Canvas.java revision 0932cf87c131f9238538fd7137b282adbe71dc37
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 17package android.graphics; 18 19import android.text.GraphicsOperations; 20import android.text.SpannableString; 21import android.text.SpannedString; 22import android.text.TextUtils; 23 24/** 25 * The Canvas class holds the "draw" calls. To draw something, you need 26 * 4 basic components: A Bitmap to hold the pixels, a Canvas to host 27 * the draw calls (writing into the bitmap), a drawing primitive (e.g. Rect, 28 * Path, text, Bitmap), and a paint (to describe the colors and styles for the 29 * drawing). 30 * 31 * <div class="special reference"> 32 * <h3>Developer Guides</h3> 33 * <p>For more information about how to use Canvas, read the 34 * <a href="{@docRoot}guide/topics/graphics/2d-graphics.html"> 35 * Canvas and Drawables</a> developer guide.</p></div> 36 */ 37public class Canvas { 38 39 // assigned in constructors or setBitmap, freed in finalizer 40 /** @hide */ 41 public long mNativeCanvas; 42 43 // may be null 44 private Bitmap mBitmap; 45 46 // optional field set by the caller 47 private DrawFilter mDrawFilter; 48 49 /** 50 * @hide 51 */ 52 protected int mDensity = Bitmap.DENSITY_NONE; 53 54 /** 55 * Used to determine when compatibility scaling is in effect. 56 * 57 * @hide 58 */ 59 protected int mScreenDensity = Bitmap.DENSITY_NONE; 60 61 // Used by native code 62 @SuppressWarnings("UnusedDeclaration") 63 private int mSurfaceFormat; 64 65 /** 66 * Flag for drawTextRun indicating left-to-right run direction. 67 * @hide 68 */ 69 public static final int DIRECTION_LTR = 0; 70 71 /** 72 * Flag for drawTextRun indicating right-to-left run direction. 73 * @hide 74 */ 75 public static final int DIRECTION_RTL = 1; 76 77 // Maximum bitmap size as defined in Skia's native code 78 // (see SkCanvas.cpp, SkDraw.cpp) 79 private static final int MAXMIMUM_BITMAP_SIZE = 32766; 80 81 // This field is used to finalize the native Canvas properly 82 private final CanvasFinalizer mFinalizer; 83 84 private static final class CanvasFinalizer { 85 private long mNativeCanvas; 86 87 public CanvasFinalizer(long nativeCanvas) { 88 mNativeCanvas = nativeCanvas; 89 } 90 91 @Override 92 protected void finalize() throws Throwable { 93 try { 94 dispose(); 95 } finally { 96 super.finalize(); 97 } 98 } 99 100 public void dispose() { 101 if (mNativeCanvas != 0) { 102 finalizer(mNativeCanvas); 103 mNativeCanvas = 0; 104 } 105 } 106 } 107 108 /** 109 * Construct an empty raster canvas. Use setBitmap() to specify a bitmap to 110 * draw into. The initial target density is {@link Bitmap#DENSITY_NONE}; 111 * this will typically be replaced when a target bitmap is set for the 112 * canvas. 113 */ 114 public Canvas() { 115 if (!isHardwareAccelerated()) { 116 // 0 means no native bitmap 117 mNativeCanvas = initRaster(0); 118 mFinalizer = new CanvasFinalizer(mNativeCanvas); 119 } else { 120 mFinalizer = null; 121 } 122 } 123 124 /** 125 * Construct a canvas with the specified bitmap to draw into. The bitmap 126 * must be mutable. 127 * 128 * <p>The initial target density of the canvas is the same as the given 129 * bitmap's density. 130 * 131 * @param bitmap Specifies a mutable bitmap for the canvas to draw into. 132 */ 133 public Canvas(Bitmap bitmap) { 134 if (!bitmap.isMutable()) { 135 throw new IllegalStateException("Immutable bitmap passed to Canvas constructor"); 136 } 137 throwIfCannotDraw(bitmap); 138 mNativeCanvas = initRaster(bitmap.ni()); 139 mFinalizer = new CanvasFinalizer(mNativeCanvas); 140 mBitmap = bitmap; 141 mDensity = bitmap.mDensity; 142 } 143 144 /** @hide */ 145 public Canvas(long nativeCanvas) { 146 if (nativeCanvas == 0) { 147 throw new IllegalStateException(); 148 } 149 mNativeCanvas = nativeCanvas; 150 mFinalizer = new CanvasFinalizer(mNativeCanvas); 151 mDensity = Bitmap.getDefaultDensity(); 152 } 153 154 /** 155 * Replace existing canvas while ensuring that the swap has occurred before 156 * the previous native canvas is unreferenced. 157 */ 158 private void safeCanvasSwap(long nativeCanvas, boolean copyState) { 159 final long oldCanvas = mNativeCanvas; 160 mNativeCanvas = nativeCanvas; 161 mFinalizer.mNativeCanvas = nativeCanvas; 162 if (copyState) { 163 copyNativeCanvasState(oldCanvas, mNativeCanvas); 164 } 165 finalizer(oldCanvas); 166 } 167 168 /** 169 * Indicates whether this Canvas uses hardware acceleration. 170 * 171 * Note that this method does not define what type of hardware acceleration 172 * may or may not be used. 173 * 174 * @return True if drawing operations are hardware accelerated, 175 * false otherwise. 176 */ 177 public boolean isHardwareAccelerated() { 178 return false; 179 } 180 181 /** 182 * Specify a bitmap for the canvas to draw into. All canvas state such as 183 * layers, filters, and the save/restore stack are reset with the exception 184 * of the current matrix and clip stack. Additionally, as a side-effect 185 * the canvas' target density is updated to match that of the bitmap. 186 * 187 * @param bitmap Specifies a mutable bitmap for the canvas to draw into. 188 * @see #setDensity(int) 189 * @see #getDensity() 190 */ 191 public void setBitmap(Bitmap bitmap) { 192 if (isHardwareAccelerated()) { 193 throw new RuntimeException("Can't set a bitmap device on a GL canvas"); 194 } 195 196 if (bitmap == null) { 197 safeCanvasSwap(initRaster(0), false); 198 mDensity = Bitmap.DENSITY_NONE; 199 } else { 200 if (!bitmap.isMutable()) { 201 throw new IllegalStateException(); 202 } 203 throwIfCannotDraw(bitmap); 204 205 safeCanvasSwap(initRaster(bitmap.ni()), true); 206 mDensity = bitmap.mDensity; 207 } 208 209 mBitmap = bitmap; 210 } 211 212 /** 213 * Set the viewport dimensions if this canvas is GL based. If it is not, 214 * this method is ignored and no exception is thrown. 215 * 216 * @param width The width of the viewport 217 * @param height The height of the viewport 218 * 219 * @hide 220 */ 221 public void setViewport(int width, int height) { 222 } 223 224 /** 225 * Return true if the device that the current layer draws into is opaque 226 * (i.e. does not support per-pixel alpha). 227 * 228 * @return true if the device that the current layer draws into is opaque 229 */ 230 public native boolean isOpaque(); 231 232 /** 233 * Returns the width of the current drawing layer 234 * 235 * @return the width of the current drawing layer 236 */ 237 public native int getWidth(); 238 239 /** 240 * Returns the height of the current drawing layer 241 * 242 * @return the height of the current drawing layer 243 */ 244 public native int getHeight(); 245 246 /** 247 * <p>Returns the target density of the canvas. The default density is 248 * derived from the density of its backing bitmap, or 249 * {@link Bitmap#DENSITY_NONE} if there is not one.</p> 250 * 251 * @return Returns the current target density of the canvas, which is used 252 * to determine the scaling factor when drawing a bitmap into it. 253 * 254 * @see #setDensity(int) 255 * @see Bitmap#getDensity() 256 */ 257 public int getDensity() { 258 return mDensity; 259 } 260 261 /** 262 * <p>Specifies the density for this Canvas' backing bitmap. This modifies 263 * the target density of the canvas itself, as well as the density of its 264 * backing bitmap via {@link Bitmap#setDensity(int) Bitmap.setDensity(int)}. 265 * 266 * @param density The new target density of the canvas, which is used 267 * to determine the scaling factor when drawing a bitmap into it. Use 268 * {@link Bitmap#DENSITY_NONE} to disable bitmap scaling. 269 * 270 * @see #getDensity() 271 * @see Bitmap#setDensity(int) 272 */ 273 public void setDensity(int density) { 274 if (mBitmap != null) { 275 mBitmap.setDensity(density); 276 } 277 mDensity = density; 278 } 279 280 /** @hide */ 281 public void setScreenDensity(int density) { 282 mScreenDensity = density; 283 } 284 285 /** 286 * Returns the maximum allowed width for bitmaps drawn with this canvas. 287 * Attempting to draw with a bitmap wider than this value will result 288 * in an error. 289 * 290 * @see #getMaximumBitmapHeight() 291 */ 292 public int getMaximumBitmapWidth() { 293 return MAXMIMUM_BITMAP_SIZE; 294 } 295 296 /** 297 * Returns the maximum allowed height for bitmaps drawn with this canvas. 298 * Attempting to draw with a bitmap taller than this value will result 299 * in an error. 300 * 301 * @see #getMaximumBitmapWidth() 302 */ 303 public int getMaximumBitmapHeight() { 304 return MAXMIMUM_BITMAP_SIZE; 305 } 306 307 // the SAVE_FLAG constants must match their native equivalents 308 309 /** restore the current matrix when restore() is called */ 310 public static final int MATRIX_SAVE_FLAG = 0x01; 311 /** restore the current clip when restore() is called */ 312 public static final int CLIP_SAVE_FLAG = 0x02; 313 /** the layer needs to per-pixel alpha */ 314 public static final int HAS_ALPHA_LAYER_SAVE_FLAG = 0x04; 315 /** the layer needs to 8-bits per color component */ 316 public static final int FULL_COLOR_LAYER_SAVE_FLAG = 0x08; 317 /** clip against the layer's bounds */ 318 public static final int CLIP_TO_LAYER_SAVE_FLAG = 0x10; 319 /** restore everything when restore() is called */ 320 public static final int ALL_SAVE_FLAG = 0x1F; 321 322 /** 323 * Saves the current matrix and clip onto a private stack. Subsequent 324 * calls to translate,scale,rotate,skew,concat or clipRect,clipPath 325 * will all operate as usual, but when the balancing call to restore() 326 * is made, those calls will be forgotten, and the settings that existed 327 * before the save() will be reinstated. 