Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2010 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | package android.text; |
| 18 | |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 19 | import android.graphics.Bitmap; |
| 20 | import android.graphics.Canvas; |
| 21 | import android.graphics.Paint; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 22 | import android.graphics.Paint.FontMetricsInt; |
Gilles Debunne | cc3ec6c | 2010-06-23 10:30:27 -0700 | [diff] [blame] | 23 | import android.graphics.RectF; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 24 | import android.text.Layout.Directions; |
Doug Felt | c982f60 | 2010-05-25 11:51:40 -0700 | [diff] [blame] | 25 | import android.text.Layout.TabStops; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 26 | import android.text.style.CharacterStyle; |
| 27 | import android.text.style.MetricAffectingSpan; |
| 28 | import android.text.style.ReplacementSpan; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 29 | import android.util.Log; |
| 30 | |
Gilles Debunne | dd8f5ed | 2011-08-10 18:25:49 -0700 | [diff] [blame] | 31 | import com.android.internal.util.ArrayUtils; |
| 32 | |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 33 | /** |
| 34 | * Represents a line of styled text, for measuring in visual order and |
| 35 | * for rendering. |
| 36 | * |
| 37 | * <p>Get a new instance using obtain(), and when finished with it, return it |
| 38 | * to the pool using recycle(). |
| 39 | * |
| 40 | * <p>Call set to prepare the instance for use, then either draw, measure, |
| 41 | * metrics, or caretToLeftRightOf. |
| 42 | * |
| 43 | * @hide |
| 44 | */ |
| 45 | class TextLine { |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 46 | private static final boolean DEBUG = false; |
| 47 | |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 48 | private TextPaint mPaint; |
| 49 | private CharSequence mText; |
| 50 | private int mStart; |
| 51 | private int mLen; |
| 52 | private int mDir; |
| 53 | private Directions mDirections; |
| 54 | private boolean mHasTabs; |
Doug Felt | c982f60 | 2010-05-25 11:51:40 -0700 | [diff] [blame] | 55 | private TabStops mTabs; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 56 | private char[] mChars; |
| 57 | private boolean mCharsValid; |
| 58 | private Spanned mSpanned; |
Gilles Debunne | 345cb03 | 2010-06-16 17:13:23 -0700 | [diff] [blame] | 59 | private final TextPaint mWorkPaint = new TextPaint(); |
Gilles Debunne | c1f4483 | 2011-12-08 16:03:00 -0800 | [diff] [blame] | 60 | private final SpanSet<MetricAffectingSpan> mMetricAffectingSpanSpanSet = |
| 61 | new SpanSet<MetricAffectingSpan>(MetricAffectingSpan.class); |
| 62 | private final SpanSet<CharacterStyle> mCharacterStyleSpanSet = |
| 63 | new SpanSet<CharacterStyle>(CharacterStyle.class); |
| 64 | private final SpanSet<ReplacementSpan> mReplacementSpanSpanSet = |
| 65 | new SpanSet<ReplacementSpan>(ReplacementSpan.class); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 66 | |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 67 | private static final TextLine[] sCached = new TextLine[3]; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 68 | |
| 69 | /** |
| 70 | * Returns a new TextLine from the shared pool. |
| 71 | * |
| 72 | * @return an uninitialized TextLine |
| 73 | */ |
| 74 | static TextLine obtain() { |
| 75 | TextLine tl; |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 76 | synchronized (sCached) { |
| 77 | for (int i = sCached.length; --i >= 0;) { |
| 78 | if (sCached[i] != null) { |
| 79 | tl = sCached[i]; |
| 80 | sCached[i] = null; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 81 | return tl; |
| 82 | } |
| 83 | } |
| 84 | } |
| 85 | tl = new TextLine(); |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 86 | if (DEBUG) { |
| 87 | Log.v("TLINE", "new: " + tl); |
| 88 | } |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 89 | return tl; |
| 90 | } |
| 91 | |
| 92 | /** |
| 93 | * Puts a TextLine back into the shared pool. Do not use this TextLine once |
| 94 | * it has been returned. |
| 95 | * @param tl the textLine |
| 96 | * @return null, as a convenience from clearing references to the provided |
| 97 | * TextLine |
| 98 | */ |
| 99 | static TextLine recycle(TextLine tl) { |
| 100 | tl.mText = null; |
| 101 | tl.mPaint = null; |
| 102 | tl.mDirections = null; |
Gilles Debunne | c3fb7a1 | 2011-12-12 14:03:40 -0800 | [diff] [blame] | 103 | |
| 104 | tl.mMetricAffectingSpanSpanSet.recycle(); |
| 105 | tl.mCharacterStyleSpanSet.recycle(); |
| 106 | tl.mReplacementSpanSpanSet.recycle(); |
| 107 | |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 108 | synchronized(sCached) { |
| 109 | for (int i = 0; i < sCached.length; ++i) { |
| 110 | if (sCached[i] == null) { |
| 111 | sCached[i] = tl; |
Gilles Debunne | f902d7b | 2011-01-25 09:09:46 -0800 | [diff] [blame] | 112 | break; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 113 | } |
| 114 | } |
| 115 | } |
| 116 | return null; |
| 117 | } |
| 118 | |
| 119 | /** |
| 120 | * Initializes a TextLine and prepares it for use. |
| 121 | * |
| 122 | * @param paint the base paint for the line |
| 123 | * @param text the text, can be Styled |
| 124 | * @param start the start of the line relative to the text |
| 125 | * @param limit the limit of the line relative to the text |
| 126 | * @param dir the paragraph direction of this line |
| 127 | * @param directions the directions information of this line |
| 128 | * @param hasTabs true if the line might contain tabs or emoji |
Doug Felt | c982f60 | 2010-05-25 11:51:40 -0700 | [diff] [blame] | 129 | * @param tabStops the tabStops. Can be null. |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 130 | */ |
| 131 | void set(TextPaint paint, CharSequence text, int start, int limit, int dir, |
Doug Felt | c982f60 | 2010-05-25 11:51:40 -0700 | [diff] [blame] | 132 | Directions directions, boolean hasTabs, TabStops tabStops) { |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 133 | mPaint = paint; |
| 134 | mText = text; |
| 135 | mStart = start; |
| 136 | mLen = limit - start; |
| 137 | mDir = dir; |
| 138 | mDirections = directions; |
Fabrice Di Meglio | 8059e090 | 2011-08-10 16:31:58 -0700 | [diff] [blame] | 139 | if (mDirections == null) { |
| 140 | throw new IllegalArgumentException("Directions cannot be null"); |
| 141 | } |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 142 | mHasTabs = hasTabs; |
| 143 | mSpanned = null; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 144 | |
