protected static ColorModel cachedModel; |
| |
| /** The cached raster, which is reusable among instances */ |
| protected static WeakReference cached; |
| |
| /** Raster is reused whenever possible */ |
| protected Raster saved; |
| |
| /** The method to use when painting out of the gradient bounds. */ |
| protected MultipleGradientPaint.CycleMethodEnum cycleMethod; |
| |
| /** The colorSpace in which to perform the interpolation */ |
| protected MultipleGradientPaint.ColorSpaceEnum colorSpace; |
| |
| /** Elements of the inverse transform matrix. */ |
| protected float a00, a01, a10, a11, a02, a12; |
| |
| /** This boolean specifies wether we are in simple lookup mode, where an |
| * input value between 0 and 1 may be used to directly index into a single |
| * array of gradient colors. If this boolean value is false, then we have |
| * to use a 2-step process where we have to determine which gradient array |
| * we fall into, then determine the index into that array. |
| */ |
| protected boolean isSimpleLookup = true; |
| |
| /** Size of gradients array for scaling the 0-1 index when looking up |
| * colors the fast way. |
| */ |
| protected int fastGradientArraySize; |
| |
| /** |
| * Array which contains the interpolated color values for each interval, |
| * used by calculateSingleArrayGradient(). It is protected for possible |
| * direct access by subclasses. |
| */ |
| protected int[] gradient; |
| |
| /** Array of gradient arrays, one array for each interval. Used by |
| * calculateMultipleArrayGradient(). |
| */ |
| protected int[][] gradients; |
| |
| /** Length of the 2D slow lookup gradients array. */ |
| protected int gradientsLength; |
| |
| /** Normalized intervals array */ |
| protected float[] normalizedIntervals; |
| |
| /** fractions array */ |
| protected float[] fractions; |
| |
| /** Non-normalized intervals array */ |
| protected float[] intervals; |
| |
| /** Gradient colors */ |
| private Color[] colors; |
| |
| /** Used to determine if gradient colors are all opaque */ |
| private int transparencyTest; |
| |
| /** Colorspace conversion lookup tables */ |
| private static final int SRGBtoLinearRGB[] = new int[256]; |
| private static final int LinearRGBtoSRGB[] = new int[256]; |
| |
| //build the tables |
| static{ |
| for (int k = 0; k < 256; k++) { |
| SRGBtoLinearRGB[k] = convertSRGBtoLinearRGB(k); |
| LinearRGBtoSRGB[k] = convertLinearRGBtoSRGB(k); |
| } |
| } |
| |
| /** Constant number of max colors between any 2 arbitrary colors. |
| * Used for creating and indexing gradients arrays. |
| */ |
| protected static final int GRADIENT_SIZE = 256; |
| protected static final int GRADIENT_SIZE_INDEX = GRADIENT_SIZE -1; |
| |
| /** Maximum length of the fast single-array. If the estimated array size |
| * is greater than this, switch over to the slow lookup method. |
| * No particular reason for choosing this number, but it seems to provide |
| * satisfactory performance for the common case (fast lookup). |
| */ |
| private static final int MAX_GRADIENT_ARRAY_SIZE = 5000; |
| |
| /** Constructor for superclass. Does some initialization, but leaves most |
| * of the heavy-duty math for calculateGradient(), so the subclass may do |
| * some other manipulation beforehand if necessary. This is not possible |
| * if this computation is done in the superclass constructor which always |
| * gets called first. |
| **/ |
| public MultipleGradientPaintContext(ColorModel cm, |
| Rectangle deviceBounds, |
| Rectangle2D userBounds, |
| AffineTransform t, |
| RenderingHints hints, |
