1 /* 2 * Copyright (C) 2006 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.graphics; 18 19 import android.os.Parcel; 20 import android.os.Parcelable; 21 import android.util.DisplayMetrics; 22 23 import java.io.OutputStream; 24 import java.nio.Buffer; 25 import java.nio.ByteBuffer; 26 import java.nio.IntBuffer; 27 import java.nio.ShortBuffer; 28 29 public final class Bitmap implements Parcelable { 30 /** 31 * Indicates that the bitmap was created for an unknown pixel density. 32 * 33 * @see Bitmap#getDensity() 34 * @see Bitmap#setDensity(int) 35 */ 36 public static final int DENSITY_NONE = 0; 37 38 // Note: mNativeBitmap is used by FaceDetector_jni.cpp 39 // Don't change/rename without updating FaceDetector_jni.cpp 40 private final int mNativeBitmap; 41 42 private final boolean mIsMutable; 43 private byte[] mNinePatchChunk; // may be null 44 private int mWidth = -1; 45 private int mHeight = -1; 46 private boolean mRecycled; 47 48 // Package-scoped for fast access. 49 /*package*/ int mDensity = sDefaultDensity = getDefaultDensity(); 50 51 private static volatile Matrix sScaleMatrix; 52 53 private static volatile int sDefaultDensity = -1; 54 55 /** 56 * For backwards compatibility, allows the app layer to change the default 57 * density when running old apps. 58 * @hide 59 */ 60 public static void setDefaultDensity(int density) { 61 sDefaultDensity = density; 62 } 63 64 /*package*/ static int getDefaultDensity() { 65 if (sDefaultDensity >= 0) { 66 return sDefaultDensity; 67 } 68 sDefaultDensity = DisplayMetrics.DENSITY_DEVICE; 69 return sDefaultDensity; 70 } 71 72 /** 73 * @noinspection UnusedDeclaration 74 */ 75 /* Private constructor that must received an already allocated native 76 bitmap int (pointer). 77 78 This can be called from JNI code. 79 */ 80 private Bitmap(int nativeBitmap, boolean isMutable, byte[] ninePatchChunk, 81 int density) { 82 if (nativeBitmap == 0) { 83 throw new RuntimeException("internal error: native bitmap is 0"); 84 } 85 86 // we delete this in our finalizer 87 mNativeBitmap = nativeBitmap; 88 mIsMutable = isMutable; 89 mNinePatchChunk = ninePatchChunk; 90 if (density >= 0) { 91 mDensity = density; 92 } 93 } 94 95 /** 96 * <p>Returns the density for this bitmap.</p> 97 * 98 * <p>The default density is the same density as the current display, 99 * unless the current application does not support different screen 100 * densities in which case it is 101 * {@link android.util.DisplayMetrics#DENSITY_DEFAULT}. Note that 102 * compatibility mode is determined by the application that was initially 103 * loaded into a process -- applications that share the same process should 104 * all have the same compatibility, or ensure they explicitly set the 105 * density of their bitmaps appropriately.</p> 106 * 107 * @return A scaling factor of the default density or {@link #DENSITY_NONE} 108 * if the scaling factor is unknown. 109 * 110 * @see #setDensity(int) 111 * @see android.util.DisplayMetrics#DENSITY_DEFAULT 112 * @see android.util.DisplayMetrics#densityDpi 113 * @see #DENSITY_NONE 114 */ 115 public int getDensity() { 116 return mDensity; 117 } 118 119 /** 120 * <p>Specifies the density for this bitmap. When the bitmap is 121 * drawn to a Canvas that also has a density, it will be scaled 122 * appropriately.</p> 123 * 124 * @param density The density scaling factor to use with this bitmap or 125 * {@link #DENSITY_NONE} if the density is unknown. 126 * 127 * @see #getDensity() 128 * @see android.util.DisplayMetrics#DENSITY_DEFAULT 129 * @see android.util.DisplayMetrics#densityDpi 130 * @see #DENSITY_NONE 131 */ 132 public void setDensity(int density) { 133 mDensity = density; 134 } 135 136 /** 137 * Sets the nine patch chunk. 138 * 139 * @param chunk The definition of the nine patch 140 * 141 * @hide 142 */ 143 public void setNinePatchChunk(byte[] chunk) { 144 mNinePatchChunk = chunk; 145 } 146 147 /** 148 * Free up the memory associated with this bitmap's pixels, and mark the 149 * bitmap as "dead", meaning it will throw an exception if getPixels() or 150 * setPixels() is called, and will draw nothing. This operation cannot be 151 * reversed, so it should only be called if you are sure there are no 152 * further uses for the bitmap. This is an advanced call, and normally need 153 * not be called, since the normal GC process will free up this memory when 154 * there are no more references to this bitmap. 155 */ 156 public void recycle() { 157 if (!mRecycled) { 158 nativeRecycle(mNativeBitmap); 159 mNinePatchChunk = null; 160 mRecycled = true; 161 } 162 } 163 164 /** 165 * Returns true if this bitmap has been recycled. If so, then it is an error 166 * to try to access its pixels, and the bitmap will not draw. 167 * 168 * @return true if the bitmap has been recycled 169 */ 170 public final boolean isRecycled() { 171 return mRecycled; 172 } 173 174 /** 175 * This is called by methods that want to throw an exception if the bitmap 176 * has already been recycled. 