Canvas.java revision 0c702b88c5d0d4380930b920f5be6e66dd95a0d8
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 // Package-scoped for quick access. 51 /*package*/ int mDensity = Bitmap.DENSITY_NONE; 52 53 // Used to determine when compatibility scaling is in effect. 54 private int mScreenDensity = Bitmap.DENSITY_NONE; 55 56 // Used by native code 57 @SuppressWarnings({"UnusedDeclaration"}) 58 private int mSurfaceFormat; 59 60 /** 61 * Flag for drawTextRun indicating left-to-right run direction. 62 * @hide 63 */ 64 public static final int DIRECTION_LTR = 0; 65 66 /** 67 * Flag for drawTextRun indicating right-to-left run direction. 68 * @hide 69 */ 70 public static final int DIRECTION_RTL = 1; 71 72 /** 73 * Construct an empty raster canvas. Use setBitmap() to specify a bitmap to 74 * draw into. The initial target density is {@link Bitmap#DENSITY_NONE}; 75 * this will typically be replaced when a target bitmap is set for the 76 * canvas. 77 */ 78 public Canvas() { 79 // 0 means no native bitmap 80 mNativeCanvas = initRaster(0); 81 } 82 83 /** 84 * Construct a canvas with the specified bitmap to draw into. The bitmap 85 * must be mutable. 86 * 87 * <p>The initial target density of the canvas is the same as the given 88 * bitmap's density. 89 * 90 * @param bitmap Specifies a mutable bitmap for the canvas to draw into. 91 */ 92 public Canvas(Bitmap bitmap) { 93 if (!bitmap.isMutable()) { 94 throw new IllegalStateException( 95 "Immutable bitmap passed to Canvas constructor"); 96 } 97 throwIfRecycled(bitmap); 98 mNativeCanvas = initRaster(bitmap.ni()); 99 mBitmap = bitmap; 100 mDensity = bitmap.mDensity; 101 } 102 103 /*package*/ Canvas(int nativeCanvas) { 104 if (nativeCanvas == 0) { 105 throw new IllegalStateException(); 106 } 107 mNativeCanvas = nativeCanvas; 108 mDensity = Bitmap.getDefaultDensity(); 109 } 110 111 /** 112 * Construct a canvas with the specified gl context. All drawing through 113 * this canvas will be redirected to OpenGL. Note: some features may not 114 * be supported in this mode (e.g. some GL implementations may not support 115 * antialiasing or certain effects like ColorMatrix or certain Xfermodes). 116 * However, no exception will be thrown in those cases. 117 * 118 * <p>The initial target density of the canvas is the same as the initial 119 * density of bitmaps as per {@link Bitmap#getDensity() Bitmap.getDensity()}. 120 * 121 * @deprecated This constructor is not supported and should not be invoked. 122 */ 123 public Canvas(GL gl) { 124 mNativeCanvas = initGL(); 125 mGL = gl; 126 mDensity = Bitmap.getDefaultDensity(); 127 } 128 129 /** 130 * Indicates whether this Canvas uses hardware acceleration. 131 * 132 * Note that this method does not define what type of hardware acceleration 133 * may or may not be used. 134 * 135 * @return True if drawing operations are hardware accelerated, 136 * false otherwise. 137 */ 138 public boolean isHardwareAccelerated() { 139 return mGL != null; 140 } 141 142 /** 143 * Return the GL object associated with this canvas, or null if it is not 144 * backed by GL. 145 * 146 * @deprecated This method is not supported and should not be invoked. 147 */ 148 public GL getGL() { 149 return mGL; 150 } 151 152 /** 153 * Call this to free up OpenGL resources that may be cached or allocated 154 * on behalf of the Canvas. Any subsequent drawing with a GL-backed Canvas 155 * will have to recreate those resources. 156 * 157 * @deprecated This method is not supported and should not be invoked. 158 */ 159 public static void freeGlCaches() { 160 freeCaches(); 161 } 162 163 /** 164 * Specify a bitmap for the canvas to draw into. As a side-effect, also 165 * updates the canvas's target density to match that of the bitmap. 166 * 167 * @param bitmap Specifies a mutable bitmap for the canvas to draw into. 168 * 169 * @see #setDensity(int) 170 * @see #getDensity() 171 */ 172 public void setBitmap(Bitmap bitmap) { 173 if (!bitmap.isMutable()) { 174 throw new IllegalStateException(); 175 } 176 if (mGL != null) { 177 throw new RuntimeException("Can't set a bitmap device on a GL canvas"); 178 } 179 throwIfRecycled(bitmap); 180 181 native_setBitmap(mNativeCanvas, bitmap.ni()); 182 mBitmap = bitmap; 183 mDensity = bitmap.mDensity; 184 } 185 186 /** 187 * Set the viewport dimensions if this canvas is GL based. If it is not, 188 * this method is ignored and no exception is thrown. 189 * 190 * @param width The width of the viewport 191 * @param height The height of the viewport 192 * 193 * @deprecated This method is not supported and should not be invoked. 194 */ 195 public void setViewport(int width, int height) { 196 if (mGL != null) { 197 nativeSetViewport(mNativeCanvas, width, height); 198 } 199 } 200 201 /** 202 * Return true if the device that the current layer draws into is opaque 203 * (i.e. does not support per-pixel alpha). 204 * 205 * @return true if the device that the current layer draws into is opaque 206 */ 207 public native boolean isOpaque(); 208 209 /** 210 * Returns the width of the current drawing layer 211 * 212 * @return the width of the current drawing layer 213 */ 214 public native int getWidth(); 215 216 /** 217 * Returns the height of the current drawing layer 218 * 219 * @return the height of the current drawing layer 220 */ 221 public native int getHeight(); 222 223 /** 224 * <p>Returns the target density of the canvas. The default density is 225 * derived from the density of its backing bitmap, or 226 * {@link Bitmap#DENSITY_NONE} if there is not one.</p> 227 * 228 * @return Returns the current target density of the canvas, which is used 229 * to determine the scaling factor when drawing a bitmap into it. 230 * 231 * @see #setDensity(int) 232 * @see Bitmap#getDensity() 233 */ 234 public int getDensity() { 235 return mDensity; 236 } 237 238 /** 239 * <p>Specifies the density for this Canvas' backing bitmap. This modifies 240 * the target density of the canvas itself, as well as the density of its 241 * backing bitmap via {@link Bitmap#setDensity(int) Bitmap.setDensity(int)}. 242 * 243 * @param density The new target density of the canvas, which is used 244 * to determine the scaling factor when drawing a bitmap into it. Use 245 * {@link Bitmap#DENSITY_NONE} to disable bitmap scaling. 246 * 247 * @see #getDensity() 248 * @see Bitmap#setDensity(int) 249 */ 250 public void setDensity(int density) { 251 if (mBitmap != null) { 252 mBitmap.setDensity(density); 253 } 254 mDensity = density; 255 } 256 257 /** @hide */ 258 public void setScreenDensity(int density) { 259 mScreenDensity = density; 260 } 261 262 // the SAVE_FLAG constants must match their native equivalents 263 264 /** restore the current matrix when restore() is called */ 265 public static final int MATRIX_SAVE_FLAG = 0x01; 266 /** restore the current clip when restore() is called */ 267 public static final int CLIP_SAVE_FLAG = 0x02; 268 /** the layer needs to per-pixel alpha */ 269 public static final int HAS_ALPHA_LAYER_SAVE_FLAG = 0x04; 270 /** the layer needs to 8-bits per color component */ 271 public static final int FULL_COLOR_LAYER_SAVE_FLAG = 0x08; 272 /** clip against the layer's bounds */ 273 public static final int CLIP_TO_LAYER_SAVE_FLAG = 0x10; 274 /** restore everything when restore() is called */ 275 public static final int ALL_SAVE_FLAG = 0x1F; 276 277 /** 278 * Saves the current matrix and clip onto a private stack. Subsequent 279 * calls to translate,scale,rotate,skew,concat or clipRect,clipPath 280 * will all operate as usual, but when the balancing call to restore() 281 * is made, those calls will be forgotten, and the settings that existed 282 * before the save() will be reinstated. 283 * 284 * @return The value to pass to restoreToCount() to balance this save() 285 */ 286 public native int save(); 287 288 /** 289 * Based on saveFlags, can save the current matrix and clip onto a private 290 * stack. Subsequent calls to translate,scale,rotate,skew,concat or 291 * clipRect,clipPath will all operate as usual, but when the balancing 292 * call to restore() is made, those calls will be forgotten, and the 293 * settings that existed before the save() will be reinstated. 