Canvas.java revision 667fe1039feae068d3333de8fb7115313f4a517b
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 24import javax.microedition.khronos.opengles.GL; 25 26/** 27 * The Canvas class holds the "draw" calls. To draw something, you need 28 * 4 basic components: A Bitmap to hold the pixels, a Canvas to host 29 * the draw calls (writing into the bitmap), a drawing primitive (e.g. Rect, 30 * Path, text, Bitmap), and a paint (to describe the colors and styles for the 31 * drawing). 32 * 33 * <div class="special reference"> 34 * <h3>Developer Guides</h3> 35 * <p>For more information about how to use Canvas, read the 36 * <a href="{@docRoot}guide/topics/graphics/2d-graphics.html"> 37 * Canvas and Drawables</a> developer guide.</p></div> 38 */ 39public class Canvas { 40 41 // assigned in constructors or setBitmap, freed in finalizer 42 /** @hide */ 43 public int mNativeCanvas; 44 45 // may be null 46 private Bitmap mBitmap; 47 48 // optional field set by the caller 49 private DrawFilter mDrawFilter; 50 51 /** 52 * @hide 53 */ 54 protected int mDensity = Bitmap.DENSITY_NONE; 55 56 /** 57 * Used to determine when compatibility scaling is in effect. 58 * 59 * @hide 60 */ 61 protected int mScreenDensity = Bitmap.DENSITY_NONE; 62 63 // Used by native code 64 @SuppressWarnings("UnusedDeclaration") 65 private int mSurfaceFormat; 66 67 /** 68 * Flag for drawTextRun indicating left-to-right run direction. 69 * @hide 70 */ 71 public static final int DIRECTION_LTR = 0; 72 73 /** 74 * Flag for drawTextRun indicating right-to-left run direction. 75 * @hide 76 */ 77 public static final int DIRECTION_RTL = 1; 78 79 // Maximum bitmap size as defined in Skia's native code 80 // (see SkCanvas.cpp, SkDraw.cpp) 81 private static final int MAXMIMUM_BITMAP_SIZE = 32766; 82 83 // This field is used to finalize the native Canvas properly 84 private final CanvasFinalizer mFinalizer; 85 86 private static final class CanvasFinalizer { 87 private int mNativeCanvas; 88 89 public CanvasFinalizer(int nativeCanvas) { 90 mNativeCanvas = nativeCanvas; 91 } 92 93 @Override 94 protected void finalize() throws Throwable { 95 try { 96 dispose(); 97 } finally { 98 super.finalize(); 99 } 100 } 101 102 public void dispose() { 103 if (mNativeCanvas != 0) { 104 finalizer(mNativeCanvas); 105 mNativeCanvas = 0; 106 } 107 } 108 } 109 110 /** 111 * Construct an empty raster canvas. Use setBitmap() to specify a bitmap to 112 * draw into. The initial target density is {@link Bitmap#DENSITY_NONE}; 113 * this will typically be replaced when a target bitmap is set for the 114 * canvas. 115 */ 116 public Canvas() { 117 // 0 means no native bitmap 118 mNativeCanvas = initRaster(0); 119 mFinalizer = new CanvasFinalizer(mNativeCanvas); 120 } 121 122 /** 123 * Construct a canvas with the specified bitmap to draw into. The bitmap 124 * must be mutable. 125 * 126 * <p>The initial target density of the canvas is the same as the given 127 * bitmap's density. 128 * 129 * @param bitmap Specifies a mutable bitmap for the canvas to draw into. 130 */ 131 public Canvas(Bitmap bitmap) { 132 if (!bitmap.isMutable()) { 133 throw new IllegalStateException("Immutable bitmap passed to Canvas constructor"); 134 } 135 throwIfRecycled(bitmap); 136 mNativeCanvas = initRaster(bitmap.ni()); 137 mFinalizer = new CanvasFinalizer(mNativeCanvas); 138 mBitmap = bitmap; 139 mDensity = bitmap.mDensity; 140 } 141 142 /** @hide */ 143 public Canvas(int nativeCanvas) { 144 if (nativeCanvas == 0) { 145 throw new IllegalStateException(); 146 } 147 mNativeCanvas = nativeCanvas; 148 mFinalizer = new CanvasFinalizer(mNativeCanvas); 149 mDensity = Bitmap.getDefaultDensity(); 150 } 151 152 /** 153 * Replace existing canvas while ensuring that the swap has occurred before 154 * the previous native canvas is unreferenced. 155 */ 156 private void safeCanvasSwap(int nativeCanvas, boolean copyState) { 157 final int oldCanvas = mNativeCanvas; 158 mNativeCanvas = nativeCanvas; 159 mFinalizer.mNativeCanvas = nativeCanvas; 160 if (copyState) { 161 copyNativeCanvasState(oldCanvas, mNativeCanvas); 162 } 163 finalizer(oldCanvas); 164 } 165 166 /** 167 * Gets the native canvas pointer. 168 * 169 * @return The native pointer. 170 * 171 * @hide 172 */ 173 public int getNativeCanvas() { 174 return mNativeCanvas; 175 } 176 177 /** 178 * Returns null. 179 * 180 * @deprecated This method is not supported and should not be invoked. 181 * 182 * @hide 183 */ 184 @Deprecated 185 protected GL getGL() { 186 return null; 187 } 188 189 /** 190 * Indicates whether this Canvas uses hardware acceleration. 191 * 192 * Note that this method does not define what type of hardware acceleration 193 * may or may not be used. 194 * 195 * @return True if drawing operations are hardware accelerated, 196 * false otherwise. 197 */ 198 public boolean isHardwareAccelerated() { 199 return false; 200 } 201 202 /** 203 * Specify a bitmap for the canvas to draw into. All canvas state such as 204 * layers, filters, and the save/restore stack are reset with the exception 205 * of the current matrix and clip stack. Additionally, as a side-effect 206 * the canvas' target density is updated to match that of the bitmap. 207 * 208 * @param bitmap Specifies a mutable bitmap for the canvas to draw into. 209 * @see #setDensity(int) 210 * @see #getDensity() 211 */ 212 public void setBitmap(Bitmap bitmap) { 213 if (isHardwareAccelerated()) { 214 throw new RuntimeException("Can't set a bitmap device on a GL canvas"); 215 } 216 217 if (bitmap == null) { 218 safeCanvasSwap(initRaster(0), false); 219 mDensity = Bitmap.DENSITY_NONE; 220 } else { 221 if (!bitmap.isMutable()) { 222 throw new IllegalStateException(); 223 } 224 throwIfRecycled(bitmap); 225 226 safeCanvasSwap(initRaster(bitmap.ni()), true); 227 mDensity = bitmap.mDensity; 228 } 229 230 mBitmap = bitmap; 231 } 232 233 /** 234 * Set the viewport dimensions if this canvas is GL based. If it is not, 235 * this method is ignored and no exception is thrown. 236 * 237 * @param width The width of the viewport 238 * @param height The height of the viewport 239 * 240 * @hide 241 */ 242 public void setViewport(int width, int height) { 243 } 244 245 /** 246 * Return true if the device that the current layer draws into is opaque 247 * (i.e. does not support per-pixel alpha). 248 * 249 * @return true if the device that the current layer draws into is opaque 250 */ 251 public native boolean isOpaque(); 252 253 /** 254 * Returns the width of the current drawing layer 255 * 256 * @return the width of the current drawing layer 257 */ 258 public native int getWidth(); 259 260 /** 261 * Returns the height of the current drawing layer 262 * 263 * @return the height of the current drawing layer 264 */ 265 public native int getHeight(); 266 267 /** 268 * <p>Returns the target density of the canvas. The default density is 269 * derived from the density of its backing bitmap, or 270 * {@link Bitmap#DENSITY_NONE} if there is not one.</p> 271 * 272 * @return Returns the current target density of the canvas, which is used 273 * to determine the scaling factor when drawing a bitmap into it. 274 * 275 * @see #setDensity(int) 276 * @see Bitmap#getDensity() 277 */ 278 public int getDensity() { 279 return mDensity; 280 } 281 282 /** 283 * <p>Specifies the density for this Canvas' backing bitmap. This modifies 284 * the target density of the canvas itself, as well as the density of its 285 * backing bitmap via {@link Bitmap#setDensity(int) Bitmap.setDensity(int)}. 286 * 287 * @param density The new target density of the canvas, which is used 288 * to determine the scaling factor when drawing a bitmap into it. Use 289 * {@link Bitmap#DENSITY_NONE} to disable bitmap scaling. 290 * 291 * @see #getDensity() 292 * @see Bitmap#setDensity(int) 293 */ 294 public void setDensity(int density) { 295 if (mBitmap != null) { 296 mBitmap.setDensity(density); 297 } 298 mDensity = density; 299 } 300 301 /** @hide */ 302 public void setScreenDensity(int density) { 303 mScreenDensity = density; 304 } 305 306 /** 307 * Returns the maximum allowed width for bitmaps drawn with this canvas. 308 * Attempting to draw with a bitmap wider than this value will result 309 * in an error. 310 * 311 * @see #getMaximumBitmapHeight() 312 */ 313 public int getMaximumBitmapWidth() { 314 return MAXMIMUM_BITMAP_SIZE; 315 } 316 317 /** 318 * Returns the maximum allowed height for bitmaps drawn with this canvas. 319 * Attempting to draw with a bitmap taller than this value will result 320 * in an error. 