328 * 329 * @return The value to pass to restoreToCount() to balance this save() 330 */ 331 public native int save(); 332 333 /** 334 * Based on saveFlags, can save the current matrix and clip onto a private 335 * stack. Subsequent calls to translate,scale,rotate,skew,concat or 336 * clipRect,clipPath will all operate as usual, but when the balancing 337 * call to restore() is made, those calls will be forgotten, and the 338 * settings that existed before the save() will be reinstated. 339 * 340 * @param saveFlags flag bits that specify which parts of the Canvas state 341 * to save/restore 342 * @return The value to pass to restoreToCount() to balance this save() 343 */ 344 public native int save(int saveFlags); 345 346 /** 347 * This behaves the same as save(), but in addition it allocates an 348 * offscreen bitmap. All drawing calls are directed there, and only when 349 * the balancing call to restore() is made is that offscreen transfered to 350 * the canvas (or the previous layer). Subsequent calls to translate, 351 * scale, rotate, skew, concat or clipRect, clipPath all operate on this 352 * copy. When the balancing call to restore() is made, this copy is 353 * deleted and the previous matrix/clip state is restored. 354 * 355 * @param bounds May be null. The maximum size the offscreen bitmap 356 * needs to be (in local coordinates) 357 * @param paint This is copied, and is applied to the offscreen when 358 * restore() is called. 359 * @param saveFlags see _SAVE_FLAG constants 360 * @return value to pass to restoreToCount() to balance this save() 361 */ 362 public int saveLayer(RectF bounds, Paint paint, int saveFlags) { 363 return native_saveLayer(mNativeCanvas, bounds, 364 paint != null ? paint.mNativePaint : 0, 365 saveFlags); 366 } 367 368 /** 369 * Convenience for saveLayer(bounds, paint, {@link #ALL_SAVE_FLAG}) 370 */ 371 public int saveLayer(RectF bounds, Paint paint) { 372 return saveLayer(bounds, paint, ALL_SAVE_FLAG); 373 } 374 375 /** 376 * Helper version of saveLayer() that takes 4 values rather than a RectF. 377 */ 378 public int saveLayer(float left, float top, float right, float bottom, Paint paint, 379 int saveFlags) { 380 return native_saveLayer(mNativeCanvas, left, top, right, bottom, 381 paint != null ? paint.mNativePaint : 0, 382 saveFlags); 383 } 384 385 /** 386 * Convenience for saveLayer(left, top, right, bottom, paint, {@link #ALL_SAVE_FLAG}) 387 */ 388 public int saveLayer(float left, float top, float right, float bottom, Paint paint) { 389 return saveLayer(left, top, right, bottom, paint, ALL_SAVE_FLAG); 390 } 391 392 /** 393 * This behaves the same as save(), but in addition it allocates an 394 * offscreen bitmap. All drawing calls are directed there, and only when 395 * the balancing call to restore() is made is that offscreen transfered to 396 * the canvas (or the previous layer). Subsequent calls to translate, 397 * scale, rotate, skew, concat or clipRect, clipPath all operate on this 398 * copy. When the balancing call to restore() is made, this copy is 399 * deleted and the previous matrix/clip state is restored. 400 * 401 * @param bounds The maximum size the offscreen bitmap needs to be 402 * (in local coordinates) 403 * @param alpha The alpha to apply to the offscreen when when it is 404 drawn during restore() 405 * @param saveFlags see _SAVE_FLAG constants 406 * @return value to pass to restoreToCount() to balance this call 407 */ 408 public int saveLayerAlpha(RectF bounds, int alpha, int saveFlags) { 409 alpha = Math.min(255, Math.max(0, alpha)); 410 return native_saveLayerAlpha(mNativeCanvas, bounds, alpha, saveFlags); 411 } 412 413 /** 414 * Convenience for saveLayerAlpha(bounds, alpha, {@link #ALL_SAVE_FLAG}) 415 */ 416 public int saveLayerAlpha(RectF bounds, int alpha) { 417 return saveLayerAlpha(bounds, alpha, ALL_SAVE_FLAG); 418 } 419 420 /** 421 * Helper for saveLayerAlpha() that takes 4 values instead of a RectF. 422 */ 423 public int saveLayerAlpha(float left, float top, float right, float bottom, int alpha, 424 int saveFlags) { 425 return native_saveLayerAlpha(mNativeCanvas, left, top, right, bottom, 426 alpha, saveFlags); 427 } 428 429 /** 430 * Helper for saveLayerAlpha(left, top, right, bottom, alpha, {@link #ALL_SAVE_FLAG}) 431 */ 432 public int saveLayerAlpha(float left, float top, float right, float bottom, int alpha) { 433 return saveLayerAlpha(left, top, right, bottom, alpha, ALL_SAVE_FLAG); 434 } 435 436 /** 437 * This call balances a previous call to save(), and is used to remove all 438 * modifications to the matrix/clip state since the last save call. It is 439 * an error to call restore() more times than save() was called. 440 */ 441 public native void restore(); 442 443 /** 444 * Returns the number of matrix/clip states on the Canvas' private stack. 445 * This will equal # save() calls - # restore() calls. 446 */ 447 public native int getSaveCount(); 448 449 /** 450 * Efficient way to pop any calls to save() that happened after the save 451 * count reached saveCount. It is an error for saveCount to be less than 1. 452 * 453 * Example: 454 * int count = canvas.save(); 455 * ... // more calls potentially to save() 456 * canvas.restoreToCount(count); 457 * // now the canvas is back in the same state it was before the initial 458 * // call to save(). 459 * 460 * @param saveCount The save level to restore to. 461 */ 462 public native void restoreToCount(int saveCount); 463 464 /** 465 * Preconcat the current matrix with the specified translation 466 * 467 * @param dx The distance to translate in X 468 * @param dy The distance to translate in Y 469 */ 470 public native void translate(float dx, float dy); 471 472 /** 473 * Preconcat the current matrix with the specified scale. 474 * 475 * @param sx The amount to scale in X 476 * @param sy The amount to scale in Y 477 */ 478 public native void scale(float sx, float sy); 479 480 /** 481 * Preconcat the current matrix with the specified scale. 482 * 483 * @param sx The amount to scale in X 484 * @param sy The amount to scale in Y 485 * @param px The x-coord for the pivot point (unchanged by the scale) 486 * @param py The y-coord for the pivot point (unchanged by the scale) 487 */ 488 public final void scale(float sx, float sy, float px, float py) { 489 translate(px, py); 490 scale(sx, sy); 491 translate(-px, -py); 492 } 493 494 /** 495 * Preconcat the current matrix with the specified rotation. 496 * 497 * @param degrees The amount to rotate, in degrees 498 */ 499 public native void rotate(float degrees); 500 501 /** 502 * Preconcat the current matrix with the specified rotation. 503 * 504 * @param degrees The amount to rotate, in degrees 505 * @param px The x-coord for the pivot point (unchanged by the rotation) 506 * @param py The y-coord for the pivot point (unchanged by the rotation) 507 */ 508 public final void rotate(float degrees, float px, float py) { 509 translate(px, py); 510 rotate(degrees); 511 translate(-px, -py); 512 } 513 514 /** 515 * Preconcat the current matrix with the specified skew. 516 * 517 * @param sx The amount to skew in X 518 * @param sy The amount to skew in Y 519 */ 520 public native void skew(float sx, float sy); 521 522 /** 523 * Preconcat the current matrix with the specified matrix. If the specified 524 * matrix is null, this method does nothing. 525 * 526 * @param matrix The matrix to preconcatenate with the current matrix 527 */ 528 public void concat(Matrix matrix) { 529 if (matrix != null) native_concat(mNativeCanvas, matrix.native_instance); 530 } 531 532 /** 533 * Completely replace the current matrix with the specified matrix. If the 534 * matrix parameter is null, then the current matrix is reset to identity. 535 * 536 * <strong>Note:</strong> it is recommended to use {@link #concat(Matrix)}, 537 * {@link #scale(float, float)}, {@link #translate(float, float)} and 538 * {@link #rotate(float)} instead of this method. 539 * 540 * @param matrix The matrix to replace the current matrix with. If it is 541 * null, set the current matrix to identity. 542 * 543 * @see #concat(Matrix) 544 */ 545 public void setMatrix(Matrix matrix) { 546 native_setMatrix(mNativeCanvas, 547 matrix == null ? 0 : matrix.native_instance); 548 } 549 550 /** 551 * Return, in ctm, the current transformation matrix. This does not alter 552 * the matrix in the canvas, but just returns a copy of it. 553 */ 554 @Deprecated 555 public void getMatrix(Matrix ctm) { 556 native_getCTM(mNativeCanvas, ctm.native_instance); 557 } 558 559 /** 560 * Return a new matrix with a copy of the canvas' current transformation 561 * matrix. 