Canvas.java revision ce0537b80087a6225273040a987414b1dd081aa0
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 */ 33public class Canvas { 34 // assigned in constructors, freed in finalizer 35 final int mNativeCanvas; 36 37 /* Our native canvas can be either a raster, gl, or picture canvas. 38 If we are raster, then mGL will be null, and mBitmap may or may not be 39 present (our default constructor creates a raster canvas but no 40 java-bitmap is). If we are a gl-based, then mBitmap will be null, and 41 mGL will not be null. Thus both cannot be non-null, but its possible 42 for both to be null. 43 */ 44 private Bitmap mBitmap; // if not null, mGL must be null 45 private GL mGL; // if not null, mBitmap must be null 46 47 // optional field set by the caller 48 private DrawFilter mDrawFilter; 49 50 /** 51 * @hide 52 */ 53 protected int mDensity = Bitmap.DENSITY_NONE; 54 55 /** 56 * Used to determine when compatibility scaling is in effect. 57 * 58 * @hide 59 */ 60 protected int mScreenDensity = Bitmap.DENSITY_NONE; 61 62 // Used by native code 63 @SuppressWarnings({"UnusedDeclaration"}) 64 private int mSurfaceFormat; 65 66 /** 67 * Flag for drawTextRun indicating left-to-right run direction. 68 * @hide 69 */ 70 public static final int DIRECTION_LTR = 0; 71 72 /** 73 * Flag for drawTextRun indicating right-to-left run direction. 74 * @hide 75 */ 76 public static final int DIRECTION_RTL = 1; 77 78 /** 79 * Construct an empty raster canvas. Use setBitmap() to specify a bitmap to 80 * draw into. The initial target density is {@link Bitmap#DENSITY_NONE}; 81 * this will typically be replaced when a target bitmap is set for the 82 * canvas. 83 */ 84 public Canvas() { 85 // 0 means no native bitmap 86 mNativeCanvas = initRaster(0); 87 } 88 89 /** 90 * Construct a canvas with the specified bitmap to draw into. The bitmap 91 * must be mutable. 92 * 93 * <p>The initial target density of the canvas is the same as the given 94 * bitmap's density. 95 * 96 * @param bitmap Specifies a mutable bitmap for the canvas to draw into. 97 */ 98 public Canvas(Bitmap bitmap) { 99 if (!bitmap.isMutable()) { 100 throw new IllegalStateException( 101 "Immutable bitmap passed to Canvas constructor"); 102 } 103 throwIfRecycled(bitmap); 104 mNativeCanvas = initRaster(bitmap.ni()); 105 mBitmap = bitmap; 106 mDensity = bitmap.mDensity; 107 } 108 109 /*package*/ Canvas(int nativeCanvas) { 110 if (nativeCanvas == 0) { 111 throw new IllegalStateException(); 112 } 113 mNativeCanvas = nativeCanvas; 114 mDensity = Bitmap.getDefaultDensity(); 115 } 116 117 /** 118 * Construct a canvas with the specified gl context. All drawing through 119 * this canvas will be redirected to OpenGL. Note: some features may not 120 * be supported in this mode (e.g. some GL implementations may not support 121 * antialiasing or certain effects like ColorMatrix or certain Xfermodes). 122 * However, no exception will be thrown in those cases. 123 * 124 * <p>The initial target density of the canvas is the same as the initial 125 * density of bitmaps as per {@link Bitmap#getDensity() Bitmap.getDensity()}. 126 * 127 * @deprecated This constructor is not supported and should not be invoked. 128 */ 129 public Canvas(GL gl) { 130 mNativeCanvas = initGL(); 131 mGL = gl; 132 mDensity = Bitmap.getDefaultDensity(); 133 } 134 135 /** 136 * Indicates whether this Canvas uses hardware acceleration. 137 * 138 * Note that this method does not define what type of hardware acceleration 139 * may or may not be used. 140 * 141 * @return True if drawing operations are hardware accelerated, 142 * false otherwise. 143 */ 144 public boolean isHardwareAccelerated() { 145 return mGL != null; 146 } 147 148 /** 149 * Return the GL object associated with this canvas, or null if it is not 150 * backed by GL. 151 * 152 * @deprecated This method is not supported and should not be invoked. 153 */ 154 public GL getGL() { 155 return mGL; 156 } 157 158 /** 159 * Call this to free up OpenGL resources that may be cached or allocated 160 * on behalf of the Canvas. Any subsequent drawing with a GL-backed Canvas 161 * will have to recreate those resources. 162 * 163 * @deprecated This method is not supported and should not be invoked. 164 */ 165 public static void freeGlCaches() { 166 freeCaches(); 167 } 168 169 /** 170 * Specify a bitmap for the canvas to draw into. As a side-effect, also 171 * updates the canvas's target density to match that of the bitmap. 172 * 173 * @param bitmap Specifies a mutable bitmap for the canvas to draw into. 174 * 175 * @see #setDensity(int) 176 * @see #getDensity() 177 */ 178 public void setBitmap(Bitmap bitmap) { 179 if (!bitmap.isMutable()) { 180 throw new IllegalStateException(); 181 } 182 if (mGL != null) { 183 throw new RuntimeException("Can't set a bitmap device on a GL canvas"); 184 } 185 throwIfRecycled(bitmap); 186 187 native_setBitmap(mNativeCanvas, bitmap.ni()); 188 mBitmap = bitmap; 189 mDensity = bitmap.mDensity; 190 } 191 192 /** 193 * Set the viewport dimensions if this canvas is GL based. If it is not, 194 * this method is ignored and no exception is thrown. 195 * 196 * @param width The width of the viewport 197 * @param height The height of the viewport 198 * 199 * @deprecated This method is not supported and should not be invoked. 200 */ 201 public void setViewport(int width, int height) { 202 if (mGL != null) { 203 nativeSetViewport(mNativeCanvas, width, height); 204 } 205 } 206 207 /** 208 * Return true if the device that the current layer draws into is opaque 209 * (i.e. does not support per-pixel alpha). 210 * 211 * @return true if the device that the current layer draws into is opaque 212 */ 213 public native boolean isOpaque(); 214 215 /** 216 * Returns the width of the current drawing layer 217 * 218 * @return the width of the current drawing layer 219 */ 220 public native int getWidth(); 221 222 /** 223 * Returns the height of the current drawing layer 224 * 225 * @return the height of the current drawing layer 226 */ 227 public native int getHeight(); 228 229 /** 230 * <p>Returns the target density of the canvas. The default density is 231 * derived from the density of its backing bitmap, or 232 * {@link Bitmap#DENSITY_NONE} if there is not one.</p> 233 * 234 * @return Returns the current target density of the canvas, which is used 235 * to determine the scaling factor when drawing a bitmap into it. 236 * 237 * @see #setDensity(int) 238 * @see Bitmap#getDensity() 239 */ 240 public int getDensity() { 241 return mDensity; 242 } 243 244 /** 245 * <p>Specifies the density for this Canvas' backing bitmap. This modifies 246 * the target density of the canvas itself, as well as the density of its 247 * backing bitmap via {@link Bitmap#setDensity(int) Bitmap.setDensity(int)}. 248 * 249 * @param density The new target density of the canvas, which is used 250 * to determine the scaling factor when drawing a bitmap into it. Use 251 * {@link Bitmap#DENSITY_NONE} to disable bitmap scaling. 252 * 253 * @see #getDensity() 254 * @see Bitmap#setDensity(int) 255 */ 256 public void setDensity(int density) { 257 if (mBitmap != null) { 258 mBitmap.setDensity(density); 259 } 260 mDensity = density; 261 } 262 263 /** @hide */ 264 public void setScreenDensity(int density) { 265 mScreenDensity = density; 266 } 267 268 // the SAVE_FLAG constants must match their native equivalents 269 270 /** restore the current matrix when restore() is called */ 271 public static final int MATRIX_SAVE_FLAG = 0x01; 272 /** restore the current clip when restore() is called */ 273 public static final int CLIP_SAVE_FLAG = 0x02; 274 /** the layer needs to per-pixel alpha */ 275 public static final int HAS_ALPHA_LAYER_SAVE_FLAG = 0x04; 276 /** the layer needs to 8-bits per color component */ 277 public static final int FULL_COLOR_LAYER_SAVE_FLAG = 0x08; 278 /** clip against the layer's bounds */ 279 public static final int CLIP_TO_LAYER_SAVE_FLAG = 0x10; 280 /** restore everything when restore() is called */ 281 public static final int ALL_SAVE_FLAG = 0x1F; 282 283 /** 284 * Saves the current matrix and clip onto a private stack. Subsequent 285 * calls to translate,scale,rotate,skew,concat or clipRect,clipPath 286 * will all operate as usual, but when the balancing call to restore() 287 * is made, those calls will be forgotten, and the settings that existed 288 * before the save() will be reinstated. 