| float[] fractions, |
| Color[] colors, |
| MultipleGradientPaint.CycleMethodEnum |
| cycleMethod, |
| MultipleGradientPaint.ColorSpaceEnum |
| colorSpace) |
| throws NoninvertibleTransformException |
| { |
| //We have to deal with the cases where the 1st gradient stop is not |
| //equal to 0 and/or the last gradient stop is not equal to 1. |
| //In both cases, create a new point and replicate the previous |
| //extreme point's color. |
| |
| boolean fixFirst = false; |
| boolean fixLast = false; |
| |
| //if the first gradient stop is not equal to zero, fix this condition |
| if (fractions[0] != 0f) { |
| fixFirst = true; |
| } |
| |
| //if the first gradient stop is not equal to one, fix this condition |
| if (fractions[fractions.length - 1] != 1f) { |
| fixLast = true; |
| } |
| |
| //copy the arrays, leaving room for the new first and last stops |
| if (fixFirst && fixLast) { |
| this.fractions = new float[fractions.length + 2]; |
| System.arraycopy(fractions, 0, this.fractions, |
| 1, fractions.length); |
| this.fractions[0] = 0f; |
| this.fractions[this.fractions.length - 1] = 1f; |
| |
| this.colors = new Color[colors.length + 2]; |
| System.arraycopy(colors, 0, this.colors, |
| 1, colors.length); |
| |
| this.colors[0] = colors[0]; |
| this.colors[this.colors.length - 1] = colors[colors.length - 1]; |
| } |
| //copy the arrays, shifting over to make room for the new first stops |
| else if (fixFirst) { |
| this.fractions = new float[fractions.length + 1]; |
| System.arraycopy(fractions, 0, this.fractions, |
| 1, fractions.length); |
| this.fractions[0] = 0f; |
| |
| this.colors = new Color[colors.length + 1]; |
| System.arraycopy(colors, 0, this.colors, |
| 1, colors.length); |
| this.colors[0] = colors[0]; |
| } |
| //copy the arrays, leaving room for the new last stops |
| else if (fixLast) { |
| this.fractions = new float[fractions.length + 1]; |
| System.arraycopy(fractions, 0, this.fractions, |
| 0, fractions.length); |
| this.fractions[this.fractions.length - 1] = 1f; |
| |
| this.colors = new Color[colors.length + 1]; |
| System.arraycopy(colors, 0, this.colors, |
| 0, colors.length); |
| this.colors[this.colors.length - 1] = colors[colors.length - 1]; |
| } |
| else { //don't fix anything, just copy the arrays. |
| this.fractions = new float[fractions.length]; |
| System.arraycopy(fractions, 0, this.fractions, |
| 0, fractions.length); |
| |
| this.colors = new Color[colors.length]; |
| System.arraycopy(colors, 0, this.colors, |
| 0, colors.length); |
| } |
| |
| //this will store the intervals (distances) between gradient stops |
| intervals = new float[this.fractions.length - 1]; |
| |
| float currentPosition = this.fractions[0]; |
| float previousPosition = 0; |
| |
| //convert from fractions into intervals, check that values are in |
| //the proper range and progress in increasing order from 0 to 1 |
| for (int i = 1; i < this.fractions.length; i++) { |
| |
| if (currentPosition < 0f || currentPosition > 1f) { |
| throw new IllegalArgumentException("Keyframe values should " + |
| "be in the range 0 to 1: " + |
| currentPosition); |
| } |
| |
| previousPosition = currentPosition; |
| currentPosition = this.fractions[i]; |
| |
| if (currentPosition < previousPosition) { |
| throw |
| new IllegalArgumentException("Keyframe fractions must be" + |
| " increasing: " + |
| currentPosition); |
| } |
| |
| //interval distance is equal to the difference in positions |
| intervals[i-1] = currentPosition - previousPosition; |
| } |
| |
| //copy the non-normalized intervals array |