294 * 295 * @param saveFlags flag bits that specify which parts of the Canvas state 296 * to save/restore 297 * @return The value to pass to restoreToCount() to balance this save() 298 */ 299 public native int save(int saveFlags); 300 301 /** 302 * This behaves the same as save(), but in addition it allocates an 303 * offscreen bitmap. All drawing calls are directed there, and only when 304 * the balancing call to restore() is made is that offscreen transfered to 305 * the canvas (or the previous layer). Subsequent calls to translate, 306 * scale, rotate, skew, concat or clipRect, clipPath all operate on this 307 * copy. When the balancing call to restore() is made, this copy is 308 * deleted and the previous matrix/clip state is restored. 309 * 310 * @param bounds May be null. The maximum size the offscreen bitmap 311 * needs to be (in local coordinates) 312 * @param paint This is copied, and is applied to the offscreen when 313 * restore() is called. 314 * @param saveFlags see _SAVE_FLAG constants 315 * @return value to pass to restoreToCount() to balance this save() 316 */ 317 public int saveLayer(RectF bounds, Paint paint, int saveFlags) { 318 return native_saveLayer(mNativeCanvas, bounds, 319 paint != null ? paint.mNativePaint : 0, 320 saveFlags); 321 } 322 323 /** 324 * Helper version of saveLayer() that takes 4 values rather than a RectF. 325 */ 326 public int saveLayer(float left, float top, float right, float bottom, 327 Paint paint, int saveFlags) { 328 return native_saveLayer(mNativeCanvas, left, top, right, bottom, 329 paint != null ? paint.mNativePaint : 0, 330 saveFlags); 331 } 332 333 /** 334 * This behaves the same as save(), but in addition it allocates an 335 * offscreen bitmap. All drawing calls are directed there, and only when 336 * the balancing call to restore() is made is that offscreen transfered to 337 * the canvas (or the previous layer). Subsequent calls to translate, 338 * scale, rotate, skew, concat or clipRect, clipPath all operate on this 339 * copy. When the balancing call to restore() is made, this copy is 340 * deleted and the previous matrix/clip state is restored. 341 * 342 * @param bounds The maximum size the offscreen bitmap needs to be 343 * (in local coordinates) 344 * @param alpha The alpha to apply to the offscreen when when it is 345 drawn during restore() 346 * @param saveFlags see _SAVE_FLAG constants 347 * @return value to pass to restoreToCount() to balance this call 348 */ 349 public int saveLayerAlpha(RectF bounds, int alpha, int saveFlags) { 350 alpha = Math.min(255, Math.max(0, alpha)); 351 return native_saveLayerAlpha(mNativeCanvas, bounds, alpha, saveFlags); 352 } 353 354 /** 355 * Helper for saveLayerAlpha() that takes 4 values instead of a RectF. 356 */ 357 public int saveLayerAlpha(float left, float top, float right, float bottom, 358 int alpha, int saveFlags) { 359 return native_saveLayerAlpha(mNativeCanvas, left, top, right, bottom, 360 alpha, saveFlags); 361 } 362 363 /** 364 * This call balances a previous call to save(), and is used to remove all 365 * modifications to the matrix/clip state since the last save call. It is 366 * an error to call restore() more times than save() was called. 367 */ 368 public native void restore(); 369 370 /** 371 * Returns the number of matrix/clip states on the Canvas' private stack. 372 * This will equal # save() calls - # restore() calls. 373 */ 374 public native int getSaveCount(); 375 376 /** 377 * Efficient way to pop any calls to save() that happened after the save 378 * count reached saveCount. It is an error for saveCount to be less than 1. 379 * 380 * Example: 381 * int count = canvas.save(); 382 * ... // more calls potentially to save() 383 * canvas.restoreToCount(count); 384 * // now the canvas is back in the same state it was before the initial 385 * // call to save(). 386 * 387 * @param saveCount The save level to restore to. 388 */ 389 public native void restoreToCount(int saveCount); 390 391 /** 392 * Preconcat the current matrix with the specified translation 393 * 394 * @param dx The distance to translate in X 395 * @param dy The distance to translate in Y 396 */ 397 public native void translate(float dx, float dy); 398 399 /** 400 * Preconcat the current matrix with the specified scale. 401 * 402 * @param sx The amount to scale in X 403 * @param sy The amount to scale in Y 404 */ 405 public native void scale(float sx, float sy); 406 407 /** 408 * Preconcat the current matrix with the specified scale. 409 * 410 * @param sx The amount to scale in X 411 * @param sy The amount to scale in Y 412 * @param px The x-coord for the pivot point (unchanged by the rotation) 413 * @param py The y-coord for the pivot point (unchanged by the rotation) 414 */ 415 public final void scale(float sx, float sy, float px, float py) { 416 translate(px, py); 417 scale(sx, sy); 418 translate(-px, -py); 419 } 420 421 /** 422 * Preconcat the current matrix with the specified rotation. 423 * 424 * @param degrees The amount to rotate, in degrees 425 */ 426 public native void rotate(float degrees); 427 428 /** 429 * Preconcat the current matrix with the specified rotation. 430 * 431 * @param degrees The amount to rotate, in degrees 432 * @param px The x-coord for the pivot point (unchanged by the rotation) 433 * @param py The y-coord for the pivot point (unchanged by the rotation) 434 */ 435 public final void rotate(float degrees, float px, float py) { 436 translate(px, py); 437 rotate(degrees); 438 translate(-px, -py); 439 } 440 441 /** 442 * Preconcat the current matrix with the specified skew. 443 * 444 * @param sx The amount to skew in X 445 * @param sy The amount to skew in Y 446 */ 447 public native void skew(float sx, float sy); 448 449 /** 450 * Preconcat the current matrix with the specified matrix. 451 * 452 * @param matrix The matrix to preconcatenate with the current matrix 453 */ 454 public void concat(Matrix matrix) { 455 native_concat(mNativeCanvas, matrix.native_instance); 456 } 457 458 /** 459 * Completely replace the current matrix with the specified matrix. If the 460 * matrix parameter is null, then the current matrix is reset to identity. 461 * 462 * @param matrix The matrix to replace the current matrix with. If it is 463 * null, set the current matrix to identity. 464 */ 465 public void setMatrix(Matrix matrix) { 466 native_setMatrix(mNativeCanvas, 467 matrix == null ? 0 : matrix.native_instance); 468 } 469 470 /** 471 * Return, in ctm, the current transformation matrix. This does not alter 472 * the matrix in the canvas, but just returns a copy of it. 473 */ 474 public void getMatrix(Matrix ctm) { 475 native_getCTM(mNativeCanvas, ctm.native_instance); 476 } 477 478 /** 479 * Return a new matrix with a copy of the canvas' current transformation 480 * matrix. 481 */ 482 public final Matrix getMatrix() { 483 Matrix m = new Matrix(); 484 getMatrix(m); 485 return m; 486 } 487 488 /** 489 * Modify the current clip with the specified rectangle. 490 * 491 * @param rect The rect to intersect with the current clip 492 * @param op How the clip is modified 493 * @return true if the resulting clip is non-empty 494 */ 495 public boolean clipRect(RectF rect, Region.Op op) { 496 return native_clipRect(mNativeCanvas, 497 rect.left, rect.top, rect.right, rect.bottom, 498 op.nativeInt); 499 } 500 501 /** 502 * Modify the current clip with the specified rectangle, which is 503 * expressed in local coordinates. 504 * 505 * @param rect The rectangle to intersect with the current clip. 506 * @param op How the clip is modified 507 * @return true if the resulting clip is non-empty 508 */ 509 public boolean clipRect(Rect rect, Region.Op op) { 510 return native_clipRect(mNativeCanvas, 511 rect.left, rect.top, rect.right, rect.bottom, 512 op.nativeInt); 513 } 514 515 /** 516 * Intersect the current clip with the specified rectangle, which is 517 * expressed in local coordinates. 518 * 519 * @param rect The rectangle to intersect with the current clip. 520 * @return true if the resulting clip is non-empty 521 */ 522 public native boolean clipRect(RectF rect); 523 524 /** 525 * Intersect the current clip with the specified rectangle, which is 526 * expressed in local coordinates. 