| 145 | boolean hasReplacement = false; |
| 146 | if (text instanceof Spanned) { |
| 147 | mSpanned = (Spanned) text; |
Gilles Debunne | c1f4483 | 2011-12-08 16:03:00 -0800 | [diff] [blame] | 148 | mReplacementSpanSpanSet.init(mSpanned, start, limit); |
| 149 | hasReplacement = mReplacementSpanSpanSet.numberOfSpans > 0; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 150 | } |
| 151 | |
Gilles Debunne | 1e3ac18 | 2011-03-08 14:22:34 -0800 | [diff] [blame] | 152 | mCharsValid = hasReplacement || hasTabs || directions != Layout.DIRS_ALL_LEFT_TO_RIGHT; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 153 | |
| 154 | if (mCharsValid) { |
| 155 | if (mChars == null || mChars.length < mLen) { |
| 156 | mChars = new char[ArrayUtils.idealCharArraySize(mLen)]; |
| 157 | } |
| 158 | TextUtils.getChars(text, start, limit, mChars, 0); |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 159 | if (hasReplacement) { |
| 160 | // Handle these all at once so we don't have to do it as we go. |
| 161 | // Replace the first character of each replacement run with the |
| 162 | // object-replacement character and the remainder with zero width |
| 163 | // non-break space aka BOM. Cursor movement code skips these |
| 164 | // zero-width characters. |
| 165 | char[] chars = mChars; |
| 166 | for (int i = start, inext; i < limit; i = inext) { |
Gilles Debunne | c1f4483 | 2011-12-08 16:03:00 -0800 | [diff] [blame] | 167 | inext = mReplacementSpanSpanSet.getNextTransition(i, limit); |
| 168 | if (mReplacementSpanSpanSet.hasSpansIntersecting(i, inext)) { |
Gilles Debunne | 1e3ac18 | 2011-03-08 14:22:34 -0800 | [diff] [blame] | 169 | // transition into a span |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 170 | chars[i - start] = '\ufffc'; |
| 171 | for (int j = i - start + 1, e = inext - start; j < e; ++j) { |
| 172 | chars[j] = '\ufeff'; // used as ZWNBS, marks positions to skip |
| 173 | } |
| 174 | } |
| 175 | } |
| 176 | } |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 177 | } |
Doug Felt | c982f60 | 2010-05-25 11:51:40 -0700 | [diff] [blame] | 178 | mTabs = tabStops; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 179 | } |
| 180 | |
| 181 | /** |
| 182 | * Renders the TextLine. |
| 183 | * |
| 184 | * @param c the canvas to render on |
| 185 | * @param x the leading margin position |
| 186 | * @param top the top of the line |
| 187 | * @param y the baseline |
| 188 | * @param bottom the bottom of the line |
| 189 | */ |
| 190 | void draw(Canvas c, float x, int top, int y, int bottom) { |
| 191 | if (!mHasTabs) { |
| 192 | if (mDirections == Layout.DIRS_ALL_LEFT_TO_RIGHT) { |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 193 | drawRun(c, 0, mLen, false, x, top, y, bottom, false); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 194 | return; |
| 195 | } |
| 196 | if (mDirections == Layout.DIRS_ALL_RIGHT_TO_LEFT) { |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 197 | drawRun(c, 0, mLen, true, x, top, y, bottom, false); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 198 | return; |
| 199 | } |
| 200 | } |
| 201 | |
| 202 | float h = 0; |
| 203 | int[] runs = mDirections.mDirections; |
| 204 | RectF emojiRect = null; |
| 205 | |
| 206 | int lastRunIndex = runs.length - 2; |
| 207 | for (int i = 0; i < runs.length; i += 2) { |
| 208 | int runStart = runs[i]; |
| 209 | int runLimit = runStart + (runs[i+1] & Layout.RUN_LENGTH_MASK); |
| 210 | if (runLimit > mLen) { |
| 211 | runLimit = mLen; |
| 212 | } |
| 213 | boolean runIsRtl = (runs[i+1] & Layout.RUN_RTL_FLAG) != 0; |
| 214 | |
| 215 | int segstart = runStart; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 216 | for (int j = mHasTabs ? runStart : runLimit; j <= runLimit; j++) { |
| 217 | int codept = 0; |
| 218 | Bitmap bm = null; |
| 219 | |
| 220 | if (mHasTabs && j < runLimit) { |
| 221 | codept = mChars[j]; |
| 222 | if (codept >= 0xd800 && codept < 0xdc00 && j + 1 < runLimit) { |
| 223 | codept = Character.codePointAt(mChars, j); |
| 224 | if (codept >= Layout.MIN_EMOJI && codept <= Layout.MAX_EMOJI) { |
| 225 | bm = Layout.EMOJI_FACTORY.getBitmapFromAndroidPua(codept); |
| 226 | } else if (codept > 0xffff) { |
| 227 | ++j; |
| 228 | continue; |
| 229 | } |
| 230 | } |
| 231 | } |
| 232 | |
| 233 | if (j == runLimit || codept == '\t' || bm != null) { |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 234 | h += drawRun(c, segstart, j, runIsRtl, x+h, top, y, bottom, |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 235 | i != lastRunIndex || j != mLen); |
| 236 | |
| 237 | if (codept == '\t') { |
| 238 | h = mDir * nextTab(h * mDir); |
| 239 | } else if (bm != null) { |
| 240 | float bmAscent = ascent(j); |
| 241 | float bitmapHeight = bm.getHeight(); |
| 242 | float scale = -bmAscent / bitmapHeight; |
| 243 | float width = bm.getWidth() * scale; |
| 244 | |
| 245 | if (emojiRect == null) { |
| 246 | emojiRect = new RectF(); |
| 247 | } |
| 248 | emojiRect.set(x + h, y + bmAscent, |
| 249 | x + h + width, y); |
| 250 | c.drawBitmap(bm, null, emojiRect, mPaint); |
| 251 | h += width; |
| 252 | j++; |
| 253 | } |
| 254 | segstart = j + 1; |
| 255 | } |
| 256 | } |
| 257 | } |
| 258 | } |
| 259 | |
| 260 | /** |
| 261 | * Returns metrics information for the entire line. |
| 262 | * |
| 263 | * @param fmi receives font metrics information, can be null |
| 264 | * @return the signed width of the line |
| 265 | */ |
| 266 | float metrics(FontMetricsInt fmi) { |
| 267 | return measure(mLen, false, fmi); |
| 268 | } |
| 269 | |
| 270 | /** |
| 271 | * Returns information about a position on the line. |
| 272 | * |
| 273 | * @param offset the line-relative character offset, between 0 and the |
| 274 | * line length, inclusive |
| 275 | * @param trailing true to measure the trailing edge of the character |
| 276 | * before offset, false to measure the leading edge of the character |
| 277 | * at offset. |
| 278 | * @param fmi receives metrics information about the requested |
| 279 | * character, can be null. |
| 280 | * @return the signed offset from the leading margin to the requested |
| 281 | * character edge. |
| 282 | */ |
| 283 | float measure(int offset, boolean trailing, FontMetricsInt fmi) { |
| 284 | int target = trailing ? offset - 1 : offset; |
| 285 | if (target < 0) { |
| 286 | return 0; |
| 287 | } |
| 288 | |
| 289 | float h = 0; |
| 290 | |
| 291 | if (!mHasTabs) { |
| 292 | if (mDirections == Layout.DIRS_ALL_LEFT_TO_RIGHT) { |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 293 | return measureRun(0, offset, mLen, false, fmi); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 294 | } |