177 */ 178 private void checkRecycled(String errorMessage) { 179 if (mRecycled) { 180 throw new IllegalStateException(errorMessage); 181 } 182 } 183 184 /** 185 * Common code for checking that x and y are >= 0 186 * 187 * @param x x coordinate to ensure is >= 0 188 * @param y y coordinate to ensure is >= 0 189 */ 190 private static void checkXYSign(int x, int y) { 191 if (x < 0) { 192 throw new IllegalArgumentException("x must be >= 0"); 193 } 194 if (y < 0) { 195 throw new IllegalArgumentException("y must be >= 0"); 196 } 197 } 198 199 /** 200 * Common code for checking that width and height are > 0 201 * 202 * @param width width to ensure is > 0 203 * @param height height to ensure is > 0 204 */ 205 private static void checkWidthHeight(int width, int height) { 206 if (width <= 0) { 207 throw new IllegalArgumentException("width must be > 0"); 208 } 209 if (height <= 0) { 210 throw new IllegalArgumentException("height must be > 0"); 211 } 212 } 213 214 public enum Config { 215 // these native values must match up with the enum in SkBitmap.h 216 ALPHA_8 (2), 217 RGB_565 (4), 218 ARGB_4444 (5), 219 ARGB_8888 (6); 220 221 Config(int ni) { 222 this.nativeInt = ni; 223 } 224 final int nativeInt; 225 226 /* package */ static Config nativeToConfig(int ni) { 227 return sConfigs[ni]; 228 } 229 230 private static Config sConfigs[] = { 231 null, null, ALPHA_8, null, RGB_565, ARGB_4444, ARGB_8888 232 }; 233 } 234 235 /** 236 * Copy the bitmap's pixels into the specified buffer (allocated by the 237 * caller). An exception is thrown if the buffer is not large enough to 238 * hold all of the pixels (taking into account the number of bytes per 239 * pixel) or if the Buffer subclass is not one of the support types 240 * (ByteBuffer, ShortBuffer, IntBuffer). 241 */ 242 public void copyPixelsToBuffer(Buffer dst) { 243 int elements = dst.remaining(); 244 int shift; 245 if (dst instanceof ByteBuffer) { 246 shift = 0; 247 } else if (dst instanceof ShortBuffer) { 248 shift = 1; 249 } else if (dst instanceof IntBuffer) { 250 shift = 2; 251 } else { 252 throw new RuntimeException("unsupported Buffer subclass"); 253 } 254 255 long bufferSize = (long)elements << shift; 256 long pixelSize = (long)getRowBytes() * getHeight(); 257 258 if (bufferSize < pixelSize) { 259 throw new RuntimeException("Buffer not large enough for pixels"); 260 } 261 262 nativeCopyPixelsToBuffer(mNativeBitmap, dst); 263 264 // now update the buffer's position 265 int position = dst.position(); 266 position += pixelSize >> shift; 267 dst.position(position); 268 } 269 270 /** 271 * Copy the pixels from the buffer, beginning at the current position, 272 * overwriting the bitmap's pixels. The data in the buffer is not changed 273 * in any way (unlike setPixels(), which converts from unpremultipled 32bit 274 * to whatever the bitmap's native format is. 275 */ 276 public void copyPixelsFromBuffer(Buffer src) { 277 checkRecycled("copyPixelsFromBuffer called on recycled bitmap"); 278 279 int elements = src.remaining(); 280 int shift; 281 if (src instanceof ByteBuffer) { 282 shift = 0; 283 } else if (src instanceof ShortBuffer) { 284 shift = 1; 285 } else if (src instanceof IntBuffer) { 286 shift = 2; 287 } else { 288 throw new RuntimeException("unsupported Buffer subclass"); 289 } 290 291 long bufferBytes = (long)elements << shift; 292 long bitmapBytes = (long)getRowBytes() * getHeight(); 293 294 if (bufferBytes < bitmapBytes) { 295 throw new RuntimeException("Buffer not large enough for pixels"); 296 } 297 298 nativeCopyPixelsFromBuffer(mNativeBitmap, src); 299 } 300 301 /** 302 * Tries to make a new bitmap based on the dimensions of this bitmap, 303 * setting the new bitmap's config to the one specified, and then copying 304 * this bitmap's pixels into the new bitmap. If the conversion is not 305 * supported, or the allocator fails, then this returns NULL. The returned 306 * bitmap initially has the same density as the original. 