321 * 322 * @see #getMaximumBitmapWidth() 323 */ 324 public int getMaximumBitmapHeight() { 325 return MAXMIMUM_BITMAP_SIZE; 326 } 327 328 // the SAVE_FLAG constants must match their native equivalents 329 330 /** restore the current matrix when restore() is called */ 331 public static final int MATRIX_SAVE_FLAG = 0x01; 332 /** restore the current clip when restore() is called */ 333 public static final int CLIP_SAVE_FLAG = 0x02; 334 /** the layer needs to per-pixel alpha */ 335 public static final int HAS_ALPHA_LAYER_SAVE_FLAG = 0x04; 336 /** the layer needs to 8-bits per color component */ 337 public static final int FULL_COLOR_LAYER_SAVE_FLAG = 0x08; 338 /** clip against the layer's bounds */ 339 public static final int CLIP_TO_LAYER_SAVE_FLAG = 0x10; 340 /** restore everything when restore() is called */ 341 public static final int ALL_SAVE_FLAG = 0x1F; 342 343 /** 344 * Saves the current matrix and clip onto a private stack. Subsequent 345 * calls to translate,scale,rotate,skew,concat or clipRect,clipPath 346 * will all operate as usual, but when the balancing call to restore() 347 * is made, those calls will be forgotten, and the settings that existed 348 * before the save() will be reinstated. 349 * 350 * @return The value to pass to restoreToCount() to balance this save() 351 */ 352 public native int save(); 353 354 /** 355 * Based on saveFlags, can save the current matrix and clip onto a private 356 * stack. Subsequent calls to translate,scale,rotate,skew,concat or 357 * clipRect,clipPath will all operate as usual, but when the balancing 358 * call to restore() is made, those calls will be forgotten, and the 359 * settings that existed before the save() will be reinstated. 360 * 361 * @param saveFlags flag bits that specify which parts of the Canvas state 362 * to save/restore 363 * @return The value to pass to restoreToCount() to balance this save() 364 */ 365 public native int save(int saveFlags); 366 367 /** 368 * This behaves the same as save(), but in addition it allocates an 369 * offscreen bitmap. All drawing calls are directed there, and only when 370 * the balancing call to restore() is made is that offscreen transfered to 371 * the canvas (or the previous layer). Subsequent calls to translate, 372 * scale, rotate, skew, concat or clipRect, clipPath all operate on this 373 * copy. When the balancing call to restore() is made, this copy is 374 * deleted and the previous matrix/clip state is restored. 375 * 376 * @param bounds May be null. The maximum size the offscreen bitmap 377 * needs to be (in local coordinates) 378 * @param paint This is copied, and is applied to the offscreen when 379 * restore() is called. 380 * @param saveFlags see _SAVE_FLAG constants 381 * @return value to pass to restoreToCount() to balance this save() 382 */ 383 public int saveLayer(RectF bounds, Paint paint, int saveFlags) { 384 return native_saveLayer(mNativeCanvas, bounds, 385 paint != null ? paint.mNativePaint : 0, 386 saveFlags); 387 } 388 389 /** 390 * Helper version of saveLayer() that takes 4 values rather than a RectF. 391 */ 392 public int saveLayer(float left, float top, float right, float bottom, Paint paint, 393 int saveFlags) { 394 return native_saveLayer(mNativeCanvas, left, top, right, bottom, 395 paint != null ? paint.mNativePaint : 0, 396 saveFlags); 397 } 398 399 /** 400 * This behaves the same as save(), but in addition it allocates an 401 * offscreen bitmap. All drawing calls are directed there, and only when 402 * the balancing call to restore() is made is that offscreen transfered to 403 * the canvas (or the previous layer). Subsequent calls to translate, 404 * scale, rotate, skew, concat or clipRect, clipPath all operate on this 405 * copy. When the balancing call to restore() is made, this copy is 406 * deleted and the previous matrix/clip state is restored. 407 * 408 * @param bounds The maximum size the offscreen bitmap needs to be 409 * (in local coordinates) 410 * @param alpha The alpha to apply to the offscreen when when it is 411 drawn during restore() 412 * @param saveFlags see _SAVE_FLAG constants 413 * @return value to pass to restoreToCount() to balance this call 414 */ 415 public int saveLayerAlpha(RectF bounds, int alpha, int saveFlags) { 416 alpha = Math.min(255, Math.max(0, alpha)); 417 return native_saveLayerAlpha(mNativeCanvas, bounds, alpha, saveFlags); 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 * This call balances a previous call to save(), and is used to remove all 431 * modifications to the matrix/clip state since the last save call. It is 432 * an error to call restore() more times than save() was called. 433 */ 434 public native void restore(); 435 436 /** 437 * Returns the number of matrix/clip states on the Canvas' private stack. 438 * This will equal # save() calls - # restore() calls. 439 */ 440 public native int getSaveCount(); 441 442 /** 443 * Efficient way to pop any calls to save() that happened after the save 444 * count reached saveCount. It is an error for saveCount to be less than 1. 445 * 446 * Example: 447 * int count = canvas.save(); 448 * ... // more calls potentially to save() 449 * canvas.restoreToCount(count); 450 * // now the canvas is back in the same state it was before the initial 451 * // call to save(). 452 * 453 * @param saveCount The save level to restore to. 454 */ 455 public native void restoreToCount(int saveCount); 456 457 /** 458 * Preconcat the current matrix with the specified translation 459 * 460 * @param dx The distance to translate in X 461 * @param dy The distance to translate in Y 462 */ 463 public native void translate(float dx, float dy); 464 465 /** 466 * Preconcat the current matrix with the specified scale. 467 * 468 * @param sx The amount to scale in X 469 * @param sy The amount to scale in Y 470 */ 471 public native void scale(float sx, float sy); 472 473 /** 474 * Preconcat the current matrix with the specified scale. 475 * 476 * @param sx The amount to scale in X 477 * @param sy The amount to scale in Y 478 * @param px The x-coord for the pivot point (unchanged by the scale) 479 * @param py The y-coord for the pivot point (unchanged by the scale) 480 */ 481 public final void scale(float sx, float sy, float px, float py) { 482 translate(px, py); 483 scale(sx, sy); 484 translate(-px, -py); 485 } 486 487 /** 488 * Preconcat the current matrix with the specified rotation. 489 * 490 * @param degrees The amount to rotate, in degrees 491 */ 492 public native void rotate(float degrees); 493 494 /** 495 * Preconcat the current matrix with the specified rotation. 496 * 497 * @param degrees The amount to rotate, in degrees 498 * @param px The x-coord for the pivot point (unchanged by the rotation) 499 * @param py The y-coord for the pivot point (unchanged by the rotation) 500 */ 501 public final void rotate(float degrees, float px, float py) { 502 translate(px, py); 503 rotate(degrees); 504 translate(-px, -py); 505 } 506 507 /** 508 * Preconcat the current matrix with the specified skew. 509 * 510 * @param sx The amount to skew in X 511 * @param sy The amount to skew in Y 512 */ 513 public native void skew(float sx, float sy); 514 515 /** 516 * Preconcat the current matrix with the specified matrix. If the specified 517 * matrix is null, this method does nothing. 518 * 519 * @param matrix The matrix to preconcatenate with the current matrix 520 */ 521 public void concat(Matrix matrix) { 522 if (matrix != null) native_concat(mNativeCanvas, matrix.native_instance); 523 } 524 525 /** 526 * Completely replace the current matrix with the specified matrix. If the 527 * matrix parameter is null, then the current matrix is reset to identity. 528 * 529 * <strong>Note:</strong> it is recommended to use {@link #concat(Matrix)}, 530 * {@link #scale(float, float)}, {@link #translate(float, float)} and 531 * {@link #rotate(float)} instead of this method. 532 * 533 * @param matrix The matrix to replace the current matrix with. If it is 534 * null, set the current matrix to identity. 535 * 536 * @see #concat(Matrix) 537 */ 538 public void setMatrix(Matrix matrix) { 539 native_setMatrix(mNativeCanvas, 540 matrix == null ? 0 : matrix.native_instance); 541 } 542 543 /** 544 * Return, in ctm, the current transformation matrix. This does not alter 545 * the matrix in the canvas, but just returns a copy of it. 546 */ 547 @Deprecated 548 public void getMatrix(Matrix ctm) { 549 native_getCTM(mNativeCanvas, ctm.native_instance); 550 } 551 552 /** 553 * Return a new matrix with a copy of the canvas' current transformation 554 * matrix. 555 */ 556 @Deprecated 557 public final Matrix getMatrix() { 558 Matrix m = new Matrix(); 559 //noinspection deprecation 560 getMatrix(m); 561 return m; 562 } 563 564 /** 565 * Modify the current clip with the specified rectangle. 