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Diffstat (limited to 'libjava/classpath/java/awt/image/MultiPixelPackedSampleModel.java')
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1 files changed, 603 insertions, 0 deletions
diff --git a/libjava/classpath/java/awt/image/MultiPixelPackedSampleModel.java b/libjava/classpath/java/awt/image/MultiPixelPackedSampleModel.java new file mode 100644 index 000000000..592611cbb --- /dev/null +++ b/libjava/classpath/java/awt/image/MultiPixelPackedSampleModel.java @@ -0,0 +1,603 @@ +/* Copyright (C) 2004, 2006, Free Software Foundation + +This file is part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301 USA. + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + +package java.awt.image; + +import gnu.java.awt.Buffers; +import gnu.java.lang.CPStringBuilder; + +/** + * MultiPixelPackedSampleModel provides a single band model that supports + * multiple pixels in a single unit. Pixels have 2^n bits and 2^k pixels fit + * per data element. + * + * @author Jerry Quinn (jlquinn@optonline.net) + */ +public class MultiPixelPackedSampleModel extends SampleModel +{ + private int scanlineStride; + private int[] bitMasks; + private int[] bitOffsets; + private int[] sampleSize; + private int dataBitOffset; + private int elemBits; + private int numberOfBits; + private int numElems; + + /** + * Creates a new <code>MultiPixelPackedSampleModel</code> with the specified + * data type, which should be one of: + * <ul> + * <li>{@link DataBuffer#TYPE_BYTE};</li> + * <li>{@link DataBuffer#TYPE_USHORT};</li> + * <li>{@link DataBuffer#TYPE_INT};</li> + * </ul> + * + * @param dataType the data type. + * @param w the width (in pixels). + * @param h the height (in pixels). + * @param numberOfBits the number of bits per pixel (must be a power of 2). + */ + public MultiPixelPackedSampleModel(int dataType, int w, int h, + int numberOfBits) + { + this(dataType, w, h, numberOfBits, 0, 0); + } + + /** + * Creates a new <code>MultiPixelPackedSampleModel</code> with the specified + * data type, which should be one of: + * <ul> + * <li>{@link DataBuffer#TYPE_BYTE};</li> + * <li>{@link DataBuffer#TYPE_USHORT};</li> + * <li>{@link DataBuffer#TYPE_INT};</li> + * </ul> + * + * @param dataType the data type. + * @param w the width (in pixels). + * @param h the height (in pixels). + * @param numberOfBits the number of bits per pixel (must be a power of 2). + * @param scanlineStride the number of data elements from a pixel on one + * row to the corresponding pixel in the next row. + * @param dataBitOffset the offset to the first data bit. + */ + public MultiPixelPackedSampleModel(int dataType, int w, int h, + int numberOfBits, int scanlineStride, + int dataBitOffset) + { + super(dataType, w, h, 1); + + switch (dataType) + { + case DataBuffer.TYPE_BYTE: + elemBits = 8; + break; + case DataBuffer.TYPE_USHORT: + elemBits = 16; + break; + case DataBuffer.TYPE_INT: + elemBits = 32; + break; + default: + throw new IllegalArgumentException("MultiPixelPackedSampleModel" + + " unsupported dataType"); + } + + this.dataBitOffset = dataBitOffset; + + this.numberOfBits = numberOfBits; + if (numberOfBits > elemBits) + throw new RasterFormatException("MultiPixelPackedSampleModel pixel size" + + " larger than dataType"); + switch (numberOfBits) + { + case 1: case 2: case 4: case 8: case 16: case 32: break; + default: + throw new RasterFormatException("MultiPixelPackedSampleModel pixel" + + " size not 2^n bits"); + } + numElems = elemBits / numberOfBits; + + // Compute scan line large enough for w pixels. + if (scanlineStride == 0) + scanlineStride = ((dataBitOffset + w * numberOfBits) - 1) / elemBits + 1; + this.scanlineStride = scanlineStride; + + + sampleSize = new int[1]; + sampleSize[0] = numberOfBits; + + bitMasks = new int[numElems]; + bitOffsets = new int[numElems]; + for (int i=0; i < numElems; i++) + { + bitOffsets[numElems - i- 1] = numberOfBits * i; + bitMasks[numElems - i - 1] = ((1 << numberOfBits) - 1) << + bitOffsets[numElems - i - 1]; + } + } + + /** + * Creates a new <code>MultiPixelPackedSample</code> model with the same + * data type and bits per pixel as this model, but with the specified + * dimensions. + * + * @param w the width (in pixels). + * @param h the height (in pixels). + * + * @return The