289 * 290 * @return The value to pass to restoreToCount() to balance this save() 291 */ 292 public native int save(); 293 294 /** 295 * Based on saveFlags, can save the current matrix and clip onto a private 296 * stack. Subsequent calls to translate,scale,rotate,skew,concat or 297 * clipRect,clipPath will all operate as usual, but when the balancing 298 * call to restore() is made, those calls will be forgotten, and the 299 * settings that existed before the save() will be reinstated. 300 * 301 * @param saveFlags flag bits that specify which parts of the Canvas state 302 * to save/restore 303 * @return The value to pass to restoreToCount() to balance this save() 304 */ 305 public native int save(int saveFlags); 306 307 /** 308 * This behaves the same as save(), but in addition it allocates an 309 * offscreen bitmap. All drawing calls are directed there, and only when 310 * the balancing call to restore() is made is that offscreen transfered to 311 * the canvas (or the previous layer). Subsequent calls to translate, 312 * scale, rotate, skew, concat or clipRect, clipPath all operate on this 313 * copy. When the balancing call to restore() is made, this copy is 314 * deleted and the previous matrix/clip state is restored. 315 * 316 * @param bounds May be null. The maximum size the offscreen bitmap 317 * needs to be (in local coordinates) 318 * @param paint This is copied, and is applied to the offscreen when 319 * restore() is called. 320 * @param saveFlags see _SAVE_FLAG constants 321 * @return value to pass to restoreToCount() to balance this save() 322 */ 323 public int saveLayer(RectF bounds, Paint paint, int saveFlags) { 324 return native_saveLayer(mNativeCanvas, bounds, 325 paint != null ? paint.mNativePaint : 0, 326 saveFlags); 327 } 328 329 /** 330 * Helper version of saveLayer() that takes 4 values rather than a RectF. 331 */ 332 public int saveLayer(float left, float top, float right, float bottom, 333 Paint paint, int saveFlags) { 334 return native_saveLayer(mNativeCanvas, left, top, right, bottom, 335 paint != null ? paint.mNativePaint : 0, 336 saveFlags); 337 } 338 339 /** 340 * This behaves the same as save(), but in addition it allocates an 341 * offscreen bitmap. All drawing calls are directed there, and only when 342 * the balancing call to restore() is made is that offscreen transfered to 343 * the canvas (or the previous layer). Subsequent calls to translate, 344 * scale, rotate, skew, concat or clipRect, clipPath all operate on this 345 * copy. When the balancing call to restore() is made, this copy is 346 * deleted and the previous matrix/clip state is restored. 347 * 348 * @param bounds The maximum size the offscreen bitmap needs to be 349 * (in local coordinates) 350 * @param alpha The alpha to apply to the offscreen when when it is 351 drawn during restore() 352 * @param saveFlags see _SAVE_FLAG constants 353 * @return value to pass to restoreToCount() to balance this call 354 */ 355 public int saveLayerAlpha(RectF bounds, int alpha, int saveFlags) { 356 alpha = Math.min(255, Math.max(0, alpha)); 357 return native_saveLayerAlpha(mNativeCanvas, bounds, alpha, saveFlags); 358 } 359 360 /** 361 * Helper for saveLayerAlpha() that takes 4 values instead of a RectF. 362 */ 363 public int saveLayerAlpha(float left, float top, float right, float bottom, 364 int alpha, int saveFlags) { 365 return native_saveLayerAlpha(mNativeCanvas, left, top, right, bottom, 366 alpha, saveFlags); 367 } 368 369 /** 370 * This call balances a previous call to save(), and is used to remove all 371 * modifications to the matrix/clip state since the last save call. It is 372 * an error to call restore() more times than save() was called. 373 */ 374 public native void restore(); 375 376 /** 377 * Returns the number of matrix/clip states on the Canvas' private stack. 378 * This will equal # save() calls - # restore() calls. 379 */ 380 public native int getSaveCount(); 381 382 /** 383 * Efficient way to pop any calls to save() that happened after the save 384 * count reached saveCount. It is an error for saveCount to be less than 1. 385 * 386 * Example: 387 * int count = canvas.save(); 388 * ... // more calls potentially to save() 389 * canvas.restoreToCount(count); 390 * // now the canvas is back in the same state it was before the initial 391 * // call to save(). 392 * 393 * @param saveCount The save level to restore to. 394 */ 395 public native void restoreToCount(int saveCount); 396 397 /** 398 * Preconcat the current matrix with the specified translation 399 * 400 * @param dx The distance to translate in X 401 * @param dy The distance to translate in Y 402 */ 403 public native void translate(float dx, float dy); 404 405 /** 406 * Preconcat the current matrix with the specified scale. 407 * 408 * @param sx The amount to scale in X 409 * @param sy The amount to scale in Y 410 */ 411 public native void scale(float sx, float sy); 412 413 /** 414 * Preconcat the current matrix with the specified scale. 415 * 416 * @param sx The amount to scale in X 417 * @param sy The amount to scale in Y 418 * @param px The x-coord for the pivot point (unchanged by the rotation) 419 * @param py The y-coord for the pivot point (unchanged by the rotation) 420 */ 421 public final void scale(float sx, float sy, float px, float py) { 422 translate(px, py); 423 scale(sx, sy); 424 translate(-px, -py); 425 } 426 427 /** 428 * Preconcat the current matrix with the specified rotation. 429 * 430 * @param degrees The amount to rotate, in degrees 431 */ 432 public native void rotate(float degrees); 433 434 /** 435 * Preconcat the current matrix with the specified rotation. 436 * 437 * @param degrees The amount to rotate, in degrees 438 * @param px The x-coord for the pivot point (unchanged by the rotation) 439 * @param py The y-coord for the pivot point (unchanged by the rotation) 440 */ 441 public final void rotate(float degrees, float px, float py) { 442 translate(px, py); 443 rotate(degrees); 444 translate(-px, -py); 445 } 446 447 /** 448 * Preconcat the current matrix with the specified skew. 449 * 450 * @param sx The amount to skew in X 451 * @param sy The amount to skew in Y 452 */ 453 public native void skew(float sx, float sy); 454 455 /** 456 * Preconcat the current matrix with the specified matrix. 457 * 458 * @param matrix The matrix to preconcatenate with the current matrix 459 */ 460 public void concat(Matrix matrix) { 461 native_concat(mNativeCanvas, matrix.native_instance); 462 } 463 464 /** 465 * Completely replace the current matrix with the specified matrix. If the 466 * matrix parameter is null, then the current matrix is reset to identity. 467 * 468 * @param matrix The matrix to replace the current matrix with. If it is 469 * null, set the current matrix to identity. 470 */ 471 public void setMatrix(Matrix matrix) { 472 native_setMatrix(mNativeCanvas, 473 matrix == null ? 0 : matrix.native_instance); 474 } 475 476 /** 477 * Return, in ctm, the current transformation matrix. This does not alter 478 * the matrix in the canvas, but just returns a copy of it. 479 */ 480 public void getMatrix(Matrix ctm) { 481 native_getCTM(mNativeCanvas, ctm.native_instance); 482 } 483 484 /** 485 * Return a new matrix with a copy of the canvas' current transformation 486 * matrix. 487 */ 488 public final Matrix getMatrix() { 489 Matrix m = new Matrix(); 490 getMatrix(m); 491 return m; 492 } 493 494 /** 495 * Modify the current clip with the specified rectangle. 496 * 497 * @param rect The rect to intersect with the current clip 498 * @param op How the clip is modified 499 * @return true if the resulting clip is non-empty 500 */ 501 public boolean clipRect(RectF rect, Region.Op op) { 502 return native_clipRect(mNativeCanvas, 503 rect.left, rect.top, rect.right, rect.bottom, 504 op.nativeInt); 505 } 506 507 /** 508 * Modify the current clip with the specified rectangle, which is 509 * expressed in local coordinates. 