307 * 308 * @param config The desired config for the resulting bitmap 309 * @param isMutable True if the resulting bitmap should be mutable (i.e. 310 * its pixels can be modified) 311 * @return the new bitmap, or null if the copy could not be made. 312 */ 313 public Bitmap copy(Config config, boolean isMutable) { 314 checkRecycled("Can't copy a recycled bitmap"); 315 Bitmap b = nativeCopy(mNativeBitmap, config.nativeInt, isMutable); 316 if (b != null) { 317 b.mDensity = mDensity; 318 } 319 return b; 320 } 321 322 public static Bitmap createScaledBitmap(Bitmap src, int dstWidth, 323 int dstHeight, boolean filter) { 324 Matrix m; 325 synchronized (Bitmap.class) { 326 // small pool of just 1 matrix 327 m = sScaleMatrix; 328 sScaleMatrix = null; 329 } 330 331 if (m == null) { 332 m = new Matrix(); 333 } 334 335 final int width = src.getWidth(); 336 final int height = src.getHeight(); 337 final float sx = dstWidth / (float)width; 338 final float sy = dstHeight / (float)height; 339 m.setScale(sx, sy); 340 Bitmap b = Bitmap.createBitmap(src, 0, 0, width, height, m, filter); 341 342 synchronized (Bitmap.class) { 343 // do we need to check for null? why not just assign everytime? 344 if (sScaleMatrix == null) { 345 sScaleMatrix = m; 346 } 347 } 348 349 return b; 350 } 351 352 /** 353 * Returns an immutable bitmap from the source bitmap. The new bitmap may 354 * be the same object as source, or a copy may have been made. It is 355 * initialized with the same density as the original bitmap. 356 */ 357 public static Bitmap createBitmap(Bitmap src) { 358 return createBitmap(src, 0, 0, src.getWidth(), src.getHeight()); 359 } 360 361 /** 362 * Returns an immutable bitmap from the specified subset of the source 363 * bitmap. The new bitmap may be the same object as source, or a copy may 364 * have been made. It is 365 * initialized with the same density as the original bitmap. 366 * 367 * @param source The bitmap we are subsetting 368 * @param x The x coordinate of the first pixel in source 369 * @param y The y coordinate of the first pixel in source 370 * @param width The number of pixels in each row 371 * @param height The number of rows 372 */ 373 public static Bitmap createBitmap(Bitmap source, int x, int y, int width, int height) { 374 return createBitmap(source, x, y, width, height, null, false); 375 } 376 377 /** 378 * Returns an immutable bitmap from subset of the source bitmap, 379 * transformed by the optional matrix. It is 380 * initialized with the same density as the original bitmap. 381 * 382 * @param source The bitmap we are subsetting 383 * @param x The x coordinate of the first pixel in source 384 * @param y The y coordinate of the first pixel in source 385 * @param width The number of pixels in each row 386 * @param height The number of rows 387 * @param m Optional matrix to be applied to the pixels 388 * @param filter true if the source should be filtered. 389 * Only applies if the matrix contains more than just 390 * translation. 391 * @return A bitmap that represents the specified subset of source 392 * @throws IllegalArgumentException if the x, y, width, height values are 393 * outside of the dimensions of the source bitmap. 394 */ 395 public static Bitmap createBitmap(Bitmap source, int x, int y, int width, int height, 396 Matrix m, boolean filter) { 397 398 checkXYSign(x, y); 399 checkWidthHeight(width, height); 400 if (x + width > source.getWidth()) { 401 throw new IllegalArgumentException("x + width must be <= bitmap.width()"); 402 } 403 if (y + height > source.getHeight()) { 404 throw new IllegalArgumentException("y + height must be <= bitmap.height()"); 405 } 406 407 // check if we can just return our argument unchanged 408 if (!source.isMutable() && x == 0 && y == 0 && width == source.getWidth() && 409 height == source.getHeight() && (m == null || m.isIdentity())) { 410 return source; 411 } 412 413 int neww = width; 414 int newh = height; 415 Canvas canvas = new Canvas(); 416 Bitmap bitmap; 417 Paint paint; 418 419 Rect srcR = new Rect(x, y, x + width, y + height); 420 RectF dstR = new RectF(0, 0, width, height); 421 422 if (m == null || m.isIdentity()) { 423 bitmap = createBitmap(neww, newh, 424 source.hasAlpha() ? Config.ARGB_8888 : Config.RGB_565); 425 paint = null; // not needed 426 } else { 427 /* the dst should have alpha if the src does, or if our matrix 428 doesn't preserve rectness 429 */ 430 boolean hasAlpha = source.hasAlpha() || !m.rectStaysRect(); 431 RectF deviceR = new RectF(); 432 m.mapRect(deviceR, dstR); 433 neww = Math.round(deviceR.width()); 434 newh = Math.round(deviceR.height()); 435 bitmap = createBitmap(neww, newh, hasAlpha ? Config.ARGB_8888 : Config.RGB_565); 436 if (hasAlpha) { 437 bitmap.eraseColor(0); 438 } 439 canvas.translate(-deviceR.left, -deviceR.top); 440 canvas.concat(m); 441 paint = new Paint(); 442 paint.setFilterBitmap(filter); 443 if (!m.rectStaysRect()) { 444 paint.setAntiAlias(true); 445 } 446 } 447 448 // The new bitmap was created from a known bitmap source so assume that 449 // they use the same density 450 bitmap.mDensity = source.mDensity; 451 452 canvas.setBitmap(bitmap); 453 canvas.drawBitmap(source, srcR, dstR, paint); 454 455 return bitmap; 456 } 457 458 /** 459 * Returns a mutable bitmap with the specified width and height. Its 460 * initial density is as per {@link #getDensity}. 