new sample model. + */ + public SampleModel createCompatibleSampleModel(int w, int h) + { + /* FIXME: We can avoid recalculation of bit offsets and sample + sizes here by passing these from the current instance to a + special private constructor. */ + return new MultiPixelPackedSampleModel(dataType, w, h, numberOfBits); + } + + /** + * Creates a DataBuffer for holding pixel data in the format and + * layout described by this SampleModel. The returned buffer will + * consist of one single bank. + * + * @return A new data buffer. + */ + public DataBuffer createDataBuffer() + { + int size = scanlineStride * height; + if (dataBitOffset > 0) + size += (dataBitOffset - 1) / elemBits + 1; + return Buffers.createBuffer(getDataType(), size); + } + + /** + * Returns the number of data elements required to transfer a pixel in the + * get/setDataElements() methods. + * + * @return <code>1</code>. + */ + public int getNumDataElements() + { + return 1; + } + + /** + * Returns an array containing the size (in bits) of the samples in each + * band. The <code>MultiPixelPackedSampleModel</code> class supports only + * one band, so this method returns an array with length <code>1</code>. + * + * @return An array containing the size (in bits) of the samples in band zero. + * + * @see #getSampleSize(int) + */ + public int[] getSampleSize() + { + return (int[]) sampleSize.clone(); + } + + /** + * Returns the size of the samples in the specified band. Note that the + * <code>MultiPixelPackedSampleModel</code> supports only one band -- this + * method ignored the <code>band</code> argument, and always returns the size + * of band zero. + * + * @param band the band (this parameter is ignored). + * + * @return The size of the samples in band zero. + * + * @see #getSampleSize() + */ + public int getSampleSize(int band) + { + return sampleSize[0]; + } + + /** + * Returns the index in the data buffer that stores the pixel at (x, y). + * + * @param x the x-coordinate. + * @param y the y-coordinate. + * + * @return The index in the data buffer that stores the pixel at (x, y). + * + * @see #getBitOffset(int) + */ + public int getOffset(int x, int y) + { + return scanlineStride * y + ((dataBitOffset + x * numberOfBits) / elemBits); + } + + /** + * The bit offset (within an element in the data buffer) of the pixels with + * the specified x-coordinate. + * + * @param x the x-coordinate. + * + * @return The bit offset. + */ + public int getBitOffset(int x) + { + return (dataBitOffset + x * numberOfBits) % elemBits; + } + + /** + * Returns the offset to the first data bit. + * + * @return The offset to the first data bit. + */ + public int getDataBitOffset() + { + return dataBitOffset; + } + + /** + * Returns the number of data elements from a pixel in one row to the + * corresponding pixel in the next row. + * + * @return The scanline stride. + */ + public int getScanlineStride() + { + return scanlineStride; + } + + /** + * Returns the number of bits per pixel. + * + * @return The number of bits per pixel. + */ + public int getPixelBitStride() + { + return numberOfBits; + } + + /** + * Returns the transfer type, which is one of the following (depending on + * the number of bits per sample for this model): + * <ul> + * <li>{@link DataBuffer#TYPE_BYTE};</li> + * <li>{@link DataBuffer#TYPE_USHORT};</li> + * <li>{@link DataBuffer#TYPE_INT};</li> + * </ul> + * + * @return The transfer type. + */ + public int getTransferType() + { + if (numberOfBits <= DataBuffer.getDataTypeSize(DataBuffer.TYPE_BYTE)) + return DataBuffer.TYPE_BYTE; + else if (numberOfBits <= DataBuffer.getDataTypeSize(DataBuffer.TYPE_USHORT)) + return DataBuffer.TYPE_USHORT; + return DataBuffer.TYPE_INT; + } + + /** + * Normally this method returns a sample model for accessing a subset of + * bands of image data, but since <code>MultiPixelPackedSampleModel</code> + * only supports a single band, this overridden implementation just returns + * a new instance of <code>MultiPixelPackedSampleModel</code>, with the same + * attributes as this instance. + * + * @param bands the bands to include in the subset (this is ignored, except + * that if it is non-<code>null</code> a check is made to ensure that the + * array length is equal to <code>1</code>). + * + * @throws RasterFormatException if <code>bands</code> is