510 * 511 * @param rect The rectangle to intersect with the current clip. 512 * @param op How the clip is modified 513 * @return true if the resulting clip is non-empty 514 */ 515 public boolean clipRect(Rect rect, Region.Op op) { 516 return native_clipRect(mNativeCanvas, 517 rect.left, rect.top, rect.right, rect.bottom, 518 op.nativeInt); 519 } 520 521 /** 522 * Intersect the current clip with the specified rectangle, which is 523 * expressed in local coordinates. 524 * 525 * @param rect The rectangle to intersect with the current clip. 526 * @return true if the resulting clip is non-empty 527 */ 528 public native boolean clipRect(RectF rect); 529 530 /** 531 * Intersect the current clip with the specified rectangle, which is 532 * expressed in local coordinates. 533 * 534 * @param rect The rectangle to intersect with the current clip. 535 * @return true if the resulting clip is non-empty 536 */ 537 public native boolean clipRect(Rect rect); 538 539 /** 540 * Modify the current clip with the specified rectangle, which is 541 * expressed in local coordinates. 542 * 543 * @param left The left side of the rectangle to intersect with the 544 * current clip 545 * @param top The top of the rectangle to intersect with the current 546 * clip 547 * @param right The right side of the rectangle to intersect with the 548 * current clip 549 * @param bottom The bottom of the rectangle to intersect with the current 550 * clip 551 * @param op How the clip is modified 552 * @return true if the resulting clip is non-empty 553 */ 554 public boolean clipRect(float left, float top, float right, float bottom, 555 Region.Op op) { 556 return native_clipRect(mNativeCanvas, left, top, right, bottom, 557 op.nativeInt); 558 } 559 560 /** 561 * Intersect the current clip with the specified rectangle, which is 562 * expressed in local coordinates. 563 * 564 * @param left The left side of the rectangle to intersect with the 565 * current clip 566 * @param top The top of the rectangle to intersect with the current clip 567 * @param right The right side of the rectangle to intersect with the 568 * current clip 569 * @param bottom The bottom of the rectangle to intersect with the current 570 * clip 571 * @return true if the resulting clip is non-empty 572 */ 573 public native boolean clipRect(float left, float top, 574 float right, float bottom); 575 576 /** 577 * Intersect the current clip with the specified rectangle, which is 578 * expressed in local coordinates. 579 * 580 * @param left The left side of the rectangle to intersect with the 581 * current clip 582 * @param top The top of the rectangle to intersect with the current clip 583 * @param right The right side of the rectangle to intersect with the 584 * current clip 585 * @param bottom The bottom of the rectangle to intersect with the current 586 * clip 587 * @return true if the resulting clip is non-empty 588 */ 589 public native boolean clipRect(int left, int top, 590 int right, int bottom); 591 592 /** 593 * Modify the current clip with the specified path. 594 * 595 * @param path The path to operate on the current clip 596 * @param op How the clip is modified 597 * @return true if the resulting is non-empty 598 */ 599 public boolean clipPath(Path path, Region.Op op) { 600 return native_clipPath(mNativeCanvas, path.ni(), op.nativeInt); 601 } 602 603 /** 604 * Intersect the current clip with the specified path. 605 * 606 * @param path The path to intersect with the current clip 607 * @return true if the resulting is non-empty 608 */ 609 public boolean clipPath(Path path) { 610 return clipPath(path, Region.Op.INTERSECT); 611 } 612 613 /** 614 * Modify the current clip with the specified region. Note that unlike 615 * clipRect() and clipPath() which transform their arguments by the 616 * current matrix, clipRegion() assumes its argument is already in the 617 * coordinate system of the current layer's bitmap, and so not 618 * transformation is performed. 619 * 620 * @param region The region to operate on the current clip, based on op 621 * @param op How the clip is modified 622 * @return true if the resulting is non-empty 623 */ 624 public boolean clipRegion(Region region, Region.Op op) { 625 return native_clipRegion(mNativeCanvas, region.ni(), op.nativeInt); 626 } 627 628 /** 629 * Intersect the current clip with the specified region. Note that unlike 630 * clipRect() and clipPath() which transform their arguments by the 631 * current matrix, clipRegion() assumes its argument is already in the 632 * coordinate system of the current layer's bitmap, and so not 633 * transformation is performed. 634 * 635 * @param region The region to operate on the current clip, based on op 636 * @return true if the resulting is non-empty 637 */ 638 public boolean clipRegion(Region region) { 639 return clipRegion(region, Region.Op.INTERSECT); 640 } 641 642 public DrawFilter getDrawFilter() { 643 return mDrawFilter; 644 } 645 646 public void setDrawFilter(DrawFilter filter) { 647 int nativeFilter = 0; 648 if (filter != null) { 649 nativeFilter = filter.mNativeInt; 650 } 651 mDrawFilter = filter; 652 nativeSetDrawFilter(mNativeCanvas, nativeFilter); 653 } 654 655 public enum EdgeType { 656 BW(0), //!< treat edges by just rounding to nearest pixel boundary 657 AA(1); //!< treat edges by rounding-out, since they may be antialiased 658 659 EdgeType(int nativeInt) { 660 this.nativeInt = nativeInt; 661 } 662 663 /** 664 * @hide 665 */ 666 public final int nativeInt; 667 } 668 669 /** 670 * Return true if the specified rectangle, after being transformed by the 671 * current matrix, would lie completely outside of the current clip. Call 672 * this to check if an area you intend to draw into is clipped out (and 673 * therefore you can skip making the draw calls). 674 * 675 * @param rect the rect to compare with the current clip 676 * @param type specifies how to treat the edges (BW or antialiased) 677 * @return true if the rect (transformed by the canvas' matrix) 678 * does not intersect with the canvas' clip 679 */ 680 public boolean quickReject(RectF rect, EdgeType type) { 681 return native_quickReject(mNativeCanvas, rect, type.nativeInt); 682 } 683 684 /** 685 * Return true if the specified path, after being transformed by the 686 * current matrix, would lie completely outside of the current clip. Call 687 * this to check if an area you intend to draw into is clipped out (and 688 * therefore you can skip making the draw calls). Note: for speed it may 689 * return false even if the path itself might not intersect the clip 690 * (i.e. the bounds of the path intersects, but the path does not). 691 * 692 * @param path The path to compare with the current clip 693 * @param type true if the path should be considered antialiased, 694 * since that means it may 695 * affect a larger area (more pixels) than 696 * non-antialiased. 697 * @return true if the path (transformed by the canvas' matrix) 698 * does not intersect with the canvas' clip 699 */ 700 public boolean quickReject(Path path, EdgeType type) { 701 return native_quickReject(mNativeCanvas, path.ni(), type.nativeInt); 702 } 703 704 /** 705 * Return true if the specified rectangle, after being transformed by the 706 * current matrix, would lie completely outside of the current clip. Call 707 * this to check if an area you intend to draw into is clipped out (and 708 * therefore you can skip making the draw calls). 709 * 710 * @param left The left side of the rectangle to compare with the 711 * current clip 712 * @param top The top of the rectangle to compare with the current 713 * clip 714 * @param right The right side of the rectangle to compare with the 715 * current clip 716 * @param bottom The bottom of the rectangle to compare with the 717 * current clip 718 * @param type true if the rect should be considered antialiased, 719 * since that means it may affect a larger area (more 720 * pixels) than non-antialiased. 721 * @return true if the rect (transformed by the canvas' matrix) 722 * does not intersect with the canvas' clip 723 */ 724 public boolean quickReject(float left, float top, float right, float bottom, 725 EdgeType type) { 726 return native_quickReject(mNativeCanvas, left, top, right, bottom, 727 type.nativeInt); 728 } 729 730 /** 731 * Retrieve the clip bounds, returning true if they are non-empty. 