| normalizedIntervals = new float[intervals.length]; |
| System.arraycopy(intervals, 0, |
| normalizedIntervals, 0, |
| intervals.length); |
| |
| // Normalize intervals and check values are positive. |
| float sum = 0; |
| |
| for(int i = 0; i < intervals.length; i++) { |
| sum += intervals[i]; |
| } |
| |
| for(int i = 0; i < normalizedIntervals.length; i++) { |
| normalizedIntervals[i] /= sum; |
| } |
| |
| // The inverse transform is needed to from device to user space. |
| // Get all the components of the inverse transform matrix. |
| AffineTransform tInv = t.createInverse(); |
| double m[] = new double[6]; |
| tInv.getMatrix(m); |
| a00 = (float)m[0]; |
| a10 = (float)m[1]; |
| a01 = (float)m[2]; |
| a11 = (float)m[3]; |
| a02 = (float)m[4]; |
| a12 = (float)m[5]; |
| |
| //copy some flags |
| this.cycleMethod = cycleMethod; |
| this.colorSpace = colorSpace; |
| |
| |
| // Setup an example Model, we may refine it later. |
| if (cm.getColorSpace() == lrgbmodel_A.getColorSpace()) |
| model = lrgbmodel_A; |
| else if (cm.getColorSpace() == srgbmodel_A.getColorSpace()) |
| model = srgbmodel_A; |
| else |
| throw new IllegalArgumentException |
| ("Unsupported ColorSpace for interpolation"); |
| } |
| |
| |
| /** This function is the meat of this class. It calculates an array of |
| * gradient colors based on an array of fractions and color values at those |
| * fractions. |
| */ |
| protected final void calculateGradientFractions() { |
| |
| //if interpolation should occur in Linear RGB space, convert the |
| //colors using the lookup table |
| if (colorSpace == LinearGradientPaint.LINEAR_RGB) { |
| for (int i = 0; i < colors.length; i++) { |
| colors[i] = new Color(SRGBtoLinearRGB[colors[i].getRed()], |
| SRGBtoLinearRGB[colors[i].getGreen()], |
| SRGBtoLinearRGB[colors[i].getBlue()]); |
| } |
| } |
| |
| //initialize to be fully opaque for ANDing with colors |
| transparencyTest = 0xff000000; |
| |
| //array of interpolation arrays |
| gradients = new int[fractions.length - 1][]; |
| gradientsLength = gradients.length; |
| |
| // Find smallest interval |
| int n = normalizedIntervals.length; |
| |
| float Imin = 1; |
| |
| for(int i = 0; i < n; i++) { |
| Imin = (Imin > normalizedIntervals[i]) ? |
| normalizedIntervals[i] : Imin; |
| } |
| |
| //estimate the size of the entire gradients array. |
| //This is to prevent a tiny interval from causing the size of array to |
| //explode. If the estimated size is too large, break to using |
| //seperate arrays for each interval, and using an indexing scheme at |
| //look-up time. |
| int estimatedSize = 0; |
| |
| if (Imin == 0) { |
| estimatedSize = Integer.MAX_VALUE; |
| } else { |
| for (int i = 0; i < normalizedIntervals.length; i++) { |
| estimatedSize += (normalizedIntervals[i]/Imin) * GRADIENT_SIZE; |
| } |
| } |
| |
| if (estimatedSize > MAX_GRADIENT_ARRAY_SIZE) { |
| //slow method |
| calculateMultipleArrayGradient(); |
| } else { |
| //fast method |
| calculateSingleArrayGradient(Imin); |
| } |
| |
| // Use the most 'economical' model. |
| if((transparencyTest >>> 24) == 0xff) { |
| if (model.getColorSpace() == lrgbmodel_NA.getColorSpace()) |
| model = lrgbmodel_NA; |
| else if (model.getColorSpace() == srgbmodel_NA.getColorSpace()) |
| model = srgbmodel_NA; |
| } |
| } |
| |
| |
| /** |
| * FAST LOOKUP METHOD |
| * |
| * This method calculates the gradient color values and places them in a |
| * single int array, gradient[]. It does this by allocating space for |
| * each interval based on its size relative to the smallest interval in |