461 * 462 * @param width The width of the bitmap 463 * @param height The height of the bitmap 464 * @param config The bitmap config to create. 465 * @throws IllegalArgumentException if the width or height are <= 0 466 */ 467 public static Bitmap createBitmap(int width, int height, Config config) { 468 Bitmap bm = nativeCreate(null, 0, width, width, height, config.nativeInt, true); 469 bm.eraseColor(0); // start with black/transparent pixels 470 return bm; 471 } 472 473 /** 474 * Returns a immutable bitmap with the specified width and height, with each 475 * pixel value set to the corresponding value in the colors array. Its 476 * initial density is as per {@link #getDensity}. 477 * 478 * @param colors Array of {@link Color} used to initialize the pixels. 479 * @param offset Number of values to skip before the first color in the 480 * array of colors. 481 * @param stride Number of colors in the array between rows (must be >= 482 * width or <= -width). 483 * @param width The width of the bitmap 484 * @param height The height of the bitmap 485 * @param config The bitmap config to create. If the config does not 486 * support per-pixel alpha (e.g. RGB_565), then the alpha 487 * bytes in the colors[] will be ignored (assumed to be FF) 488 * @throws IllegalArgumentException if the width or height are <= 0, or if 489 * the color array's length is less than the number of pixels. 490 */ 491 public static Bitmap createBitmap(int colors[], int offset, int stride, 492 int width, int height, Config config) { 493 494 checkWidthHeight(width, height); 495 if (Math.abs(stride) < width) { 496 throw new IllegalArgumentException("abs(stride) must be >= width"); 497 } 498 int lastScanline = offset + (height - 1) * stride; 499 int length = colors.length; 500 if (offset < 0 || (offset + width > length) || lastScanline < 0 || 501 (lastScanline + width > length)) { 502 throw new ArrayIndexOutOfBoundsException(); 503 } 504 return nativeCreate(colors, offset, stride, width, height, 505 config.nativeInt, false); 506 } 507 508 /** 509 * Returns a immutable bitmap with the specified width and height, with each 510 * pixel value set to the corresponding value in the colors array. Its 511 * initial density is as per {@link #getDensity}. 512 * 513 * @param colors Array of {@link Color} used to initialize the pixels. 514 * This array must be at least as large as width * height. 515 * @param width The width of the bitmap 516 * @param height The height of the bitmap 517 * @param config The bitmap config to create. If the config does not 518 * support per-pixel alpha (e.g. RGB_565), then the alpha 519 * bytes in the colors[] will be ignored (assumed to be FF) 520 * @throws IllegalArgumentException if the width or height are <= 0, or if 521 * the color array's length is less than the number of pixels. 522 */ 523 public static Bitmap createBitmap(int colors[], int width, int height, Config config) { 524 return createBitmap(colors, 0, width, width, height, config); 525 } 526 527 /** 528 * Returns an optional array of private data, used by the UI system for 529 * some bitmaps. Not intended to be called by applications. 530 */ 531 public byte[] getNinePatchChunk() { 532 return mNinePatchChunk; 533 } 534 535 /** 536 * Specifies the known formats a bitmap can be compressed into 537 */ 538 public enum CompressFormat { 539 JPEG (0), 540 PNG (1); 541 542 CompressFormat(int nativeInt) { 543 this.nativeInt = nativeInt; 544 } 545 final int nativeInt; 546 } 547 548 /** 549 * Number of bytes of temp storage we use for communicating between the 550 * native compressor and the java OutputStream. 551 */ 552 private final static int WORKING_COMPRESS_STORAGE = 4096; 553 554 /** 555 * Write a compressed version of the bitmap to the specified outputstream. 556 * If this returns true, the bitmap can be reconstructed by passing a 557 * corresponding inputstream to BitmapFactory.decodeStream(). Note: not 558 * all Formats support all bitmap configs directly, so it is possible that 559 * the returned bitmap from BitmapFactory could be in a different bitdepth, 560 * and/or may have lost per-pixel alpha (e.g. JPEG only supports opaque 561 * pixels). 562 * 563 * @param format The format of the compressed image 564 * @param quality Hint to the compressor, 0-100. 0 meaning compress for 565 * small size, 100 meaning compress for max quality. Some 566 * formats, like PNG which is lossless, will ignore the 567 * quality setting 568 * @param stream The outputstream to write the compressed data. 569 * @return true if successfully compressed to the specified stream. 