not + * <code>null</code> and <code>bands.length != 1</code>. + */ + public SampleModel createSubsetSampleModel(int[] bands) + { + if (bands != null && bands.length != 1) + throw new RasterFormatException("MultiPixelPackedSampleModel only" + + " supports one band"); + return new MultiPixelPackedSampleModel(dataType, width, height, + numberOfBits, scanlineStride, dataBitOffset); + } + + /** + * Extract one pixel and return in an array of transfer type. + * + * Extracts the pixel at x, y from data and stores into the 0th index of the + * array obj, since there is only one band. If obj is null, a new array of + * getTransferType() is created. + * + * @param x The x-coordinate of the pixel rectangle to store in + * <code>obj</code>. + * @param y The y-coordinate of the pixel rectangle to store in + * <code>obj</code>. + * @param obj The primitive array to store the pixels into or null to force + * creation. + * @param data The DataBuffer that is the source of the pixel data. + * @return The primitive array containing the pixel data. + * @see java.awt.image.SampleModel#getDataElements(int, int, Object, + * DataBuffer) + */ + public Object getDataElements(int x, int y, Object obj, DataBuffer data) + { + int pixel = getSample(x, y, 0, data); + switch (getTransferType()) + { + case DataBuffer.TYPE_BYTE: + if (obj == null) + obj = new byte[1]; + ((byte[]) obj)[0] = (byte) pixel; + return obj; + case DataBuffer.TYPE_USHORT: + if (obj == null) + obj = new short[1]; + ((short[]) obj)[0] = (short) pixel; + return obj; + case DataBuffer.TYPE_INT: + if (obj == null) + obj = new int[1]; + ((int[]) obj)[0] = pixel; + return obj; + default: + // Seems like the only sensible thing to do. + throw new ClassCastException(); + } + } + + /** + * Returns an array (of length 1) containing the sample for the pixel at + * (x, y) in the specified data buffer. If <code>iArray</code> is not + * <code>null</code>, it will be populated with the sample value and + * returned as the result of this function (this avoids allocating a new + * array instance). + * + * @param x the x-coordinate of the pixel. + * @param y the y-coordinate of the pixel. + * @param iArray an array to populate with the sample values and return as + * the result (if <code>null</code>, a new array will be allocated). + * @param data the data buffer (<code>null</code> not permitted). + * + * @return An array containing the pixel sample value. + * + * @throws NullPointerException if <code>data</code> is <code>null</code>. + */ + public int[] getPixel(int x, int y, int[] iArray, DataBuffer data) + { + if (iArray == null) + iArray = new int[1]; + iArray[0] = getSample(x, y, 0, data); + return iArray; + } + + /** + * Returns the sample value for the pixel at (x, y) in the specified data + * buffer. + * + * @param x the x-coordinate of the pixel. + * @param y the y-coordinate of the pixel. + * @param b the band (in the range <code>0</code> to + * <code>getNumBands() - 1</code>). + * @param data the data buffer (<code>null</code> not permitted). + * + * @return The sample value. + * + * @throws NullPointerException if <code>data</code> is <code>null</code>. + */ + public int getSample(int x, int y, int b, DataBuffer data) + { + int pos = + ((dataBitOffset + x * numberOfBits) % elemBits) / numberOfBits; + int offset = getOffset(x, y); + int samples = data.getElem(offset); + return (samples & bitMasks[pos]) >>> bitOffsets[pos]; + } + + /** + * Set the pixel at x, y to the value in the first element of the primitive + * array obj. + * + * @param x The x-coordinate of the data elements in <code>obj</code>. + * @param y The y-coordinate of the data elements in <code>obj</code>. + * @param obj The primitive array containing the data elements to set. + * @param data The DataBuffer to store the data elements into. + */ + public void setDataElements(int x, int y, Object obj, DataBuffer data) + { + int transferType = getTransferType(); + try + { + switch (transferType) + { + case DataBuffer.TYPE_BYTE: + { + byte[] in = (byte[]) obj; + setSample(x, y, 0, in[0] & 0xFF, data); + return; + } + case DataBuffer.TYPE_USHORT: + { + short[] in = (short[]) obj; + setSample(x, y, 0, in[0] & 0xFFFF, data); + return; + } + case DataBuffer.TYPE_INT: + { + int[] in = (int[]) obj; + setSample(x, y, 