| * the array. The smallest interval is allocated 255 interpolated values |
| * (the maximum number of unique in-between colors in a 24 bit color |
| * system), and all other intervals are allocated |
| * size = (255 * the ratio of their size to the smallest interval). |
| * |
| * This scheme expedites a speedy retrieval because the colors are |
| * distributed along the array according to their user-specified |
| * distribution. All that is needed is a relative index from 0 to 1. |
| * |
| * The only problem with this method is that the possibility exists for |
| * the array size to balloon in the case where there is a |
| * disproportionately small gradient interval. In this case the other |
| * intervals will be allocated huge space, but much of that data is |
| * redundant. We thus need to use the space conserving scheme below. |
| * |
| * @param Imin the size of the smallest interval |
| * |
| */ |
| private void calculateSingleArrayGradient(float Imin) { |
| |
| //set the flag so we know later it is a non-simple lookup |
| isSimpleLookup = true; |
| |
| int rgb1; //2 colors to interpolate |
| int rgb2; |
| |
| int gradientsTot = 1; //the eventual size of the single array |
| |
| //for every interval (transition between 2 colors) |
| for(int i=0; i < gradients.length; i++){ |
| |
| //create an array whose size is based on the ratio to the |
| //smallest interval. |
| int nGradients = (int)((normalizedIntervals[i]/Imin)*255f); |
| gradientsTot += nGradients; |
| gradients[i] = new int[nGradients]; |
| |
| //the the 2 colors (keyframes) to interpolate between |
| rgb1 = colors[i].getRGB(); |
| rgb2 = colors[i+1].getRGB(); |
| |
| //fill this array with the colors in between rgb1 and rgb2 |
| interpolate(rgb1, rgb2, gradients[i]); |
| |
| //if the colors are opaque, transparency should still be 0xff000000 |
| transparencyTest &= rgb1; |
| transparencyTest &= rgb2; |
| } |
| |
| // Put all gradients in a single array |
| gradient = new int[gradientsTot]; |
| int curOffset = 0; |
| for(int i = 0; i < gradients.length; i++){ |
| System.arraycopy(gradients[i], 0, gradient, |
| curOffset, gradients[i].length); |
| curOffset += gradients[i].length; |
| } |
| gradient[gradient.length-1] = colors[colors.length-1].getRGB(); |
| |
| //if interpolation occurred in Linear RGB space, convert the |
| //gradients back to SRGB using the lookup table |
| if (colorSpace == LinearGradientPaint.LINEAR_RGB) { |
| if (model.getColorSpace() == |
| ColorSpace.getInstance(ColorSpace.CS_sRGB)) { |
| for (int i = 0; i < gradient.length; i++) { |
| gradient[i] = |
| convertEntireColorLinearRGBtoSRGB(gradient[i]); |
| } |
| } |
| } else { |
| if (model.getColorSpace() == |
| ColorSpace.getInstance(ColorSpace.CS_LINEAR_RGB)) { |
| for (int i = 0; i < gradient.length; i++) { |
| gradient[i] = |
| convertEntireColorSRGBtoLinearRGB(gradient[i]); |
| } |
| } |
| } |
| |
| fastGradientArraySize = gradient.length - 1; |
| } |
| |
| |
| /** |
| * SLOW LOOKUP METHOD |
| * |
| * This method calculates the gradient color values for each interval and |
| * places each into its own 255 size array. The arrays are stored in |
| * gradients[][]. (255 is used because this is the maximum number of |
| * unique colors between 2 arbitrary colors in a 24 bit color system) |
| * |
| * This method uses the minimum amount of space (only 255 * number of |
| * intervals), but it aggravates the lookup procedure, because now we |
| * have to find out which interval to select, then calculate the index |