570 */ 571 public boolean compress(CompressFormat format, int quality, OutputStream stream) { 572 checkRecycled("Can't compress a recycled bitmap"); 573 // do explicit check before calling the native method 574 if (stream == null) { 575 throw new NullPointerException(); 576 } 577 if (quality < 0 || quality > 100) { 578 throw new IllegalArgumentException("quality must be 0..100"); 579 } 580 return nativeCompress(mNativeBitmap, format.nativeInt, quality, 581 stream, new byte[WORKING_COMPRESS_STORAGE]); 582 } 583 584 /** 585 * Returns true if the bitmap is marked as mutable (i.e. can be drawn into) 586 */ 587 public final boolean isMutable() { 588 return mIsMutable; 589 } 590 591 /** Returns the bitmap's width */ 592 public final int getWidth() { 593 return mWidth == -1 ? mWidth = nativeWidth(mNativeBitmap) : mWidth; 594 } 595 596 /** Returns the bitmap's height */ 597 public final int getHeight() { 598 return mHeight == -1 ? mHeight = nativeHeight(mNativeBitmap) : mHeight; 599 } 600 601 /** 602 * Convenience for calling {@link #getScaledWidth(int)} with the target 603 * density of the given {@link Canvas}. 604 */ 605 public int getScaledWidth(Canvas canvas) { 606 return scaleFromDensity(getWidth(), mDensity, canvas.mDensity); 607 } 608 609 /** 610 * Convenience for calling {@link #getScaledHeight(int)} with the target 611 * density of the given {@link Canvas}. 612 */ 613 public int getScaledHeight(Canvas canvas) { 614 return scaleFromDensity(getHeight(), mDensity, canvas.mDensity); 615 } 616 617 /** 618 * Convenience for calling {@link #getScaledWidth(int)} with the target 619 * density of the given {@link DisplayMetrics}. 620 */ 621 public int getScaledWidth(DisplayMetrics metrics) { 622 return scaleFromDensity(getWidth(), mDensity, metrics.densityDpi); 623 } 624 625 /** 626 * Convenience for calling {@link #getScaledHeight(int)} with the target 627 * density of the given {@link DisplayMetrics}. 628 */ 629 public int getScaledHeight(DisplayMetrics metrics) { 630 return scaleFromDensity(getHeight(), mDensity, metrics.densityDpi); 631 } 632 633 /** 634 * Convenience method that returns the width of this bitmap divided 635 * by the density scale factor. 636 * 637 * @param targetDensity The density of the target canvas of the bitmap. 638 * @return The scaled width of this bitmap, according to the density scale factor. 639 */ 640 public int getScaledWidth(int targetDensity) { 641 return scaleFromDensity(getWidth(), mDensity, targetDensity); 642 } 643 644 /** 645 * Convenience method that returns the height of this bitmap divided 646 * by the density scale factor. 647 * 648 * @param targetDensity The density of the target canvas of the bitmap. 649 * @return The scaled height of this bitmap, according to the density scale factor. 650 */ 651 public int getScaledHeight(int targetDensity) { 652 return scaleFromDensity(getHeight(), mDensity, targetDensity); 653 } 654 655 /** 656 * @hide 657 */ 658 static public int scaleFromDensity(int size, int sdensity, int tdensity) { 659 if (sdensity == DENSITY_NONE || sdensity == tdensity) { 660 return size; 661 } 662 663 // Scale by tdensity / sdensity, rounding up. 664 return ( (size * tdensity) + (sdensity >> 1) ) / sdensity; 665 } 666 667 /** 668 * Return the number of bytes between rows in the bitmap's pixels. Note that 669 * this refers to the pixels as stored natively by the bitmap. If you call 670 * getPixels() or setPixels(), then the pixels are uniformly treated as 671 * 32bit values, packed according to the Color class. 672 * 673 * @return number of bytes between rows of the native bitmap pixels. 674 */ 675 public final int getRowBytes() { 676 return nativeRowBytes(mNativeBitmap); 677 } 678 679 /** 680 * If the bitmap's internal config is in one of the public formats, return 681 * that config, otherwise return null. 682 */ 683 public final Config getConfig() { 684 return Config.nativeToConfig(nativeConfig(mNativeBitmap)); 685 } 686 687 /** Returns true if the bitmap's config supports per-pixel alpha, and 688 * if the pixels may contain non-opaque alpha values. For some configs, 689 * this is always false (e.g. RGB_565), since they do not support per-pixel 690 * alpha. However, for configs that do, the bitmap may be flagged to be 691 * known that all of its pixels are opaque. In this case hasAlpha() will 692 * also return false. If a config such as ARGB_8888 is not so flagged, 693 * it will return true by default. 694 */ 695 public final boolean hasAlpha() { 696 return nativeHasAlpha(mNativeBitmap); 697 } 698 699 /** 700 * Tell the bitmap if all of the pixels are known to be opaque (false) 701 * or if some of the pixels may contain non-opaque alpha values (true). 702 * Note, for some configs (e.g. RGB_565) this call is ignore, since it does 703 * not support per-pixel alpha values. 