566 * 567 * @param rect The rect to intersect with the current clip 568 * @param op How the clip is modified 569 * @return true if the resulting clip is non-empty 570 */ 571 public boolean clipRect(RectF rect, Region.Op op) { 572 return native_clipRect(mNativeCanvas, rect.left, rect.top, rect.right, rect.bottom, 573 op.nativeInt); 574 } 575 576 /** 577 * Modify the current clip with the specified rectangle, which is 578 * expressed in local coordinates. 579 * 580 * @param rect The rectangle to intersect with the current clip. 581 * @param op How the clip is modified 582 * @return true if the resulting clip is non-empty 583 */ 584 public boolean clipRect(Rect rect, Region.Op op) { 585 return native_clipRect(mNativeCanvas, rect.left, rect.top, rect.right, rect.bottom, 586 op.nativeInt); 587 } 588 589 /** 590 * Intersect the current clip with the specified rectangle, which is 591 * expressed in local coordinates. 592 * 593 * @param rect The rectangle to intersect with the current clip. 594 * @return true if the resulting clip is non-empty 595 */ 596 public native boolean clipRect(RectF rect); 597 598 /** 599 * Intersect the current clip with the specified rectangle, which is 600 * expressed in local coordinates. 601 * 602 * @param rect The rectangle to intersect with the current clip. 603 * @return true if the resulting clip is non-empty 604 */ 605 public native boolean clipRect(Rect rect); 606 607 /** 608 * Modify the current clip with the specified rectangle, which is 609 * expressed in local coordinates. 610 * 611 * @param left The left side of the rectangle to intersect with the 612 * current clip 613 * @param top The top of the rectangle to intersect with the current 614 * clip 615 * @param right The right side of the rectangle to intersect with the 616 * current clip 617 * @param bottom The bottom of the rectangle to intersect with the current 618 * clip 619 * @param op How the clip is modified 620 * @return true if the resulting clip is non-empty 621 */ 622 public boolean clipRect(float left, float top, float right, float bottom, Region.Op op) { 623 return native_clipRect(mNativeCanvas, left, top, right, bottom, op.nativeInt); 624 } 625 626 /** 627 * Intersect the current clip with the specified rectangle, which is 628 * expressed in local coordinates. 629 * 630 * @param left The left side of the rectangle to intersect with the 631 * current clip 632 * @param top The top of the rectangle to intersect with the current clip 633 * @param right The right side of the rectangle to intersect with the 634 * current clip 635 * @param bottom The bottom of the rectangle to intersect with the current 636 * clip 637 * @return true if the resulting clip is non-empty 638 */ 639 public native boolean clipRect(float left, float top, float right, float bottom); 640 641 /** 642 * Intersect the current clip with the specified rectangle, which is 643 * expressed in local coordinates. 644 * 645 * @param left The left side of the rectangle to intersect with the 646 * current clip 647 * @param top The top of the rectangle to intersect with the current clip 648 * @param right The right side of the rectangle to intersect with the 649 * current clip 650 * @param bottom The bottom of the rectangle to intersect with the current 651 * clip 652 * @return true if the resulting clip is non-empty 653 */ 654 public native boolean clipRect(int left, int top, int right, int bottom); 655 656 /** 657 * Modify the current clip with the specified path. 658 * 659 * @param path The path to operate on the current clip 660 * @param op How the clip is modified 661 * @return true if the resulting is non-empty 662 */ 663 public boolean clipPath(Path path, Region.Op op) { 664 return native_clipPath(mNativeCanvas, path.ni(), op.nativeInt); 665 } 666 667 /** 668 * Intersect the current clip with the specified path. 669 * 670 * @param path The path to intersect with the current clip 671 * @return true if the resulting is non-empty 672 */ 673 public boolean clipPath(Path path) { 674 return clipPath(path, Region.Op.INTERSECT); 675 } 676 677 /** 678 * Modify the current clip with the specified region. Note that unlike 679 * clipRect() and clipPath() which transform their arguments by the 680 * current matrix, clipRegion() assumes its argument is already in the 681 * coordinate system of the current layer's bitmap, and so not 682 * transformation is performed. 683 * 684 * @param region The region to operate on the current clip, based on op 685 * @param op How the clip is modified 686 * @return true if the resulting is non-empty 687 */ 688 public boolean clipRegion(Region region, Region.Op op) { 689 return native_clipRegion(mNativeCanvas, region.ni(), op.nativeInt); 690 } 691 692 /** 693 * Intersect the current clip with the specified region. Note that unlike 694 * clipRect() and clipPath() which transform their arguments by the 695 * current matrix, clipRegion() assumes its argument is already in the 696 * coordinate system of the current layer's bitmap, and so not 697 * transformation is performed. 698 * 699 * @param region The region to operate on the current clip, based on op 700 * @return true if the resulting is non-empty 701 */ 702 public boolean clipRegion(Region region) { 703 return clipRegion(region, Region.Op.INTERSECT); 704 } 705 706 public DrawFilter getDrawFilter() { 707 return mDrawFilter; 708 } 709 710 public void setDrawFilter(DrawFilter filter) { 711 int nativeFilter = 0; 712 if (filter != null) { 713 nativeFilter = filter.mNativeInt; 714 } 715 mDrawFilter = filter; 716 nativeSetDrawFilter(mNativeCanvas, nativeFilter); 717 } 718 719 public enum EdgeType { 720 721 /** 722 * Black-and-White: Treat edges by just rounding to nearest pixel boundary 723 */ 724 BW(0), //!< treat edges by just rounding to nearest pixel boundary 725 726 /** 727 * Antialiased: Treat edges by rounding-out, since they may be antialiased 728 */ 729 AA(1); 730 731 EdgeType(int nativeInt) { 732 this.nativeInt = nativeInt; 733 } 734 735 /** 736 * @hide 737 */ 738 public final int nativeInt; 739 } 740 741 /** 742 * Return true if the specified rectangle, after being transformed by the 743 * current matrix, would lie completely outside of the current clip. Call 744 * this to check if an area you intend to draw into is clipped out (and 745 * therefore you can skip making the draw calls). 746 * 747 * @param rect the rect to compare with the current clip 748 * @param type {@link Canvas.EdgeType#AA} if the path should be considered antialiased, 749 * since that means it may affect a larger area (more pixels) than 750 * non-antialiased ({@link Canvas.EdgeType#BW}). 751 * @return true if the rect (transformed by the canvas' matrix) 752 * does not intersect with the canvas' clip 753 */ 754 public boolean quickReject(RectF rect, EdgeType type) { 755 return native_quickReject(mNativeCanvas, rect); 756 } 757 758 /** 759 * Return true if the specified path, after being transformed by the 760 * current matrix, would lie completely outside of the current clip. Call 761 * this to check if an area you intend to draw into is clipped out (and 762 * therefore you can skip making the draw calls). Note: for speed it may 763 * return false even if the path itself might not intersect the clip 764 * (i.e. the bounds of the path intersects, but the path does not). 765 * 766 * @param path The path to compare with the current clip 767 * @param type {@link Canvas.EdgeType#AA} if the path should be considered antialiased, 768 * since that means it may affect a larger area (more pixels) than 769 * non-antialiased ({@link Canvas.EdgeType#BW}). 770 * @return true if the path (transformed by the canvas' matrix) 771 * does not intersect with the canvas' clip 772 */ 773 public boolean quickReject(Path path, EdgeType type) { 774 return native_quickReject(mNativeCanvas, path.ni()); 775 } 776 777 /** 778 * Return true if the specified rectangle, after being transformed by the 779 * current matrix, would lie completely outside of the current clip. Call 780 * this to check if an area you intend to draw into is clipped out (and 781 * therefore you can skip making the draw calls). 782 * 783 * @param left The left side of the rectangle to compare with the 784 * current clip 785 * @param top The top of the rectangle to compare with the current 786 * clip 787 * @param right The right side of the rectangle to compare with the 788 * current clip 789 * @param bottom The bottom of the rectangle to compare with the 790 * current clip 791 * @param type {@link Canvas.EdgeType#AA} if the path should be considered antialiased, 792 * since that means it may affect a larger area (more pixels) than 793 * non-antialiased ({@link Canvas.EdgeType#BW}). 