562 */ 563 @Deprecated 564 public final Matrix getMatrix() { 565 Matrix m = new Matrix(); 566 //noinspection deprecation 567 getMatrix(m); 568 return m; 569 } 570 571 /** 572 * Modify the current clip with the specified rectangle. 573 * 574 * @param rect The rect to intersect with the current clip 575 * @param op How the clip is modified 576 * @return true if the resulting clip is non-empty 577 */ 578 public boolean clipRect(RectF rect, Region.Op op) { 579 return native_clipRect(mNativeCanvas, rect.left, rect.top, rect.right, rect.bottom, 580 op.nativeInt); 581 } 582 583 /** 584 * Modify the current clip with the specified rectangle, which is 585 * expressed in local coordinates. 586 * 587 * @param rect The rectangle to intersect with the current clip. 588 * @param op How the clip is modified 589 * @return true if the resulting clip is non-empty 590 */ 591 public boolean clipRect(Rect rect, Region.Op op) { 592 return native_clipRect(mNativeCanvas, rect.left, rect.top, rect.right, rect.bottom, 593 op.nativeInt); 594 } 595 596 /** 597 * Intersect the current clip with the specified rectangle, which is 598 * expressed in local coordinates. 599 * 600 * @param rect The rectangle to intersect with the current clip. 601 * @return true if the resulting clip is non-empty 602 */ 603 public native boolean clipRect(RectF rect); 604 605 /** 606 * Intersect the current clip with the specified rectangle, which is 607 * expressed in local coordinates. 608 * 609 * @param rect The rectangle to intersect with the current clip. 610 * @return true if the resulting clip is non-empty 611 */ 612 public native boolean clipRect(Rect rect); 613 614 /** 615 * Modify the current clip with the specified rectangle, which is 616 * expressed in local coordinates. 617 * 618 * @param left The left side of the rectangle to intersect with the 619 * current clip 620 * @param top The top of the rectangle to intersect with the current 621 * clip 622 * @param right The right side of the rectangle to intersect with the 623 * current clip 624 * @param bottom The bottom of the rectangle to intersect with the current 625 * clip 626 * @param op How the clip is modified 627 * @return true if the resulting clip is non-empty 628 */ 629 public boolean clipRect(float left, float top, float right, float bottom, Region.Op op) { 630 return native_clipRect(mNativeCanvas, left, top, right, bottom, op.nativeInt); 631 } 632 633 /** 634 * Intersect the current clip with the specified rectangle, which is 635 * expressed in local coordinates. 636 * 637 * @param left The left side of the rectangle to intersect with the 638 * current clip 639 * @param top The top of the rectangle to intersect with the current clip 640 * @param right The right side of the rectangle to intersect with the 641 * current clip 642 * @param bottom The bottom of the rectangle to intersect with the current 643 * clip 644 * @return true if the resulting clip is non-empty 645 */ 646 public native boolean clipRect(float left, float top, float right, float bottom); 647 648 /** 649 * Intersect the current clip with the specified rectangle, which is 650 * expressed in local coordinates. 651 * 652 * @param left The left side of the rectangle to intersect with the 653 * current clip 654 * @param top The top of the rectangle to intersect with the current clip 655 * @param right The right side of the rectangle to intersect with the 656 * current clip 657 * @param bottom The bottom of the rectangle to intersect with the current 658 * clip 659 * @return true if the resulting clip is non-empty 660 */ 661 public native boolean clipRect(int left, int top, int right, int bottom); 662 663 /** 664 * Modify the current clip with the specified path. 665 * 666 * @param path The path to operate on the current clip 667 * @param op How the clip is modified 668 * @return true if the resulting is non-empty 669 */ 670 public boolean clipPath(Path path, Region.Op op) { 671 return native_clipPath(mNativeCanvas, path.ni(), op.nativeInt); 672 } 673 674 /** 675 * Intersect the current clip with the specified path. 676 * 677 * @param path The path to intersect with the current clip 678 * @return true if the resulting is non-empty 679 */ 680 public boolean clipPath(Path path) { 681 return clipPath(path, Region.Op.INTERSECT); 682 } 683 684 /** 685 * Modify the current clip with the specified region. Note that unlike 686 * clipRect() and clipPath() which transform their arguments by the 687 * current matrix, clipRegion() assumes its argument is already in the 688 * coordinate system of the current layer's bitmap, and so not 689 * transformation is performed. 690 * 691 * @param region The region to operate on the current clip, based on op 692 * @param op How the clip is modified 693 * @return true if the resulting is non-empty 694 */ 695 public boolean clipRegion(Region region, Region.Op op) { 696 return native_clipRegion(mNativeCanvas, region.ni(), op.nativeInt); 697 } 698 699 /** 700 * Intersect the current clip with the specified region. Note that unlike 701 * clipRect() and clipPath() which transform their arguments by the 702 * current matrix, clipRegion() assumes its argument is already in the 703 * coordinate system of the current layer's bitmap, and so not 704 * transformation is performed. 705 * 706 * @param region The region to operate on the current clip, based on op 707 * @return true if the resulting is non-empty 708 */ 709 public boolean clipRegion(Region region) { 710 return clipRegion(region, Region.Op.INTERSECT); 711 } 712 713 public DrawFilter getDrawFilter() { 714 return mDrawFilter; 715 } 716 717 public void setDrawFilter(DrawFilter filter) { 718 long nativeFilter = 0; 719 if (filter != null) { 720 nativeFilter = filter.mNativeInt; 721 } 722 mDrawFilter = filter; 723 nativeSetDrawFilter(mNativeCanvas, nativeFilter); 724 } 725 726 public enum EdgeType { 727 728 /** 729 * Black-and-White: Treat edges by just rounding to nearest pixel boundary 730 */ 731 BW(0), //!< treat edges by just rounding to nearest pixel boundary 732 733 /** 734 * Antialiased: Treat edges by rounding-out, since they may be antialiased 735 */ 736 AA(1); 737 738 EdgeType(int nativeInt) { 739 this.nativeInt = nativeInt; 740 } 741 742 /** 743 * @hide 744 */ 745 public final int nativeInt; 746 } 747 748 /** 749 * Return true if the specified rectangle, after being transformed by the 750 * current matrix, would lie completely outside of the current clip. Call 751 * this to check if an area you intend to draw into is clipped out (and 752 * therefore you can skip making the draw calls). 753 * 754 * @param rect the rect to compare with the current clip 755 * @param type {@link Canvas.EdgeType#AA} if the path should be considered antialiased, 756 * since that means it may affect a larger area (more pixels) than 757 * non-antialiased ({@link Canvas.EdgeType#BW}). 758 * @return true if the rect (transformed by the canvas' matrix) 759 * does not intersect with the canvas' clip 760 */ 761 public boolean quickReject(RectF rect, EdgeType type) { 762 return native_quickReject(mNativeCanvas, rect); 763 } 764 765 /** 766 * Return true if the specified path, after being transformed by the 767 * current matrix, would lie completely outside of the current clip. Call 768 * this to check if an area you intend to draw into is clipped out (and 769 * therefore you can skip making the draw calls). Note: for speed it may 770 * return false even if the path itself might not intersect the clip 771 * (i.e. the bounds of the path intersects, but the path does not). 772 * 773 * @param path The path to compare with the current clip 774 * @param type {@link Canvas.EdgeType#AA} if the path should be considered antialiased, 775 * since that means it may affect a larger area (more pixels) than 776 * non-antialiased ({@link Canvas.EdgeType#BW}). 777 * @return true if the path (transformed by the canvas' matrix) 778 * does not intersect with the canvas' clip 779 */ 780 public boolean quickReject(Path path, EdgeType type) { 781 return native_quickReject(mNativeCanvas, path.ni()); 782 } 783 784 /** 785 * Return true if the specified rectangle, after being transformed by the 786 * current matrix, would lie completely outside of the current clip. Call 787 * this to check if an area you intend to draw into is clipped out (and 788 * therefore you can skip making the draw calls). 789 * 790 * @param left The left side of the rectangle to compare with the 791 * current clip 792 * @param top The top of the rectangle to compare with the current 793 * clip 794 * @param right The right side of the rectangle to compare with the 795 * current clip 796 * @param bottom The bottom of the rectangle to compare with the 797 * current clip 798 * @param type {@link Canvas.EdgeType#AA} if the path should be considered antialiased, 799 * since that means it may affect a larger area (more pixels) than 800 * non-antialiased ({@link Canvas.EdgeType#BW}). 