732 * 733 * @param bounds Return the clip bounds here. If it is null, ignore it but 734 * still return true if the current clip is non-empty. 735 * @return true if the current clip is non-empty. 736 */ 737 public boolean getClipBounds(Rect bounds) { 738 return native_getClipBounds(mNativeCanvas, bounds); 739 } 740 741 /** 742 * Retrieve the clip bounds. 743 * 744 * @return the clip bounds, or [0, 0, 0, 0] if the clip is empty. 745 */ 746 public final Rect getClipBounds() { 747 Rect r = new Rect(); 748 getClipBounds(r); 749 return r; 750 } 751 752 /** 753 * Fill the entire canvas' bitmap (restricted to the current clip) with the 754 * specified RGB color, using srcover porterduff mode. 755 * 756 * @param r red component (0..255) of the color to draw onto the canvas 757 * @param g green component (0..255) of the color to draw onto the canvas 758 * @param b blue component (0..255) of the color to draw onto the canvas 759 */ 760 public void drawRGB(int r, int g, int b) { 761 native_drawRGB(mNativeCanvas, r, g, b); 762 } 763 764 /** 765 * Fill the entire canvas' bitmap (restricted to the current clip) with the 766 * specified ARGB color, using srcover porterduff mode. 767 * 768 * @param a alpha component (0..255) of the color to draw onto the canvas 769 * @param r red component (0..255) of the color to draw onto the canvas 770 * @param g green component (0..255) of the color to draw onto the canvas 771 * @param b blue component (0..255) of the color to draw onto the canvas 772 */ 773 public void drawARGB(int a, int r, int g, int b) { 774 native_drawARGB(mNativeCanvas, a, r, g, b); 775 } 776 777 /** 778 * Fill the entire canvas' bitmap (restricted to the current clip) with the 779 * specified color, using srcover porterduff mode. 780 * 781 * @param color the color to draw onto the canvas 782 */ 783 public void drawColor(int color) { 784 native_drawColor(mNativeCanvas, color); 785 } 786 787 /** 788 * Fill the entire canvas' bitmap (restricted to the current clip) with the 789 * specified color and porter-duff xfermode. 790 * 791 * @param color the color to draw with 792 * @param mode the porter-duff mode to apply to the color 793 */ 794 public void drawColor(int color, PorterDuff.Mode mode) { 795 native_drawColor(mNativeCanvas, color, mode.nativeInt); 796 } 797 798 /** 799 * Fill the entire canvas' bitmap (restricted to the current clip) with 800 * the specified paint. This is equivalent (but faster) to drawing an 801 * infinitely large rectangle with the specified paint. 802 * 803 * @param paint The paint used to draw onto the canvas 804 */ 805 public void drawPaint(Paint paint) { 806 native_drawPaint(mNativeCanvas, paint.mNativePaint); 807 } 808 809 /** 810 * Draw a series of points. Each point is centered at the coordinate 811 * specified by pts[], and its diameter is specified by the paint's stroke 812 * width (as transformed by the canvas' CTM), with special treatment for 813 * a stroke width of 0, which always draws exactly 1 pixel (or at most 4 814 * if antialiasing is enabled). The shape of the point is controlled by 815 * the paint's Cap type. The shape is a square, unless the cap type is 816 * Round, in which case the shape is a circle. 817 * 818 * @param pts Array of points to draw [x0 y0 x1 y1 x2 y2 ...] 819 * @param offset Number of values to skip before starting to draw. 820 * @param count The number of values to process, after skipping offset 821 * of them. Since one point uses two values, the number of 822 * "points" that are drawn is really (count >> 1). 823 * @param paint The paint used to draw the points 824 */ 825 public native void drawPoints(float[] pts, int offset, int count, 826 Paint paint); 827 828 /** 829 * Helper for drawPoints() that assumes you want to draw the entire array 830 */ 831 public void drawPoints(float[] pts, Paint paint) { 832 drawPoints(pts, 0, pts.length, paint); 833 } 834 835 /** 836 * Helper for drawPoints() for drawing a single point. 837 */ 838 public native void drawPoint(float x, float y, Paint paint); 839 840 /** 841 * Draw a line segment with the specified start and stop x,y coordinates, 842 * using the specified paint. NOTE: since a line is always "framed", the 843 * Style is ignored in the paint. 844 * 845 * @param startX The x-coordinate of the start point of the line 846 * @param startY The y-coordinate of the start point of the line 847 * @param paint The paint used to draw the line 848 */ 849 public void drawLine(float startX, float startY, float stopX, float stopY, 850 Paint paint) { 851 native_drawLine(mNativeCanvas, startX, startY, stopX, stopY, 852 paint.mNativePaint); 853 } 854 855 /** 856 * Draw a series of lines. Each line is taken from 4 consecutive values 857 * in the pts array. Thus to draw 1 line, the array must contain at least 4 858 * values. This is logically the same as drawing the array as follows: 859 * drawLine(pts[0], pts[1], pts[2], pts[3]) followed by 860 * drawLine(pts[4], pts[5], pts[6], pts[7]) and so on. 861 * 862 * @param pts Array of points to draw [x0 y0 x1 y1 x2 y2 ...] 863 * @param offset Number of values in the array to skip before drawing. 864 * @param count The number of values in the array to process, after 865 * skipping "offset" of them. Since each line uses 4 values, 866 * the number of "lines" that are drawn is really 867 * (count >> 2). 868 * @param paint The paint used to draw the points 869 */ 870 public native void drawLines(float[] pts, int offset, int count, 871 Paint paint); 872 873 public void drawLines(float[] pts, Paint paint) { 874 drawLines(pts, 0, pts.length, paint); 875 } 876 877 /** 878 * Draw the specified Rect using the specified paint. The rectangle will 879 * be filled or framed based on the Style in the paint. 880 * 881 * @param rect The rect to be drawn 882 * @param paint The paint used to draw the rect 883 */ 884 public void drawRect(RectF rect, Paint paint) { 885 native_drawRect(mNativeCanvas, rect, paint.mNativePaint); 886 } 887 888 /** 889 * Draw the specified Rect using the specified Paint. The rectangle 890 * will be filled or framed based on the Style in the paint. 891 * 892 * @param r The rectangle to be drawn. 893 * @param paint The paint used to draw the rectangle 894 */ 895 public void drawRect(Rect r, Paint paint) { 896 drawRect(r.left, r.top, r.right, r.bottom, paint); 897 } 898 899 900 /** 901 * Draw the specified Rect using the specified paint. The rectangle will 902 * be filled or framed based on the Style in the paint. 903 * 904 * @param left The left side of the rectangle to be drawn 905 * @param top The top side of the rectangle to be drawn 906 * @param right The right side of the rectangle to be drawn 907 * @param bottom The bottom side of the rectangle to be drawn 908 * @param paint The paint used to draw the rect 909 */ 910 public void drawRect(float left, float top, float right, float bottom, 911 Paint paint) { 912 native_drawRect(mNativeCanvas, left, top, right, bottom, 913 paint.mNativePaint); 914 } 915 916 /** 917 * Draw the specified oval using the specified paint. The oval will be 918 * filled or framed based on the Style in the paint. 919 * 920 * @param oval The rectangle bounds of the oval to be drawn 921 */ 922 public void drawOval(RectF oval, Paint paint) { 923 if (oval == null) { 924 throw new NullPointerException(); 925 } 926 native_drawOval(mNativeCanvas, oval, paint.mNativePaint); 927 } 928 929 /** 930 * Draw the specified circle using the specified paint. If radius is <= 0, 931 * then nothing will be drawn. The circle will be filled or framed based 932 * on the Style in the paint. 933 * 934 * @param cx The x-coordinate of the center of the cirle to be drawn 935 * @param cy The y-coordinate of the center of the cirle to be drawn 936 * @param radius The radius of the cirle to be drawn 937 * @param paint The paint used to draw the circle 938 */ 939 public void drawCircle(float cx, float cy, float radius, Paint paint) { 940 native_drawCircle(mNativeCanvas, cx, cy, radius, 941 paint.mNativePaint); 942 } 943 944 /** 945 * Draw the specified arc, which will be scaled to fit inside the 946 * specified oval. If the sweep angle is >= 360, then the oval is drawn 947 * completely. Note that this differs slightly from SkPath::arcTo, which 948 * treats the sweep angle mod 360. 