794 * @return true if the rect (transformed by the canvas' matrix) 795 * does not intersect with the canvas' clip 796 */ 797 public boolean quickReject(float left, float top, float right, float bottom, 798 EdgeType type) { 799 return native_quickReject(mNativeCanvas, left, top, right, bottom); 800 } 801 802 /** 803 * Return the bounds of the current clip (in local coordinates) in the 804 * bounds parameter, and return true if it is non-empty. This can be useful 805 * in a way similar to quickReject, in that it tells you that drawing 806 * outside of these bounds will be clipped out. 807 * 808 * @param bounds Return the clip bounds here. If it is null, ignore it but 809 * still return true if the current clip is non-empty. 810 * @return true if the current clip is non-empty. 811 */ 812 public boolean getClipBounds(Rect bounds) { 813 return native_getClipBounds(mNativeCanvas, bounds); 814 } 815 816 /** 817 * Retrieve the bounds of the current clip (in local coordinates). 818 * 819 * @return the clip bounds, or [0, 0, 0, 0] if the clip is empty. 820 */ 821 public final Rect getClipBounds() { 822 Rect r = new Rect(); 823 getClipBounds(r); 824 return r; 825 } 826 827 /** 828 * Fill the entire canvas' bitmap (restricted to the current clip) with the 829 * specified RGB color, using srcover porterduff mode. 830 * 831 * @param r red component (0..255) of the color to draw onto the canvas 832 * @param g green component (0..255) of the color to draw onto the canvas 833 * @param b blue component (0..255) of the color to draw onto the canvas 834 */ 835 public void drawRGB(int r, int g, int b) { 836 native_drawRGB(mNativeCanvas, r, g, b); 837 } 838 839 /** 840 * Fill the entire canvas' bitmap (restricted to the current clip) with the 841 * specified ARGB color, using srcover porterduff mode. 842 * 843 * @param a alpha component (0..255) of the color to draw onto the canvas 844 * @param r red component (0..255) of the color to draw onto the canvas 845 * @param g green component (0..255) of the color to draw onto the canvas 846 * @param b blue component (0..255) of the color to draw onto the canvas 847 */ 848 public void drawARGB(int a, int r, int g, int b) { 849 native_drawARGB(mNativeCanvas, a, r, g, b); 850 } 851 852 /** 853 * Fill the entire canvas' bitmap (restricted to the current clip) with the 854 * specified color, using srcover porterduff mode. 855 * 856 * @param color the color to draw onto the canvas 857 */ 858 public void drawColor(int color) { 859 native_drawColor(mNativeCanvas, color); 860 } 861 862 /** 863 * Fill the entire canvas' bitmap (restricted to the current clip) with the 864 * specified color and porter-duff xfermode. 865 * 866 * @param color the color to draw with 867 * @param mode the porter-duff mode to apply to the color 868 */ 869 public void drawColor(int color, PorterDuff.Mode mode) { 870 native_drawColor(mNativeCanvas, color, mode.nativeInt); 871 } 872 873 /** 874 * Fill the entire canvas' bitmap (restricted to the current clip) with 875 * the specified paint. This is equivalent (but faster) to drawing an 876 * infinitely large rectangle with the specified paint. 877 * 878 * @param paint The paint used to draw onto the canvas 879 */ 880 public void drawPaint(Paint paint) { 881 native_drawPaint(mNativeCanvas, paint.mNativePaint); 882 } 883 884 /** 885 * Draw a series of points. Each point is centered at the coordinate 886 * specified by pts[], and its diameter is specified by the paint's stroke 887 * width (as transformed by the canvas' CTM), with special treatment for 888 * a stroke width of 0, which always draws exactly 1 pixel (or at most 4 889 * if antialiasing is enabled). The shape of the point is controlled by 890 * the paint's Cap type. The shape is a square, unless the cap type is 891 * Round, in which case the shape is a circle. 892 * 893 * @param pts Array of points to draw [x0 y0 x1 y1 x2 y2 ...] 894 * @param offset Number of values to skip before starting to draw. 895 * @param count The number of values to process, after skipping offset 896 * of them. Since one point uses two values, the number of 897 * "points" that are drawn is really (count >> 1). 898 * @param paint The paint used to draw the points 899 */ 900 public native void drawPoints(float[] pts, int offset, int count, Paint paint); 901 902 /** 903 * Helper for drawPoints() that assumes you want to draw the entire array 904 */ 905 public void drawPoints(float[] pts, Paint paint) { 906 drawPoints(pts, 0, pts.length, paint); 907 } 908 909 /** 910 * Helper for drawPoints() for drawing a single point. 911 */ 912 public native void drawPoint(float x, float y, Paint paint); 913 914 /** 915 * Draw a line segment with the specified start and stop x,y coordinates, 916 * using the specified paint. 917 * 918 * <p>Note that since a line is always "framed", the Style is ignored in the paint.</p> 919 * 920 * <p>Degenerate lines (length is 0) will not be drawn.</p> 921 * 922 * @param startX The x-coordinate of the start point of the line 923 * @param startY The y-coordinate of the start point of the line 924 * @param paint The paint used to draw the line 925 */ 926 public void drawLine(float startX, float startY, float stopX, float stopY, Paint paint) { 927 native_drawLine(mNativeCanvas, startX, startY, stopX, stopY, paint.mNativePaint); 928 } 929 930 /** 931 * Draw a series of lines. Each line is taken from 4 consecutive values 932 * in the pts array. Thus to draw 1 line, the array must contain at least 4 933 * values. This is logically the same as drawing the array as follows: 934 * drawLine(pts[0], pts[1], pts[2], pts[3]) followed by 935 * drawLine(pts[4], pts[5], pts[6], pts[7]) and so on. 936 * 937 * @param pts Array of points to draw [x0 y0 x1 y1 x2 y2 ...] 938 * @param offset Number of values in the array to skip before drawing. 939 * @param count The number of values in the array to process, after 940 * skipping "offset" of them. Since each line uses 4 values, 941 * the number of "lines" that are drawn is really 942 * (count >> 2). 943 * @param paint The paint used to draw the points 944 */ 945 public native void drawLines(float[] pts, int offset, int count, Paint paint); 946 947 public void drawLines(float[] pts, Paint paint) { 948 drawLines(pts, 0, pts.length, paint); 949 } 950 951 /** 952 * Draw the specified Rect using the specified paint. The rectangle will 953 * be filled or framed based on the Style in the paint. 954 * 955 * @param rect The rect to be drawn 956 * @param paint The paint used to draw the rect 957 */ 958 public void drawRect(RectF rect, Paint paint) { 959 native_drawRect(mNativeCanvas, rect, paint.mNativePaint); 960 } 961 962 /** 963 * Draw the specified Rect using the specified Paint. The rectangle 964 * will be filled or framed based on the Style in the paint. 965 * 966 * @param r The rectangle to be drawn. 967 * @param paint The paint used to draw the rectangle 968 */ 969 public void drawRect(Rect r, Paint paint) { 970 drawRect(r.left, r.top, r.right, r.bottom, paint); 971 } 972 973 974 /** 975 * Draw the specified Rect using the specified paint. The rectangle will 976 * be filled or framed based on the Style in the paint. 977 * 978 * @param left The left side of the rectangle to be drawn 979 * @param top The top side of the rectangle to be drawn 980 * @param right The right side of the rectangle to be drawn 981 * @param bottom The bottom side of the rectangle to be drawn 982 * @param paint The paint used to draw the rect 983 */ 984 public void drawRect(float left, float top, float right, float bottom, Paint paint) { 985 native_drawRect(mNativeCanvas, left, top, right, bottom, paint.mNativePaint); 986 } 987 988 /** 989 * Draw the specified oval using the specified paint. The oval will be 990 * filled or framed based on the Style in the paint. 991 * 992 * @param oval The rectangle bounds of the oval to be drawn 993 */ 994 public void drawOval(RectF oval, Paint paint) { 995 if (oval == null) { 996 throw new NullPointerException(); 997 } 998 native_drawOval(mNativeCanvas, oval, paint.mNativePaint); 999 } 1000 1001 /** 1002 * Draw the specified circle using the specified paint. If radius is <= 0, 1003 * then nothing will be drawn. The circle will be filled or framed based 1004 * on the Style in the paint. 1005 * 1006 * @param cx The x-coordinate of the center of the cirle to be drawn 1007 * @param cy The y-coordinate of the center of the cirle to be drawn 1008 * @param radius The radius of the cirle to be drawn 1009 * @param paint The paint used to draw the circle 1010 */ 1011 public void drawCircle(float cx, float cy, float radius, Paint paint) { 1012 native_drawCircle(mNativeCanvas, cx, cy, radius, paint.mNativePaint); 1013 } 1014 1015 /** 1016 * <p>Draw the specified arc, which will be scaled to fit inside the 1017 * specified oval.