0, in[0], data); + return; + } + default: + throw new ClassCastException("Unsupported data type"); + } + } + catch (ArrayIndexOutOfBoundsException aioobe) + { + String msg = "While writing data elements" + + ", x=" + x + ", y=" + y + + ", width=" + width + ", height=" + height + + ", scanlineStride=" + scanlineStride + + ", offset=" + getOffset(x, y) + + ", data.getSize()=" + data.getSize() + + ", data.getOffset()=" + data.getOffset() + + ": " + aioobe; + throw new ArrayIndexOutOfBoundsException(msg); + } + } + + /** + * Sets the sample value for the pixel at (x, y) in the specified data + * buffer to the specified value. + * + * @param x the x-coordinate of the pixel. + * @param y the y-coordinate of the pixel. + * @param iArray the sample value (<code>null</code> not permitted). + * @param data the data buffer (<code>null</code> not permitted). + * + * @throws NullPointerException if either <code>iArray</code> or + * <code>data</code> is <code>null</code>. + * + * @see #setSample(int, int, int, int, DataBuffer) + */ + public void setPixel(int x, int y, int[] iArray, DataBuffer data) + { + setSample(x, y, 0, iArray[0], data); + } + + /** + * Sets the sample value for a band for the pixel at (x, y) in the + * specified data buffer. + * + * @param x the x-coordinate of the pixel. + * @param y the y-coordinate of the pixel. + * @param b the band (in the range <code>0</code> to + * <code>getNumBands() - 1</code>). + * @param s the sample value. + * @param data the data buffer (<code>null</code> not permitted). + * + * @throws NullPointerException if <code>data</code> is <code>null</code>. + */ + public void setSample(int x, int y, int b, int s, DataBuffer data) + { + int bitpos = + ((dataBitOffset + x * numberOfBits) % elemBits) / numberOfBits; + int offset = getOffset(x, y); + + s = s << bitOffsets[bitpos]; + s = s & bitMasks[bitpos]; + + int sample = data.getElem(offset); + sample |= s; + data.setElem(offset, sample); + } + + /** + * Tests this sample model for equality with an arbitrary object. This + * method returns <code>true</code> if and only if: + * <ul> + * <li><code>obj</code> is not <code>null</code>; + * <li><code>obj</code> is an instance of + * <code>MultiPixelPackedSampleModel</code>; + * <li>both models have the same: + * <ul> + * <li><code>dataType</code>; + * <li><code>width</code>; + * <li><code>height</code>; + * <li><code>numberOfBits</code>; + * <li><code>scanlineStride</code>; + * <li><code>dataBitOffsets</code>. + * </ul> + * </li> + * </ul> + * + * @param obj the object (<code>null</code> permitted) + * + * @return <code>true</code> if this model is equal to <code>obj</code>, and + * <code>false</code> otherwise. + */ + public boolean equals(Object obj) + { + if (this == obj) + return true; + if (! (obj instanceof MultiPixelPackedSampleModel)) + return false; + MultiPixelPackedSampleModel that = (MultiPixelPackedSampleModel) obj; + if (this.dataType != that.dataType) + return false; + if (this.width != that.width) + return false; + if (this.height != that.height) + return false; + if (this.numberOfBits != that.numberOfBits) + return false; + if (this.scanlineStride != that.scanlineStride) + return false; + if (this.dataBitOffset != that.dataBitOffset) + return false; + return true; + } + + /** + * Returns a hash code for this <code>MultiPixelPackedSampleModel</code>. + * + * @return A hash code. + */ + public int hashCode() + { + // this hash code won't match Sun's, but that shouldn't matter... + int result = 193; + result = 37 * result + dataType; + result = 37 * result + width; + result = 37 * result + height; + result = 37 * result + numberOfBits; + result = 37 * result + scanlineStride; + result = 37 * result + dataBitOffset; + return result; + } + + /** + * Creates a String with some information about this SampleModel. + * @return A String describing this SampleModel. + * @see java.lang.Object#toString() + */ + public String toString() + { + CPStringBuilder result = new CPStringBuilder(); + result.append(getClass().getName()); + result.append("["); + result.append("scanlineStride=").append(scanlineStride); + for(int i=0; i < bitMasks.length; i+=1) + { + result.append(", mask[").append(i).append("]=0x").append(Integer.toHexString(bitMasks[i])); + } + + result.append("]"); + return result.toString(); + } +} |