949 * 950 * @param oval The bounds of oval used to define the shape and size 951 * of the arc 952 * @param startAngle Starting angle (in degrees) where the arc begins 953 * @param sweepAngle Sweep angle (in degrees) measured clockwise 954 * @param useCenter If true, include the center of the oval in the arc, and 955 close it if it is being stroked. This will draw a wedge 956 * @param paint The paint used to draw the arc 957 */ 958 public void drawArc(RectF oval, float startAngle, float sweepAngle, 959 boolean useCenter, Paint paint) { 960 if (oval == null) { 961 throw new NullPointerException(); 962 } 963 native_drawArc(mNativeCanvas, oval, startAngle, sweepAngle, 964 useCenter, paint.mNativePaint); 965 } 966 967 /** 968 * Draw the specified round-rect using the specified paint. The roundrect 969 * will be filled or framed based on the Style in the paint. 970 * 971 * @param rect The rectangular bounds of the roundRect to be drawn 972 * @param rx The x-radius of the oval used to round the corners 973 * @param ry The y-radius of the oval used to round the corners 974 * @param paint The paint used to draw the roundRect 975 */ 976 public void drawRoundRect(RectF rect, float rx, float ry, Paint paint) { 977 if (rect == null) { 978 throw new NullPointerException(); 979 } 980 native_drawRoundRect(mNativeCanvas, rect, rx, ry, 981 paint.mNativePaint); 982 } 983 984 /** 985 * Draw the specified path using the specified paint. The path will be 986 * filled or framed based on the Style in the paint. 987 * 988 * @param path The path to be drawn 989 * @param paint The paint used to draw the path 990 */ 991 public void drawPath(Path path, Paint paint) { 992 native_drawPath(mNativeCanvas, path.ni(), paint.mNativePaint); 993 } 994 995 private static void throwIfRecycled(Bitmap bitmap) { 996 if (bitmap.isRecycled()) { 997 throw new RuntimeException( 998 "Canvas: trying to use a recycled bitmap " + bitmap); 999 } 1000 } 1001 1002 /** 1003 * Draw the specified bitmap, with its top/left corner at (x,y), using 1004 * the specified paint, transformed by the current matrix. 1005 * 1006 * <p>Note: if the paint contains a maskfilter that generates a mask which 1007 * extends beyond the bitmap's original width/height (e.g. BlurMaskFilter), 1008 * then the bitmap will be drawn as if it were in a Shader with CLAMP mode. 1009 * Thus the color outside of the original width/height will be the edge 1010 * color replicated. 1011 * 1012 * <p>If the bitmap and canvas have different densities, this function 1013 * will take care of automatically scaling the bitmap to draw at the 1014 * same density as the canvas. 1015 * 1016 * @param bitmap The bitmap to be drawn 1017 * @param left The position of the left side of the bitmap being drawn 1018 * @param top The position of the top side of the bitmap being drawn 1019 * @param paint The paint used to draw the bitmap (may be null) 1020 */ 1021 public void drawBitmap(Bitmap bitmap, float left, float top, Paint paint) { 1022 throwIfRecycled(bitmap); 1023 native_drawBitmap(mNativeCanvas, bitmap.ni(), left, top, 1024 paint != null ? paint.mNativePaint : 0, mDensity, mScreenDensity, 1025 bitmap.mDensity); 1026 } 1027 1028 /** 1029 * Draw the specified bitmap, scaling/translating automatically to fill 1030 * the destination rectangle. If the source rectangle is not null, it 1031 * specifies the subset of the bitmap to draw. 1032 * 1033 * <p>Note: if the paint contains a maskfilter that generates a mask which 1034 * extends beyond the bitmap's original width/height (e.g. BlurMaskFilter), 1035 * then the bitmap will be drawn as if it were in a Shader with CLAMP mode. 1036 * Thus the color outside of the original width/height will be the edge 1037 * color replicated. 1038 * 1039 * <p>This function <em>ignores the density associated with the bitmap</em>. 1040 * This is because the source and destination rectangle coordinate 1041 * spaces are in their respective densities, so must already have the 1042 * appropriate scaling factor applied. 1043 * 1044 * @param bitmap The bitmap to be drawn 1045 * @param src May be null. The subset of the bitmap to be drawn 1046 * @param dst The rectangle that the bitmap will be scaled/translated 1047 * to fit into 1048 * @param paint May be null. The paint used to draw the bitmap 1049 */ 1050 public void drawBitmap(Bitmap bitmap, Rect src, RectF dst, Paint paint) { 1051 if (dst == null) { 1052 throw new NullPointerException(); 1053 } 1054 throwIfRecycled(bitmap); 1055 native_drawBitmap(mNativeCanvas, bitmap.ni(), src, dst, 1056 paint != null ? paint.mNativePaint : 0, 1057 mScreenDensity, bitmap.mDensity); 1058 } 1059 1060 /** 1061 * Draw the specified bitmap, scaling/translating automatically to fill 1062 * the destination rectangle. If the source rectangle is not null, it 1063 * specifies the subset of the bitmap to draw. 1064 * 1065 * <p>Note: if the paint contains a maskfilter that generates a mask which 1066 * extends beyond the bitmap's original width/height (e.g. BlurMaskFilter), 1067 * then the bitmap will be drawn as if it were in a Shader with CLAMP mode. 1068 * Thus the color outside of the original width/height will be the edge 1069 * color replicated. 1070 * 1071 * <p>This function <em>ignores the density associated with the bitmap</em>. 1072 * This is because the source and destination rectangle coordinate 1073 * spaces are in their respective densities, so must already have the 1074 * appropriate scaling factor applied. 1075 * 1076 * @param bitmap The bitmap to be drawn 1077 * @param src May be null. The subset of the bitmap to be drawn 1078 * @param dst The rectangle that the bitmap will be scaled/translated 1079 * to fit into 1080 * @param paint May be null. The paint used to draw the bitmap 1081 */ 1082 public void drawBitmap(Bitmap bitmap, Rect src, Rect dst, Paint paint) { 1083 if (dst == null) { 1084 throw new NullPointerException(); 1085 } 1086 throwIfRecycled(bitmap); 1087 native_drawBitmap(mNativeCanvas, bitmap.ni(), src, dst, 1088 paint != null ? paint.mNativePaint : 0, 1089 mScreenDensity, bitmap.mDensity); 1090 } 1091 1092 /** 1093 * Treat the specified array of colors as a bitmap, and draw it. This gives 1094 * the same result as first creating a bitmap from the array, and then 1095 * drawing it, but this method avoids explicitly creating a bitmap object 1096 * which can be more efficient if the colors are changing often. 1097 * 1098 * @param colors Array of colors representing the pixels of the bitmap 1099 * @param offset Offset into the array of colors for the first pixel 1100 * @param stride The number of of colors in the array between rows (must be 1101 * >= width or <= -width). 1102 * @param x The X coordinate for where to draw the bitmap 1103 * @param y The Y coordinate for where to draw the bitmap 1104 * @param width The width of the bitmap 1105 * @param height The height of the bitmap 1106 * @param hasAlpha True if the alpha channel of the colors contains valid 1107 * values. If false, the alpha byte is ignored (assumed to 1108 * be 0xFF for every pixel). 1109 * @param paint May be null. The paint used to draw the bitmap 1110 */ 1111 public void drawBitmap(int[] colors, int offset, int stride, float x, 1112 float y, int width, int height, boolean hasAlpha, 1113 Paint paint) { 1114 // check for valid input 1115 if (width < 0) { 1116 throw new IllegalArgumentException("width must be >= 0"); 1117 } 1118 if (height < 0) { 1119 throw new IllegalArgumentException("height must be >= 0"); 1120 } 1121 if (Math.abs(stride) < width) { 1122 throw new IllegalArgumentException("abs(stride) must be >= width"); 1123 } 1124 int lastScanline = offset + (height - 1) * stride; 1125 int length = colors.length; 1126 if (offset < 0 || (offset + width > length) || lastScanline < 0 1127 || (lastScanline + width > length)) { 1128 throw new ArrayIndexOutOfBoundsException(); 1129 } 1130 // quick escape if there's nothing to draw 1131 if (width == 0 || height == 0) { 1132 return; 1133 } 1134 // punch down to native for the actual draw 1135 native_drawBitmap(mNativeCanvas, colors, offset, stride, x, y, width, height, hasAlpha, 1136 paint != null ? paint.mNativePaint : 0); 1137 } 1138 1139 /** Legacy version of drawBitmap(int[] colors, ...) that took ints for x,y 1140 */ 1141 public void drawBitmap(int[] colors, int offset, int stride, int x, int y, 1142 int width, int height, boolean hasAlpha, 1143 Paint paint) { 1144 // call through to the common float version 1145 drawBitmap(colors, offset, stride, (float)x, (float)y, width, height, 1146 hasAlpha, paint); 1147 } 1148 1149 /** 1150 * Draw the bitmap using the specified matrix. 