</p> 1018 * 1019 * <p>If the start angle is negative or >= 360, the start angle is treated 1020 * as start angle modulo 360.</p> 1021 * 1022 * <p>If the sweep angle is >= 360, then the oval is drawn 1023 * completely. Note that this differs slightly from SkPath::arcTo, which 1024 * treats the sweep angle modulo 360. If the sweep angle is negative, 1025 * the sweep angle is treated as sweep angle modulo 360</p> 1026 * 1027 * <p>The arc is drawn clockwise. An angle of 0 degrees correspond to the 1028 * geometric angle of 0 degrees (3 o'clock on a watch.)</p> 1029 * 1030 * @param oval The bounds of oval used to define the shape and size 1031 * of the arc 1032 * @param startAngle Starting angle (in degrees) where the arc begins 1033 * @param sweepAngle Sweep angle (in degrees) measured clockwise 1034 * @param useCenter If true, include the center of the oval in the arc, and 1035 close it if it is being stroked. This will draw a wedge 1036 * @param paint The paint used to draw the arc 1037 */ 1038 public void drawArc(RectF oval, float startAngle, float sweepAngle, boolean useCenter, 1039 Paint paint) { 1040 if (oval == null) { 1041 throw new NullPointerException(); 1042 } 1043 native_drawArc(mNativeCanvas, oval, startAngle, sweepAngle, 1044 useCenter, paint.mNativePaint); 1045 } 1046 1047 /** 1048 * Draw the specified round-rect using the specified paint. The roundrect 1049 * will be filled or framed based on the Style in the paint. 1050 * 1051 * @param rect The rectangular bounds of the roundRect to be drawn 1052 * @param rx The x-radius of the oval used to round the corners 1053 * @param ry The y-radius of the oval used to round the corners 1054 * @param paint The paint used to draw the roundRect 1055 */ 1056 public void drawRoundRect(RectF rect, float rx, float ry, Paint paint) { 1057 if (rect == null) { 1058 throw new NullPointerException(); 1059 } 1060 native_drawRoundRect(mNativeCanvas, rect, rx, ry, 1061 paint.mNativePaint); 1062 } 1063 1064 /** 1065 * Draw the specified path using the specified paint. The path will be 1066 * filled or framed based on the Style in the paint. 1067 * 1068 * @param path The path to be drawn 1069 * @param paint The paint used to draw the path 1070 */ 1071 public void drawPath(Path path, Paint paint) { 1072 native_drawPath(mNativeCanvas, path.ni(), paint.mNativePaint); 1073 } 1074 1075 private static void throwIfRecycled(Bitmap bitmap) { 1076 if (bitmap.isRecycled()) { 1077 throw new RuntimeException("Canvas: trying to use a recycled bitmap " + bitmap); 1078 } 1079 } 1080 1081 /** 1082 * Draws the specified bitmap as an N-patch (most often, a 9-patches.) 1083 * 1084 * @param patch The ninepatch object to render 1085 * @param dst The destination rectangle. 1086 * @param paint The paint to draw the bitmap with. may be null 1087 * 1088 * @hide 1089 */ 1090 public void drawPatch(NinePatch patch, Rect dst, Paint paint) { 1091 patch.drawSoftware(this, dst, paint); 1092 } 1093 1094 /** 1095 * Draws the specified bitmap as an N-patch (most often, a 9-patches.) 1096 * 1097 * @param patch The ninepatch object to render 1098 * @param dst The destination rectangle. 1099 * @param paint The paint to draw the bitmap with. may be null 1100 * 1101 * @hide 1102 */ 1103 public void drawPatch(NinePatch patch, RectF dst, Paint paint) { 1104 patch.drawSoftware(this, dst, paint); 1105 } 1106 1107 /** 1108 * Draw the specified bitmap, with its top/left corner at (x,y), using 1109 * the specified paint, transformed by the current matrix. 1110 * 1111 * <p>Note: if the paint contains a maskfilter that generates a mask which 1112 * extends beyond the bitmap's original width/height (e.g. BlurMaskFilter), 1113 * then the bitmap will be drawn as if it were in a Shader with CLAMP mode. 1114 * Thus the color outside of the original width/height will be the edge 1115 * color replicated. 1116 * 1117 * <p>If the bitmap and canvas have different densities, this function 1118 * will take care of automatically scaling the bitmap to draw at the 1119 * same density as the canvas. 1120 * 1121 * @param bitmap The bitmap to be drawn 1122 * @param left The position of the left side of the bitmap being drawn 1123 * @param top The position of the top side of the bitmap being drawn 1124 * @param paint The paint used to draw the bitmap (may be null) 1125 */ 1126 public void drawBitmap(Bitmap bitmap, float left, float top, Paint paint) { 1127 throwIfRecycled(bitmap); 1128 native_drawBitmap(mNativeCanvas, bitmap.ni(), left, top, 1129 paint != null ? paint.mNativePaint : 0, mDensity, mScreenDensity, bitmap.mDensity); 1130 } 1131 1132 /** 1133 * Draw the specified bitmap, scaling/translating automatically to fill 1134 * the destination rectangle. If the source rectangle is not null, it 1135 * specifies the subset of the bitmap to draw. 1136 * 1137 * <p>Note: if the paint contains a maskfilter that generates a mask which 1138 * extends beyond the bitmap's original width/height (e.g. BlurMaskFilter), 1139 * then the bitmap will be drawn as if it were in a Shader with CLAMP mode. 1140 * Thus the color outside of the original width/height will be the edge 1141 * color replicated. 1142 * 1143 * <p>This function <em>ignores the density associated with the bitmap</em>. 1144 * This is because the source and destination rectangle coordinate 1145 * spaces are in their respective densities, so must already have the 1146 * appropriate scaling factor applied. 1147 * 1148 * @param bitmap The bitmap to be drawn 1149 * @param src May be null. The subset of the bitmap to be drawn 1150 * @param dst The rectangle that the bitmap will be scaled/translated 1151 * to fit into 1152 * @param paint May be null. The paint used to draw the bitmap 1153 */ 1154 public void drawBitmap(Bitmap bitmap, Rect src, RectF dst, Paint paint) { 1155 if (dst == null) { 1156 throw new NullPointerException(); 1157 } 1158 throwIfRecycled(bitmap); 1159 native_drawBitmap(mNativeCanvas, bitmap.ni(), src, dst, 1160 paint != null ? paint.mNativePaint : 0, mScreenDensity, bitmap.mDensity); 1161 } 1162 1163 /** 1164 * Draw the specified bitmap, scaling/translating automatically to fill 1165 * the destination rectangle. If the source rectangle is not null, it 1166 * specifies the subset of the bitmap to draw. 1167 * 1168 * <p>Note: if the paint contains a maskfilter that generates a mask which 1169 * extends beyond the bitmap's original width/height (e.g. BlurMaskFilter), 1170 * then the bitmap will be drawn as if it were in a Shader with CLAMP mode. 1171 * Thus the color outside of the original width/height will be the edge 1172 * color replicated. 1173 * 1174 * <p>This function <em>ignores the density associated with the bitmap</em>. 1175 * This is because the source and destination rectangle coordinate 1176 * spaces are in their respective densities, so must already have the 1177 * appropriate scaling factor applied. 1178 * 1179 * @param bitmap The bitmap to be drawn 1180 * @param src May be null. The subset of the bitmap to be drawn 1181 * @param dst The rectangle that the bitmap will be scaled/translated 1182 * to fit into 1183 * @param paint May be null. The paint used to draw the bitmap 1184 */ 1185 public void drawBitmap(Bitmap bitmap, Rect src, Rect dst, Paint paint) { 1186 if (dst == null) { 1187 throw new NullPointerException(); 1188 } 1189 throwIfRecycled(bitmap); 1190 native_drawBitmap(mNativeCanvas, bitmap.ni(), src, dst, 1191 paint != null ? paint.mNativePaint : 0, mScreenDensity, bitmap.mDensity); 1192 } 1193 1194 /** 1195 * Treat the specified array of colors as a bitmap, and draw it. This gives 1196 * the same result as first creating a bitmap from the array, and then 1197 * drawing it, but this method avoids explicitly creating a bitmap object 1198 * which can be more efficient if the colors are changing often. 1199 * 1200 * @param colors Array of colors representing the pixels of the bitmap 1201 * @param offset Offset into the array of colors for the first pixel 1202 * @param stride The number of colors in the array between rows (must be 1203 * >= width or <= -width). 1204 * @param x The X coordinate for where to draw the bitmap 1205 * @param y The Y coordinate for where to draw the bitmap 1206 * @param width The width of the bitmap 1207 * @param height The height of the bitmap 1208 * @param hasAlpha True if the alpha channel of the colors contains valid 1209 * values. If false, the alpha byte is ignored (assumed to 1210 * be 0xFF for every pixel). 