527 * 528 * @param rect The rectangle to intersect with the current clip. 529 * @return true if the resulting clip is non-empty 530 */ 531 public native boolean clipRect(Rect rect); 532 533 /** 534 * Modify the current clip with the specified rectangle, which is 535 * expressed in local coordinates. 536 * 537 * @param left The left side of the rectangle to intersect with the 538 * current clip 539 * @param top The top of the rectangle to intersect with the current 540 * clip 541 * @param right The right side of the rectangle to intersect with the 542 * current clip 543 * @param bottom The bottom of the rectangle to intersect with the current 544 * clip 545 * @param op How the clip is modified 546 * @return true if the resulting clip is non-empty 547 */ 548 public boolean clipRect(float left, float top, float right, float bottom, 549 Region.Op op) { 550 return native_clipRect(mNativeCanvas, left, top, right, bottom, 551 op.nativeInt); 552 } 553 554 /** 555 * Intersect the current clip with the specified rectangle, which is 556 * expressed in local coordinates. 557 * 558 * @param left The left side of the rectangle to intersect with the 559 * current clip 560 * @param top The top of the rectangle to intersect with the current clip 561 * @param right The right side of the rectangle to intersect with the 562 * current clip 563 * @param bottom The bottom of the rectangle to intersect with the current 564 * clip 565 * @return true if the resulting clip is non-empty 566 */ 567 public native boolean clipRect(float left, float top, 568 float right, float bottom); 569 570 /** 571 * Intersect the current clip with the specified rectangle, which is 572 * expressed in local coordinates. 573 * 574 * @param left The left side of the rectangle to intersect with the 575 * current clip 576 * @param top The top of the rectangle to intersect with the current clip 577 * @param right The right side of the rectangle to intersect with the 578 * current clip 579 * @param bottom The bottom of the rectangle to intersect with the current 580 * clip 581 * @return true if the resulting clip is non-empty 582 */ 583 public native boolean clipRect(int left, int top, 584 int right, int bottom); 585 586 /** 587 * Modify the current clip with the specified path. 588 * 589 * @param path The path to operate on the current clip 590 * @param op How the clip is modified 591 * @return true if the resulting is non-empty 592 */ 593 public boolean clipPath(Path path, Region.Op op) { 594 return native_clipPath(mNativeCanvas, path.ni(), op.nativeInt); 595 } 596 597 /** 598 * Intersect the current clip with the specified path. 599 * 600 * @param path The path to intersect with the current clip 601 * @return true if the resulting is non-empty 602 */ 603 public boolean clipPath(Path path) { 604 return clipPath(path, Region.Op.INTERSECT); 605 } 606 607 /** 608 * Modify the current clip with the specified region. Note that unlike 609 * clipRect() and clipPath() which transform their arguments by the 610 * current matrix, clipRegion() assumes its argument is already in the 611 * coordinate system of the current layer's bitmap, and so not 612 * transformation is performed. 613 * 614 * @param region The region to operate on the current clip, based on op 615 * @param op How the clip is modified 616 * @return true if the resulting is non-empty 617 */ 618 public boolean clipRegion(Region region, Region.Op op) { 619 return native_clipRegion(mNativeCanvas, region.ni(), op.nativeInt); 620 } 621 622 /** 623 * Intersect the current clip with the specified region. Note that unlike 624 * clipRect() and clipPath() which transform their arguments by the 625 * current matrix, clipRegion() assumes its argument is already in the 626 * coordinate system of the current layer's bitmap, and so not 627 * transformation is performed. 628 * 629 * @param region The region to operate on the current clip, based on op 630 * @return true if the resulting is non-empty 631 */ 632 public boolean clipRegion(Region region) { 633 return clipRegion(region, Region.Op.INTERSECT); 634 } 635 636 public DrawFilter getDrawFilter() { 637 return mDrawFilter; 638 } 639 640 public void setDrawFilter(DrawFilter filter) { 641 int nativeFilter = 0; 642 if (filter != null) { 643 nativeFilter = filter.mNativeInt; 644 } 645 mDrawFilter = filter; 646 nativeSetDrawFilter(mNativeCanvas, nativeFilter); 647 } 648 649 public enum EdgeType { 650 BW(0), //!< treat edges by just rounding to nearest pixel boundary 651 AA(1); //!< treat edges by rounding-out, since they may be antialiased 652 653 EdgeType(int nativeInt) { 654 this.nativeInt = nativeInt; 655 } 656 final int nativeInt; 657 } 658 659 /** 660 * Return true if the specified rectangle, after being transformed by the 661 * current matrix, would lie completely outside of the current clip. Call 662 * this to check if an area you intend to draw into is clipped out (and 663 * therefore you can skip making the draw calls). 664 * 665 * @param rect the rect to compare with the current clip 666 * @param type specifies how to treat the edges (BW or antialiased) 667 * @return true if the rect (transformed by the canvas' matrix) 668 * does not intersect with the canvas' clip 669 */ 670 public boolean quickReject(RectF rect, EdgeType type) { 671 return native_quickReject(mNativeCanvas, rect, type.nativeInt); 672 } 673 674 /** 675 * Return true if the specified path, after being transformed by the 676 * current matrix, would lie completely outside of the current clip. Call 677 * this to check if an area you intend to draw into is clipped out (and 678 * therefore you can skip making the draw calls). Note: for speed it may 679 * return false even if the path itself might not intersect the clip 680 * (i.e. the bounds of the path intersects, but the path does not). 681 * 682 * @param path The path to compare with the current clip 683 * @param type true if the path should be considered antialiased, 684 * since that means it may 685 * affect a larger area (more pixels) than 686 * non-antialiased. 687 * @return true if the path (transformed by the canvas' matrix) 688 * does not intersect with the canvas' clip 689 */ 690 public boolean quickReject(Path path, EdgeType type) { 691 return native_quickReject(mNativeCanvas, path.ni(), type.nativeInt); 692 } 693 694 /** 695 * Return true if the specified rectangle, after being transformed by the 696 * current matrix, would lie completely outside of the current clip. Call 697 * this to check if an area you intend to draw into is clipped out (and 698 * therefore you can skip making the draw calls). 699 * 700 * @param left The left side of the rectangle to compare with the 701 * current clip 702 * @param top The top of the rectangle to compare with the current 703 * clip 704 * @param right The right side of the rectangle to compare with the 705 * current clip 706 * @param bottom The bottom of the rectangle to compare with the 707 * current clip 708 * @param type true if the rect should be considered antialiased, 709 * since that means it may affect a larger area (more 710 * pixels) than non-antialiased. 711 * @return true if the rect (transformed by the canvas' matrix) 712 * does not intersect with the canvas' clip 713 */ 714 public boolean quickReject(float left, float top, float right, float bottom, 715 EdgeType type) { 716 return native_quickReject(mNativeCanvas, left, top, right, bottom, 717 type.nativeInt); 718 } 719 720 /** 721 * Retrieve the clip bounds, returning true if they are non-empty. 722 * 723 * @param bounds Return the clip bounds here. If it is null, ignore it but 724 * still return true if the current clip is non-empty. 725 * @return true if the current clip is non-empty. 726 */ 727 public boolean getClipBounds(Rect bounds) { 728 return native_getClipBounds(mNativeCanvas, bounds); 729 } 730 731 /** 732 * Retrieve the clip bounds. 733 * 734 * @return the clip bounds, or [0, 0, 0, 0] if the clip is empty. 