801 * @return true if the rect (transformed by the canvas' matrix) 802 * does not intersect with the canvas' clip 803 */ 804 public boolean quickReject(float left, float top, float right, float bottom, 805 EdgeType type) { 806 return native_quickReject(mNativeCanvas, left, top, right, bottom); 807 } 808 809 /** 810 * Return the bounds of the current clip (in local coordinates) in the 811 * bounds parameter, and return true if it is non-empty. This can be useful 812 * in a way similar to quickReject, in that it tells you that drawing 813 * outside of these bounds will be clipped out. 814 * 815 * @param bounds Return the clip bounds here. If it is null, ignore it but 816 * still return true if the current clip is non-empty. 817 * @return true if the current clip is non-empty. 818 */ 819 public boolean getClipBounds(Rect bounds) { 820 return native_getClipBounds(mNativeCanvas, bounds); 821 } 822 823 /** 824 * Retrieve the bounds of the current clip (in local coordinates). 825 * 826 * @return the clip bounds, or [0, 0, 0, 0] if the clip is empty. 827 */ 828 public final Rect getClipBounds() { 829 Rect r = new Rect(); 830 getClipBounds(r); 831 return r; 832 } 833 834 /** 835 * Fill the entire canvas' bitmap (restricted to the current clip) with the 836 * specified RGB color, using srcover porterduff mode. 837 * 838 * @param r red component (0..255) of the color to draw onto the canvas 839 * @param g green component (0..255) of the color to draw onto the canvas 840 * @param b blue component (0..255) of the color to draw onto the canvas 841 */ 842 public void drawRGB(int r, int g, int b) { 843 native_drawRGB(mNativeCanvas, r, g, b); 844 } 845 846 /** 847 * Fill the entire canvas' bitmap (restricted to the current clip) with the 848 * specified ARGB color, using srcover porterduff mode. 849 * 850 * @param a alpha component (0..255) of the color to draw onto the canvas 851 * @param r red component (0..255) of the color to draw onto the canvas 852 * @param g green component (0..255) of the color to draw onto the canvas 853 * @param b blue component (0..255) of the color to draw onto the canvas 854 */ 855 public void drawARGB(int a, int r, int g, int b) { 856 native_drawARGB(mNativeCanvas, a, r, g, b); 857 } 858 859 /** 860 * Fill the entire canvas' bitmap (restricted to the current clip) with the 861 * specified color, using srcover porterduff mode. 862 * 863 * @param color the color to draw onto the canvas 864 */ 865 public void drawColor(int color) { 866 native_drawColor(mNativeCanvas, color); 867 } 868 869 /** 870 * Fill the entire canvas' bitmap (restricted to the current clip) with the 871 * specified color and porter-duff xfermode. 872 * 873 * @param color the color to draw with 874 * @param mode the porter-duff mode to apply to the color 875 */ 876 public void drawColor(int color, PorterDuff.Mode mode) { 877 native_drawColor(mNativeCanvas, color, mode.nativeInt); 878 } 879 880 /** 881 * Fill the entire canvas' bitmap (restricted to the current clip) with 882 * the specified paint. This is equivalent (but faster) to drawing an 883 * infinitely large rectangle with the specified paint. 884 * 885 * @param paint The paint used to draw onto the canvas 886 */ 887 public void drawPaint(Paint paint) { 888 native_drawPaint(mNativeCanvas, paint.mNativePaint); 889 } 890 891 /** 892 * Draw a series of points. Each point is centered at the coordinate 893 * specified by pts[], and its diameter is specified by the paint's stroke 894 * width (as transformed by the canvas' CTM), with special treatment for 895 * a stroke width of 0, which always draws exactly 1 pixel (or at most 4 896 * if antialiasing is enabled). The shape of the point is controlled by 897 * the paint's Cap type. The shape is a square, unless the cap type is 898 * Round, in which case the shape is a circle. 899 * 900 * @param pts Array of points to draw [x0 y0 x1 y1 x2 y2 ...] 901 * @param offset Number of values to skip before starting to draw. 902 * @param count The number of values to process, after skipping offset 903 * of them. Since one point uses two values, the number of 904 * "points" that are drawn is really (count >> 1). 905 * @param paint The paint used to draw the points 906 */ 907 public native void drawPoints(float[] pts, int offset, int count, Paint paint); 908 909 /** 910 * Helper for drawPoints() that assumes you want to draw the entire array 911 */ 912 public void drawPoints(float[] pts, Paint paint) { 913 drawPoints(pts, 0, pts.length, paint); 914 } 915 916 /** 917 * Helper for drawPoints() for drawing a single point. 918 */ 919 public native void drawPoint(float x, float y, Paint paint); 920 921 /** 922 * Draw a line segment with the specified start and stop x,y coordinates, 923 * using the specified paint. 924 * 925 * <p>Note that since a line is always "framed", the Style is ignored in the paint.</p> 926 * 927 * <p>Degenerate lines (length is 0) will not be drawn.</p> 928 * 929 * @param startX The x-coordinate of the start point of the line 930 * @param startY The y-coordinate of the start point of the line 931 * @param paint The paint used to draw the line 932 */ 933 public void drawLine(float startX, float startY, float stopX, float stopY, Paint paint) { 934 native_drawLine(mNativeCanvas, startX, startY, stopX, stopY, paint.mNativePaint); 935 } 936 937 /** 938 * Draw a series of lines. Each line is taken from 4 consecutive values 939 * in the pts array. Thus to draw 1 line, the array must contain at least 4 940 * values. This is logically the same as drawing the array as follows: 941 * drawLine(pts[0], pts[1], pts[2], pts[3]) followed by 942 * drawLine(pts[4], pts[5], pts[6], pts[7]) and so on. 943 * 944 * @param pts Array of points to draw [x0 y0 x1 y1 x2 y2 ...] 945 * @param offset Number of values in the array to skip before drawing. 946 * @param count The number of values in the array to process, after 947 * skipping "offset" of them. Since each line uses 4 values, 948 * the number of "lines" that are drawn is really 949 * (count >> 2). 950 * @param paint The paint used to draw the points 951 */ 952 public native void drawLines(float[] pts, int offset, int count, Paint paint); 953 954 public void drawLines(float[] pts, Paint paint) { 955 drawLines(pts, 0, pts.length, paint); 956 } 957 958 /** 959 * Draw the specified Rect using the specified paint. The rectangle will 960 * be filled or framed based on the Style in the paint. 961 * 962 * @param rect The rect to be drawn 963 * @param paint The paint used to draw the rect 964 */ 965 public void drawRect(RectF rect, Paint paint) { 966 native_drawRect(mNativeCanvas, rect, paint.mNativePaint); 967 } 968 969 /** 970 * Draw the specified Rect using the specified Paint. The rectangle 971 * will be filled or framed based on the Style in the paint. 972 * 973 * @param r The rectangle to be drawn. 974 * @param paint The paint used to draw the rectangle 975 */ 976 public void drawRect(Rect r, Paint paint) { 977 drawRect(r.left, r.top, r.right, r.bottom, paint); 978 } 979 980 981 /** 982 * Draw the specified Rect using the specified paint. The rectangle will 983 * be filled or framed based on the Style in the paint. 984 * 985 * @param left The left side of the rectangle to be drawn 986 * @param top The top side of the rectangle to be drawn 987 * @param right The right side of the rectangle to be drawn 988 * @param bottom The bottom side of the rectangle to be drawn 989 * @param paint The paint used to draw the rect 990 */ 991 public void drawRect(float left, float top, float right, float bottom, Paint paint) { 992 native_drawRect(mNativeCanvas, left, top, right, bottom, paint.mNativePaint); 993 } 994 995 /** 996 * Draw the specified oval using the specified paint. The oval will be 997 * filled or framed based on the Style in the paint. 998 * 999 * @param oval The rectangle bounds of the oval to be drawn 1000 */ 1001 public void drawOval(RectF oval, Paint paint) { 1002 if (oval == null) { 1003 throw new NullPointerException(); 1004 } 1005 native_drawOval(mNativeCanvas, oval, paint.mNativePaint); 1006 } 1007 1008 /** 1009 * Draw the specified circle using the specified paint. If radius is <= 0, 1010 * then nothing will be drawn. The circle will be filled or framed based 1011 * on the Style in the paint. 1012 * 1013 * @param cx The x-coordinate of the center of the cirle to be drawn 1014 * @param cy The y-coordinate of the center of the cirle to be drawn 1015 * @param radius The radius of the cirle to be drawn 1016 * @param paint The paint used to draw the circle 1017 */ 1018 public void drawCircle(float cx, float cy, float radius, Paint paint) { 1019 native_drawCircle(mNativeCanvas, cx, cy, radius, paint.mNativePaint); 1020 } 1021 1022 /** 1023 * <p>Draw the specified arc, which will be scaled to fit inside the 1024 * specified oval.</p> 1025 * 1026 * <p>If the start angle is negative or >= 360, the start angle is treated 1027 * as start angle modulo 360.