704 * 705 * This is meant as a drawing hint, as in some cases a bitmap that is known 706 * to be opaque can take a faster drawing case than one that may have 707 * non-opaque per-pixel alpha values. 708 * 709 * @hide 710 */ 711 public void setHasAlpha(boolean hasAlpha) { 712 nativeSetHasAlpha(mNativeBitmap, hasAlpha); 713 } 714 715 /** 716 * Fills the bitmap's pixels with the specified {@link Color}. 717 * 718 * @throws IllegalStateException if the bitmap is not mutable. 719 */ 720 public void eraseColor(int c) { 721 checkRecycled("Can't erase a recycled bitmap"); 722 if (!isMutable()) { 723 throw new IllegalStateException("cannot erase immutable bitmaps"); 724 } 725 nativeErase(mNativeBitmap, c); 726 } 727 728 /** 729 * Returns the {@link Color} at the specified location. Throws an exception 730 * if x or y are out of bounds (negative or >= to the width or height 731 * respectively). 732 * 733 * @param x The x coordinate (0...width-1) of the pixel to return 734 * @param y The y coordinate (0...height-1) of the pixel to return 735 * @return The argb {@link Color} at the specified coordinate 736 * @throws IllegalArgumentException if x, y exceed the bitmap's bounds 737 */ 738 public int getPixel(int x, int y) { 739 checkRecycled("Can't call getPixel() on a recycled bitmap"); 740 checkPixelAccess(x, y); 741 return nativeGetPixel(mNativeBitmap, x, y); 742 } 743 744 /** 745 * Returns in pixels[] a copy of the data in the bitmap. Each value is 746 * a packed int representing a {@link Color}. The stride parameter allows 747 * the caller to allow for gaps in the returned pixels array between 748 * rows. For normal packed results, just pass width for the stride value. 749 * 750 * @param pixels The array to receive the bitmap's colors 751 * @param offset The first index to write into pixels[] 752 * @param stride The number of entries in pixels[] to skip between 753 * rows (must be >= bitmap's width). Can be negative. 754 * @param x The x coordinate of the first pixel to read from 755 * the bitmap 756 * @param y The y coordinate of the first pixel to read from 757 * the bitmap 758 * @param width The number of pixels to read from each row 759 * @param height The number of rows to read 760 * @throws IllegalArgumentException if x, y, width, height exceed the 761 * bounds of the bitmap, or if abs(stride) < width. 762 * @throws ArrayIndexOutOfBoundsException if the pixels array is too small 763 * to receive the specified number of pixels. 764 */ 765 public void getPixels(int[] pixels, int offset, int stride, 766 int x, int y, int width, int height) { 767 checkRecycled("Can't call getPixels() on a recycled bitmap"); 768 if (width == 0 || height == 0) { 769 return; // nothing to do 770 } 771 checkPixelsAccess(x, y, width, height, offset, stride, pixels); 772 nativeGetPixels(mNativeBitmap, pixels, offset, stride, 773 x, y, width, height); 774 } 775 776 /** 777 * Shared code to check for illegal arguments passed to getPixel() 778 * or setPixel() 779 * @param x x coordinate of the pixel 780 * @param y y coordinate of the pixel 781 */ 782 private void checkPixelAccess(int x, int y) { 783 checkXYSign(x, y); 784 if (x >= getWidth()) { 785 throw new IllegalArgumentException("x must be < bitmap.width()"); 786 } 787 if (y >= getHeight()) { 788 throw new IllegalArgumentException("y must be < bitmap.height()"); 789 } 790 } 791 792 /** 793 * Shared code to check for illegal arguments passed to getPixels() 794 * or setPixels() 795 * 796 * @param x left edge of the area of pixels to access 797 * @param y top edge of the area of pixels to access 798 * @param width width of the area of pixels to access 799 * @param height height of the area of pixels to access 800 * @param offset offset into pixels[] array 801 * @param stride number of elements in pixels[] between each logical row 802 * @param pixels array to hold the area of pixels being accessed 803 */ 804 private void checkPixelsAccess(int x, int y, int width, int height, 805 int offset, int stride, int pixels[]) { 806 checkXYSign(x, y); 807 if (width < 0) { 808 throw new IllegalArgumentException("width must be >= 0"); 809 } 810 if (height < 0) { 811 throw new IllegalArgumentException("height must be >= 0"); 812 } 813 if (x + width > getWidth()) { 814 throw new IllegalArgumentException( 815 "x + width must be <= bitmap.width()"); 816 } 817 if (y + height > getHeight()) { 818 throw new IllegalArgumentException( 819 "y + height must be <= bitmap.height()"); 820 } 821 if (Math.abs(stride) < width) { 822 throw new IllegalArgumentException("abs(stride) must be >= width"); 823 } 824 int lastScanline = offset + (height - 1) * stride; 825 int length = pixels.length; 826 if (offset < 0 || (offset + width > length) 827 || lastScanline < 0 828 || (lastScanline + width > length)) { 829 throw new ArrayIndexOutOfBoundsException(); 830 } 831 } 832 833 /** 834 * Write the specified {@link Color} into the bitmap (assuming it is 835 * mutable) at the x,y coordinate. 