| * within that interval. This causes a significant performance hit, |
| * because it requires this calculation be done for every point in |
| * the rendering loop. |
| * |
| * For those of you who are interested, this is a classic example of the |
| * time-space tradeoff. |
| * |
| */ |
| private void calculateMultipleArrayGradient() { |
| |
| //set the flag so we know later it is a non-simple lookup |
| isSimpleLookup = false; |
| |
| int rgb1; //2 colors to interpolate |
| int rgb2; |
| |
| //for every interval (transition between 2 colors) |
| for(int i=0; i < gradients.length; i++){ |
| |
| //create an array of the maximum theoretical size for each interval |
| gradients[i] = new int[GRADIENT_SIZE]; |
| |
| //get the the 2 colors |
| rgb1 = colors[i].getRGB(); |
| rgb2 = colors[i+1].getRGB(); |
| |
| //fill this array with the colors in between rgb1 and rgb2 |
| interpolate(rgb1, rgb2, gradients[i]); |
| |
| //if the colors are opaque, transparency should still be 0xff000000 |
| transparencyTest &= rgb1; |
| transparencyTest &= rgb2; |
| } |
| |
| //if interpolation occurred in Linear RGB space, convert the |
| //gradients back to SRGB using the lookup table |
| if (colorSpace == LinearGradientPaint.LINEAR_RGB) { |
| if (model.getColorSpace() == |
| ColorSpace.getInstance(ColorSpace.CS_sRGB)) { |
| for (int j = 0; j < gradients.length; j++) { |
| for (int i = 0; i < gradients[j].length; i++) { |
| gradients[j][i] = |
| convertEntireColorLinearRGBtoSRGB(gradients[j][i]); |
| } |
| } |
| } |
| } else { |
| if (model.getColorSpace() == |
| ColorSpace.getInstance(ColorSpace.CS_LINEAR_RGB)) { |
| for (int j = 0; j < gradients.length; j++) { |
| for (int i = 0; i < gradients[j].length; i++) { |
| gradients[j][i] = |
| convertEntireColorSRGBtoLinearRGB(gradients[j][i]); |
| } |
| } |
| } |
| } |
| } |
| |
| /** Yet another helper function. This one linearly interpolates between |
| * 2 colors, filling up the output array. |
| * |
| * @param rgb1 the start color |
| * @param rgb2 the end color |
| * @param output the output array of colors... assuming this is not null. |
| * |
| */ |
| private void interpolate(int rgb1, int rgb2, int[] output) { |
| |
| int a1, r1, g1, b1, da, dr, dg, db; //color components |
| |
| //step between interpolated values. |
| float stepSize = 1/(float)output.length; |
| |
| //extract color components from packed integer |
| a1 = (rgb1 >> 24) & 0xff; |
| r1 = (rgb1 >> 16) & 0xff; |
| g1 = (rgb1 >> 8) & 0xff; |
| b1 = (rgb1 ) & 0xff; |
| //calculate the total change in alpha, red, green, blue |
| da = ((rgb2 >> 24) & 0xff) - a1; |
| dr = ((rgb2 >> 16) & 0xff) - r1; |
| dg = ((rgb2 >> 8) & 0xff) - g1; |
| db = ((rgb2 ) & 0xff) - b1; |
| |
| //for each step in the interval calculate the in-between color by |
| //multiplying the normalized current position by the total color change |
| //(.5 is added to prevent truncation round-off error) |
| for (int i = 0; i < output.length; i++) { |
| output[i] = |
| (((int) ((a1 + i * da * stepSize) + .5) << 24)) | |
| (((int) ((r1 + i * dr * stepSize) + .5) << 16)) | |
| (((int) ((g1 + i * dg * stepSize) + .5) << 8)) | |
| (((int) ((b1 + i * db * stepSize) + .5) )); |
| } |
| } |
| |
| |
| /** Yet another helper function. This one extracts the color components |
| * of an integer RGB triple, converts them from LinearRGB to SRGB, then |
| * recompacts them into an int. |
| */ |
| private int convertEntireColorLinearRGBtoSRGB(int rgb) { |
| |
| int a1, r1, g1, b1; //color components |
| |
| //extract red, green, blue components |