1151 * 1152 * @param bitmap The bitmap to draw 1153 * @param matrix The matrix used to transform the bitmap when it is drawn 1154 * @param paint May be null. The paint used to draw the bitmap 1155 */ 1156 public void drawBitmap(Bitmap bitmap, Matrix matrix, Paint paint) { 1157 nativeDrawBitmapMatrix(mNativeCanvas, bitmap.ni(), matrix.ni(), 1158 paint != null ? paint.mNativePaint : 0); 1159 } 1160 1161 private static void checkRange(int length, int offset, int count) { 1162 if ((offset | count) < 0 || offset + count > length) { 1163 throw new ArrayIndexOutOfBoundsException(); 1164 } 1165 } 1166 1167 /** 1168 * Draw the bitmap through the mesh, where mesh vertices are evenly 1169 * distributed across the bitmap. There are meshWidth+1 vertices across, and 1170 * meshHeight+1 vertices down. The verts array is accessed in row-major 1171 * order, so that the first meshWidth+1 vertices are distributed across the 1172 * top of the bitmap from left to right. A more general version of this 1173 * methid is drawVertices(). 1174 * 1175 * @param bitmap The bitmap to draw using the mesh 1176 * @param meshWidth The number of columns in the mesh. Nothing is drawn if 1177 * this is 0 1178 * @param meshHeight The number of rows in the mesh. Nothing is drawn if 1179 * this is 0 1180 * @param verts Array of x,y pairs, specifying where the mesh should be 1181 * drawn. There must be at least 1182 * (meshWidth+1) * (meshHeight+1) * 2 + meshOffset values 1183 * in the array 1184 * @param vertOffset Number of verts elements to skip before drawing 1185 * @param colors May be null. Specifies a color at each vertex, which is 1186 * interpolated across the cell, and whose values are 1187 * multiplied by the corresponding bitmap colors. If not null, 1188 * there must be at least (meshWidth+1) * (meshHeight+1) + 1189 * colorOffset values in the array. 1190 * @param colorOffset Number of color elements to skip before drawing 1191 * @param paint May be null. The paint used to draw the bitmap 1192 */ 1193 public void drawBitmapMesh(Bitmap bitmap, int meshWidth, int meshHeight, 1194 float[] verts, int vertOffset, 1195 int[] colors, int colorOffset, Paint paint) { 1196 if ((meshWidth | meshHeight | vertOffset | colorOffset) < 0) { 1197 throw new ArrayIndexOutOfBoundsException(); 1198 } 1199 if (meshWidth == 0 || meshHeight == 0) { 1200 return; 1201 } 1202 int count = (meshWidth + 1) * (meshHeight + 1); 1203 // we mul by 2 since we need two floats per vertex 1204 checkRange(verts.length, vertOffset, count * 2); 1205 if (colors != null) { 1206 // no mul by 2, since we need only 1 color per vertex 1207 checkRange(colors.length, colorOffset, count); 1208 } 1209 nativeDrawBitmapMesh(mNativeCanvas, bitmap.ni(), meshWidth, meshHeight, 1210 verts, vertOffset, colors, colorOffset, 1211 paint != null ? paint.mNativePaint : 0); 1212 } 1213 1214 public enum VertexMode { 1215 TRIANGLES(0), 1216 TRIANGLE_STRIP(1), 1217 TRIANGLE_FAN(2); 1218 1219 VertexMode(int nativeInt) { 1220 this.nativeInt = nativeInt; 1221 } 1222 final int nativeInt; 1223 } 1224 1225 /** 1226 * Draw the array of vertices, interpreted as triangles (based on mode). The 1227 * verts array is required, and specifies the x,y pairs for each vertex. If 1228 * texs is non-null, then it is used to specify the coordinate in shader 1229 * coordinates to use at each vertex (the paint must have a shader in this 1230 * case). If there is no texs array, but there is a color array, then each 1231 * color is interpolated across its corresponding triangle in a gradient. If 1232 * both texs and colors arrays are present, then they behave as before, but 1233 * the resulting color at each pixels is the result of multiplying the 1234 * colors from the shader and the color-gradient together. The indices array 1235 * is optional, but if it is present, then it is used to specify the index 1236 * of each triangle, rather than just walking through the arrays in order. 1237 * 1238 * @param mode How to interpret the array of vertices 1239 * @param vertexCount The number of values in the vertices array (and 1240 * corresponding texs and colors arrays if non-null). Each logical 1241 * vertex is two values (x, y), vertexCount must be a multiple of 2. 1242 * @param verts Array of vertices for the mesh 1243 * @param vertOffset Number of values in the verts to skip before drawing. 1244 * @param texs May be null. If not null, specifies the coordinates to sample 1245 * into the current shader (e.g. bitmap tile or gradient) 1246 * @param texOffset Number of values in texs to skip before drawing. 1247 * @param colors May be null. If not null, specifies a color for each 1248 * vertex, to be interpolated across the triangle. 1249 * @param colorOffset Number of values in colors to skip before drawing. 1250 * @param indices If not null, array of indices to reference into the 1251 * vertex (texs, colors) array. 1252 * @param indexCount number of entries in the indices array (if not null). 1253 * @param paint Specifies the shader to use if the texs array is non-null. 1254 */ 1255 public void drawVertices(VertexMode mode, int vertexCount, 1256 float[] verts, int vertOffset, 1257 float[] texs, int texOffset, 1258 int[] colors, int colorOffset, 1259 short[] indices, int indexOffset, 1260 int indexCount, Paint paint) { 1261 checkRange(verts.length, vertOffset, vertexCount); 1262 if (texs != null) { 1263 checkRange(texs.length, texOffset, vertexCount); 1264 } 1265 if (colors != null) { 1266 checkRange(colors.length, colorOffset, vertexCount / 2); 1267 } 1268 if (indices != null) { 1269 checkRange(indices.length, indexOffset, indexCount); 1270 } 1271 nativeDrawVertices(mNativeCanvas, mode.nativeInt, vertexCount, verts, 1272 vertOffset, texs, texOffset, colors, colorOffset, 1273 indices, indexOffset, indexCount, paint.mNativePaint); 1274 } 1275 1276 /** 1277 * Draw the text, with origin at (x,y), using the specified paint. The 1278 * origin is interpreted based on the Align setting in the paint. 1279 * 1280 * @param text The text to be drawn 1281 * @param x The x-coordinate of the origin of the text being drawn 1282 * @param y The y-coordinate of the origin of the text being drawn 1283 * @param paint The paint used for the text (e.g. color, size, style) 1284 */ 1285 public void drawText(char[] text, int index, int count, float x, float y, 1286 Paint paint) { 1287 if ((index | count | (index + count) | 1288 (text.length - index - count)) < 0) { 1289 throw new IndexOutOfBoundsException(); 1290 } 1291 native_drawText(mNativeCanvas, text, index, count, x, y, paint.mBidiFlags, 1292 paint.mNativePaint); 1293 } 1294 1295 /** 1296 * Draw the text, with origin at (x,y), using the specified paint. The 1297 * origin is interpreted based on the Align setting in the paint. 1298 * 1299 * @param text The text to be drawn 1300 * @param x The x-coordinate of the origin of the text being drawn 1301 * @param y The y-coordinate of the origin of the text being drawn 1302 * @param paint The paint used for the text (e.g. color, size, style) 1303 */ 1304 public void drawText(String text, float x, float y, Paint paint) { 1305 native_drawText(mNativeCanvas, text, 0, text.length(), x, y, paint.mBidiFlags, 1306 paint.mNativePaint); 1307 } 1308 1309 /** 1310 * Draw the text, with origin at (x,y), using the specified paint. 1311 * The origin is interpreted based on the Align setting in the paint. 