836 * 837 * @param x The x coordinate of the pixel to replace (0...width-1) 838 * @param y The y coordinate of the pixel to replace (0...height-1) 839 * @param color The {@link Color} to write into the bitmap 840 * @throws IllegalStateException if the bitmap is not mutable 841 * @throws IllegalArgumentException if x, y are outside of the bitmap's 842 * bounds. 843 */ 844 public void setPixel(int x, int y, int color) { 845 checkRecycled("Can't call setPixel() on a recycled bitmap"); 846 if (!isMutable()) { 847 throw new IllegalStateException(); 848 } 849 checkPixelAccess(x, y); 850 nativeSetPixel(mNativeBitmap, x, y, color); 851 } 852 853 /** 854 * Replace pixels in the bitmap with the colors in the array. Each element 855 * in the array is a packed int prepresenting a {@link Color} 856 * 857 * @param pixels The colors to write to the bitmap 858 * @param offset The index of the first color to read from pixels[] 859 * @param stride The number of colors in pixels[] to skip between rows. 860 * Normally this value will be the same as the width of 861 * the bitmap, but it can be larger (or negative). 862 * @param x The x coordinate of the first pixel to write to in 863 * the bitmap. 864 * @param y The y coordinate of the first pixel to write to in 865 * the bitmap. 866 * @param width The number of colors to copy from pixels[] per row 867 * @param height The number of rows to write to the bitmap 868 * @throws IllegalStateException if the bitmap is not mutable 869 * @throws IllegalArgumentException if x, y, width, height are outside of 870 * the bitmap's bounds. 871 * @throws ArrayIndexOutOfBoundsException if the pixels array is too small 872 * to receive the specified number of pixels. 873 */ 874 public void setPixels(int[] pixels, int offset, int stride, 875 int x, int y, int width, int height) { 876 checkRecycled("Can't call setPixels() on a recycled bitmap"); 877 if (!isMutable()) { 878 throw new IllegalStateException(); 879 } 880 if (width == 0 || height == 0) { 881 return; // nothing to do 882 } 883 checkPixelsAccess(x, y, width, height, offset, stride, pixels); 884 nativeSetPixels(mNativeBitmap, pixels, offset, stride, 885 x, y, width, height); 886 } 887 888 public static final Parcelable.Creator<Bitmap> CREATOR 889 = new Parcelable.Creator<Bitmap>() { 890 /** 891 * Rebuilds a bitmap previously stored with writeToParcel(). 892 * 893 * @param p Parcel object to read the bitmap from 894 * @return a new bitmap created from the data in the parcel 895 */ 896 public Bitmap createFromParcel(Parcel p) { 897 Bitmap bm = nativeCreateFromParcel(p); 898 if (bm == null) { 899 throw new RuntimeException("Failed to unparcel Bitmap"); 900 } 901 return bm; 902 } 903 public Bitmap[] newArray(int size) { 904 return new Bitmap[size]; 905 } 906 }; 907 908 /** 909 * No special parcel contents. 910 */ 911 public int describeContents() { 912 return 0; 913 } 914 915 /** 916 * Write the bitmap and its pixels to the parcel. The bitmap can be 917 * rebuilt from the parcel by calling CREATOR.createFromParcel(). 918 * @param p Parcel object to write the bitmap data into 919 */ 920 public void writeToParcel(Parcel p, int flags) { 921 checkRecycled("Can't parcel a recycled bitmap"); 922 if (!nativeWriteToParcel(mNativeBitmap, mIsMutable, mDensity, p)) { 923 throw new RuntimeException("native writeToParcel failed"); 924 } 925 } 926 927 /** 928 * Returns a new bitmap that captures the alpha values of the original. 929 * This may be drawn with Canvas.drawBitmap(), where the color(s) will be 930 * taken from the paint that is passed to the draw call. 931 * 932 * @return new bitmap containing the alpha channel of the original bitmap. 933 */ 934 public Bitmap extractAlpha() { 935 return extractAlpha(null, null); 936 } 937 938 /** 939 * Returns a new bitmap that captures the alpha values of the original. 940 * These values may be affected by the optional Paint parameter, which 941 * can contain its own alpha, and may also contain a MaskFilter which 942 * could change the actual dimensions of the resulting bitmap (e.g. 943 * a blur maskfilter might enlarge the resulting bitmap). If offsetXY 944 * is not null, it returns the amount to offset the returned bitmap so 945 * that it will logically align with the original. For example, if the 946 * paint contains a blur of radius 2, then offsetXY[] would contains 947 * -2, -2, so that drawing the alpha bitmap offset by (-2, -2) and then 948 * drawing the original would result in the blur visually aligning with 949 * the original. 