| 295 | if (mDirections == Layout.DIRS_ALL_RIGHT_TO_LEFT) { |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 296 | return measureRun(0, offset, mLen, true, fmi); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 297 | } |
| 298 | } |
| 299 | |
| 300 | char[] chars = mChars; |
| 301 | int[] runs = mDirections.mDirections; |
| 302 | for (int i = 0; i < runs.length; i += 2) { |
| 303 | int runStart = runs[i]; |
| 304 | int runLimit = runStart + (runs[i+1] & Layout.RUN_LENGTH_MASK); |
| 305 | if (runLimit > mLen) { |
| 306 | runLimit = mLen; |
| 307 | } |
| 308 | boolean runIsRtl = (runs[i+1] & Layout.RUN_RTL_FLAG) != 0; |
| 309 | |
| 310 | int segstart = runStart; |
| 311 | for (int j = mHasTabs ? runStart : runLimit; j <= runLimit; j++) { |
| 312 | int codept = 0; |
| 313 | Bitmap bm = null; |
| 314 | |
| 315 | if (mHasTabs && j < runLimit) { |
| 316 | codept = chars[j]; |
| 317 | if (codept >= 0xd800 && codept < 0xdc00 && j + 1 < runLimit) { |
| 318 | codept = Character.codePointAt(chars, j); |
| 319 | if (codept >= Layout.MIN_EMOJI && codept <= Layout.MAX_EMOJI) { |
| 320 | bm = Layout.EMOJI_FACTORY.getBitmapFromAndroidPua(codept); |
| 321 | } else if (codept > 0xffff) { |
| 322 | ++j; |
| 323 | continue; |
| 324 | } |
| 325 | } |
| 326 | } |
| 327 | |
| 328 | if (j == runLimit || codept == '\t' || bm != null) { |
| 329 | boolean inSegment = target >= segstart && target < j; |
| 330 | |
| 331 | boolean advance = (mDir == Layout.DIR_RIGHT_TO_LEFT) == runIsRtl; |
| 332 | if (inSegment && advance) { |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 333 | return h += measureRun(segstart, offset, j, runIsRtl, fmi); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 334 | } |
| 335 | |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 336 | float w = measureRun(segstart, j, j, runIsRtl, fmi); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 337 | h += advance ? w : -w; |
| 338 | |
| 339 | if (inSegment) { |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 340 | return h += measureRun(segstart, offset, j, runIsRtl, null); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 341 | } |
| 342 | |
| 343 | if (codept == '\t') { |
| 344 | if (offset == j) { |
| 345 | return h; |
| 346 | } |
| 347 | h = mDir * nextTab(h * mDir); |
| 348 | if (target == j) { |
| 349 | return h; |
| 350 | } |
| 351 | } |
| 352 | |
| 353 | if (bm != null) { |
| 354 | float bmAscent = ascent(j); |
| 355 | float wid = bm.getWidth() * -bmAscent / bm.getHeight(); |
| 356 | h += mDir * wid; |
| 357 | j++; |
| 358 | } |
| 359 | |
| 360 | segstart = j + 1; |
| 361 | } |
| 362 | } |
| 363 | } |
| 364 | |
| 365 | return h; |
| 366 | } |
| 367 | |
| 368 | /** |
| 369 | * Draws a unidirectional (but possibly multi-styled) run of text. |
| 370 | * |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 371 | * |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 372 | * @param c the canvas to draw on |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 373 | * @param start the line-relative start |
| 374 | * @param limit the line-relative limit |
| 375 | * @param runIsRtl true if the run is right-to-left |
| 376 | * @param x the position of the run that is closest to the leading margin |
| 377 | * @param top the top of the line |
| 378 | * @param y the baseline |
| 379 | * @param bottom the bottom of the line |
| 380 | * @param needWidth true if the width value is required. |
| 381 | * @return the signed width of the run, based on the paragraph direction. |
| 382 | * Only valid if needWidth is true. |
| 383 | */ |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 384 | private float drawRun(Canvas c, int start, |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 385 | int limit, boolean runIsRtl, float x, int top, int y, int bottom, |
| 386 | boolean needWidth) { |
| 387 | |
| 388 | if ((mDir == Layout.DIR_LEFT_TO_RIGHT) == runIsRtl) { |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 389 | float w = -measureRun(start, limit, limit, runIsRtl, null); |
| 390 | handleRun(start, limit, limit, runIsRtl, c, x + w, top, |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 391 | y, bottom, null, false); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 392 | return w; |
| 393 | } |
| 394 | |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 395 | return handleRun(start, limit, limit, runIsRtl, c, x, top, |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 396 | y, bottom, null, needWidth); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 397 | } |
| 398 | |
| 399 | /** |
| 400 | * Measures a unidirectional (but possibly multi-styled) run of text. |
| 401 | * |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 402 | * |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 403 | * @param start the line-relative start of the run |
| 404 | * @param offset the offset to measure to, between start and limit inclusive |
| 405 | * @param limit the line-relative limit of the run |
| 406 | * @param runIsRtl true if the run is right-to-left |
| 407 | * @param fmi receives metrics information about the requested |
| 408 | * run, can be null. |
| 409 | * @return the signed width from the start of the run to the leading edge |
| 410 | * of the character at offset, based on the run (not paragraph) direction |
| 411 | */ |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 412 | private float measureRun(int start, int offset, int limit, boolean runIsRtl, |
| 413 | FontMetricsInt fmi) { |
| 414 | return handleRun(start, offset, limit, runIsRtl, null, 0, 0, 0, 0, fmi, true); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 415 | } |
| 416 | |
| 417 | /** |
| 418 | * Walk the cursor through this line, skipping conjuncts and |
| 419 | * zero-width characters. |
| 420 | * |
| 421 | * <p>This function cannot properly walk the cursor off the ends of the line |
| 422 | * since it does not know about any shaping on the previous/following line |
| 423 | * that might affect the cursor position. Callers must either avoid these |
| 424 | * situations or handle the result specially. |
| 425 | * |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 426 | * @param cursor the starting position of the cursor, between 0 and the |
| 427 | * length of the line, inclusive |
| 428 | * @param toLeft true if the caret is moving to the left. |
| 429 | * @return the new offset. If it is less than 0 or greater than the length |