735 */ 736 public final Rect getClipBounds() { 737 Rect r = new Rect(); 738 getClipBounds(r); 739 return r; 740 } 741 742 /** 743 * Fill the entire canvas' bitmap (restricted to the current clip) with the 744 * specified RGB color, using srcover porterduff mode. 745 * 746 * @param r red component (0..255) of the color to draw onto the canvas 747 * @param g green component (0..255) of the color to draw onto the canvas 748 * @param b blue component (0..255) of the color to draw onto the canvas 749 */ 750 public void drawRGB(int r, int g, int b) { 751 native_drawRGB(mNativeCanvas, r, g, b); 752 } 753 754 /** 755 * Fill the entire canvas' bitmap (restricted to the current clip) with the 756 * specified ARGB color, using srcover porterduff mode. 757 * 758 * @param a alpha component (0..255) of the color to draw onto the canvas 759 * @param r red component (0..255) of the color to draw onto the canvas 760 * @param g green component (0..255) of the color to draw onto the canvas 761 * @param b blue component (0..255) of the color to draw onto the canvas 762 */ 763 public void drawARGB(int a, int r, int g, int b) { 764 native_drawARGB(mNativeCanvas, a, r, g, b); 765 } 766 767 /** 768 * Fill the entire canvas' bitmap (restricted to the current clip) with the 769 * specified color, using srcover porterduff mode. 770 * 771 * @param color the color to draw onto the canvas 772 */ 773 public void drawColor(int color) { 774 native_drawColor(mNativeCanvas, color); 775 } 776 777 /** 778 * Fill the entire canvas' bitmap (restricted to the current clip) with the 779 * specified color and porter-duff xfermode. 780 * 781 * @param color the color to draw with 782 * @param mode the porter-duff mode to apply to the color 783 */ 784 public void drawColor(int color, PorterDuff.Mode mode) { 785 native_drawColor(mNativeCanvas, color, mode.nativeInt); 786 } 787 788 /** 789 * Fill the entire canvas' bitmap (restricted to the current clip) with 790 * the specified paint. This is equivalent (but faster) to drawing an 791 * infinitely large rectangle with the specified paint. 792 * 793 * @param paint The paint used to draw onto the canvas 794 */ 795 public void drawPaint(Paint paint) { 796 native_drawPaint(mNativeCanvas, paint.mNativePaint); 797 } 798 799 /** 800 * Draw a series of points. Each point is centered at the coordinate 801 * specified by pts[], and its diameter is specified by the paint's stroke 802 * width (as transformed by the canvas' CTM), with special treatment for 803 * a stroke width of 0, which always draws exactly 1 pixel (or at most 4 804 * if antialiasing is enabled). The shape of the point is controlled by 805 * the paint's Cap type. The shape is a square, unless the cap type is 806 * Round, in which case the shape is a circle. 807 * 808 * @param pts Array of points to draw [x0 y0 x1 y1 x2 y2 ...] 809 * @param offset Number of values to skip before starting to draw. 810 * @param count The number of values to process, after skipping offset 811 * of them. Since one point uses two values, the number of 812 * "points" that are drawn is really (count >> 1). 813 * @param paint The paint used to draw the points 814 */ 815 public native void drawPoints(float[] pts, int offset, int count, 816 Paint paint); 817 818 /** 819 * Helper for drawPoints() that assumes you want to draw the entire array 820 */ 821 public void drawPoints(float[] pts, Paint paint) { 822 drawPoints(pts, 0, pts.length, paint); 823 } 824 825 /** 826 * Helper for drawPoints() for drawing a single point. 827 */ 828 public native void drawPoint(float x, float y, Paint paint); 829 830 /** 831 * Draw a line segment with the specified start and stop x,y coordinates, 832 * using the specified paint. NOTE: since a line is always "framed", the 833 * Style is ignored in the paint. 834 * 835 * @param startX The x-coordinate of the start point of the line 836 * @param startY The y-coordinate of the start point of the line 837 * @param paint The paint used to draw the line 838 */ 839 public void drawLine(float startX, float startY, float stopX, float stopY, 840 Paint paint) { 841 native_drawLine(mNativeCanvas, startX, startY, stopX, stopY, 842 paint.mNativePaint); 843 } 844 845 /** 846 * Draw a series of lines. Each line is taken from 4 consecutive values 847 * in the pts array. Thus to draw 1 line, the array must contain at least 4 848 * values. This is logically the same as drawing the array as follows: 849 * drawLine(pts[0], pts[1], pts[2], pts[3]) followed by 850 * drawLine(pts[4], pts[5], pts[6], pts[7]) and so on. 851 * 852 * @param pts Array of points to draw [x0 y0 x1 y1 x2 y2 ...] 853 * @param offset Number of values in the array to skip before drawing. 854 * @param count The number of values in the array to process, after 855 * skipping "offset" of them. Since each line uses 4 values, 856 * the number of "lines" that are drawn is really 857 * (count >> 2). 858 * @param paint The paint used to draw the points 859 */ 860 public native void drawLines(float[] pts, int offset, int count, 861 Paint paint); 862 863 public void drawLines(float[] pts, Paint paint) { 864 drawLines(pts, 0, pts.length, paint); 865 } 866 867 /** 868 * Draw the specified Rect using the specified paint. The rectangle will 869 * be filled or framed based on the Style in the paint. 870 * 871 * @param rect The rect to be drawn 872 * @param paint The paint used to draw the rect 873 */ 874 public void drawRect(RectF rect, Paint paint) { 875 native_drawRect(mNativeCanvas, rect, paint.mNativePaint); 876 } 877 878 /** 879 * Draw the specified Rect using the specified Paint. The rectangle 880 * will be filled or framed based on the Style in the paint. 881 * 882 * @param r The rectangle to be drawn. 883 * @param paint The paint used to draw the rectangle 884 */ 885 public void drawRect(Rect r, Paint paint) { 886 drawRect(r.left, r.top, r.right, r.bottom, paint); 887 } 888 889 890 /** 891 * Draw the specified Rect using the specified paint. The rectangle will 892 * be filled or framed based on the Style in the paint. 893 * 894 * @param left The left side of the rectangle to be drawn 895 * @param top The top side of the rectangle to be drawn 896 * @param right The right side of the rectangle to be drawn 897 * @param bottom The bottom side of the rectangle to be drawn 898 * @param paint The paint used to draw the rect 899 */ 900 public void drawRect(float left, float top, float right, float bottom, 901 Paint paint) { 902 native_drawRect(mNativeCanvas, left, top, right, bottom, 903 paint.mNativePaint); 904 } 905 906 /** 907 * Draw the specified oval using the specified paint. The oval will be 908 * filled or framed based on the Style in the paint. 909 * 910 * @param oval The rectangle bounds of the oval to be drawn 911 */ 912 public void drawOval(RectF oval, Paint paint) { 913 if (oval == null) { 914 throw new NullPointerException(); 915 } 916 native_drawOval(mNativeCanvas, oval, paint.mNativePaint); 917 } 918 919 /** 920 * Draw the specified circle using the specified paint. If radius is <= 0, 921 * then nothing will be drawn. The circle will be filled or framed based 922 * on the Style in the paint. 923 * 924 * @param cx The x-coordinate of the center of the cirle to be drawn 925 * @param cy The y-coordinate of the center of the cirle to be drawn 926 * @param radius The radius of the cirle to be drawn 927 * @param paint The paint used to draw the circle 928 */ 929 public void drawCircle(float cx, float cy, float radius, Paint paint) { 930 native_drawCircle(mNativeCanvas, cx, cy, radius, 931 paint.mNativePaint); 932 } 933 934 /** 935 * Draw the specified arc, which will be scaled to fit inside the 936 * specified oval. If the sweep angle is >= 360, then the oval is drawn 937 * completely. Note that this differs slightly from SkPath::arcTo, which 938 * treats the sweep angle mod 360. 