1211 * @param paint May be null. The paint used to draw the bitmap 1212 */ 1213 public void drawBitmap(int[] colors, int offset, int stride, float x, float y, 1214 int width, int height, boolean hasAlpha, Paint paint) { 1215 // check for valid input 1216 if (width < 0) { 1217 throw new IllegalArgumentException("width must be >= 0"); 1218 } 1219 if (height < 0) { 1220 throw new IllegalArgumentException("height must be >= 0"); 1221 } 1222 if (Math.abs(stride) < width) { 1223 throw new IllegalArgumentException("abs(stride) must be >= width"); 1224 } 1225 int lastScanline = offset + (height - 1) * stride; 1226 int length = colors.length; 1227 if (offset < 0 || (offset + width > length) || lastScanline < 0 1228 || (lastScanline + width > length)) { 1229 throw new ArrayIndexOutOfBoundsException(); 1230 } 1231 // quick escape if there's nothing to draw 1232 if (width == 0 || height == 0) { 1233 return; 1234 } 1235 // punch down to native for the actual draw 1236 native_drawBitmap(mNativeCanvas, colors, offset, stride, x, y, width, height, hasAlpha, 1237 paint != null ? paint.mNativePaint : 0); 1238 } 1239 1240 /** Legacy version of drawBitmap(int[] colors, ...) that took ints for x,y 1241 */ 1242 public void drawBitmap(int[] colors, int offset, int stride, int x, int y, 1243 int width, int height, boolean hasAlpha, Paint paint) { 1244 // call through to the common float version 1245 drawBitmap(colors, offset, stride, (float)x, (float)y, width, height, 1246 hasAlpha, paint); 1247 } 1248 1249 /** 1250 * Draw the bitmap using the specified matrix. 1251 * 1252 * @param bitmap The bitmap to draw 1253 * @param matrix The matrix used to transform the bitmap when it is drawn 1254 * @param paint May be null. The paint used to draw the bitmap 1255 */ 1256 public void drawBitmap(Bitmap bitmap, Matrix matrix, Paint paint) { 1257 nativeDrawBitmapMatrix(mNativeCanvas, bitmap.ni(), matrix.ni(), 1258 paint != null ? paint.mNativePaint : 0); 1259 } 1260 1261 /** 1262 * @hide 1263 */ 1264 protected static void checkRange(int length, int offset, int count) { 1265 if ((offset | count) < 0 || offset + count > length) { 1266 throw new ArrayIndexOutOfBoundsException(); 1267 } 1268 } 1269 1270 /** 1271 * Draw the bitmap through the mesh, where mesh vertices are evenly 1272 * distributed across the bitmap. There are meshWidth+1 vertices across, and 1273 * meshHeight+1 vertices down. The verts array is accessed in row-major 1274 * order, so that the first meshWidth+1 vertices are distributed across the 1275 * top of the bitmap from left to right. A more general version of this 1276 * method is drawVertices(). 1277 * 1278 * @param bitmap The bitmap to draw using the mesh 1279 * @param meshWidth The number of columns in the mesh. Nothing is drawn if 1280 * this is 0 1281 * @param meshHeight The number of rows in the mesh. Nothing is drawn if 1282 * this is 0 1283 * @param verts Array of x,y pairs, specifying where the mesh should be 1284 * drawn. There must be at least 1285 * (meshWidth+1) * (meshHeight+1) * 2 + vertOffset values 1286 * in the array 1287 * @param vertOffset Number of verts elements to skip before drawing 1288 * @param colors May be null. Specifies a color at each vertex, which is 1289 * interpolated across the cell, and whose values are 1290 * multiplied by the corresponding bitmap colors. If not null, 1291 * there must be at least (meshWidth+1) * (meshHeight+1) + 1292 * colorOffset values in the array. 1293 * @param colorOffset Number of color elements to skip before drawing 1294 * @param paint May be null. The paint used to draw the bitmap 1295 */ 1296 public void drawBitmapMesh(Bitmap bitmap, int meshWidth, int meshHeight, 1297 float[] verts, int vertOffset, int[] colors, int colorOffset, Paint paint) { 1298 if ((meshWidth | meshHeight | vertOffset | colorOffset) < 0) { 1299 throw new ArrayIndexOutOfBoundsException(); 1300 } 1301 if (meshWidth == 0 || meshHeight == 0) { 1302 return; 1303 } 1304 int count = (meshWidth + 1) * (meshHeight + 1); 1305 // we mul by 2 since we need two floats per vertex 1306 checkRange(verts.length, vertOffset, count * 2); 1307 if (colors != null) { 1308 // no mul by 2, since we need only 1 color per vertex 1309 checkRange(colors.length, colorOffset, count); 1310 } 1311 nativeDrawBitmapMesh(mNativeCanvas, bitmap.ni(), meshWidth, meshHeight, 1312 verts, vertOffset, colors, colorOffset, 1313 paint != null ? paint.mNativePaint : 0); 1314 } 1315 1316 public enum VertexMode { 1317 TRIANGLES(0), 1318 TRIANGLE_STRIP(1), 1319 TRIANGLE_FAN(2); 1320 1321 VertexMode(int nativeInt) { 1322 this.nativeInt = nativeInt; 1323 } 1324 1325 /** 1326 * @hide 1327 */ 1328 public final int nativeInt; 1329 } 1330 1331 /** 1332 * Draw the array of vertices, interpreted as triangles (based on mode). The 1333 * verts array is required, and specifies the x,y pairs for each vertex. If 1334 * texs is non-null, then it is used to specify the coordinate in shader 1335 * coordinates to use at each vertex (the paint must have a shader in this 1336 * case). If there is no texs array, but there is a color array, then each 1337 * color is interpolated across its corresponding triangle in a gradient. If 1338 * both texs and colors arrays are present, then they behave as before, but 1339 * the resulting color at each pixels is the result of multiplying the 1340 * colors from the shader and the color-gradient together. The indices array 1341 * is optional, but if it is present, then it is used to specify the index 1342 * of each triangle, rather than just walking through the arrays in order. 1343 * 1344 * @param mode How to interpret the array of vertices 1345 * @param vertexCount The number of values in the vertices array (and 1346 * corresponding texs and colors arrays if non-null). Each logical 1347 * vertex is two values (x, y), vertexCount must be a multiple of 2. 1348 * @param verts Array of vertices for the mesh 1349 * @param vertOffset Number of values in the verts to skip before drawing. 1350 * @param texs May be null. If not null, specifies the coordinates to sample 1351 * into the current shader (e.g. bitmap tile or gradient) 1352 * @param texOffset Number of values in texs to skip before drawing. 1353 * @param colors May be null. If not null, specifies a color for each 1354 * vertex, to be interpolated across the triangle. 1355 * @param colorOffset Number of values in colors to skip before drawing. 1356 * @param indices If not null, array of indices to reference into the 1357 * vertex (texs, colors) array. 1358 * @param indexCount number of entries in the indices array (if not null). 1359 * @param paint Specifies the shader to use if the texs array is non-null. 1360 */ 1361 public void drawVertices(VertexMode mode, int vertexCount, float[] verts, int vertOffset, 1362 float[] texs, int texOffset, int[] colors, int colorOffset, 1363 short[] indices, int indexOffset, int indexCount, Paint paint) { 1364 checkRange(verts.length, vertOffset, vertexCount); 1365 if (texs != null) { 1366 checkRange(texs.length, texOffset, vertexCount); 1367 } 1368 if (colors != null) { 1369 checkRange(colors.length, colorOffset, vertexCount / 2); 1370 } 1371 if (indices != null) { 1372 checkRange(indices.length, indexOffset, indexCount); 1373 } 1374 nativeDrawVertices(mNativeCanvas, mode.nativeInt, vertexCount, verts, 1375 vertOffset, texs, texOffset, colors, colorOffset, 1376 indices, indexOffset, indexCount, paint.mNativePaint); 1377 } 1378 1379 /** 1380 * Draw the text, with origin at (x,y), using the specified paint. The 1381 * origin is interpreted based on the Align setting in the paint. 1382 * 1383 * @param text The text to be drawn 1384 * @param x The x-coordinate of the origin of the text being drawn 1385 * @param y The y-coordinate of the origin of the text being drawn 1386 * @param paint The paint used for the text (e.g. color, size, style) 1387 */ 1388 public void drawText(char[] text, int index, int count, float x, float y, Paint paint) { 1389 if ((index | count | (index + count) | 1390 (text.length - index - count)) < 0) { 1391 throw new IndexOutOfBoundsException(); 1392 } 1393 native_drawText(mNativeCanvas, text, index, count, x, y, paint.mBidiFlags, 1394 paint.mNativePaint); 1395 } 1396 1397 /** 1398 * Draw the text, with origin at (x,y), using the specified paint. The 1399 * origin is interpreted based on the Align setting in the paint. 1400 * 1401 * @param text The text to be drawn 1402 * @param x The x-coordinate of the origin of the text being drawn 1403 * @param y The y-coordinate of the origin of the text being drawn 1404 * @param paint The paint used for the text (e.g. color, size, style) 1405 */ 1406 public void drawText(String text, float x, float y, Paint paint) { 1407 native_drawText(mNativeCanvas, text, 0, text.length(), x, y, paint.mBidiFlags, 1408 paint.mNativePaint); 1409 } 1410 1411 /** 1412 * Draw the text, with origin at (x,y), using the specified paint. 