| 430 | * of the line, the previous/following line should be examined to get the |
| 431 | * actual offset. |
| 432 | */ |
| 433 | int getOffsetToLeftRightOf(int cursor, boolean toLeft) { |
| 434 | // 1) The caret marks the leading edge of a character. The character |
| 435 | // logically before it might be on a different level, and the active caret |
| 436 | // position is on the character at the lower level. If that character |
| 437 | // was the previous character, the caret is on its trailing edge. |
| 438 | // 2) Take this character/edge and move it in the indicated direction. |
| 439 | // This gives you a new character and a new edge. |
| 440 | // 3) This position is between two visually adjacent characters. One of |
| 441 | // these might be at a lower level. The active position is on the |
| 442 | // character at the lower level. |
| 443 | // 4) If the active position is on the trailing edge of the character, |
| 444 | // the new caret position is the following logical character, else it |
| 445 | // is the character. |
| 446 | |
| 447 | int lineStart = 0; |
| 448 | int lineEnd = mLen; |
| 449 | boolean paraIsRtl = mDir == -1; |
| 450 | int[] runs = mDirections.mDirections; |
| 451 | |
| 452 | int runIndex, runLevel = 0, runStart = lineStart, runLimit = lineEnd, newCaret = -1; |
| 453 | boolean trailing = false; |
| 454 | |
| 455 | if (cursor == lineStart) { |
| 456 | runIndex = -2; |
| 457 | } else if (cursor == lineEnd) { |
| 458 | runIndex = runs.length; |
| 459 | } else { |
| 460 | // First, get information about the run containing the character with |
| 461 | // the active caret. |
| 462 | for (runIndex = 0; runIndex < runs.length; runIndex += 2) { |
| 463 | runStart = lineStart + runs[runIndex]; |
| 464 | if (cursor >= runStart) { |
| 465 | runLimit = runStart + (runs[runIndex+1] & Layout.RUN_LENGTH_MASK); |
| 466 | if (runLimit > lineEnd) { |
| 467 | runLimit = lineEnd; |
| 468 | } |
| 469 | if (cursor < runLimit) { |
| 470 | runLevel = (runs[runIndex+1] >>> Layout.RUN_LEVEL_SHIFT) & |
| 471 | Layout.RUN_LEVEL_MASK; |
| 472 | if (cursor == runStart) { |
| 473 | // The caret is on a run boundary, see if we should |
| 474 | // use the position on the trailing edge of the previous |
| 475 | // logical character instead. |
| 476 | int prevRunIndex, prevRunLevel, prevRunStart, prevRunLimit; |
| 477 | int pos = cursor - 1; |
| 478 | for (prevRunIndex = 0; prevRunIndex < runs.length; prevRunIndex += 2) { |
| 479 | prevRunStart = lineStart + runs[prevRunIndex]; |
| 480 | if (pos >= prevRunStart) { |
| 481 | prevRunLimit = prevRunStart + |
| 482 | (runs[prevRunIndex+1] & Layout.RUN_LENGTH_MASK); |
| 483 | if (prevRunLimit > lineEnd) { |
| 484 | prevRunLimit = lineEnd; |
| 485 | } |
| 486 | if (pos < prevRunLimit) { |
| 487 | prevRunLevel = (runs[prevRunIndex+1] >>> Layout.RUN_LEVEL_SHIFT) |
| 488 | & Layout.RUN_LEVEL_MASK; |
| 489 | if (prevRunLevel < runLevel) { |
| 490 | // Start from logically previous character. |
| 491 | runIndex = prevRunIndex; |
| 492 | runLevel = prevRunLevel; |
| 493 | runStart = prevRunStart; |
| 494 | runLimit = prevRunLimit; |
| 495 | trailing = true; |
| 496 | break; |
| 497 | } |
| 498 | } |
| 499 | } |
| 500 | } |
| 501 | } |
| 502 | break; |
| 503 | } |
| 504 | } |
| 505 | } |
| 506 | |
| 507 | // caret might be == lineEnd. This is generally a space or paragraph |
| 508 | // separator and has an associated run, but might be the end of |
| 509 | // text, in which case it doesn't. If that happens, we ran off the |
| 510 | // end of the run list, and runIndex == runs.length. In this case, |
| 511 | // we are at a run boundary so we skip the below test. |
| 512 | if (runIndex != runs.length) { |
| 513 | boolean runIsRtl = (runLevel & 0x1) != 0; |
| 514 | boolean advance = toLeft == runIsRtl; |
| 515 | if (cursor != (advance ? runLimit : runStart) || advance != trailing) { |
| 516 | // Moving within or into the run, so we can move logically. |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 517 | newCaret = getOffsetBeforeAfter(runIndex, runStart, runLimit, |
| 518 | runIsRtl, cursor, advance); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 519 | // If the new position is internal to the run, we're at the strong |
| 520 | // position already so we're finished. |
| 521 | if (newCaret != (advance ? runLimit : runStart)) { |
| 522 | return newCaret; |
| 523 | } |
| 524 | } |
| 525 | } |
| 526 | } |
| 527 | |
| 528 | // If newCaret is -1, we're starting at a run boundary and crossing |
| 529 | // into another run. Otherwise we've arrived at a run boundary, and |
| 530 | // need to figure out which character to attach to. Note we might |
| 531 | // need to run this twice, if we cross a run boundary and end up at |
| 532 | // another run boundary. |
| 533 | while (true) { |
| 534 | boolean advance = toLeft == paraIsRtl; |
| 535 | int otherRunIndex = runIndex + (advance ? 2 : -2); |
| 536 | if (otherRunIndex >= 0 && otherRunIndex < runs.length) { |
| 537 | int otherRunStart = lineStart + runs[otherRunIndex]; |
| 538 | int otherRunLimit = otherRunStart + |
| 539 | (runs[otherRunIndex+1] & Layout.RUN_LENGTH_MASK); |
| 540 | if (otherRunLimit > lineEnd) { |
| 541 | otherRunLimit = lineEnd; |
| 542 | } |
| 543 | int otherRunLevel = (runs[otherRunIndex+1] >>> Layout.RUN_LEVEL_SHIFT) & |
| 544 | Layout.RUN_LEVEL_MASK; |
| 545 | boolean otherRunIsRtl = (otherRunLevel & 1) != 0; |
| 546 | |
| 547 | advance = toLeft == otherRunIsRtl; |
| 548 | if (newCaret == -1) { |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 549 | newCaret = getOffsetBeforeAfter(otherRunIndex, otherRunStart, |
| 550 | otherRunLimit, otherRunIsRtl, |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 551 | advance ? otherRunStart : otherRunLimit, advance); |
| 552 | if (newCaret == (advance ? otherRunLimit : otherRunStart)) { |
| 553 | // Crossed and ended up at a new boundary, |
| 554 | // repeat a second and final time. |
| 555 | runIndex = otherRunIndex; |
| 556 | runLevel = otherRunLevel; |
| 557 | continue; |
| 558 | } |
| 559 | break; |
| 560 | } |
| 561 | |
| 562 | // The new caret is at a boundary. |
| 563 | if (otherRunLevel < runLevel) { |
| 564 | // The strong character is in the other run. |
| 565 | newCaret = advance ? otherRunStart : otherRunLimit; |
| 566 | } |
| 567 | break; |
| 568 | } |
| 569 | |
| 570 | if (newCaret == -1) { |
| 571 | // We're walking off the end of the line. The paragraph |
| 572 | // level is always equal to or lower than any internal level, so |