939 * 940 * @param oval The bounds of oval used to define the shape and size 941 * of the arc 942 * @param startAngle Starting angle (in degrees) where the arc begins 943 * @param sweepAngle Sweep angle (in degrees) measured clockwise 944 * @param useCenter If true, include the center of the oval in the arc, and 945 close it if it is being stroked. This will draw a wedge 946 * @param paint The paint used to draw the arc 947 */ 948 public void drawArc(RectF oval, float startAngle, float sweepAngle, 949 boolean useCenter, Paint paint) { 950 if (oval == null) { 951 throw new NullPointerException(); 952 } 953 native_drawArc(mNativeCanvas, oval, startAngle, sweepAngle, 954 useCenter, paint.mNativePaint); 955 } 956 957 /** 958 * Draw the specified round-rect using the specified paint. The roundrect 959 * will be filled or framed based on the Style in the paint. 960 * 961 * @param rect The rectangular bounds of the roundRect to be drawn 962 * @param rx The x-radius of the oval used to round the corners 963 * @param ry The y-radius of the oval used to round the corners 964 * @param paint The paint used to draw the roundRect 965 */ 966 public void drawRoundRect(RectF rect, float rx, float ry, Paint paint) { 967 if (rect == null) { 968 throw new NullPointerException(); 969 } 970 native_drawRoundRect(mNativeCanvas, rect, rx, ry, 971 paint.mNativePaint); 972 } 973 974 /** 975 * Draw the specified path using the specified paint. The path will be 976 * filled or framed based on the Style in the paint. 977 * 978 * @param path The path to be drawn 979 * @param paint The paint used to draw the path 980 */ 981 public void drawPath(Path path, Paint paint) { 982 native_drawPath(mNativeCanvas, path.ni(), paint.mNativePaint); 983 } 984 985 private static void throwIfRecycled(Bitmap bitmap) { 986 if (bitmap.isRecycled()) { 987 throw new RuntimeException( 988 "Canvas: trying to use a recycled bitmap " + bitmap); 989 } 990 } 991 992 /** 993 * Draw the specified bitmap, with its top/left corner at (x,y), using 994 * the specified paint, transformed by the current matrix. 995 * 996 * <p>Note: if the paint contains a maskfilter that generates a mask which 997 * extends beyond the bitmap's original width/height (e.g. BlurMaskFilter), 998 * then the bitmap will be drawn as if it were in a Shader with CLAMP mode. 999 * Thus the color outside of the original width/height will be the edge 1000 * color replicated. 1001 * 1002 * <p>If the bitmap and canvas have different densities, this function 1003 * will take care of automatically scaling the bitmap to draw at the 1004 * same density as the canvas. 1005 * 1006 * @param bitmap The bitmap to be drawn 1007 * @param left The position of the left side of the bitmap being drawn 1008 * @param top The position of the top side of the bitmap being drawn 1009 * @param paint The paint used to draw the bitmap (may be null) 1010 */ 1011 public void drawBitmap(Bitmap bitmap, float left, float top, Paint paint) { 1012 throwIfRecycled(bitmap); 1013 native_drawBitmap(mNativeCanvas, bitmap.ni(), left, top, 1014 paint != null ? paint.mNativePaint : 0, mDensity, mScreenDensity, 1015 bitmap.mDensity); 1016 } 1017 1018 /** 1019 * Draw the specified bitmap, scaling/translating automatically to fill 1020 * the destination rectangle. If the source rectangle is not null, it 1021 * specifies the subset of the bitmap to draw. 1022 * 1023 * <p>Note: if the paint contains a maskfilter that generates a mask which 1024 * extends beyond the bitmap's original width/height (e.g. BlurMaskFilter), 1025 * then the bitmap will be drawn as if it were in a Shader with CLAMP mode. 1026 * Thus the color outside of the original width/height will be the edge 1027 * color replicated. 1028 * 1029 * <p>This function <em>ignores the density associated with the bitmap</em>. 1030 * This is because the source and destination rectangle coordinate 1031 * spaces are in their respective densities, so must already have the 1032 * appropriate scaling factor applied. 1033 * 1034 * @param bitmap The bitmap to be drawn 1035 * @param src May be null. The subset of the bitmap to be drawn 1036 * @param dst The rectangle that the bitmap will be scaled/translated 1037 * to fit into 1038 * @param paint May be null. The paint used to draw the bitmap 1039 */ 1040 public void drawBitmap(Bitmap bitmap, Rect src, RectF dst, Paint paint) { 1041 if (dst == null) { 1042 throw new NullPointerException(); 1043 } 1044 throwIfRecycled(bitmap); 1045 native_drawBitmap(mNativeCanvas, bitmap.ni(), src, dst, 1046 paint != null ? paint.mNativePaint : 0, 1047 mScreenDensity, bitmap.mDensity); 1048 } 1049 1050 /** 1051 * Draw the specified bitmap, scaling/translating automatically to fill 1052 * the destination rectangle. If the source rectangle is not null, it 1053 * specifies the subset of the bitmap to draw. 1054 * 1055 * <p>Note: if the paint contains a maskfilter that generates a mask which 1056 * extends beyond the bitmap's original width/height (e.g. BlurMaskFilter), 1057 * then the bitmap will be drawn as if it were in a Shader with CLAMP mode. 1058 * Thus the color outside of the original width/height will be the edge 1059 * color replicated. 1060 * 1061 * <p>This function <em>ignores the density associated with the bitmap</em>. 1062 * This is because the source and destination rectangle coordinate 1063 * spaces are in their respective densities, so must already have the 1064 * appropriate scaling factor applied. 1065 * 1066 * @param bitmap The bitmap to be drawn 1067 * @param src May be null. The subset of the bitmap to be drawn 1068 * @param dst The rectangle that the bitmap will be scaled/translated 1069 * to fit into 1070 * @param paint May be null. The paint used to draw the bitmap 1071 */ 1072 public void drawBitmap(Bitmap bitmap, Rect src, Rect dst, Paint paint) { 1073 if (dst == null) { 1074 throw new NullPointerException(); 1075 } 1076 throwIfRecycled(bitmap); 1077 native_drawBitmap(mNativeCanvas, bitmap.ni(), src, dst, 1078 paint != null ? paint.mNativePaint : 0, 1079 mScreenDensity, bitmap.mDensity); 1080 } 1081 1082 /** 1083 * Treat the specified array of colors as a bitmap, and draw it. This gives 1084 * the same result as first creating a bitmap from the array, and then 1085 * drawing it, but this method avoids explicitly creating a bitmap object 1086 * which can be more efficient if the colors are changing often. 1087 * 1088 * @param colors Array of colors representing the pixels of the bitmap 1089 * @param offset Offset into the array of colors for the first pixel 1090 * @param stride The number of of colors in the array between rows (must be 1091 * >= width or <= -width). 1092 * @param x The X coordinate for where to draw the bitmap 1093 * @param y The Y coordinate for where to draw the bitmap 1094 * @param width The width of the bitmap 1095 * @param height The height of the bitmap 1096 * @param hasAlpha True if the alpha channel of the colors contains valid 1097 * values. If false, the alpha byte is ignored (assumed to 1098 * be 0xFF for every pixel). 1099 * @param paint May be null. The paint used to draw the bitmap 1100 */ 1101 public void drawBitmap(int[] colors, int offset, int stride, float x, 1102 float y, int width, int height, boolean hasAlpha, 1103 Paint paint) { 1104 // check for valid input 1105 if (width < 0) { 1106 throw new IllegalArgumentException("width must be >= 0"); 1107 } 1108 if (height < 0) { 1109 throw new IllegalArgumentException("height must be >= 0"); 1110 } 1111 if (Math.abs(stride) < width) { 1112 throw new IllegalArgumentException("abs(stride) must be >= width"); 1113 } 1114 int lastScanline = offset + (height - 1) * stride; 1115 int length = colors.length; 1116 if (offset < 0 || (offset + width > length) || lastScanline < 0 1117 || (lastScanline + width > length)) { 1118 throw new ArrayIndexOutOfBoundsException(); 1119 } 1120 // quick escape if there's nothing to draw 1121 if (width == 0 || height == 0) { 1122 return; 1123 } 1124 // punch down to native for the actual draw 1125 native_drawBitmap(mNativeCanvas, colors, offset, stride, x, y, width, height, hasAlpha, 1126 paint != null ? paint.mNativePaint : 0); 1127 } 1128 1129 /** Legacy version of drawBitmap(int[] colors, ...) that took ints for x,y 1130 */ 1131 public void drawBitmap(int[] colors, int offset, int stride, int x, int y, 1132 int width, int height, boolean hasAlpha, 1133 Paint paint) { 1134 // call through to the common float version 1135 drawBitmap(colors, offset, stride, (float)x, (float)y, width, height, 1136 hasAlpha, paint); 1137 } 1138 1139 /** 1140 * Draw the bitmap using the specified matrix. 