1312 * 1313 * @param text The text to be drawn 1314 * @param start The index of the first character in text to draw 1315 * @param end (end - 1) is the index of the last character in text to draw 1316 * @param x The x-coordinate of the origin of the text being drawn 1317 * @param y The y-coordinate of the origin of the text being drawn 1318 * @param paint The paint used for the text (e.g. color, size, style) 1319 */ 1320 public void drawText(String text, int start, int end, float x, float y, 1321 Paint paint) { 1322 if ((start | end | (end - start) | (text.length() - end)) < 0) { 1323 throw new IndexOutOfBoundsException(); 1324 } 1325 native_drawText(mNativeCanvas, text, start, end, x, y, paint.mBidiFlags, 1326 paint.mNativePaint); 1327 } 1328 1329 /** 1330 * Draw the specified range of text, specified by start/end, with its 1331 * origin at (x,y), in the specified Paint. The origin is interpreted 1332 * based on the Align setting in the Paint. 1333 * 1334 * @param text The text to be drawn 1335 * @param start The index of the first character in text to draw 1336 * @param end (end - 1) is the index of the last character in text 1337 * to draw 1338 * @param x The x-coordinate of origin for where to draw the text 1339 * @param y The y-coordinate of origin for where to draw the text 1340 * @param paint The paint used for the text (e.g. color, size, style) 1341 */ 1342 public void drawText(CharSequence text, int start, int end, float x, 1343 float y, Paint paint) { 1344 if (text instanceof String || text instanceof SpannedString || 1345 text instanceof SpannableString) { 1346 native_drawText(mNativeCanvas, text.toString(), start, end, x, y, 1347 paint.mBidiFlags, paint.mNativePaint); 1348 } else if (text instanceof GraphicsOperations) { 1349 ((GraphicsOperations) text).drawText(this, start, end, x, y, 1350 paint); 1351 } else { 1352 char[] buf = TemporaryBuffer.obtain(end - start); 1353 TextUtils.getChars(text, start, end, buf, 0); 1354 native_drawText(mNativeCanvas, buf, 0, end - start, x, y, 1355 paint.mBidiFlags, paint.mNativePaint); 1356 TemporaryBuffer.recycle(buf); 1357 } 1358 } 1359 1360 /** 1361 * Render a run of all LTR or all RTL text, with shaping. This does not run 1362 * bidi on the provided text, but renders it as a uniform right-to-left or 1363 * left-to-right run, as indicated by dir. Alignment of the text is as 1364 * determined by the Paint's TextAlign value. 1365 * 1366 * @param text the text to render 1367 * @param index the start of the text to render 1368 * @param count the count of chars to render 1369 * @param contextIndex the start of the context for shaping. Must be 1370 * no greater than index. 1371 * @param contextCount the number of characters in the context for shaping. 1372 * ContexIndex + contextCount must be no less than index 1373 * + count. 1374 * @param x the x position at which to draw the text 1375 * @param y the y position at which to draw the text 1376 * @param dir the run direction, either {@link #DIRECTION_LTR} or 1377 * {@link #DIRECTION_RTL}. 1378 * @param paint the paint 1379 * @hide 1380 */ 1381 public void drawTextRun(char[] text, int index, int count, 1382 int contextIndex, int contextCount, float x, float y, int dir, 1383 Paint paint) { 1384 1385 if (text == null) { 1386 throw new NullPointerException("text is null"); 1387 } 1388 if (paint == null) { 1389 throw new NullPointerException("paint is null"); 1390 } 1391 if ((index | count | text.length - index - count) < 0) { 1392 throw new IndexOutOfBoundsException(); 1393 } 1394 if (dir != DIRECTION_LTR && dir != DIRECTION_RTL) { 1395 throw new IllegalArgumentException("unknown dir: " + dir); 1396 } 1397 1398 native_drawTextRun(mNativeCanvas, text, index, count, 1399 contextIndex, contextCount, x, y, dir, paint.mNativePaint); 1400 } 1401 1402 /** 1403 * Render a run of all LTR or all RTL text, with shaping. This does not run 1404 * bidi on the provided text, but renders it as a uniform right-to-left or 1405 * left-to-right run, as indicated by dir. Alignment of the text is as 1406 * determined by the Paint's TextAlign value. 1407 * 1408 * @param text the text to render 1409 * @param start the start of the text to render. Data before this position 1410 * can be used for shaping context. 1411 * @param end the end of the text to render. Data at or after this 1412 * position can be used for shaping context. 1413 * @param x the x position at which to draw the text 1414 * @param y the y position at which to draw the text 1415 * @param dir the run direction, either 0 for LTR or 1 for RTL. 1416 * @param paint the paint 1417 * @hide 1418 */ 1419 public void drawTextRun(CharSequence text, int start, int end, 1420 int contextStart, int contextEnd, float x, float y, int dir, 1421 Paint paint) { 1422 1423 if (text == null) { 1424 throw new NullPointerException("text is null"); 1425 } 1426 if (paint == null) { 1427 throw new NullPointerException("paint is null"); 1428 } 1429 if ((start | end | end - start | text.length() - end) < 0) { 1430 throw new IndexOutOfBoundsException(); 1431 } 1432 1433 int flags = dir == 0 ? 0 : 1; 1434 1435 if (text instanceof String || text instanceof SpannedString || 1436 text instanceof SpannableString) { 1437 native_drawTextRun(mNativeCanvas, text.toString(), start, end, 1438 contextStart, contextEnd, x, y, flags, paint.mNativePaint); 1439 } else if (text instanceof GraphicsOperations) { 1440 ((GraphicsOperations) text).drawTextRun(this, start, end, 1441 contextStart, contextEnd, x, y, flags, paint); 1442 } else { 1443 int contextLen = contextEnd - contextStart; 1444 int len = end - start; 1445 char[] buf = TemporaryBuffer.obtain(contextLen); 1446 TextUtils.getChars(text, contextStart, contextEnd, buf, 0); 1447 native_drawTextRun(mNativeCanvas, buf, start - contextStart, len, 1448 0, contextLen, x, y, flags, paint.mNativePaint); 1449 TemporaryBuffer.recycle(buf); 1450 } 1451 } 1452 1453 /** 1454 * Draw the text in the array, with each character's origin specified by 1455 * the pos array. 1456 * 1457 * @param text The text to be drawn 1458 * @param index The index of the first character to draw 1459 * @param count The number of characters to draw, starting from index. 1460 * @param pos Array of [x,y] positions, used to position each 1461 * character 1462 * @param paint The paint used for the text (e.g. color, size, style) 1463 */ 1464 public void drawPosText(char[] text, int index, int count, float[] pos, 1465 Paint paint) { 1466 if (index < 0 || index + count > text.length || count*2 > pos.length) { 1467 throw new IndexOutOfBoundsException(); 1468 } 1469 native_drawPosText(mNativeCanvas, text, index, count, pos, 1470 paint.mNativePaint); 1471 } 1472 1473 /** 1474 * Draw the text in the array, with each character's origin specified by 1475 * the pos array. 1476 * 1477 * @param text The text to be drawn 1478 * @param pos Array of [x,y] positions, used to position each character 1479 * @param paint The paint used for the text (e.g. color, size, style) 1480 */ 1481 public void drawPosText(String text, float[] pos, Paint paint) { 1482 if (text.length()*2 > pos.length) { 1483 throw new ArrayIndexOutOfBoundsException(); 1484 } 1485 native_drawPosText(mNativeCanvas, text, pos, paint.mNativePaint); 1486 } 1487 1488 /** 1489 * Draw the text, with origin at (x,y), using the specified paint, along 1490 * the specified path. The paint's Align setting determins where along the 1491 * path to start the text. 1492 * 1493 * @param text The text to be drawn 1494 * @param path The path the text should follow for its baseline 1495 * @param hOffset The distance along the path to add to the text's 1496 * starting position 1497 * @param vOffset The distance above(-) or below(+) the path to position 1498 * the text 1499 * @param paint The paint used for the text (e.g. color, size, style) 1500 */ 1501 public void drawTextOnPath(char[] text, int index, int count, Path path, 1502 float hOffset, float vOffset, Paint paint) { 1503 if (index < 0 || index + count > text.length) { 1504 throw new ArrayIndexOutOfBoundsException(); 1505 } 1506 native_drawTextOnPath(mNativeCanvas, text, index, count, 1507 path.ni(), hOffset, vOffset, 1508 paint.mNativePaint); 1509 } 1510 1511 /** 1512 * Draw the text, with origin at (x,y), using the specified paint, along 1513 * the specified path. The paint's Align setting determins where along the 1514 * path to start the text. 1515 * 1516 * @param text The text to be drawn 1517 * @param path The path the text should follow for its baseline 1518 * @param hOffset The distance along the path to add to the text's 1519 * starting position 1520 * @param vOffset The distance above(-) or below(+) the path to position 1521 * the text 1522 * @param paint The paint used for the text (e.g. color, size, style) 1523 */ 1524 public void drawTextOnPath(String text, Path path, float hOffset, 1525 float vOffset, Paint paint) { 1526 if (text.length() > 0) { 1527 native_drawTextOnPath(mNativeCanvas, text, path.ni(), 1528 hOffset, vOffset, paint.mNativePaint); 1529 } 1530 } 1531 1532 /** 1533 * Save the canvas state, draw the picture, and restore the canvas state. 