| 573 | // the boundaries get the strong caret. |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 574 | newCaret = advance ? mLen + 1 : -1; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 575 | break; |
| 576 | } |
| 577 | |
| 578 | // Else we've arrived at the end of the line. That's a strong position. |
| 579 | // We might have arrived here by crossing over a run with no internal |
| 580 | // breaks and dropping out of the above loop before advancing one final |
| 581 | // time, so reset the caret. |
| 582 | // Note, we use '<=' below to handle a situation where the only run |
| 583 | // on the line is a counter-directional run. If we're not advancing, |
| 584 | // we can end up at the 'lineEnd' position but the caret we want is at |
| 585 | // the lineStart. |
| 586 | if (newCaret <= lineEnd) { |
| 587 | newCaret = advance ? lineEnd : lineStart; |
| 588 | } |
| 589 | break; |
| 590 | } |
| 591 | |
| 592 | return newCaret; |
| 593 | } |
| 594 | |
| 595 | /** |
| 596 | * Returns the next valid offset within this directional run, skipping |
| 597 | * conjuncts and zero-width characters. This should not be called to walk |
Gilles Debunne | cc3ec6c | 2010-06-23 10:30:27 -0700 | [diff] [blame] | 598 | * off the end of the line, since the returned values might not be valid |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 599 | * on neighboring lines. If the returned offset is less than zero or |
| 600 | * greater than the line length, the offset should be recomputed on the |
| 601 | * preceding or following line, respectively. |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 602 | * |
| 603 | * @param runIndex the run index |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 604 | * @param runStart the start of the run |
| 605 | * @param runLimit the limit of the run |
| 606 | * @param runIsRtl true if the run is right-to-left |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 607 | * @param offset the offset |
| 608 | * @param after true if the new offset should logically follow the provided |
| 609 | * offset |
| 610 | * @return the new offset |
| 611 | */ |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 612 | private int getOffsetBeforeAfter(int runIndex, int runStart, int runLimit, |
| 613 | boolean runIsRtl, int offset, boolean after) { |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 614 | |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 615 | if (runIndex < 0 || offset == (after ? mLen : 0)) { |
| 616 | // Walking off end of line. Since we don't know |
| 617 | // what cursor positions are available on other lines, we can't |
| 618 | // return accurate values. These are a guess. |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 619 | if (after) { |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 620 | return TextUtils.getOffsetAfter(mText, offset + mStart) - mStart; |
| 621 | } |
| 622 | return TextUtils.getOffsetBefore(mText, offset + mStart) - mStart; |
| 623 | } |
| 624 | |
| 625 | TextPaint wp = mWorkPaint; |
| 626 | wp.set(mPaint); |
| 627 | |
| 628 | int spanStart = runStart; |
| 629 | int spanLimit; |
| 630 | if (mSpanned == null) { |
| 631 | spanLimit = runLimit; |
| 632 | } else { |
| 633 | int target = after ? offset + 1 : offset; |
| 634 | int limit = mStart + runLimit; |
| 635 | while (true) { |
| 636 | spanLimit = mSpanned.nextSpanTransition(mStart + spanStart, limit, |
| 637 | MetricAffectingSpan.class) - mStart; |
| 638 | if (spanLimit >= target) { |
| 639 | break; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 640 | } |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 641 | spanStart = spanLimit; |
| 642 | } |
| 643 | |
| 644 | MetricAffectingSpan[] spans = mSpanned.getSpans(mStart + spanStart, |
| 645 | mStart + spanLimit, MetricAffectingSpan.class); |
Gilles Debunne | 1e3ac18 | 2011-03-08 14:22:34 -0800 | [diff] [blame] | 646 | spans = TextUtils.removeEmptySpans(spans, mSpanned, MetricAffectingSpan.class); |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 647 | |
| 648 | if (spans.length > 0) { |
| 649 | ReplacementSpan replacement = null; |
| 650 | for (int j = 0; j < spans.length; j++) { |
| 651 | MetricAffectingSpan span = spans[j]; |
| 652 | if (span instanceof ReplacementSpan) { |
| 653 | replacement = (ReplacementSpan)span; |
| 654 | } else { |
| 655 | span.updateMeasureState(wp); |
| 656 | } |
| 657 | } |
| 658 | |
| 659 | if (replacement != null) { |
| 660 | // If we have a replacement span, we're moving either to |
| 661 | // the start or end of this span. |
| 662 | return after ? spanLimit : spanStart; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 663 | } |
| 664 | } |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 665 | } |
| 666 | |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 667 | int cursorOpt = after ? Paint.CURSOR_AFTER : Paint.CURSOR_BEFORE; |
| 668 | if (mCharsValid) { |
| 669 | return wp.getTextRunCursor(mChars, spanStart, spanLimit - spanStart, |
Fabrice Di Meglio | 6d9fe5b | 2013-02-11 18:27:34 -0800 | [diff] [blame^] | 670 | offset, cursorOpt); |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 671 | } else { |
| 672 | return wp.getTextRunCursor(mText, mStart + spanStart, |
Fabrice Di Meglio | 6d9fe5b | 2013-02-11 18:27:34 -0800 | [diff] [blame^] | 673 | mStart + spanLimit, mStart + offset, cursorOpt) - mStart; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 674 | } |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 675 | } |
| 676 | |
| 677 | /** |
Gilles Debunne | 0bb0009 | 2010-12-02 15:50:26 -0800 | [diff] [blame] | 678 | * @param wp |
| 679 | */ |
| 680 | private static void expandMetricsFromPaint(FontMetricsInt fmi, TextPaint wp) { |
| 681 | final int previousTop = fmi.top; |
| 682 | final int previousAscent = fmi.ascent; |
| 683 | final int previousDescent = fmi.descent; |
| 684 | final int previousBottom = fmi.bottom; |
| 685 | final int previousLeading = fmi.leading; |
| 686 | |
| 687 | wp.getFontMetricsInt(fmi); |
| 688 | |
Fabrice Di Meglio | 8a5137a | 2011-09-22 18:49:43 -0700 | [diff] [blame] | 689 | updateMetrics(fmi, previousTop, previousAscent, previousDescent, previousBottom, |
| 690 | previousLeading); |
| 691 | } |
| 692 | |
| 693 | static void updateMetrics(FontMetricsInt fmi, int previousTop, int previousAscent, |
| 694 | int previousDescent, int previousBottom, int previousLeading) { |
Gilles Debunne | 0bb0009 | 2010-12-02 15:50:26 -0800 | [diff] [blame] | 695 | fmi.top = Math.min(fmi.top, previousTop); |
| 696 | fmi.ascent = Math.min(fmi.ascent, previousAscent); |