1141 * 1142 * @param bitmap The bitmap to draw 1143 * @param matrix The matrix used to transform the bitmap when it is drawn 1144 * @param paint May be null. The paint used to draw the bitmap 1145 */ 1146 public void drawBitmap(Bitmap bitmap, Matrix matrix, Paint paint) { 1147 nativeDrawBitmapMatrix(mNativeCanvas, bitmap.ni(), matrix.ni(), 1148 paint != null ? paint.mNativePaint : 0); 1149 } 1150 1151 private static void checkRange(int length, int offset, int count) { 1152 if ((offset | count) < 0 || offset + count > length) { 1153 throw new ArrayIndexOutOfBoundsException(); 1154 } 1155 } 1156 1157 /** 1158 * Draw the bitmap through the mesh, where mesh vertices are evenly 1159 * distributed across the bitmap. There are meshWidth+1 vertices across, and 1160 * meshHeight+1 vertices down. The verts array is accessed in row-major 1161 * order, so that the first meshWidth+1 vertices are distributed across the 1162 * top of the bitmap from left to right. A more general version of this 1163 * methid is drawVertices(). 1164 * 1165 * @param bitmap The bitmap to draw using the mesh 1166 * @param meshWidth The number of columns in the mesh. Nothing is drawn if 1167 * this is 0 1168 * @param meshHeight The number of rows in the mesh. Nothing is drawn if 1169 * this is 0 1170 * @param verts Array of x,y pairs, specifying where the mesh should be 1171 * drawn. There must be at least 1172 * (meshWidth+1) * (meshHeight+1) * 2 + meshOffset values 1173 * in the array 1174 * @param vertOffset Number of verts elements to skip before drawing 1175 * @param colors May be null. Specifies a color at each vertex, which is 1176 * interpolated across the cell, and whose values are 1177 * multiplied by the corresponding bitmap colors. If not null, 1178 * there must be at least (meshWidth+1) * (meshHeight+1) + 1179 * colorOffset values in the array. 1180 * @param colorOffset Number of color elements to skip before drawing 1181 * @param paint May be null. The paint used to draw the bitmap 1182 */ 1183 public void drawBitmapMesh(Bitmap bitmap, int meshWidth, int meshHeight, 1184 float[] verts, int vertOffset, 1185 int[] colors, int colorOffset, Paint paint) { 1186 if ((meshWidth | meshHeight | vertOffset | colorOffset) < 0) { 1187 throw new ArrayIndexOutOfBoundsException(); 1188 } 1189 if (meshWidth == 0 || meshHeight == 0) { 1190 return; 1191 } 1192 int count = (meshWidth + 1) * (meshHeight + 1); 1193 // we mul by 2 since we need two floats per vertex 1194 checkRange(verts.length, vertOffset, count * 2); 1195 if (colors != null) { 1196 // no mul by 2, since we need only 1 color per vertex 1197 checkRange(colors.length, colorOffset, count); 1198 } 1199 nativeDrawBitmapMesh(mNativeCanvas, bitmap.ni(), meshWidth, meshHeight, 1200 verts, vertOffset, colors, colorOffset, 1201 paint != null ? paint.mNativePaint : 0); 1202 } 1203 1204 public enum VertexMode { 1205 TRIANGLES(0), 1206 TRIANGLE_STRIP(1), 1207 TRIANGLE_FAN(2); 1208 1209 VertexMode(int nativeInt) { 1210 this.nativeInt = nativeInt; 1211 } 1212 final int nativeInt; 1213 } 1214 1215 /** 1216 * Draw the array of vertices, interpreted as triangles (based on mode). The 1217 * verts array is required, and specifies the x,y pairs for each vertex. If 1218 * texs is non-null, then it is used to specify the coordinate in shader 1219 * coordinates to use at each vertex (the paint must have a shader in this 1220 * case). If there is no texs array, but there is a color array, then each 1221 * color is interpolated across its corresponding triangle in a gradient. If 1222 * both texs and colors arrays are present, then they behave as before, but 1223 * the resulting color at each pixels is the result of multiplying the 1224 * colors from the shader and the color-gradient together. The indices array 1225 * is optional, but if it is present, then it is used to specify the index 1226 * of each triangle, rather than just walking through the arrays in order. 1227 * 1228 * @param mode How to interpret the array of vertices 1229 * @param vertexCount The number of values in the vertices array (and 1230 * corresponding texs and colors arrays if non-null). Each logical 1231 * vertex is two values (x, y), vertexCount must be a multiple of 2. 1232 * @param verts Array of vertices for the mesh 1233 * @param vertOffset Number of values in the verts to skip before drawing. 1234 * @param texs May be null. If not null, specifies the coordinates to sample 1235 * into the current shader (e.g. bitmap tile or gradient) 1236 * @param texOffset Number of values in texs to skip before drawing. 1237 * @param colors May be null. If not null, specifies a color for each 1238 * vertex, to be interpolated across the triangle. 1239 * @param colorOffset Number of values in colors to skip before drawing. 1240 * @param indices If not null, array of indices to reference into the 1241 * vertex (texs, colors) array. 1242 * @param indexCount number of entries in the indices array (if not null). 1243 * @param paint Specifies the shader to use if the texs array is non-null. 1244 */ 1245 public void drawVertices(VertexMode mode, int vertexCount, 1246 float[] verts, int vertOffset, 1247 float[] texs, int texOffset, 1248 int[] colors, int colorOffset, 1249 short[] indices, int indexOffset, 1250 int indexCount, Paint paint) { 1251 checkRange(verts.length, vertOffset, vertexCount); 1252 if (texs != null) { 1253 checkRange(texs.length, texOffset, vertexCount); 1254 } 1255 if (colors != null) { 1256 checkRange(colors.length, colorOffset, vertexCount / 2); 1257 } 1258 if (indices != null) { 1259 checkRange(indices.length, indexOffset, indexCount); 1260 } 1261 nativeDrawVertices(mNativeCanvas, mode.nativeInt, vertexCount, verts, 1262 vertOffset, texs, texOffset, colors, colorOffset, 1263 indices, indexOffset, indexCount, paint.mNativePaint); 1264 } 1265 1266 /** 1267 * Draw the text, with origin at (x,y), using the specified paint. The 1268 * origin is interpreted based on the Align setting in the paint. 1269 * 1270 * @param text The text to be drawn 1271 * @param x The x-coordinate of the origin of the text being drawn 1272 * @param y The y-coordinate of the origin of the text being drawn 1273 * @param paint The paint used for the text (e.g. color, size, style) 1274 */ 1275 public void drawText(char[] text, int index, int count, float x, float y, 1276 Paint paint) { 1277 if ((index | count | (index + count) | 1278 (text.length - index - count)) < 0) { 1279 throw new IndexOutOfBoundsException(); 1280 } 1281 native_drawText(mNativeCanvas, text, index, count, x, y, paint.mBidiFlags, 1282 paint.mNativePaint); 1283 } 1284 1285 /** 1286 * Draw the text, with origin at (x,y), using the specified paint. The 1287 * origin is interpreted based on the Align setting in the paint. 1288 * 1289 * @param text The text to be drawn 1290 * @param x The x-coordinate of the origin of the text being drawn 1291 * @param y The y-coordinate of the origin of the text being drawn 1292 * @param paint The paint used for the text (e.g. color, size, style) 1293 */ 1294 public void drawText(String text, float x, float y, Paint paint) { 1295 native_drawText(mNativeCanvas, text, 0, text.length(), x, y, paint.mBidiFlags, 1296 paint.mNativePaint); 1297 } 1298 1299 /** 1300 * Draw the text, with origin at (x,y), using the specified paint. 1301 * The origin is interpreted based on the Align setting in the paint. 1302 * 1303 * @param text The text to be drawn 1304 * @param start The index of the first character in text to draw 1305 * @param end (end - 1) is the index of the last character in text to draw 1306 * @param x The x-coordinate of the origin of the text being drawn 1307 * @param y The y-coordinate of the origin of the text being drawn 1308 * @param paint The paint used for the text (e.g. color, size, style) 1309 */ 1310 public void drawText(String text, int start, int end, float x, float y, 1311 Paint paint) { 1312 if ((start | end | (end - start) | (text.length() - end)) < 0) { 1313 throw new IndexOutOfBoundsException(); 1314 } 1315 native_drawText(mNativeCanvas, text, start, end, x, y, paint.mBidiFlags, 1316 paint.mNativePaint); 1317 } 1318 1319 /** 1320 * Draw the specified range of text, specified by start/end, with its 1321 * origin at (x,y), in the specified Paint. The origin is interpreted 1322 * based on the Align setting in the Paint. 