</p> 1028 * 1029 * <p>If the sweep angle is >= 360, then the oval is drawn 1030 * completely. Note that this differs slightly from SkPath::arcTo, which 1031 * treats the sweep angle modulo 360. If the sweep angle is negative, 1032 * the sweep angle is treated as sweep angle modulo 360</p> 1033 * 1034 * <p>The arc is drawn clockwise. An angle of 0 degrees correspond to the 1035 * geometric angle of 0 degrees (3 o'clock on a watch.)</p> 1036 * 1037 * @param oval The bounds of oval used to define the shape and size 1038 * of the arc 1039 * @param startAngle Starting angle (in degrees) where the arc begins 1040 * @param sweepAngle Sweep angle (in degrees) measured clockwise 1041 * @param useCenter If true, include the center of the oval in the arc, and 1042 close it if it is being stroked. This will draw a wedge 1043 * @param paint The paint used to draw the arc 1044 */ 1045 public void drawArc(RectF oval, float startAngle, float sweepAngle, boolean useCenter, 1046 Paint paint) { 1047 if (oval == null) { 1048 throw new NullPointerException(); 1049 } 1050 native_drawArc(mNativeCanvas, oval, startAngle, sweepAngle, 1051 useCenter, paint.mNativePaint); 1052 } 1053 1054 /** 1055 * Draw the specified round-rect using the specified paint. The roundrect 1056 * will be filled or framed based on the Style in the paint. 1057 * 1058 * @param rect The rectangular bounds of the roundRect to be drawn 1059 * @param rx The x-radius of the oval used to round the corners 1060 * @param ry The y-radius of the oval used to round the corners 1061 * @param paint The paint used to draw the roundRect 1062 */ 1063 public void drawRoundRect(RectF rect, float rx, float ry, Paint paint) { 1064 if (rect == null) { 1065 throw new NullPointerException(); 1066 } 1067 native_drawRoundRect(mNativeCanvas, rect, rx, ry, 1068 paint.mNativePaint); 1069 } 1070 1071 /** 1072 * Draw the specified path using the specified paint. The path will be 1073 * filled or framed based on the Style in the paint. 1074 * 1075 * @param path The path to be drawn 1076 * @param paint The paint used to draw the path 1077 */ 1078 public void drawPath(Path path, Paint paint) { 1079 native_drawPath(mNativeCanvas, path.ni(), paint.mNativePaint); 1080 } 1081 1082 /** 1083 * @hide 1084 */ 1085 protected static void throwIfCannotDraw(Bitmap bitmap) { 1086 if (bitmap.isRecycled()) { 1087 throw new RuntimeException("Canvas: trying to use a recycled bitmap " + bitmap); 1088 } 1089 if (!bitmap.isPremultiplied() && bitmap.getConfig() == Bitmap.Config.ARGB_8888 && 1090 bitmap.hasAlpha()) { 1091 throw new RuntimeException("Canvas: trying to use a non-premultiplied bitmap " 1092 + bitmap); 1093 } 1094 } 1095 1096 /** 1097 * Draws the specified bitmap as an N-patch (most often, a 9-patches.) 1098 * 1099 * @param patch The ninepatch object to render 1100 * @param dst The destination rectangle. 1101 * @param paint The paint to draw the bitmap with. may be null 1102 * 1103 * @hide 1104 */ 1105 public void drawPatch(NinePatch patch, Rect dst, Paint paint) { 1106 patch.drawSoftware(this, dst, paint); 1107 } 1108 1109 /** 1110 * Draws the specified bitmap as an N-patch (most often, a 9-patches.) 1111 * 1112 * @param patch The ninepatch object to render 1113 * @param dst The destination rectangle. 1114 * @param paint The paint to draw the bitmap with. may be null 1115 * 1116 * @hide 1117 */ 1118 public void drawPatch(NinePatch patch, RectF dst, Paint paint) { 1119 patch.drawSoftware(this, dst, paint); 1120 } 1121 1122 /** 1123 * Draw the specified bitmap, with its top/left corner at (x,y), using 1124 * the specified paint, transformed by the current matrix. 1125 * 1126 * <p>Note: if the paint contains a maskfilter that generates a mask which 1127 * extends beyond the bitmap's original width/height (e.g. BlurMaskFilter), 1128 * then the bitmap will be drawn as if it were in a Shader with CLAMP mode. 1129 * Thus the color outside of the original width/height will be the edge 1130 * color replicated. 1131 * 1132 * <p>If the bitmap and canvas have different densities, this function 1133 * will take care of automatically scaling the bitmap to draw at the 1134 * same density as the canvas. 1135 * 1136 * @param bitmap The bitmap to be drawn 1137 * @param left The position of the left side of the bitmap being drawn 1138 * @param top The position of the top side of the bitmap being drawn 1139 * @param paint The paint used to draw the bitmap (may be null) 1140 */ 1141 public void drawBitmap(Bitmap bitmap, float left, float top, Paint paint) { 1142 throwIfCannotDraw(bitmap); 1143 native_drawBitmap(mNativeCanvas, bitmap.ni(), left, top, 1144 paint != null ? paint.mNativePaint : 0, mDensity, mScreenDensity, bitmap.mDensity); 1145 } 1146 1147 /** 1148 * Draw the specified bitmap, scaling/translating automatically to fill 1149 * the destination rectangle. If the source rectangle is not null, it 1150 * specifies the subset of the bitmap to draw. 1151 * 1152 * <p>Note: if the paint contains a maskfilter that generates a mask which 1153 * extends beyond the bitmap's original width/height (e.g. BlurMaskFilter), 1154 * then the bitmap will be drawn as if it were in a Shader with CLAMP mode. 1155 * Thus the color outside of the original width/height will be the edge 1156 * color replicated. 1157 * 1158 * <p>This function <em>ignores the density associated with the bitmap</em>. 1159 * This is because the source and destination rectangle coordinate 1160 * spaces are in their respective densities, so must already have the 1161 * appropriate scaling factor applied. 1162 * 1163 * @param bitmap The bitmap to be drawn 1164 * @param src May be null. The subset of the bitmap to be drawn 1165 * @param dst The rectangle that the bitmap will be scaled/translated 1166 * to fit into 1167 * @param paint May be null. The paint used to draw the bitmap 1168 */ 1169 public void drawBitmap(Bitmap bitmap, Rect src, RectF dst, Paint paint) { 1170 if (dst == null) { 1171 throw new NullPointerException(); 1172 } 1173 throwIfCannotDraw(bitmap); 1174 native_drawBitmap(mNativeCanvas, bitmap.ni(), src, dst, 1175 paint != null ? paint.mNativePaint : 0, mScreenDensity, bitmap.mDensity); 1176 } 1177 1178 /** 1179 * Draw the specified bitmap, scaling/translating automatically to fill 1180 * the destination rectangle. If the source rectangle is not null, it 1181 * specifies the subset of the bitmap to draw. 1182 * 1183 * <p>Note: if the paint contains a maskfilter that generates a mask which 1184 * extends beyond the bitmap's original width/height (e.g. BlurMaskFilter), 1185 * then the bitmap will be drawn as if it were in a Shader with CLAMP mode. 1186 * Thus the color outside of the original width/height will be the edge 1187 * color replicated. 1188 * 1189 * <p>This function <em>ignores the density associated with the bitmap</em>. 1190 * This is because the source and destination rectangle coordinate 1191 * spaces are in their respective densities, so must already have the 1192 * appropriate scaling factor applied. 1193 * 1194 * @param bitmap The bitmap to be drawn 1195 * @param src May be null. The subset of the bitmap to be drawn 1196 * @param dst The rectangle that the bitmap will be scaled/translated 1197 * to fit into 1198 * @param paint May be null. The paint used to draw the bitmap 1199 */ 1200 public void drawBitmap(Bitmap bitmap, Rect src, Rect dst, Paint paint) { 1201 if (dst == null) { 1202 throw new NullPointerException(); 1203 } 1204 throwIfCannotDraw(bitmap); 1205 native_drawBitmap(mNativeCanvas, bitmap.ni(), src, dst, 1206 paint != null ? paint.mNativePaint : 0, mScreenDensity, bitmap.mDensity); 1207 } 1208 1209 /** 1210 * Treat the specified array of colors as a bitmap, and draw it. This gives 1211 * the same result as first creating a bitmap from the array, and then 1212 * drawing it, but this method avoids explicitly creating a bitmap object 1213 * which can be more efficient if the colors are changing often. 1214 * 1215 * @param colors Array of colors representing the pixels of the bitmap 1216 * @param offset Offset into the array of colors for the first pixel 1217 * @param stride The number of colors in the array between rows (must be 1218 * >= width or <= -width). 1219 * @param x The X coordinate for where to draw the bitmap 1220 * @param y The Y coordinate for where to draw the bitmap 1221 * @param width The width of the bitmap 1222 * @param height The height of the bitmap 1223 * @param hasAlpha True if the alpha channel of the colors contains valid 1224 * values. If false, the alpha byte is ignored (assumed to 1225 * be 0xFF for every pixel). 