| 697 | fmi.descent = Math.max(fmi.descent, previousDescent); |
| 698 | fmi.bottom = Math.max(fmi.bottom, previousBottom); |
| 699 | fmi.leading = Math.max(fmi.leading, previousLeading); |
| 700 | } |
| 701 | |
| 702 | /** |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 703 | * Utility function for measuring and rendering text. The text must |
| 704 | * not include a tab or emoji. |
| 705 | * |
| 706 | * @param wp the working paint |
| 707 | * @param start the start of the text |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 708 | * @param end the end of the text |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 709 | * @param runIsRtl true if the run is right-to-left |
| 710 | * @param c the canvas, can be null if rendering is not needed |
| 711 | * @param x the edge of the run closest to the leading margin |
| 712 | * @param top the top of the line |
| 713 | * @param y the baseline |
| 714 | * @param bottom the bottom of the line |
| 715 | * @param fmi receives metrics information, can be null |
| 716 | * @param needWidth true if the width of the run is needed |
| 717 | * @return the signed width of the run based on the run direction; only |
| 718 | * valid if needWidth is true |
| 719 | */ |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 720 | private float handleText(TextPaint wp, int start, int end, |
| 721 | int contextStart, int contextEnd, boolean runIsRtl, |
| 722 | Canvas c, float x, int top, int y, int bottom, |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 723 | FontMetricsInt fmi, boolean needWidth) { |
| 724 | |
Fabrice Di Meglio | 850dffa | 2011-08-08 09:45:09 -0700 | [diff] [blame] | 725 | // Get metrics first (even for empty strings or "0" width runs) |
| 726 | if (fmi != null) { |
| 727 | expandMetricsFromPaint(fmi, wp); |
| 728 | } |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 729 | |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 730 | int runLen = end - start; |
Fabrice Di Meglio | 850dffa | 2011-08-08 09:45:09 -0700 | [diff] [blame] | 731 | // No need to do anything if the run width is "0" |
| 732 | if (runLen == 0) { |
| 733 | return 0f; |
| 734 | } |
| 735 | |
| 736 | float ret = 0; |
| 737 | |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 738 | int contextLen = contextEnd - contextStart; |
Gilles Debunne | c9fd978 | 2011-09-09 09:20:12 -0700 | [diff] [blame] | 739 | if (needWidth || (c != null && (wp.bgColor != 0 || wp.underlineColor != 0 || runIsRtl))) { |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 740 | if (mCharsValid) { |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 741 | ret = wp.getTextRunAdvances(mChars, start, runLen, |
Fabrice Di Meglio | 6d9fe5b | 2013-02-11 18:27:34 -0800 | [diff] [blame^] | 742 | contextStart, contextLen, null, 0); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 743 | } else { |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 744 | int delta = mStart; |
Fabrice Di Meglio | 6d9fe5b | 2013-02-11 18:27:34 -0800 | [diff] [blame^] | 745 | ret = wp.getTextRunAdvances(mText, delta + start, delta + end, |
| 746 | delta + contextStart, delta + contextEnd, null, 0); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 747 | } |
| 748 | } |
| 749 | |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 750 | if (c != null) { |
| 751 | if (runIsRtl) { |
| 752 | x -= ret; |
| 753 | } |
| 754 | |
| 755 | if (wp.bgColor != 0) { |
Gilles Debunne | dd8f5ed | 2011-08-10 18:25:49 -0700 | [diff] [blame] | 756 | int previousColor = wp.getColor(); |
| 757 | Paint.Style previousStyle = wp.getStyle(); |
| 758 | |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 759 | wp.setColor(wp.bgColor); |
| 760 | wp.setStyle(Paint.Style.FILL); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 761 | c.drawRect(x, top, x + ret, bottom, wp); |
| 762 | |
Gilles Debunne | dd8f5ed | 2011-08-10 18:25:49 -0700 | [diff] [blame] | 763 | wp.setStyle(previousStyle); |
| 764 | wp.setColor(previousColor); |
| 765 | } |
| 766 | |
Gilles Debunne | c9fd978 | 2011-09-09 09:20:12 -0700 | [diff] [blame] | 767 | if (wp.underlineColor != 0) { |
Gilles Debunne | dd8f5ed | 2011-08-10 18:25:49 -0700 | [diff] [blame] | 768 | // kStdUnderline_Offset = 1/9, defined in SkTextFormatParams.h |
Luca Zanolin | e6d3682 | 2011-08-30 18:04:34 +0100 | [diff] [blame] | 769 | float underlineTop = y + wp.baselineShift + (1.0f / 9.0f) * wp.getTextSize(); |
Gilles Debunne | dd8f5ed | 2011-08-10 18:25:49 -0700 | [diff] [blame] | 770 | |
| 771 | int previousColor = wp.getColor(); |
| 772 | Paint.Style previousStyle = wp.getStyle(); |
Luca Zanolin | e6d3682 | 2011-08-30 18:04:34 +0100 | [diff] [blame] | 773 | boolean previousAntiAlias = wp.isAntiAlias(); |
Gilles Debunne | dd8f5ed | 2011-08-10 18:25:49 -0700 | [diff] [blame] | 774 | |
Gilles Debunne | dd8f5ed | 2011-08-10 18:25:49 -0700 | [diff] [blame] | 775 | wp.setStyle(Paint.Style.FILL); |
Luca Zanolin | e6d3682 | 2011-08-30 18:04:34 +0100 | [diff] [blame] | 776 | wp.setAntiAlias(true); |
| 777 | |
Gilles Debunne | c9fd978 | 2011-09-09 09:20:12 -0700 | [diff] [blame] | 778 | wp.setColor(wp.underlineColor); |
| 779 | c.drawRect(x, underlineTop, x + ret, underlineTop + wp.underlineThickness, wp); |
Gilles Debunne | dd8f5ed | 2011-08-10 18:25:49 -0700 | [diff] [blame] | 780 | |
| 781 | wp.setStyle(previousStyle); |
| 782 | wp.setColor(previousColor); |
Luca Zanolin | e6d3682 | 2011-08-30 18:04:34 +0100 | [diff] [blame] | 783 | wp.setAntiAlias(previousAntiAlias); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 784 | } |
| 785 | |
Fabrice Di Meglio | 6d9fe5b | 2013-02-11 18:27:34 -0800 | [diff] [blame^] | 786 | drawTextRun(c, wp, start, end, contextStart, contextEnd, x, y + wp.baselineShift); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 787 | } |
| 788 | |
| 789 | return runIsRtl ? -ret : ret; |
| 790 | } |
| 791 | |
| 792 | /** |
| 793 | * Utility function for measuring and rendering a replacement. |
| 794 | * |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 795 | * |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 796 | * @param replacement the replacement |
| 797 | * @param wp the work paint |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 798 | * @param start the start of the run |
| 799 | * @param limit the limit of the run |
| 800 | * @param runIsRtl true if the run is right-to-left |
| 801 | * @param c the canvas, can be null if not rendering |
| 802 | * @param x the edge of the replacement closest to the leading margin |
| 803 | * @param top the top of the line |
| 804 | * @param y the baseline |