1413 * The origin is interpreted based on the Align setting in the paint. 1414 * 1415 * @param text The text to be drawn 1416 * @param start The index of the first character in text to draw 1417 * @param end (end - 1) is the index of the last character in text to draw 1418 * @param x The x-coordinate of the origin of the text being drawn 1419 * @param y The y-coordinate of the origin of the text being drawn 1420 * @param paint The paint used for the text (e.g. color, size, style) 1421 */ 1422 public void drawText(String text, int start, int end, float x, float y, Paint paint) { 1423 if ((start | end | (end - start) | (text.length() - end)) < 0) { 1424 throw new IndexOutOfBoundsException(); 1425 } 1426 native_drawText(mNativeCanvas, text, start, end, x, y, paint.mBidiFlags, 1427 paint.mNativePaint); 1428 } 1429 1430 /** 1431 * Draw the specified range of text, specified by start/end, with its 1432 * origin at (x,y), in the specified Paint. The origin is interpreted 1433 * based on the Align setting in the Paint. 1434 * 1435 * @param text The text to be drawn 1436 * @param start The index of the first character in text to draw 1437 * @param end (end - 1) is the index of the last character in text 1438 * to draw 1439 * @param x The x-coordinate of origin for where to draw the text 1440 * @param y The y-coordinate of origin for where to draw the text 1441 * @param paint The paint used for the text (e.g. color, size, style) 1442 */ 1443 public void drawText(CharSequence text, int start, int end, float x, float y, Paint paint) { 1444 if (text instanceof String || text instanceof SpannedString || 1445 text instanceof SpannableString) { 1446 native_drawText(mNativeCanvas, text.toString(), start, end, x, y, 1447 paint.mBidiFlags, paint.mNativePaint); 1448 } else if (text instanceof GraphicsOperations) { 1449 ((GraphicsOperations) text).drawText(this, start, end, x, y, 1450 paint); 1451 } else { 1452 char[] buf = TemporaryBuffer.obtain(end - start); 1453 TextUtils.getChars(text, start, end, buf, 0); 1454 native_drawText(mNativeCanvas, buf, 0, end - start, x, y, 1455 paint.mBidiFlags, paint.mNativePaint); 1456 TemporaryBuffer.recycle(buf); 1457 } 1458 } 1459 1460 /** 1461 * Render a run of all LTR or all RTL text, with shaping. This does not run 1462 * bidi on the provided text, but renders it as a uniform right-to-left or 1463 * left-to-right run, as indicated by dir. Alignment of the text is as 1464 * determined by the Paint's TextAlign value. 1465 * 1466 * @param text the text to render 1467 * @param index the start of the text to render 1468 * @param count the count of chars to render 1469 * @param contextIndex the start of the context for shaping. Must be 1470 * no greater than index. 1471 * @param contextCount the number of characters in the context for shaping. 1472 * ContexIndex + contextCount must be no less than index 1473 * + count. 1474 * @param x the x position at which to draw the text 1475 * @param y the y position at which to draw the text 1476 * @param dir the run direction, either {@link #DIRECTION_LTR} or 1477 * {@link #DIRECTION_RTL}. 1478 * @param paint the paint 1479 * @hide 1480 */ 1481 public void drawTextRun(char[] text, int index, int count, int contextIndex, int contextCount, 1482 float x, float y, int dir, Paint paint) { 1483 1484 if (text == null) { 1485 throw new NullPointerException("text is null"); 1486 } 1487 if (paint == null) { 1488 throw new NullPointerException("paint is null"); 1489 } 1490 if ((index | count | text.length - index - count) < 0) { 1491 throw new IndexOutOfBoundsException(); 1492 } 1493 if (dir != DIRECTION_LTR && dir != DIRECTION_RTL) { 1494 throw new IllegalArgumentException("unknown dir: " + dir); 1495 } 1496 1497 native_drawTextRun(mNativeCanvas, text, index, count, 1498 contextIndex, contextCount, x, y, dir, paint.mNativePaint); 1499 } 1500 1501 /** 1502 * Render a run of all LTR or all RTL text, with shaping. This does not run 1503 * bidi on the provided text, but renders it as a uniform right-to-left or 1504 * left-to-right run, as indicated by dir. Alignment of the text is as 1505 * determined by the Paint's TextAlign value. 1506 * 1507 * @param text the text to render 1508 * @param start the start of the text to render. Data before this position 1509 * can be used for shaping context. 1510 * @param end the end of the text to render. Data at or after this 1511 * position can be used for shaping context. 1512 * @param x the x position at which to draw the text 1513 * @param y the y position at which to draw the text 1514 * @param dir the run direction, either 0 for LTR or 1 for RTL. 1515 * @param paint the paint 1516 * @hide 1517 */ 1518 public void drawTextRun(CharSequence text, int start, int end, int contextStart, int contextEnd, 1519 float x, float y, int dir, Paint paint) { 1520 1521 if (text == null) { 1522 throw new NullPointerException("text is null"); 1523 } 1524 if (paint == null) { 1525 throw new NullPointerException("paint is null"); 1526 } 1527 if ((start | end | end - start | text.length() - end) < 0) { 1528 throw new IndexOutOfBoundsException(); 1529 } 1530 1531 int flags = dir == 0 ? 0 : 1; 1532 1533 if (text instanceof String || text instanceof SpannedString || 1534 text instanceof SpannableString) { 1535 native_drawTextRun(mNativeCanvas, text.toString(), start, end, 1536 contextStart, contextEnd, x, y, flags, paint.mNativePaint); 1537 } else if (text instanceof GraphicsOperations) { 1538 ((GraphicsOperations) text).drawTextRun(this, start, end, 1539 contextStart, contextEnd, x, y, flags, paint); 1540 } else { 1541 int contextLen = contextEnd - contextStart; 1542 int len = end - start; 1543 char[] buf = TemporaryBuffer.obtain(contextLen); 1544 TextUtils.getChars(text, contextStart, contextEnd, buf, 0); 1545 native_drawTextRun(mNativeCanvas, buf, start - contextStart, len, 1546 0, contextLen, x, y, flags, paint.mNativePaint); 1547 TemporaryBuffer.recycle(buf); 1548 } 1549 } 1550 1551 /** 1552 * Draw the text in the array, with each character's origin specified by 1553 * the pos array. 1554 * 1555 * This method does not support glyph composition and decomposition and 1556 * should therefore not be used to render complex scripts. 1557 * 1558 * @param text The text to be drawn 1559 * @param index The index of the first character to draw 1560 * @param count The number of characters to draw, starting from index. 1561 * @param pos Array of [x,y] positions, used to position each 1562 * character 1563 * @param paint The paint used for the text (e.g. color, size, style) 1564 */ 1565 @Deprecated 1566 public void drawPosText(char[] text, int index, int count, float[] pos, Paint paint) { 1567 if (index < 0 || index + count > text.length || count*2 > pos.length) { 1568 throw new IndexOutOfBoundsException(); 1569 } 1570 native_drawPosText(mNativeCanvas, text, index, count, pos, 1571 paint.mNativePaint); 1572 } 1573 1574 /** 1575 * Draw the text in the array, with each character's origin specified by 1576 * the pos array. 1577 * 1578 * This method does not support glyph composition and decomposition and 1579 * should therefore not be used to render complex scripts. 1580 * 1581 * @param text The text to be drawn 1582 * @param pos Array of [x,y] positions, used to position each character 1583 * @param paint The paint used for the text (e.g. color, size, style) 1584 */ 1585 @Deprecated 1586 public void drawPosText(String text, float[] pos, Paint paint) { 1587 if (text.length()*2 > pos.length) { 1588 throw new ArrayIndexOutOfBoundsException(); 1589 } 1590 native_drawPosText(mNativeCanvas, text, pos, paint.mNativePaint); 1591 } 1592 1593 /** 1594 * Draw the text, with origin at (x,y), using the specified paint, along 1595 * the specified path. The paint's Align setting determins where along the 1596 * path to start the text. 1597 * 1598 * @param text The text to be drawn 1599 * @param path The path the text should follow for its baseline 1600 * @param hOffset The distance along the path to add to the text's 1601 * starting position 1602 * @param vOffset The distance above(-) or below(+) the path to position 1603 * the text 1604 * @param paint The paint used for the text (e.g. color, size, style) 1605 */ 1606 public void drawTextOnPath(char[] text, int index, int count, Path path, 1607 float hOffset, float vOffset, Paint paint) { 1608 if (index < 0 || index + count > text.length) { 1609 throw new ArrayIndexOutOfBoundsException(); 1610 } 1611 native_drawTextOnPath(mNativeCanvas, text, index, count, 1612 path.ni(), hOffset, vOffset, 1613 paint.mBidiFlags, paint.mNativePaint); 1614 } 1615 1616 /** 1617 * Draw the text, with origin at (x,y), using the specified paint, along 1618 * the specified path. The paint's Align setting determins where along the 1619 * path to start the text. 1620 * 1621 * @param text The text to be drawn 1622 * @param path The path the text should follow for its baseline 1623 * @param hOffset The distance along the path to add to the text's 1624 * starting position 1625 * @param vOffset The distance above(-) or below(+) the path to position 1626 * the text 1627 * @param paint The paint used for the text (e.g. color, size, style) 1628 */ 1629 public void drawTextOnPath(String text, Path path, float hOffset, float vOffset, Paint paint) { 1630 if (text.length() > 0) { 1631 native_drawTextOnPath(mNativeCanvas, text, path.ni(), hOffset, vOffset, 1632 paint.mBidiFlags, paint.mNativePaint); 1633 } 1634 } 1635 1636 /** 1637 * Save the canvas state, draw the picture, and restore the canvas state. 