1226 * @param paint May be null. The paint used to draw the bitmap 1227 * 1228 * @deprecated Usage with a {@link #isHardwareAccelerated() hardware accelerated} canvas 1229 * requires an internal copy of color buffer contents every time this method is called. Using a 1230 * Bitmap avoids this copy, and allows the application to more explicitly control the lifetime 1231 * and copies of pixel data. 1232 */ 1233 @Deprecated 1234 public void drawBitmap(int[] colors, int offset, int stride, float x, float y, 1235 int width, int height, boolean hasAlpha, Paint paint) { 1236 // check for valid input 1237 if (width < 0) { 1238 throw new IllegalArgumentException("width must be >= 0"); 1239 } 1240 if (height < 0) { 1241 throw new IllegalArgumentException("height must be >= 0"); 1242 } 1243 if (Math.abs(stride) < width) { 1244 throw new IllegalArgumentException("abs(stride) must be >= width"); 1245 } 1246 int lastScanline = offset + (height - 1) * stride; 1247 int length = colors.length; 1248 if (offset < 0 || (offset + width > length) || lastScanline < 0 1249 || (lastScanline + width > length)) { 1250 throw new ArrayIndexOutOfBoundsException(); 1251 } 1252 // quick escape if there's nothing to draw 1253 if (width == 0 || height == 0) { 1254 return; 1255 } 1256 // punch down to native for the actual draw 1257 native_drawBitmap(mNativeCanvas, colors, offset, stride, x, y, width, height, hasAlpha, 1258 paint != null ? paint.mNativePaint : 0); 1259 } 1260 1261 /** 1262 * Legacy version of drawBitmap(int[] colors, ...) that took ints for x,y 1263 * 1264 * @deprecated Usage with a {@link #isHardwareAccelerated() hardware accelerated} canvas 1265 * requires an internal copy of color buffer contents every time this method is called. Using a 1266 * Bitmap avoids this copy, and allows the application to more explicitly control the lifetime 1267 * and copies of pixel data. 1268 */ 1269 @Deprecated 1270 public void drawBitmap(int[] colors, int offset, int stride, int x, int y, 1271 int width, int height, boolean hasAlpha, Paint paint) { 1272 // call through to the common float version 1273 drawBitmap(colors, offset, stride, (float)x, (float)y, width, height, 1274 hasAlpha, paint); 1275 } 1276 1277 /** 1278 * Draw the bitmap using the specified matrix. 1279 * 1280 * @param bitmap The bitmap to draw 1281 * @param matrix The matrix used to transform the bitmap when it is drawn 1282 * @param paint May be null. The paint used to draw the bitmap 1283 */ 1284 public void drawBitmap(Bitmap bitmap, Matrix matrix, Paint paint) { 1285 nativeDrawBitmapMatrix(mNativeCanvas, bitmap.ni(), matrix.ni(), 1286 paint != null ? paint.mNativePaint : 0); 1287 } 1288 1289 /** 1290 * @hide 1291 */ 1292 protected static void checkRange(int length, int offset, int count) { 1293 if ((offset | count) < 0 || offset + count > length) { 1294 throw new ArrayIndexOutOfBoundsException(); 1295 } 1296 } 1297 1298 /** 1299 * Draw the bitmap through the mesh, where mesh vertices are evenly 1300 * distributed across the bitmap. There are meshWidth+1 vertices across, and 1301 * meshHeight+1 vertices down. The verts array is accessed in row-major 1302 * order, so that the first meshWidth+1 vertices are distributed across the 1303 * top of the bitmap from left to right. A more general version of this 1304 * method is drawVertices(). 1305 * 1306 * @param bitmap The bitmap to draw using the mesh 1307 * @param meshWidth The number of columns in the mesh. Nothing is drawn if 1308 * this is 0 1309 * @param meshHeight The number of rows in the mesh. Nothing is drawn if 1310 * this is 0 1311 * @param verts Array of x,y pairs, specifying where the mesh should be 1312 * drawn. There must be at least 1313 * (meshWidth+1) * (meshHeight+1) * 2 + vertOffset values 1314 * in the array 1315 * @param vertOffset Number of verts elements to skip before drawing 1316 * @param colors May be null. Specifies a color at each vertex, which is 1317 * interpolated across the cell, and whose values are 1318 * multiplied by the corresponding bitmap colors. If not null, 1319 * there must be at least (meshWidth+1) * (meshHeight+1) + 1320 * colorOffset values in the array. 1321 * @param colorOffset Number of color elements to skip before drawing 1322 * @param paint May be null. The paint used to draw the bitmap 1323 */ 1324 public void drawBitmapMesh(Bitmap bitmap, int meshWidth, int meshHeight, 1325 float[] verts, int vertOffset, int[] colors, int colorOffset, Paint paint) { 1326 if ((meshWidth | meshHeight | vertOffset | colorOffset) < 0) { 1327 throw new ArrayIndexOutOfBoundsException(); 1328 } 1329 if (meshWidth == 0 || meshHeight == 0) { 1330 return; 1331 } 1332 int count = (meshWidth + 1) * (meshHeight + 1); 1333 // we mul by 2 since we need two floats per vertex 1334 checkRange(verts.length, vertOffset, count * 2); 1335 if (colors != null) { 1336 // no mul by 2, since we need only 1 color per vertex 1337 checkRange(colors.length, colorOffset, count); 1338 } 1339 nativeDrawBitmapMesh(mNativeCanvas, bitmap.ni(), meshWidth, meshHeight, 1340 verts, vertOffset, colors, colorOffset, 1341 paint != null ? paint.mNativePaint : 0); 1342 } 1343 1344 public enum VertexMode { 1345 TRIANGLES(0), 1346 TRIANGLE_STRIP(1), 1347 TRIANGLE_FAN(2); 1348 1349 VertexMode(int nativeInt) { 1350 this.nativeInt = nativeInt; 1351 } 1352 1353 /** 1354 * @hide 1355 */ 1356 public final int nativeInt; 1357 } 1358 1359 /** 1360 * Draw the array of vertices, interpreted as triangles (based on mode). The 1361 * verts array is required, and specifies the x,y pairs for each vertex. If 1362 * texs is non-null, then it is used to specify the coordinate in shader 1363 * coordinates to use at each vertex (the paint must have a shader in this 1364 * case). If there is no texs array, but there is a color array, then each 1365 * color is interpolated across its corresponding triangle in a gradient. If 1366 * both texs and colors arrays are present, then they behave as before, but 1367 * the resulting color at each pixels is the result of multiplying the 1368 * colors from the shader and the color-gradient together. The indices array 1369 * is optional, but if it is present, then it is used to specify the index 1370 * of each triangle, rather than just walking through the arrays in order. 1371 * 1372 * @param mode How to interpret the array of vertices 1373 * @param vertexCount The number of values in the vertices array (and 1374 * corresponding texs and colors arrays if non-null). Each logical 1375 * vertex is two values (x, y), vertexCount must be a multiple of 2. 1376 * @param verts Array of vertices for the mesh 1377 * @param vertOffset Number of values in the verts to skip before drawing. 1378 * @param texs May be null. If not null, specifies the coordinates to sample 1379 * into the current shader (e.g. bitmap tile or gradient) 1380 * @param texOffset Number of values in texs to skip before drawing. 1381 * @param colors May be null. If not null, specifies a color for each 1382 * vertex, to be interpolated across the triangle. 1383 * @param colorOffset Number of values in colors to skip before drawing. 1384 * @param indices If not null, array of indices to reference into the 1385 * vertex (texs, colors) array. 1386 * @param indexCount number of entries in the indices array (if not null). 1387 * @param paint Specifies the shader to use if the texs array is non-null. 1388 */ 1389 public void drawVertices(VertexMode mode, int vertexCount, float[] verts, int vertOffset, 1390 float[] texs, int texOffset, int[] colors, int colorOffset, 1391 short[] indices, int indexOffset, int indexCount, Paint paint) { 1392 checkRange(verts.length, vertOffset, vertexCount); 1393 if (texs != null) { 1394 checkRange(texs.length, texOffset, vertexCount); 1395 } 1396 if (colors != null) { 1397 checkRange(colors.length, colorOffset, vertexCount / 2); 1398 } 1399 if (indices != null) { 1400 checkRange(indices.length, indexOffset, indexCount); 1401 } 1402 nativeDrawVertices(mNativeCanvas, mode.nativeInt, vertexCount, verts, 1403 vertOffset, texs, texOffset, colors, colorOffset, 1404 indices, indexOffset, indexCount, paint.mNativePaint); 1405 } 1406 1407 /** 1408 * Draw the text, with origin at (x,y), using the specified paint. The 1409 * origin is interpreted based on the Align setting in the paint. 1410 * 1411 * @param text The text to be drawn 1412 * @param x The x-coordinate of the origin of the text being drawn 1413 * @param y The y-coordinate of the origin of the text being drawn 1414 * @param paint The paint used for the text (e.g. color, size, style) 1415 */ 1416 public void drawText(char[] text, int index, int count, float x, float y, Paint paint) { 1417 if ((index | count | (index + count) | 1418 (text.length - index - count)) < 0) { 1419 throw new IndexOutOfBoundsException(); 1420 } 1421 native_drawText(mNativeCanvas, text, index, count, x, y, paint.mBidiFlags, 1422 paint.mNativePaint, paint.mNativeTypeface); 1423 } 1424 1425 /** 1426 * Draw the text, with origin at (x,y), using the specified paint. The 1427 * origin is interpreted based on the Align setting in the paint. 1428 * 1429 * @param text The text to be drawn 1430 * @param x The x-coordinate of the origin of the text being drawn 1431 * @param y The y-coordinate of the origin of the text being drawn 1432 * @param paint The paint used for the text (e.g. color, size, style) 1433 */ 1434 public void drawText(String text, float x, float y, Paint paint) { 1435 native_drawText(mNativeCanvas, text, 0, text.length(), x, y, paint.mBidiFlags, 1436 paint.mNativePaint, paint.mNativeTypeface); 1437 } 1438 1439 /** 1440 * Draw the text, with origin at (x,y), using the specified paint. 