| 805 | * @param bottom the bottom of the line |
| 806 | * @param fmi receives metrics information, can be null |
| 807 | * @param needWidth true if the width of the replacement is needed |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 808 | * @return the signed width of the run based on the run direction; only |
| 809 | * valid if needWidth is true |
| 810 | */ |
| 811 | private float handleReplacement(ReplacementSpan replacement, TextPaint wp, |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 812 | int start, int limit, boolean runIsRtl, Canvas c, |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 813 | float x, int top, int y, int bottom, FontMetricsInt fmi, |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 814 | boolean needWidth) { |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 815 | |
| 816 | float ret = 0; |
| 817 | |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 818 | int textStart = mStart + start; |
| 819 | int textLimit = mStart + limit; |
| 820 | |
| 821 | if (needWidth || (c != null && runIsRtl)) { |
Fabrice Di Meglio | 8a5137a | 2011-09-22 18:49:43 -0700 | [diff] [blame] | 822 | int previousTop = 0; |
| 823 | int previousAscent = 0; |
| 824 | int previousDescent = 0; |
| 825 | int previousBottom = 0; |
| 826 | int previousLeading = 0; |
| 827 | |
| 828 | boolean needUpdateMetrics = (fmi != null); |
| 829 | |
| 830 | if (needUpdateMetrics) { |
| 831 | previousTop = fmi.top; |
| 832 | previousAscent = fmi.ascent; |
| 833 | previousDescent = fmi.descent; |
| 834 | previousBottom = fmi.bottom; |
| 835 | previousLeading = fmi.leading; |
| 836 | } |
| 837 | |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 838 | ret = replacement.getSize(wp, mText, textStart, textLimit, fmi); |
Fabrice Di Meglio | 8a5137a | 2011-09-22 18:49:43 -0700 | [diff] [blame] | 839 | |
| 840 | if (needUpdateMetrics) { |
| 841 | updateMetrics(fmi, previousTop, previousAscent, previousDescent, previousBottom, |
| 842 | previousLeading); |
| 843 | } |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 844 | } |
| 845 | |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 846 | if (c != null) { |
| 847 | if (runIsRtl) { |
| 848 | x -= ret; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 849 | } |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 850 | replacement.draw(c, mText, textStart, textLimit, |
| 851 | x, top, y, bottom, wp); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 852 | } |
| 853 | |
| 854 | return runIsRtl ? -ret : ret; |
| 855 | } |
| 856 | |
| 857 | /** |
| 858 | * Utility function for handling a unidirectional run. The run must not |
| 859 | * contain tabs or emoji but can contain styles. |
| 860 | * |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 861 | * |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 862 | * @param start the line-relative start of the run |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 863 | * @param measureLimit the offset to measure to, between start and limit inclusive |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 864 | * @param limit the limit of the run |
| 865 | * @param runIsRtl true if the run is right-to-left |
| 866 | * @param c the canvas, can be null |
| 867 | * @param x the end of the run closest to the leading margin |
| 868 | * @param top the top of the line |
| 869 | * @param y the baseline |
| 870 | * @param bottom the bottom of the line |
| 871 | * @param fmi receives metrics information, can be null |
| 872 | * @param needWidth true if the width is required |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 873 | * @return the signed width of the run based on the run direction; only |
| 874 | * valid if needWidth is true |
| 875 | */ |
Romain Guy | bc7cdb6 | 2011-05-26 18:48:49 -0700 | [diff] [blame] | 876 | private float handleRun(int start, int measureLimit, |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 877 | int limit, boolean runIsRtl, Canvas c, float x, int top, int y, |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 878 | int bottom, FontMetricsInt fmi, boolean needWidth) { |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 879 | |
Gilles Debunne | f483e51 | 2011-04-28 15:08:54 -0700 | [diff] [blame] | 880 | // Case of an empty line, make sure we update fmi according to mPaint |
| 881 | if (start == measureLimit) { |
| 882 | TextPaint wp = mWorkPaint; |
| 883 | wp.set(mPaint); |
Fabrice Di Meglio | 15c097a | 2011-08-08 14:42:41 -0700 | [diff] [blame] | 884 | if (fmi != null) { |
| 885 | expandMetricsFromPaint(fmi, wp); |
| 886 | } |
| 887 | return 0f; |
Gilles Debunne | f483e51 | 2011-04-28 15:08:54 -0700 | [diff] [blame] | 888 | } |
| 889 | |
Gilles Debunne | 945ee9b | 2011-09-19 19:18:18 -0700 | [diff] [blame] | 890 | if (mSpanned == null) { |
| 891 | TextPaint wp = mWorkPaint; |
| 892 | wp.set(mPaint); |
| 893 | final int mlimit = measureLimit; |
| 894 | return handleText(wp, start, mlimit, start, limit, runIsRtl, c, x, top, |
| 895 | y, bottom, fmi, needWidth || mlimit < measureLimit); |
| 896 | } |
| 897 | |
Gilles Debunne | c1f4483 | 2011-12-08 16:03:00 -0800 | [diff] [blame] | 898 | mMetricAffectingSpanSpanSet.init(mSpanned, mStart + start, mStart + limit); |
| 899 | mCharacterStyleSpanSet.init(mSpanned, mStart + start, mStart + limit); |
Gilles Debunne | 945ee9b | 2011-09-19 19:18:18 -0700 | [diff] [blame] | 900 | |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 901 | // Shaping needs to take into account context up to metric boundaries, |
| 902 | // but rendering needs to take into account character style boundaries. |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 903 | // So we iterate through metric runs to get metric bounds, |
| 904 | // then within each metric run iterate through character style runs |
| 905 | // for the run bounds. |
Gilles Debunne | 945ee9b | 2011-09-19 19:18:18 -0700 | [diff] [blame] | 906 | final float originalX = x; |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 907 | for (int i = start, inext; i < measureLimit; i = inext) { |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 908 | TextPaint wp = mWorkPaint; |
| 909 | wp.set(mPaint); |
| 910 | |
Gilles Debunne | c1f4483 | 2011-12-08 16:03:00 -0800 | [diff] [blame] | 911 | inext = mMetricAffectingSpanSpanSet.getNextTransition(mStart + i, mStart + limit) - |
| 912 | mStart; |
Gilles Debunne | 945ee9b | 2011-09-19 19:18:18 -0700 | [diff] [blame] | 913 | int mlimit = Math.min(inext, measureLimit); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 914 | |