| a1 = (rgb >> 24) & 0xff; |
| r1 = (rgb >> 16) & 0xff; |
| g1 = (rgb >> 8) & 0xff; |
| b1 = rgb & 0xff; |
| |
| //use the lookup table |
| r1 = LinearRGBtoSRGB[r1]; |
| g1 = LinearRGBtoSRGB[g1]; |
| b1 = LinearRGBtoSRGB[b1]; |
| |
| //re-compact the components |
| return ((a1 << 24) | |
| (r1 << 16) | |
| (g1 << 8) | |
| b1); |
| } |
| |
| /** Yet another helper function. This one extracts the color components |
| * of an integer RGB triple, converts them from LinearRGB to SRGB, then |
| * recompacts them into an int. |
| */ |
| private int convertEntireColorSRGBtoLinearRGB(int rgb) { |
| |
| int a1, r1, g1, b1; //color components |
| |
| //extract red, green, blue components |
| a1 = (rgb >> 24) & 0xff; |
| r1 = (rgb >> 16) & 0xff; |
| g1 = (rgb >> 8) & 0xff; |
| b1 = rgb & 0xff; |
| |
| //use the lookup table |
| r1 = SRGBtoLinearRGB[r1]; |
| g1 = SRGBtoLinearRGB[g1]; |
| b1 = SRGBtoLinearRGB[b1]; |
| |
| //re-compact the components |
| return ((a1 << 24) | |
| (r1 << 16) | |
| (g1 << 8) | |
| b1); |
| } |
| |
| |
| /** Helper function to index into the gradients array. This is necessary |
| * because each interval has an array of colors with uniform size 255. |
| * However, the color intervals are not necessarily of uniform length, so |
| * a conversion is required. |
| * |
| * @param position the unmanipulated position. want to map this into the |
| * range 0 to 1 |
| * |
| * @returns integer color to display |
| * |
| */ |
| protected final int indexIntoGradientsArrays(float position) { |
| |
| //first, manipulate position value depending on the cycle method. |
| |
| if (cycleMethod == MultipleGradientPaint.NO_CYCLE) { |
| |
| if (position > 1) { //upper bound is 1 |
| position = 1; |
| } |
| |
| else if (position < 0) { //lower bound is 0 |
| position = 0; |
| } |
| } |
| |
| else if (cycleMethod == MultipleGradientPaint.REPEAT) { |
| //get the fractional part |
| //(modulo behavior discards integer component) |
| position = position - (int)position; |
| |
| //position should now be between -1 and 1 |
| |
| if (position < 0) { |
| position = position + 1; //force it to be in the range 0-1 |
| } |
| } |
| |
| else { //cycleMethod == MultipleGradientPaint.REFLECT |
| |
| if (position < 0) { |
| position = -position; //take absolute value |
| } |
| |
| int part = (int)position; //take the integer part |
| |
| position = position - part; //get the fractional part |
| |
| if ((part & 0x00000001) == 1) { //if integer part is odd |
| position = 1 - position; //want the reflected color instead |
| } |
| } |
| |
| //now, get the color based on this 0-1 position: |
| |
| if (isSimpleLookup) { //easy to compute: just scale index by array size |
| return gradient[(int)(position * fastGradientArraySize)]; |
| } |
| |
| else { //more complicated computation, to save space |
| |
| //for all the gradient interval arrays |
| for (int i = 0; i < gradientsLength; i++) { |
| |
| if (position < fractions[i+1]) { //this is the array we want |
| |
| float delta = position - fractions[i]; |
| |
| //this is the interval we want. |
| int index = (int)((delta / normalizedIntervals[i]) |
| * (GRADIENT_SIZE_INDEX)); |
| |
| return gradients[i][index]; |
| } |
| } |
| |
| } |
| |
| return gradients[gradients.length - 1][GRADIENT_SIZE_INDEX]; |
| } |
| |
| /** Helper function to convert a color component in sRGB space to linear |
| * RGB space. Used to build a static lookup table. |
| */ |
| private static int convertSRGBtoLinearRGB(int color) { |
| |
| float input, output; |
| |