1441 * The origin is interpreted based on the Align setting in the paint. 1442 * 1443 * @param text The text to be drawn 1444 * @param start The index of the first character in text to draw 1445 * @param end (end - 1) is the index of the last character in text to draw 1446 * @param x The x-coordinate of the origin of the text being drawn 1447 * @param y The y-coordinate of the origin of the text being drawn 1448 * @param paint The paint used for the text (e.g. color, size, style) 1449 */ 1450 public void drawText(String text, int start, int end, float x, float y, Paint paint) { 1451 if ((start | end | (end - start) | (text.length() - end)) < 0) { 1452 throw new IndexOutOfBoundsException(); 1453 } 1454 native_drawText(mNativeCanvas, text, start, end, x, y, paint.mBidiFlags, 1455 paint.mNativePaint, paint.mNativeTypeface); 1456 } 1457 1458 /** 1459 * Draw the specified range of text, specified by start/end, with its 1460 * origin at (x,y), in the specified Paint. The origin is interpreted 1461 * based on the Align setting in the Paint. 1462 * 1463 * @param text The text to be drawn 1464 * @param start The index of the first character in text to draw 1465 * @param end (end - 1) is the index of the last character in text 1466 * to draw 1467 * @param x The x-coordinate of origin for where to draw the text 1468 * @param y The y-coordinate of origin for where to draw the text 1469 * @param paint The paint used for the text (e.g. color, size, style) 1470 */ 1471 public void drawText(CharSequence text, int start, int end, float x, float y, Paint paint) { 1472 if (text instanceof String || text instanceof SpannedString || 1473 text instanceof SpannableString) { 1474 native_drawText(mNativeCanvas, text.toString(), start, end, x, y, 1475 paint.mBidiFlags, paint.mNativePaint, paint.mNativeTypeface); 1476 } else if (text instanceof GraphicsOperations) { 1477 ((GraphicsOperations) text).drawText(this, start, end, x, y, 1478 paint); 1479 } else { 1480 char[] buf = TemporaryBuffer.obtain(end - start); 1481 TextUtils.getChars(text, start, end, buf, 0); 1482 native_drawText(mNativeCanvas, buf, 0, end - start, x, y, 1483 paint.mBidiFlags, paint.mNativePaint, paint.mNativeTypeface); 1484 TemporaryBuffer.recycle(buf); 1485 } 1486 } 1487 1488 /** 1489 * Render a run of all LTR or all RTL text, with shaping. This does not run 1490 * bidi on the provided text, but renders it as a uniform right-to-left or 1491 * left-to-right run, as indicated by dir. Alignment of the text is as 1492 * determined by the Paint's TextAlign value. 1493 * 1494 * @param text the text to render 1495 * @param index the start of the text to render 1496 * @param count the count of chars to render 1497 * @param contextIndex the start of the context for shaping. Must be 1498 * no greater than index. 1499 * @param contextCount the number of characters in the context for shaping. 1500 * ContexIndex + contextCount must be no less than index 1501 * + count. 1502 * @param x the x position at which to draw the text 1503 * @param y the y position at which to draw the text 1504 * @param dir the run direction, either {@link #DIRECTION_LTR} or 1505 * {@link #DIRECTION_RTL}. 1506 * @param paint the paint 1507 * @hide 1508 */ 1509 public void drawTextRun(char[] text, int index, int count, int contextIndex, int contextCount, 1510 float x, float y, int dir, Paint paint) { 1511 1512 if (text == null) { 1513 throw new NullPointerException("text is null"); 1514 } 1515 if (paint == null) { 1516 throw new NullPointerException("paint is null"); 1517 } 1518 if ((index | count | text.length - index - count) < 0) { 1519 throw new IndexOutOfBoundsException(); 1520 } 1521 if (dir != DIRECTION_LTR && dir != DIRECTION_RTL) { 1522 throw new IllegalArgumentException("unknown dir: " + dir); 1523 } 1524 1525 native_drawTextRun(mNativeCanvas, text, index, count, 1526 contextIndex, contextCount, x, y, dir, paint.mNativePaint, paint.mNativeTypeface); 1527 } 1528 1529 /** 1530 * Render a run of all LTR or all RTL text, with shaping. This does not run 1531 * bidi on the provided text, but renders it as a uniform right-to-left or 1532 * left-to-right run, as indicated by dir. Alignment of the text is as 1533 * determined by the Paint's TextAlign value. 1534 * 1535 * @param text the text to render 1536 * @param start the start of the text to render. Data before this position 1537 * can be used for shaping context. 1538 * @param end the end of the text to render. Data at or after this 1539 * position can be used for shaping context. 1540 * @param x the x position at which to draw the text 1541 * @param y the y position at which to draw the text 1542 * @param dir the run direction, either 0 for LTR or 1 for RTL. 1543 * @param paint the paint 1544 * @hide 1545 */ 1546 public void drawTextRun(CharSequence text, int start, int end, int contextStart, int contextEnd, 1547 float x, float y, int dir, Paint paint) { 1548 1549 if (text == null) { 1550 throw new NullPointerException("text is null"); 1551 } 1552 if (paint == null) { 1553 throw new NullPointerException("paint is null"); 1554 } 1555 if ((start | end | end - start | text.length() - end) < 0) { 1556 throw new IndexOutOfBoundsException(); 1557 } 1558 1559 int flags = dir == 0 ? 0 : 1; 1560 1561 if (text instanceof String || text instanceof SpannedString || 1562 text instanceof SpannableString) { 1563 native_drawTextRun(mNativeCanvas, text.toString(), start, end, 1564 contextStart, contextEnd, x, y, flags, paint.mNativePaint, paint.mNativeTypeface); 1565 } else if (text instanceof GraphicsOperations) { 1566 ((GraphicsOperations) text).drawTextRun(this, start, end, 1567 contextStart, contextEnd, x, y, flags, paint); 1568 } else { 1569 int contextLen = contextEnd - contextStart; 1570 int len = end - start; 1571 char[] buf = TemporaryBuffer.obtain(contextLen); 1572 TextUtils.getChars(text, contextStart, contextEnd, buf, 0); 1573 native_drawTextRun(mNativeCanvas, buf, start - contextStart, len, 1574 0, contextLen, x, y, flags, paint.mNativePaint, paint.mNativeTypeface); 1575 TemporaryBuffer.recycle(buf); 1576 } 1577 } 1578 1579 /** 1580 * Draw the text in the array, with each character's origin specified by 1581 * the pos array. 1582 * 1583 * This method does not support glyph composition and decomposition and 1584 * should therefore not be used to render complex scripts. 1585 * 1586 * @param text The text to be drawn 1587 * @param index The index of the first character to draw 1588 * @param count The number of characters to draw, starting from index. 1589 * @param pos Array of [x,y] positions, used to position each 1590 * character 1591 * @param paint The paint used for the text (e.g. color, size, style) 1592 */ 1593 @Deprecated 1594 public void drawPosText(char[] text, int index, int count, float[] pos, Paint paint) { 1595 if (index < 0 || index + count > text.length || count*2 > pos.length) { 1596 throw new IndexOutOfBoundsException(); 1597 } 1598 native_drawPosText(mNativeCanvas, text, index, count, pos, 1599 paint.mNativePaint); 1600 } 1601 1602 /** 1603 * Draw the text in the array, with each character's origin specified by 1604 * the pos array. 1605 * 1606 * This method does not support glyph composition and decomposition and 1607 * should therefore not be used to render complex scripts. 1608 * 1609 * @param text The text to be drawn 1610 * @param pos Array of [x,y] positions, used to position each character 1611 * @param paint The paint used for the text (e.g. color, size, style) 1612 */ 1613 @Deprecated 1614 public void drawPosText(String text, float[] pos, Paint paint) { 1615 if (text.length()*2 > pos.length) { 1616 throw new ArrayIndexOutOfBoundsException(); 1617 } 1618 native_drawPosText(mNativeCanvas, text, pos, paint.mNativePaint); 1619 } 1620 1621 /** 1622 * Draw the text, with origin at (x,y), using the specified paint, along 1623 * the specified path. The paint's Align setting determins where along the 1624 * path to start the text. 1625 * 1626 * @param text The text to be drawn 1627 * @param path The path the text should follow for its baseline 1628 * @param hOffset The distance along the path to add to the text's 1629 * starting position 1630 * @param vOffset The distance above(-) or below(+) the path to position 1631 * the text 1632 * @param paint The paint used for the text (e.g. color, size, style) 1633 */ 1634 public void drawTextOnPath(char[] text, int index, int count, Path path, 1635 float hOffset, float vOffset, Paint paint) { 1636 if (index < 0 || index + count > text.length) { 1637 throw new ArrayIndexOutOfBoundsException(); 1638 } 1639 native_drawTextOnPath(mNativeCanvas, text, index, count, 1640 path.ni(), hOffset, vOffset, 1641 paint.mBidiFlags, paint.mNativePaint); 1642 } 1643 1644 /** 1645 * Draw the text, with origin at (x,y), using the specified paint, along 1646 * the specified path. The paint's Align setting determins where along the 1647 * path to start the text. 1648 * 1649 * @param text The text to be drawn 1650 * @param path The path the text should follow for its baseline 1651 * @param hOffset The distance along the path to add to the text's 1652 * starting position 1653 * @param vOffset The distance above(-) or below(+) the path to position 1654 * the text 1655 * @param paint The paint used for the text (e.g. color, size, style) 1656 */ 1657 public void drawTextOnPath(String text, Path path, float hOffset, float vOffset, Paint paint) { 1658 if (text.length() > 0) { 1659 native_drawTextOnPath(mNativeCanvas, text, path.ni(), hOffset, vOffset, 1660 paint.mBidiFlags, paint.mNativePaint); 1661 } 1662 } 1663 1664 /** 1665 * Save the canvas state, draw the picture, and restore the canvas state. 