Gilles Debunne | 945ee9b | 2011-09-19 19:18:18 -0700 | [diff] [blame] | 915 | ReplacementSpan replacement = null; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 916 | |
Gilles Debunne | c1f4483 | 2011-12-08 16:03:00 -0800 | [diff] [blame] | 917 | for (int j = 0; j < mMetricAffectingSpanSpanSet.numberOfSpans; j++) { |
Gilles Debunne | 945ee9b | 2011-09-19 19:18:18 -0700 | [diff] [blame] | 918 | // Both intervals [spanStarts..spanEnds] and [mStart + i..mStart + mlimit] are NOT |
| 919 | // empty by construction. This special case in getSpans() explains the >= & <= tests |
Gilles Debunne | c1f4483 | 2011-12-08 16:03:00 -0800 | [diff] [blame] | 920 | if ((mMetricAffectingSpanSpanSet.spanStarts[j] >= mStart + mlimit) || |
| 921 | (mMetricAffectingSpanSpanSet.spanEnds[j] <= mStart + i)) continue; |
| 922 | MetricAffectingSpan span = mMetricAffectingSpanSpanSet.spans[j]; |
Gilles Debunne | 945ee9b | 2011-09-19 19:18:18 -0700 | [diff] [blame] | 923 | if (span instanceof ReplacementSpan) { |
| 924 | replacement = (ReplacementSpan)span; |
| 925 | } else { |
| 926 | // We might have a replacement that uses the draw |
| 927 | // state, otherwise measure state would suffice. |
| 928 | span.updateDrawState(wp); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 929 | } |
| 930 | } |
| 931 | |
Gilles Debunne | 945ee9b | 2011-09-19 19:18:18 -0700 | [diff] [blame] | 932 | if (replacement != null) { |
| 933 | x += handleReplacement(replacement, wp, i, mlimit, runIsRtl, c, x, top, y, |
| 934 | bottom, fmi, needWidth || mlimit < measureLimit); |
| 935 | continue; |
| 936 | } |
| 937 | |
Raph Levien | 42ef515d | 2012-10-22 15:01:17 -0700 | [diff] [blame] | 938 | for (int j = i, jnext; j < mlimit; j = jnext) { |
| 939 | jnext = mCharacterStyleSpanSet.getNextTransition(mStart + j, mStart + mlimit) - |
| 940 | mStart; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 941 | |
Raph Levien | 42ef515d | 2012-10-22 15:01:17 -0700 | [diff] [blame] | 942 | wp.set(mPaint); |
| 943 | for (int k = 0; k < mCharacterStyleSpanSet.numberOfSpans; k++) { |
| 944 | // Intentionally using >= and <= as explained above |
| 945 | if ((mCharacterStyleSpanSet.spanStarts[k] >= mStart + jnext) || |
| 946 | (mCharacterStyleSpanSet.spanEnds[k] <= mStart + j)) continue; |
Gilles Debunne | 945ee9b | 2011-09-19 19:18:18 -0700 | [diff] [blame] | 947 | |
Raph Levien | 42ef515d | 2012-10-22 15:01:17 -0700 | [diff] [blame] | 948 | CharacterStyle span = mCharacterStyleSpanSet.spans[k]; |
| 949 | span.updateDrawState(wp); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 950 | } |
Raph Levien | 42ef515d | 2012-10-22 15:01:17 -0700 | [diff] [blame] | 951 | |
| 952 | x += handleText(wp, j, jnext, i, inext, runIsRtl, c, x, |
| 953 | top, y, bottom, fmi, needWidth || jnext < measureLimit); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 954 | } |
| 955 | } |
| 956 | |
Gilles Debunne | 945ee9b | 2011-09-19 19:18:18 -0700 | [diff] [blame] | 957 | return x - originalX; |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 958 | } |
| 959 | |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 960 | /** |
| 961 | * Render a text run with the set-up paint. |
| 962 | * |
| 963 | * @param c the canvas |
| 964 | * @param wp the paint used to render the text |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 965 | * @param start the start of the run |
| 966 | * @param end the end of the run |
| 967 | * @param contextStart the start of context for the run |
| 968 | * @param contextEnd the end of the context for the run |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 969 | * @param x the x position of the left edge of the run |
| 970 | * @param y the baseline of the run |
| 971 | */ |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 972 | private void drawTextRun(Canvas c, TextPaint wp, int start, int end, |
Fabrice Di Meglio | 6d9fe5b | 2013-02-11 18:27:34 -0800 | [diff] [blame^] | 973 | int contextStart, int contextEnd, float x, int y) { |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 974 | |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 975 | if (mCharsValid) { |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 976 | int count = end - start; |
| 977 | int contextCount = contextEnd - contextStart; |
| 978 | c.drawTextRun(mChars, start, count, contextStart, contextCount, |
Fabrice Di Meglio | 6d9fe5b | 2013-02-11 18:27:34 -0800 | [diff] [blame^] | 979 | x, y, wp); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 980 | } else { |
Doug Felt | 0c702b8 | 2010-05-14 10:55:42 -0700 | [diff] [blame] | 981 | int delta = mStart; |
| 982 | c.drawTextRun(mText, delta + start, delta + end, |
Fabrice Di Meglio | 6d9fe5b | 2013-02-11 18:27:34 -0800 | [diff] [blame^] | 983 | delta + contextStart, delta + contextEnd, x, y, wp); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 984 | } |
| 985 | } |
| 986 | |
| 987 | /** |
| 988 | * Returns the ascent of the text at start. This is used for scaling |
| 989 | * emoji. |
| 990 | * |
| 991 | * @param pos the line-relative position |
| 992 | * @return the ascent of the text at start |
| 993 | */ |
| 994 | float ascent(int pos) { |
| 995 | if (mSpanned == null) { |
| 996 | return mPaint.ascent(); |
| 997 | } |
| 998 | |
| 999 | pos += mStart; |
Gilles Debunne | 945ee9b | 2011-09-19 19:18:18 -0700 | [diff] [blame] | 1000 | MetricAffectingSpan[] spans = mSpanned.getSpans(pos, pos + 1, MetricAffectingSpan.class); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 1001 | if (spans.length == 0) { |
| 1002 | return mPaint.ascent(); |
| 1003 | } |
| 1004 | |
| 1005 | TextPaint wp = mWorkPaint; |
| 1006 | wp.set(mPaint); |
| 1007 | for (MetricAffectingSpan span : spans) { |
| 1008 | span.updateMeasureState(wp); |
| 1009 | } |
| 1010 | return wp.ascent(); |
| 1011 | } |
| 1012 | |
| 1013 | /** |
| 1014 | * Returns the next tab position. |
| 1015 | * |
| 1016 | * @param h the (unsigned) offset from the leading margin |
| 1017 | * @return the (unsigned) tab position after this offset |
| 1018 | */ |
| 1019 | float nextTab(float h) { |
Doug Felt | c982f60 | 2010-05-25 11:51:40 -0700 | [diff] [blame] | 1020 | if (mTabs != null) { |
| 1021 | return mTabs.nextTab(h); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 1022 | } |
Doug Felt | c982f60 | 2010-05-25 11:51:40 -0700 | [diff] [blame] | 1023 | return TabStops.nextDefaultStop(h, TAB_INCREMENT); |
Doug Felt | e8e45f2 | 2010-03-29 14:58:40 -0700 | [diff] [blame] | 1024 | } |
| 1025 | |
| 1026 | private static final int TAB_INCREMENT = 20; |
| 1027 | } |