| input = ((float) color) / 255.0f; |
| if (input <= 0.04045f) { |
| output = input / 12.92f; |
| } |
| else { |
| output = (float) Math.pow((input + 0.055) / 1.055, 2.4); |
| } |
| int o = Math.round(output * 255.0f); |
| |
| return o; |
| } |
| |
| /** Helper function to convert a color component in linear RGB space to |
| * SRGB space. Used to build a static lookup table. |
| */ |
| private static int convertLinearRGBtoSRGB(int color) { |
| |
| float input, output; |
| |
| input = ((float) color) / 255.0f; |
| |
| if (input <= 0.0031308) { |
| output = input * 12.92f; |
| } |
| else { |
| output = (1.055f * |
| ((float) Math.pow(input, (1.0 / 2.4)))) - 0.055f; |
| } |
| |
| int o = Math.round(output * 255.0f); |
| |
| return o; |
| } |
| |
| |
| /** Superclass getRaster... */ |
| public final Raster getRaster(int x, int y, int w, int h) { |
| // |
| // If working raster is big enough, reuse it. Otherwise, |
| // build a large enough new one. |
| // |
| Raster raster = saved; |
| if (raster == null || raster.getWidth() < w || raster.getHeight() < h) |
| { |
| raster = getCachedRaster(model, w, h); |
| saved = raster; |
| } |
| // |
| // Access raster internal int array. Because we use a DirectColorModel, |
| // we know the DataBuffer is of type DataBufferInt and the SampleModel |
| // is SinglePixelPackedSampleModel. |
| // Adjust for initial offset in DataBuffer and also for the scanline |
| // stride. |
| // |
| DataBufferInt rasterDB = (DataBufferInt)raster.getDataBuffer(); |
| int[] pixels = rasterDB.getBankData()[0]; |
| int off = rasterDB.getOffset(); |
| int scanlineStride = ((SinglePixelPackedSampleModel) |
| raster.getSampleModel()).getScanlineStride(); |
| int adjust = scanlineStride - w; |
| |
| fillRaster(pixels, off, adjust, x, y, w, h); //delegate to subclass. |
| |
| return raster; |
| } |
| |
| /** Subclasses should implement this. */ |
| protected abstract void fillRaster(int pixels[], int off, int adjust, |
| int x, int y, int w, int h); |
| |
| |
| /** Took this cacheRaster code from GradientPaint. It appears to recycle |
| * rasters for use by any other instance, as long as they are sufficiently |
| * large. |
| */ |
| protected final |
| static synchronized Raster getCachedRaster(ColorModel cm, int w, int h) { |
| if (cm == cachedModel) { |
| if (cached != null) { |
| Raster ras = (Raster) cached.get(); |
| if (ras != null && |
| ras.getWidth() >= w && |
| ras.getHeight() >= h) |
| { |
| cached = null; |
| return ras; |
| } |
| } |
| } |
| return cm.createCompatibleWritableRaster(w, h); |
| } |
| |
| /** Took this cacheRaster code from GradientPaint. It appears to recycle |
| * rasters for use by any other instance, as long as they are sufficiently |
| * large. |
| */ |
| protected final |
| static synchronized void putCachedRaster(ColorModel cm, Raster ras) { |
| if (cached != null) { |
| Raster cras = (Raster) cached.get(); |
| if (cras != null) { |
| int cw = cras.getWidth(); |
| int ch = cras.getHeight(); |
| int iw = ras.getWidth(); |
| int ih = ras.getHeight(); |
| if (cw >= iw && ch >= ih) { |
| return; |
| } |
| if (cw * ch >= iw * ih) { |
| return; |
| } |
| } |
| } |
| cachedModel = cm; |
| cached = new WeakReference(ras); |
| } |
| |
| /** |
| * Release the resources allocated for the operation. |
| */ |
| public final void dispose() { |
| if (saved != null) { |
| putCachedRaster(model, saved); |
| saved = null; |
| } |
| } |
| |
| /** |
| * Return the ColorModel of the output. |
| */ |
| public final ColorModel getColorModel() { |
| return model; |
| } |
| } |
| |