950 * 951 * <p>The initial density of the returned bitmap is the same as the original's. 952 * 953 * @param paint Optional paint used to modify the alpha values in the 954 * resulting bitmap. Pass null for default behavior. 955 * @param offsetXY Optional array that returns the X (index 0) and Y 956 * (index 1) offset needed to position the returned bitmap 957 * so that it visually lines up with the original. 958 * @return new bitmap containing the (optionally modified by paint) alpha 959 * channel of the original bitmap. This may be drawn with 960 * Canvas.drawBitmap(), where the color(s) will be taken from the 961 * paint that is passed to the draw call. 962 */ 963 public Bitmap extractAlpha(Paint paint, int[] offsetXY) { 964 checkRecycled("Can't extractAlpha on a recycled bitmap"); 965 int nativePaint = paint != null ? paint.mNativePaint : 0; 966 Bitmap bm = nativeExtractAlpha(mNativeBitmap, nativePaint, offsetXY); 967 if (bm == null) { 968 throw new RuntimeException("Failed to extractAlpha on Bitmap"); 969 } 970 bm.mDensity = mDensity; 971 return bm; 972 } 973 974 /** 975 * Given another bitmap, return true if it has the same dimensions, config, 976 * and pixel data as this bitmap. If any of those differ, return false. 977 * If other is null, return false. 978 * 979 * @hide (just needed internally right now) 980 */ 981 public boolean sameAs(Bitmap other) { 982 return this == other || 983 (other != null && 984 nativeSameAs(mNativeBitmap, other.mNativeBitmap)); 985 } 986 987 /** 988 * Rebuilds any caches associated with the bitmap that are used for 989 * drawing it. In the case of purgeable bitmaps, this call will attempt to 990 * ensure that the pixels have been decoded. 991 * If this is called on more than one bitmap in sequence, the priority is 992 * given in LRU order (i.e. the last bitmap called will be given highest 993 * priority). 994 * 995 * For bitmaps with no associated caches, this call is effectively a no-op, 996 * and therefore is harmless. 997 */ 998 public void prepareToDraw() { 999 nativePrepareToDraw(mNativeBitmap); 1000 } 1001 1002 @Override 1003 protected void finalize() throws Throwable { 1004 try { 1005 nativeDestructor(mNativeBitmap); 1006 } finally { 1007 super.finalize(); 1008 } 1009 } 1010 1011 //////////// native methods 1012 1013 private static native Bitmap nativeCreate(int[] colors, int offset, 1014 int stride, int width, int height, 1015 int nativeConfig, boolean mutable); 1016 private static native Bitmap nativeCopy(int srcBitmap, int nativeConfig, 1017 boolean isMutable); 1018 private static native void nativeDestructor(int nativeBitmap); 1019 private static native void nativeRecycle(int nativeBitmap); 1020 1021 private static native boolean nativeCompress(int nativeBitmap, int format, 1022 int quality, OutputStream stream, 1023 byte[] tempStorage); 1024 private static native void nativeErase(int nativeBitmap, int color); 1025 private static native int nativeWidth(int nativeBitmap); 1026 private static native int nativeHeight(int nativeBitmap); 1027 private static native int nativeRowBytes(int nativeBitmap); 1028 private static native int nativeConfig(int nativeBitmap); 1029 private static native boolean nativeHasAlpha(int nativeBitmap); 1030 1031 private static native int nativeGetPixel(int nativeBitmap, int x, int y); 1032 private static native void nativeGetPixels(int nativeBitmap, int[] pixels, 1033 int offset, int stride, int x, 1034 int y, int width, int height); 1035 1036 private static native void nativeSetPixel(int nativeBitmap, int x, int y, 1037 int color); 1038 private static native void nativeSetPixels(int nativeBitmap, int[] colors, 1039 int offset, int stride, int x, 1040 int y, int width, int height); 1041 private static native void nativeCopyPixelsToBuffer(int nativeBitmap, 1042 Buffer dst); 1043 private static native void nativeCopyPixelsFromBuffer(int nb, Buffer src); 1044 1045 private static native Bitmap nativeCreateFromParcel(Parcel p); 1046 // returns true on success 1047 private static native boolean nativeWriteToParcel(int nativeBitmap, 1048 boolean isMutable, 1049 int density, 1050 Parcel p); 1051 // returns a new bitmap built from the native bitmap's alpha, and the paint 1052 private static native Bitmap nativeExtractAlpha(int nativeBitmap, 1053 int nativePaint, 1054 int[] offsetXY); 1055 1056 private static native void nativePrepareToDraw(int nativeBitmap); 1057 private static native void nativeSetHasAlpha(int nBitmap, boolean hasAlpha); 1058 private static native boolean nativeSameAs(int nb0, int nb1); 1059 1060 /* package */ final int ni() { 1061 return mNativeBitmap; 1062 } 1063 } 1064