1638 * This differs from picture.draw(canvas), which does not perform any 1639 * save/restore. 1640 * 1641 * <p> 1642 * <strong>Note:</strong> This forces the picture to internally call 1643 * {@link Picture#endRecording} in order to prepare for playback. 1644 * 1645 * @param picture The picture to be drawn 1646 */ 1647 public void drawPicture(Picture picture) { 1648 picture.endRecording(); 1649 int restoreCount = save(); 1650 picture.draw(this); 1651 restoreToCount(restoreCount); 1652 } 1653 1654 /** 1655 * Draw the picture, stretched to fit into the dst rectangle. 1656 */ 1657 public void drawPicture(Picture picture, RectF dst) { 1658 save(); 1659 translate(dst.left, dst.top); 1660 if (picture.getWidth() > 0 && picture.getHeight() > 0) { 1661 scale(dst.width() / picture.getWidth(), dst.height() / picture.getHeight()); 1662 } 1663 drawPicture(picture); 1664 restore(); 1665 } 1666 1667 /** 1668 * Draw the picture, stretched to fit into the dst rectangle. 1669 */ 1670 public void drawPicture(Picture picture, Rect dst) { 1671 save(); 1672 translate(dst.left, dst.top); 1673 if (picture.getWidth() > 0 && picture.getHeight() > 0) { 1674 scale((float) dst.width() / picture.getWidth(), 1675 (float) dst.height() / picture.getHeight()); 1676 } 1677 drawPicture(picture); 1678 restore(); 1679 } 1680 1681 /** 1682 * Releases the resources associated with this canvas. 1683 * 1684 * @hide 1685 */ 1686 public void release() { 1687 mFinalizer.dispose(); 1688 } 1689 1690 /** 1691 * Free up as much memory as possible from private caches (e.g. fonts, images) 1692 * 1693 * @hide 1694 */ 1695 public static native void freeCaches(); 1696 1697 /** 1698 * Free up text layout caches 1699 * 1700 * @hide 1701 */ 1702 public static native void freeTextLayoutCaches(); 1703 1704 private static native int initRaster(int nativeBitmapOrZero); 1705 private static native void copyNativeCanvasState(int srcCanvas, int dstCanvas); 1706 private static native int native_saveLayer(int nativeCanvas, RectF bounds, 1707 int paint, int layerFlags); 1708 private static native int native_saveLayer(int nativeCanvas, float l, 1709 float t, float r, float b, 1710 int paint, int layerFlags); 1711 private static native int native_saveLayerAlpha(int nativeCanvas, 1712 RectF bounds, int alpha, 1713 int layerFlags); 1714 private static native int native_saveLayerAlpha(int nativeCanvas, float l, 1715 float t, float r, float b, 1716 int alpha, int layerFlags); 1717 1718 private static native void native_concat(int nCanvas, int nMatrix); 1719 private static native void native_setMatrix(int nCanvas, int nMatrix); 1720 private static native boolean native_clipRect(int nCanvas, 1721 float left, float top, 1722 float right, float bottom, 1723 int regionOp); 1724 private static native boolean native_clipPath(int nativeCanvas, 1725 int nativePath, 1726 int regionOp); 1727 private static native boolean native_clipRegion(int nativeCanvas, 1728 int nativeRegion, 1729 int regionOp); 1730 private static native void nativeSetDrawFilter(int nativeCanvas, 1731 int nativeFilter); 1732 private static native boolean native_getClipBounds(int nativeCanvas, 1733 Rect bounds); 1734 private static native void native_getCTM(int canvas, int matrix); 1735 private static native boolean native_quickReject(int nativeCanvas, 1736 RectF rect); 1737 private static native boolean native_quickReject(int nativeCanvas, 1738 int path); 1739 private static native boolean native_quickReject(int nativeCanvas, 1740 float left, float top, 1741 float right, float bottom); 1742 private static native void native_drawRGB(int nativeCanvas, int r, int g, 1743 int b); 1744 private static native void native_drawARGB(int nativeCanvas, int a, int r, 1745 int g, int b); 1746 private static native void native_drawColor(int nativeCanvas, int color); 1747 private static native void native_drawColor(int nativeCanvas, int color, 1748 int mode); 1749 private static native void native_drawPaint(int nativeCanvas, int paint); 1750 private static native void native_drawLine(int nativeCanvas, float startX, 1751 float startY, float stopX, 1752 float stopY, int paint); 1753 private static native void native_drawRect(int nativeCanvas, RectF rect, 1754 int paint); 1755 private static native void native_drawRect(int nativeCanvas, float left, 1756 float top, float right, 1757 float bottom, int paint); 1758 private static native void native_drawOval(int nativeCanvas, RectF oval, 1759 int paint); 1760 private static native void native_drawCircle(int nativeCanvas, float cx, 1761 float cy, float radius, 1762 int paint); 1763 private static native void native_drawArc(int nativeCanvas, RectF oval, 1764 float startAngle, float sweep, 1765 boolean useCenter, int paint); 1766 private static native void native_drawRoundRect(int nativeCanvas, 1767 RectF rect, float rx, 1768 float ry, int paint); 1769 private static native void native_drawPath(int nativeCanvas, int path, 1770 int paint); 1771 private native void native_drawBitmap(int nativeCanvas, int bitmap, 1772 float left, float top, 1773 int nativePaintOrZero, 1774 int canvasDensity, 1775 int screenDensity, 1776 int bitmapDensity); 1777 private native void native_drawBitmap(int nativeCanvas, int bitmap, 1778 Rect src, RectF dst, 1779 int nativePaintOrZero, 1780 int screenDensity, 1781 int bitmapDensity); 1782 private static native void native_drawBitmap(int nativeCanvas, int bitmap, 1783 Rect src, Rect dst, 1784 int nativePaintOrZero, 1785 int screenDensity, 1786 int bitmapDensity); 1787 private static native void native_drawBitmap(int nativeCanvas, int[] colors, 1788 int offset, int stride, float x, 1789 float y, int width, int height, 1790 boolean hasAlpha, 1791 int nativePaintOrZero); 1792 private static native void nativeDrawBitmapMatrix(int nCanvas, int nBitmap, 1793 int nMatrix, int nPaint); 1794 private static native void nativeDrawBitmapMesh(int nCanvas, int nBitmap, 1795 int meshWidth, int meshHeight, 1796 float[] verts, int vertOffset, 1797 int[] colors, int colorOffset, int nPaint); 1798 private static native void nativeDrawVertices(int nCanvas, int mode, int n, 1799 float[] verts, int vertOffset, float[] texs, int texOffset, 1800 int[] colors, int colorOffset, short[] indices, 1801 int indexOffset, int indexCount, int nPaint); 1802 1803 private static native void native_drawText(int nativeCanvas, char[] text, 1804 int index, int count, float x, 1805 float y, int flags, int paint); 1806 private static native void native_drawText(int nativeCanvas, String text, 1807 int start, int end, float x, 1808 float y, int flags, int paint); 1809 1810 private static native void native_drawTextRun(int nativeCanvas, String text, 1811 int start, int end, int contextStart, int contextEnd, 1812 float x, float y, int flags, int paint); 1813 1814 private static native void native_drawTextRun(int nativeCanvas, char[] text, 1815 int start, int count, int contextStart, int contextCount, 1816 float x, float y, int flags, int paint); 1817 1818 private static native void native_drawPosText(int nativeCanvas, 1819 char[] text, int index, 1820 int count, float[] pos, 1821 int paint); 1822 private static native void native_drawPosText(int nativeCanvas, 1823 String text, float[] pos, 1824 int paint); 1825 private static native void native_drawTextOnPath(int nativeCanvas, 1826 char[] text, int index, 1827 int count, int path, 1828 float hOffset, 1829 float vOffset, int bidiFlags, 1830 int paint); 1831 private static native void native_drawTextOnPath(int nativeCanvas, 1832 String text, int path, 1833 float hOffset, 1834 float vOffset, 1835 int flags, int paint); 1836 private static native void finalizer(int nativeCanvas); 1837} 1838