1323 * 1324 * @param text The text to be drawn 1325 * @param start The index of the first character in text to draw 1326 * @param end (end - 1) is the index of the last character in text 1327 * to draw 1328 * @param x The x-coordinate of origin for where to draw the text 1329 * @param y The y-coordinate of origin for where to draw the text 1330 * @param paint The paint used for the text (e.g. color, size, style) 1331 */ 1332 public void drawText(CharSequence text, int start, int end, float x, 1333 float y, Paint paint) { 1334 if (text instanceof String || text instanceof SpannedString || 1335 text instanceof SpannableString) { 1336 native_drawText(mNativeCanvas, text.toString(), start, end, x, y, 1337 paint.mBidiFlags, paint.mNativePaint); 1338 } else if (text instanceof GraphicsOperations) { 1339 ((GraphicsOperations) text).drawText(this, start, end, x, y, 1340 paint); 1341 } else { 1342 char[] buf = TemporaryBuffer.obtain(end - start); 1343 TextUtils.getChars(text, start, end, buf, 0); 1344 native_drawText(mNativeCanvas, buf, 0, end - start, x, y, 1345 paint.mBidiFlags, paint.mNativePaint); 1346 TemporaryBuffer.recycle(buf); 1347 } 1348 } 1349 1350 /** 1351 * Render a run of all LTR or all RTL text, with shaping. This does not run 1352 * bidi on the provided text, but renders it as a uniform right-to-left or 1353 * left-to-right run, as indicated by dir. Alignment of the text is as 1354 * determined by the Paint's TextAlign value. 1355 * 1356 * @param text the text to render 1357 * @param index the start of the text to render 1358 * @param count the count of chars to render 1359 * @param contextIndex the start of the context for shaping. Must be 1360 * no greater than index. 1361 * @param contextCount the number of characters in the context for shaping. 1362 * ContexIndex + contextCount must be no less than index 1363 * + count. 1364 * @param x the x position at which to draw the text 1365 * @param y the y position at which to draw the text 1366 * @param dir the run direction, either {@link #DIRECTION_LTR} or 1367 * {@link #DIRECTION_RTL}. 1368 * @param paint the paint 1369 * @hide 1370 */ 1371 public void drawTextRun(char[] text, int index, int count, 1372 int contextIndex, int contextCount, float x, float y, int dir, 1373 Paint paint) { 1374 1375 if (text == null) { 1376 throw new NullPointerException("text is null"); 1377 } 1378 if (paint == null) { 1379 throw new NullPointerException("paint is null"); 1380 } 1381 if ((index | count | text.length - index - count) < 0) { 1382 throw new IndexOutOfBoundsException(); 1383 } 1384 if (dir != DIRECTION_LTR && dir != DIRECTION_RTL) { 1385 throw new IllegalArgumentException("unknown dir: " + dir); 1386 } 1387 1388 native_drawTextRun(mNativeCanvas, text, index, count, 1389 contextIndex, contextCount, x, y, dir, paint.mNativePaint); 1390 } 1391 1392 /** 1393 * Render a run of all LTR or all RTL text, with shaping. This does not run 1394 * bidi on the provided text, but renders it as a uniform right-to-left or 1395 * left-to-right run, as indicated by dir. Alignment of the text is as 1396 * determined by the Paint's TextAlign value. 1397 * 1398 * @param text the text to render 1399 * @param start the start of the text to render. Data before this position 1400 * can be used for shaping context. 1401 * @param end the end of the text to render. Data at or after this 1402 * position can be used for shaping context. 1403 * @param x the x position at which to draw the text 1404 * @param y the y position at which to draw the text 1405 * @param dir the run direction, either 0 for LTR or 1 for RTL. 1406 * @param paint the paint 1407 * @hide 1408 */ 1409 public void drawTextRun(CharSequence text, int start, int end, 1410 int contextStart, int contextEnd, float x, float y, int dir, 1411 Paint paint) { 1412 1413 if (text == null) { 1414 throw new NullPointerException("text is null"); 1415 } 1416 if (paint == null) { 1417 throw new NullPointerException("paint is null"); 1418 } 1419 if ((start | end | end - start | text.length() - end) < 0) { 1420 throw new IndexOutOfBoundsException(); 1421 } 1422 1423 int flags = dir == 0 ? 0 : 1; 1424 1425 if (text instanceof String || text instanceof SpannedString || 1426 text instanceof SpannableString) { 1427 native_drawTextRun(mNativeCanvas, text.toString(), start, end, 1428 contextStart, contextEnd, x, y, flags, paint.mNativePaint); 1429 } else if (text instanceof GraphicsOperations) { 1430 ((GraphicsOperations) text).drawTextRun(this, start, end, 1431 contextStart, contextEnd, x, y, flags, paint); 1432 } else { 1433 int contextLen = contextEnd - contextStart; 1434 int len = end - start; 1435 char[] buf = TemporaryBuffer.obtain(contextLen); 1436 TextUtils.getChars(text, contextStart, contextEnd, buf, 0); 1437 native_drawTextRun(mNativeCanvas, buf, start - contextStart, len, 1438 0, contextLen, x, y, flags, paint.mNativePaint); 1439 TemporaryBuffer.recycle(buf); 1440 } 1441 } 1442 1443 /** 1444 * Draw the text in the array, with each character's origin specified by 1445 * the pos array. 1446 * 1447 * @param text The text to be drawn 1448 * @param index The index of the first character to draw 1449 * @param count The number of characters to draw, starting from index. 1450 * @param pos Array of [x,y] positions, used to position each 1451 * character 1452 * @param paint The paint used for the text (e.g. color, size, style) 1453 */ 1454 public void drawPosText(char[] text, int index, int count, float[] pos, 1455 Paint paint) { 1456 if (index < 0 || index + count > text.length || count*2 > pos.length) { 1457 throw new IndexOutOfBoundsException(); 1458 } 1459 native_drawPosText(mNativeCanvas, text, index, count, pos, 1460 paint.mNativePaint); 1461 } 1462 1463 /** 1464 * Draw the text in the array, with each character's origin specified by 1465 * the pos array. 1466 * 1467 * @param text The text to be drawn 1468 * @param pos Array of [x,y] positions, used to position each character 1469 * @param paint The paint used for the text (e.g. color, size, style) 1470 */ 1471 public void drawPosText(String text, float[] pos, Paint paint) { 1472 if (text.length()*2 > pos.length) { 1473 throw new ArrayIndexOutOfBoundsException(); 1474 } 1475 native_drawPosText(mNativeCanvas, text, pos, paint.mNativePaint); 1476 } 1477 1478 /** 1479 * Draw the text, with origin at (x,y), using the specified paint, along 1480 * the specified path. The paint's Align setting determins where along the 1481 * path to start the text. 1482 * 1483 * @param text The text to be drawn 1484 * @param path The path the text should follow for its baseline 1485 * @param hOffset The distance along the path to add to the text's 1486 * starting position 1487 * @param vOffset The distance above(-) or below(+) the path to position 1488 * the text 1489 * @param paint The paint used for the text (e.g. color, size, style) 1490 */ 1491 public void drawTextOnPath(char[] text, int index, int count, Path path, 1492 float hOffset, float vOffset, Paint paint) { 1493 if (index < 0 || index + count > text.length) { 1494 throw new ArrayIndexOutOfBoundsException(); 1495 } 1496 native_drawTextOnPath(mNativeCanvas, text, index, count, 1497 path.ni(), hOffset, vOffset, 1498 paint.mNativePaint); 1499 } 1500 1501 /** 1502 * Draw the text, with origin at (x,y), using the specified paint, along 1503 * the specified path. The paint's Align setting determins where along the 1504 * path to start the text. 1505 * 1506 * @param text The text to be drawn 1507 * @param path The path the text should follow for its baseline 1508 * @param hOffset The distance along the path to add to the text's 1509 * starting position 1510 * @param vOffset The distance above(-) or below(+) the path to position 1511 * the text 1512 * @param paint The paint used for the text (e.g. color, size, style) 1513 */ 1514 public void drawTextOnPath(String text, Path path, float hOffset, 1515 float vOffset, Paint paint) { 1516 if (text.length() > 0) { 1517 native_drawTextOnPath(mNativeCanvas, text, path.ni(), 1518 hOffset, vOffset, paint.mNativePaint); 1519 } 1520 } 1521 1522 /** 1523 * Save the canvas state, draw the picture, and restore the canvas state. 