1666 * This differs from picture.draw(canvas), which does not perform any 1667 * save/restore. 1668 * 1669 * <p> 1670 * <strong>Note:</strong> This forces the picture to internally call 1671 * {@link Picture#endRecording} in order to prepare for playback. 1672 * 1673 * @param picture The picture to be drawn 1674 */ 1675 public void drawPicture(Picture picture) { 1676 picture.endRecording(); 1677 int restoreCount = save(); 1678 picture.draw(this); 1679 restoreToCount(restoreCount); 1680 } 1681 1682 /** 1683 * Draw the picture, stretched to fit into the dst rectangle. 1684 */ 1685 public void drawPicture(Picture picture, RectF dst) { 1686 save(); 1687 translate(dst.left, dst.top); 1688 if (picture.getWidth() > 0 && picture.getHeight() > 0) { 1689 scale(dst.width() / picture.getWidth(), dst.height() / picture.getHeight()); 1690 } 1691 drawPicture(picture); 1692 restore(); 1693 } 1694 1695 /** 1696 * Draw the picture, stretched to fit into the dst rectangle. 1697 */ 1698 public void drawPicture(Picture picture, Rect dst) { 1699 save(); 1700 translate(dst.left, dst.top); 1701 if (picture.getWidth() > 0 && picture.getHeight() > 0) { 1702 scale((float) dst.width() / picture.getWidth(), 1703 (float) dst.height() / picture.getHeight()); 1704 } 1705 drawPicture(picture); 1706 restore(); 1707 } 1708 1709 /** 1710 * Releases the resources associated with this canvas. 1711 * 1712 * @hide 1713 */ 1714 public void release() { 1715 mFinalizer.dispose(); 1716 } 1717 1718 /** 1719 * Free up as much memory as possible from private caches (e.g. fonts, images) 1720 * 1721 * @hide 1722 */ 1723 public static native void freeCaches(); 1724 1725 /** 1726 * Free up text layout caches 1727 * 1728 * @hide 1729 */ 1730 public static native void freeTextLayoutCaches(); 1731 1732 private static native long initRaster(long nativeBitmapOrZero); 1733 private static native void copyNativeCanvasState(long nativeSrcCanvas, 1734 long nativeDstCanvas); 1735 private static native int native_saveLayer(long nativeCanvas, 1736 RectF bounds, 1737 long nativePaint, 1738 int layerFlags); 1739 private static native int native_saveLayer(long nativeCanvas, float l, 1740 float t, float r, float b, 1741 long nativePaint, 1742 int layerFlags); 1743 private static native int native_saveLayerAlpha(long nativeCanvas, 1744 RectF bounds, int alpha, 1745 int layerFlags); 1746 private static native int native_saveLayerAlpha(long nativeCanvas, float l, 1747 float t, float r, float b, 1748 int alpha, int layerFlags); 1749 1750 private static native void native_concat(long nativeCanvas, 1751 long nativeMatrix); 1752 private static native void native_setMatrix(long nativeCanvas, 1753 long nativeMatrix); 1754 private static native boolean native_clipRect(long nativeCanvas, 1755 float left, float top, 1756 float right, float bottom, 1757 int regionOp); 1758 private static native boolean native_clipPath(long nativeCanvas, 1759 long nativePath, 1760 int regionOp); 1761 private static native boolean native_clipRegion(long nativeCanvas, 1762 long nativeRegion, 1763 int regionOp); 1764 private static native void nativeSetDrawFilter(long nativeCanvas, 1765 long nativeFilter); 1766 private static native boolean native_getClipBounds(long nativeCanvas, 1767 Rect bounds); 1768 private static native void native_getCTM(long nativeCanvas, 1769 long nativeMatrix); 1770 private static native boolean native_quickReject(long nativeCanvas, 1771 RectF rect); 1772 private static native boolean native_quickReject(long nativeCanvas, 1773 long nativePath); 1774 private static native boolean native_quickReject(long nativeCanvas, 1775 float left, float top, 1776 float right, float bottom); 1777 private static native void native_drawRGB(long nativeCanvas, int r, int g, 1778 int b); 1779 private static native void native_drawARGB(long nativeCanvas, int a, int r, 1780 int g, int b); 1781 private static native void native_drawColor(long nativeCanvas, int color); 1782 private static native void native_drawColor(long nativeCanvas, int color, 1783 int mode); 1784 private static native void native_drawPaint(long nativeCanvas, 1785 long nativePaint); 1786 private static native void native_drawLine(long nativeCanvas, float startX, 1787 float startY, float stopX, 1788 float stopY, long nativePaint); 1789 private static native void native_drawRect(long nativeCanvas, RectF rect, 1790 long nativePaint); 1791 private static native void native_drawRect(long nativeCanvas, float left, 1792 float top, float right, 1793 float bottom, 1794 long nativePaint); 1795 private static native void native_drawOval(long nativeCanvas, RectF oval, 1796 long nativePaint); 1797 private static native void native_drawCircle(long nativeCanvas, float cx, 1798 float cy, float radius, 1799 long nativePaint); 1800 private static native void native_drawArc(long nativeCanvas, RectF oval, 1801 float startAngle, float sweep, 1802 boolean useCenter, 1803 long nativePaint); 1804 private static native void native_drawRoundRect(long nativeCanvas, 1805 RectF rect, float rx, 1806 float ry, long nativePaint); 1807 private static native void native_drawPath(long nativeCanvas, 1808 long nativePath, 1809 long nativePaint); 1810 private native void native_drawBitmap(long nativeCanvas, long nativeBitmap, 1811 float left, float top, 1812 long nativePaintOrZero, 1813 int canvasDensity, 1814 int screenDensity, 1815 int bitmapDensity); 1816 private native void native_drawBitmap(long nativeCanvas, long nativeBitmap, 1817 Rect src, RectF dst, 1818 long nativePaintOrZero, 1819 int screenDensity, 1820 int bitmapDensity); 1821 private static native void native_drawBitmap(long nativeCanvas, 1822 long nativeBitmap, 1823 Rect src, Rect dst, 1824 long nativePaintOrZero, 1825 int screenDensity, 1826 int bitmapDensity); 1827 private static native void native_drawBitmap(long nativeCanvas, int[] colors, 1828 int offset, int stride, float x, 1829 float y, int width, int height, 1830 boolean hasAlpha, 1831 long nativePaintOrZero); 1832 private static native void nativeDrawBitmapMatrix(long nativeCanvas, 1833 long nativeBitmap, 1834 long nativeMatrix, 1835 long nativePaint); 1836 private static native void nativeDrawBitmapMesh(long nativeCanvas, 1837 long nativeBitmap, 1838 int meshWidth, int meshHeight, 1839 float[] verts, int vertOffset, 1840 int[] colors, int colorOffset, 1841 long nativePaint); 1842 private static native void nativeDrawVertices(long nativeCanvas, int mode, int n, 1843 float[] verts, int vertOffset, float[] texs, int texOffset, 1844 int[] colors, int colorOffset, short[] indices, 1845 int indexOffset, int indexCount, long nativePaint); 1846 1847 private static native void native_drawText(long nativeCanvas, char[] text, 1848 int index, int count, float x, 1849 float y, int flags, long nativePaint, 1850 long nativeTypeface); 1851 private static native void native_drawText(long nativeCanvas, String text, 1852 int start, int end, float x, 1853 float y, int flags, long nativePaint, 1854 long nativeTypeface); 1855 1856 private static native void native_drawTextRun(long nativeCanvas, String text, 1857 int start, int end, int contextStart, int contextEnd, 1858 float x, float y, int flags, long nativePaint, long nativeTypeface); 1859 1860 private static native void native_drawTextRun(long nativeCanvas, char[] text, 1861 int start, int count, int contextStart, int contextCount, 1862 float x, float y, int flags, long nativePaint, long nativeTypeface); 1863 1864 private static native void native_drawPosText(long nativeCanvas, 1865 char[] text, int index, 1866 int count, float[] pos, 1867 long nativePaint); 1868 private static native void native_drawPosText(long nativeCanvas, 1869 String text, float[] pos, 1870 long nativePaint); 1871 private static native void native_drawTextOnPath(long nativeCanvas, 1872 char[] text, int index, 1873 int count, long nativePath, 1874 float hOffset, 1875 float vOffset, int bidiFlags, 1876 long nativePaint); 1877 private static native void native_drawTextOnPath(long nativeCanvas, 1878 String text, long nativePath, 1879 float hOffset, 1880 float vOffset, 1881 int flags, long nativePaint); 1882 private static native void finalizer(long nativeCanvas); 1883} 1884