1534 * This differs from picture.draw(canvas), which does not perform any 1535 * save/restore. 1536 * 1537 * @param picture The picture to be drawn 1538 */ 1539 public void drawPicture(Picture picture) { 1540 picture.endRecording(); 1541 native_drawPicture(mNativeCanvas, picture.ni()); 1542 } 1543 1544 /** 1545 * Draw the picture, stretched to fit into the dst rectangle. 1546 */ 1547 public void drawPicture(Picture picture, RectF dst) { 1548 save(); 1549 translate(dst.left, dst.top); 1550 if (picture.getWidth() > 0 && picture.getHeight() > 0) { 1551 scale(dst.width() / picture.getWidth(), 1552 dst.height() / picture.getHeight()); 1553 } 1554 drawPicture(picture); 1555 restore(); 1556 } 1557 1558 /** 1559 * Draw the picture, stretched to fit into the dst rectangle. 1560 */ 1561 public void drawPicture(Picture picture, Rect dst) { 1562 save(); 1563 translate(dst.left, dst.top); 1564 if (picture.getWidth() > 0 && picture.getHeight() > 0) { 1565 scale((float)dst.width() / picture.getWidth(), 1566 (float)dst.height() / picture.getHeight()); 1567 } 1568 drawPicture(picture); 1569 restore(); 1570 } 1571 1572 protected void finalize() throws Throwable { 1573 super.finalize(); 1574 // If the constructor threw an exception before setting mNativeCanvas, the native finalizer 1575 // must not be invoked. 1576 if (mNativeCanvas != 0) { 1577 finalizer(mNativeCanvas); 1578 } 1579 } 1580 1581 /** 1582 * Free up as much memory as possible from private caches (e.g. fonts, 1583 * images) 1584 * 1585 * @hide - for now 1586 */ 1587 public static native void freeCaches(); 1588 1589 private static native int initRaster(int nativeBitmapOrZero); 1590 private static native int initGL(); 1591 private static native void native_setBitmap(int nativeCanvas, int bitmap); 1592 private static native void nativeSetViewport(int nCanvas, int w, int h); 1593 private static native int native_saveLayer(int nativeCanvas, RectF bounds, 1594 int paint, int layerFlags); 1595 private static native int native_saveLayer(int nativeCanvas, float l, 1596 float t, float r, float b, 1597 int paint, int layerFlags); 1598 private static native int native_saveLayerAlpha(int nativeCanvas, 1599 RectF bounds, int alpha, 1600 int layerFlags); 1601 private static native int native_saveLayerAlpha(int nativeCanvas, float l, 1602 float t, float r, float b, 1603 int alpha, int layerFlags); 1604 1605 private static native void native_concat(int nCanvas, int nMatrix); 1606 private static native void native_setMatrix(int nCanvas, int nMatrix); 1607 private static native boolean native_clipRect(int nCanvas, 1608 float left, float top, 1609 float right, float bottom, 1610 int regionOp); 1611 private static native boolean native_clipPath(int nativeCanvas, 1612 int nativePath, 1613 int regionOp); 1614 private static native boolean native_clipRegion(int nativeCanvas, 1615 int nativeRegion, 1616 int regionOp); 1617 private static native void nativeSetDrawFilter(int nativeCanvas, 1618 int nativeFilter); 1619 private static native boolean native_getClipBounds(int nativeCanvas, 1620 Rect bounds); 1621 private static native void native_getCTM(int canvas, int matrix); 1622 private static native boolean native_quickReject(int nativeCanvas, 1623 RectF rect, 1624 int native_edgeType); 1625 private static native boolean native_quickReject(int nativeCanvas, 1626 int path, 1627 int native_edgeType); 1628 private static native boolean native_quickReject(int nativeCanvas, 1629 float left, float top, 1630 float right, float bottom, 1631 int native_edgeType); 1632 private static native void native_drawRGB(int nativeCanvas, int r, int g, 1633 int b); 1634 private static native void native_drawARGB(int nativeCanvas, int a, int r, 1635 int g, int b); 1636 private static native void native_drawColor(int nativeCanvas, int color); 1637 private static native void native_drawColor(int nativeCanvas, int color, 1638 int mode); 1639 private static native void native_drawPaint(int nativeCanvas, int paint); 1640 private static native void native_drawLine(int nativeCanvas, float startX, 1641 float startY, float stopX, 1642 float stopY, int paint); 1643 private static native void native_drawRect(int nativeCanvas, RectF rect, 1644 int paint); 1645 private static native void native_drawRect(int nativeCanvas, float left, 1646 float top, float right, 1647 float bottom, int paint); 1648 private static native void native_drawOval(int nativeCanvas, RectF oval, 1649 int paint); 1650 private static native void native_drawCircle(int nativeCanvas, float cx, 1651 float cy, float radius, 1652 int paint); 1653 private static native void native_drawArc(int nativeCanvas, RectF oval, 1654 float startAngle, float sweep, 1655 boolean useCenter, int paint); 1656 private static native void native_drawRoundRect(int nativeCanvas, 1657 RectF rect, float rx, 1658 float ry, int paint); 1659 private static native void native_drawPath(int nativeCanvas, int path, 1660 int paint); 1661 private native void native_drawBitmap(int nativeCanvas, int bitmap, 1662 float left, float top, 1663 int nativePaintOrZero, 1664 int canvasDensity, 1665 int screenDensity, 1666 int bitmapDensity); 1667 private native void native_drawBitmap(int nativeCanvas, int bitmap, 1668 Rect src, RectF dst, 1669 int nativePaintOrZero, 1670 int screenDensity, 1671 int bitmapDensity); 1672 private static native void native_drawBitmap(int nativeCanvas, int bitmap, 1673 Rect src, Rect dst, 1674 int nativePaintOrZero, 1675 int screenDensity, 1676 int bitmapDensity); 1677 private static native void native_drawBitmap(int nativeCanvas, int[] colors, 1678 int offset, int stride, float x, 1679 float y, int width, int height, 1680 boolean hasAlpha, 1681 int nativePaintOrZero); 1682 private static native void nativeDrawBitmapMatrix(int nCanvas, int nBitmap, 1683 int nMatrix, int nPaint); 1684 private static native void nativeDrawBitmapMesh(int nCanvas, int nBitmap, 1685 int meshWidth, int meshHeight, 1686 float[] verts, int vertOffset, 1687 int[] colors, int colorOffset, int nPaint); 1688 private static native void nativeDrawVertices(int nCanvas, int mode, int n, 1689 float[] verts, int vertOffset, float[] texs, int texOffset, 1690 int[] colors, int colorOffset, short[] indices, 1691 int indexOffset, int indexCount, int nPaint); 1692 1693 private static native void native_drawText(int nativeCanvas, char[] text, 1694 int index, int count, float x, 1695 float y, int flags, int paint); 1696 private static native void native_drawText(int nativeCanvas, String text, 1697 int start, int end, float x, 1698 float y, int flags, int paint); 1699 1700 private static native void native_drawTextRun(int nativeCanvas, String text, 1701 int start, int end, int contextStart, int contextEnd, 1702 float x, float y, int flags, int paint); 1703 1704 private static native void native_drawTextRun(int nativeCanvas, char[] text, 1705 int start, int count, int contextStart, int contextCount, 1706 float x, float y, int flags, int paint); 1707 1708 private static native void native_drawPosText(int nativeCanvas, 1709 char[] text, int index, 1710 int count, float[] pos, 1711 int paint); 1712 private static native void native_drawPosText(int nativeCanvas, 1713 String text, float[] pos, 1714 int paint); 1715 private static native void native_drawTextOnPath(int nativeCanvas, 1716 char[] text, int index, 1717 int count, int path, 1718 float hOffset, 1719 float vOffset, int paint); 1720 private static native void native_drawTextOnPath(int nativeCanvas, 1721 String text, int path, 1722 float hOffset, 1723 float vOffset, int paint); 1724 private static native void native_drawPicture(int nativeCanvas, 1725 int nativePicture); 1726 private static native void finalizer(int nativeCanvas); 1727} 1728