1524 * This differs from picture.draw(canvas), which does not perform any 1525 * save/restore. 1526 * 1527 * @param picture The picture to be drawn 1528 */ 1529 public void drawPicture(Picture picture) { 1530 picture.endRecording(); 1531 native_drawPicture(mNativeCanvas, picture.ni()); 1532 } 1533 1534 /** 1535 * Draw the picture, stretched to fit into the dst rectangle. 1536 */ 1537 public void drawPicture(Picture picture, RectF dst) { 1538 save(); 1539 translate(dst.left, dst.top); 1540 if (picture.getWidth() > 0 && picture.getHeight() > 0) { 1541 scale(dst.width() / picture.getWidth(), 1542 dst.height() / picture.getHeight()); 1543 } 1544 drawPicture(picture); 1545 restore(); 1546 } 1547 1548 /** 1549 * Draw the picture, stretched to fit into the dst rectangle. 1550 */ 1551 public void drawPicture(Picture picture, Rect dst) { 1552 save(); 1553 translate(dst.left, dst.top); 1554 if (picture.getWidth() > 0 && picture.getHeight() > 0) { 1555 scale((float)dst.width() / picture.getWidth(), 1556 (float)dst.height() / picture.getHeight()); 1557 } 1558 drawPicture(picture); 1559 restore(); 1560 } 1561 1562 protected void finalize() throws Throwable { 1563 super.finalize(); 1564 // If the constructor threw an exception before setting mNativeCanvas, the native finalizer 1565 // must not be invoked. 1566 if (mNativeCanvas != 0) { 1567 finalizer(mNativeCanvas); 1568 } 1569 } 1570 1571 /** 1572 * Free up as much memory as possible from private caches (e.g. fonts, 1573 * images) 1574 * 1575 * @hide - for now 1576 */ 1577 public static native void freeCaches(); 1578 1579 private static native int initRaster(int nativeBitmapOrZero); 1580 private static native int initGL(); 1581 private static native void native_setBitmap(int nativeCanvas, int bitmap); 1582 private static native void nativeSetViewport(int nCanvas, int w, int h); 1583 private static native int native_saveLayer(int nativeCanvas, RectF bounds, 1584 int paint, int layerFlags); 1585 private static native int native_saveLayer(int nativeCanvas, float l, 1586 float t, float r, float b, 1587 int paint, int layerFlags); 1588 private static native int native_saveLayerAlpha(int nativeCanvas, 1589 RectF bounds, int alpha, 1590 int layerFlags); 1591 private static native int native_saveLayerAlpha(int nativeCanvas, float l, 1592 float t, float r, float b, 1593 int alpha, int layerFlags); 1594 1595 private static native void native_concat(int nCanvas, int nMatrix); 1596 private static native void native_setMatrix(int nCanvas, int nMatrix); 1597 private static native boolean native_clipRect(int nCanvas, 1598 float left, float top, 1599 float right, float bottom, 1600 int regionOp); 1601 private static native boolean native_clipPath(int nativeCanvas, 1602 int nativePath, 1603 int regionOp); 1604 private static native boolean native_clipRegion(int nativeCanvas, 1605 int nativeRegion, 1606 int regionOp); 1607 private static native void nativeSetDrawFilter(int nativeCanvas, 1608 int nativeFilter); 1609 private static native boolean native_getClipBounds(int nativeCanvas, 1610 Rect bounds); 1611 private static native void native_getCTM(int canvas, int matrix); 1612 private static native boolean native_quickReject(int nativeCanvas, 1613 RectF rect, 1614 int native_edgeType); 1615 private static native boolean native_quickReject(int nativeCanvas, 1616 int path, 1617 int native_edgeType); 1618 private static native boolean native_quickReject(int nativeCanvas, 1619 float left, float top, 1620 float right, float bottom, 1621 int native_edgeType); 1622 private static native void native_drawRGB(int nativeCanvas, int r, int g, 1623 int b); 1624 private static native void native_drawARGB(int nativeCanvas, int a, int r, 1625 int g, int b); 1626 private static native void native_drawColor(int nativeCanvas, int color); 1627 private static native void native_drawColor(int nativeCanvas, int color, 1628 int mode); 1629 private static native void native_drawPaint(int nativeCanvas, int paint); 1630 private static native void native_drawLine(int nativeCanvas, float startX, 1631 float startY, float stopX, 1632 float stopY, int paint); 1633 private static native void native_drawRect(int nativeCanvas, RectF rect, 1634 int paint); 1635 private static native void native_drawRect(int nativeCanvas, float left, 1636 float top, float right, 1637 float bottom, int paint); 1638 private static native void native_drawOval(int nativeCanvas, RectF oval, 1639 int paint); 1640 private static native void native_drawCircle(int nativeCanvas, float cx, 1641 float cy, float radius, 1642 int paint); 1643 private static native void native_drawArc(int nativeCanvas, RectF oval, 1644 float startAngle, float sweep, 1645 boolean useCenter, int paint); 1646 private static native void native_drawRoundRect(int nativeCanvas, 1647 RectF rect, float rx, 1648 float ry, int paint); 1649 private static native void native_drawPath(int nativeCanvas, int path, 1650 int paint); 1651 private native void native_drawBitmap(int nativeCanvas, int bitmap, 1652 float left, float top, 1653 int nativePaintOrZero, 1654 int canvasDensity, 1655 int screenDensity, 1656 int bitmapDensity); 1657 private native void native_drawBitmap(int nativeCanvas, int bitmap, 1658 Rect src, RectF dst, 1659 int nativePaintOrZero, 1660 int screenDensity, 1661 int bitmapDensity); 1662 private static native void native_drawBitmap(int nativeCanvas, int bitmap, 1663 Rect src, Rect dst, 1664 int nativePaintOrZero, 1665 int screenDensity, 1666 int bitmapDensity); 1667 private static native void native_drawBitmap(int nativeCanvas, int[] colors, 1668 int offset, int stride, float x, 1669 float y, int width, int height, 1670 boolean hasAlpha, 1671 int nativePaintOrZero); 1672 private static native void nativeDrawBitmapMatrix(int nCanvas, int nBitmap, 1673 int nMatrix, int nPaint); 1674 private static native void nativeDrawBitmapMesh(int nCanvas, int nBitmap, 1675 int meshWidth, int meshHeight, 1676 float[] verts, int vertOffset, 1677 int[] colors, int colorOffset, int nPaint); 1678 private static native void nativeDrawVertices(int nCanvas, int mode, int n, 1679 float[] verts, int vertOffset, float[] texs, int texOffset, 1680 int[] colors, int colorOffset, short[] indices, 1681 int indexOffset, int indexCount, int nPaint); 1682 1683 private static native void native_drawText(int nativeCanvas, char[] text, 1684 int index, int count, float x, 1685 float y, int flags, int paint); 1686 private static native void native_drawText(int nativeCanvas, String text, 1687 int start, int end, float x, 1688 float y, int flags, int paint); 1689 1690 private static native void native_drawTextRun(int nativeCanvas, String text, 1691 int start, int end, int contextStart, int contextEnd, 1692 float x, float y, int flags, int paint); 1693 1694 private static native void native_drawTextRun(int nativeCanvas, char[] text, 1695 int start, int count, int contextStart, int contextCount, 1696 float x, float y, int flags, int paint); 1697 1698 private static native void native_drawPosText(int nativeCanvas, 1699 char[] text, int index, 1700 int count, float[] pos, 1701 int paint); 1702 private static native void native_drawPosText(int nativeCanvas, 1703 String text, float[] pos, 1704 int paint); 1705 private static native void native_drawTextOnPath(int nativeCanvas, 1706 char[] text, int index, 1707 int count, int path, 1708 float hOffset, 1709 float vOffset, int paint); 1710 private static native void native_drawTextOnPath(int nativeCanvas, 1711 String text, int path, 1712 float hOffset, 1713 float vOffset, int paint); 1714 private static native void native_drawPicture(int nativeCanvas, 1715 int nativePicture); 1716 private static native void finalizer(int nativeCanvas); 1717} 1718