Reorganize MeasuredText API

This CL changes the MeasuredText API:
- Rename MeasuredText to PrecomputedText.
- PrecomputedText is no longer a Spanned.
- Introduce PrecomputedText.Param which holds all text layout parameters.
- Add API to get PrecomputedText.Param from TextView.
- Remove MeasuredText.Builder and add PrecomputedText.create method instead.
- Remove setRange from MeasuredText since it is not for normal use case.
  (It can not be used for TextView)

Here is a performance scores: (median, walleye-userdebug, N=20)

StaticLayout creation time (w/o patch -> w/ patch)
 PrecomputedText Balanced Hyphenation  :    743,615 ->    737,145: (-0.9%)
 PrecomputedText Balanced NoHyphenation:    551,544 ->    542,715: (-1.6%)
 PrecomputedText Greedy Hyphenation    :    500,343 ->    499,601: (-0.1%)
 PrecomputedText Greedy NoHyphenation  :    497,987 ->    492,587: (-1.1%)
 RandomText Balanced Hyphenation       : 19,100,592 -> 19,135,289: (+0.2%)
 RandomText Balanced NoHyphenation     :  8,015,088 ->  7,954,260: (-0.8%)
 RandomText Greedy Hyphenation         :  7,950,915 ->  7,877,424: (-0.9%)
 RandomText Greedy NoHyphenation       :  7,939,337 ->  7,863,471: (-1.0%)

PrecomputedText creation time (w/o patch -> w/ patch)
 NoStyled Hyphenation                  : 18,935,638 -> 18,925,422: (-0.1%)
 NoStyled Hyphenation WidthOnly        : 18,469,726 -> 18,978,413: (+2.8%)
 NoStyled NoHyphenation                :  7,940,792 ->  7,919,127: (-0.3%)
 NoStyled NoHyphenation WidthOnly      :  7,463,230 ->  7,922,643: (+6.2%)
 Styled Hyphenation                    : 14,822,501 -> 14,809,017: (-0.1%)
 Styled Hyphenation WidthOnly          : 13,891,770 -> 14,656,617: (+5.5%)
 Styled NoHyphenation                  : 14,511,134 -> 14,301,503: (-1.4%)
 Styled NoHyphenation WidthOnly        : 13,495,345 -> 14,264,314: (+5.7%)

StaticLayout draw time (w/o patch -> w/ patch)
 PrecomputedText NoStyled              :    663,974 ->    661,610: (-0.4%)
 PrecomputedText NoStyled WithoutCache :    648,294 ->    648,766: (+0.1%)
 PrecomputedText Styled                :    879,322 ->    852,770: (-3.0%)
 PrecomputedText Styled WithoutCache   :  1,084,570 ->  1,110,147: (+2.4%)
 RandomText NoStyled                   :    565,682 ->    555,435: (-1.8%)
 RandomText NoStyled WithoutCache      :  9,070,533 ->  9,064,825: (-0.1%)
 RandomText Styled                     :  2,955,202 ->  2,962,008: (+0.2%)
 RandomText Styled WithoutCache        : 12,242,325 -> 12,228,573: (-0.1%)

Bug: 67504091
Bug: 73091756
Test: bit FrameworksCoreTests:android.text.
Test: atest CtsWidgetTestCases:EditTextTest \
    CtsWidgetTestCases:TextViewFadingEdgeTest \
    FrameworksCoreTests:TextViewFallbackLineSpacingTest \
    FrameworksCoreTests:TextViewTest FrameworksCoreTests:TypefaceTest \
    CtsGraphicsTestCases:TypefaceTest CtsWidgetTestCases:TextViewTest \
    CtsTextTestCases
Change-Id: I7db9e2ca4db68a16648cfb8fcf63555f501304c2

1 files changed, 28 insertions, 14 deletions

diff --git a/core/java/android/text/TextLine.java b/core/java/android/text/TextLine.java
index 55367dcce47e..be5bb4d1809a 100644
--- a/core/java/android/text/TextLine.java
+++ b/core/java/android/text/TextLine.java
@@ -16,6 +16,7 @@
 
 package android.text;
 
+import android.annotation.IntRange;
 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.graphics.Canvas;
@@ -60,7 +61,7 @@ public class TextLine {
     private char[] mChars;
     private boolean mCharsValid;
     private Spanned mSpanned;
-    private MeasuredText mMeasured;
+    private PrecomputedText mComputed;
 
     // Additional width of whitespace for justification. This value is per whitespace, thus
     // the line width will increase by mAddedWidth x (number of stretchable whitespaces).
@@ -119,7 +120,7 @@ public class TextLine {
         tl.mSpanned = null;
         tl.mTabs = null;
         tl.mChars = null;
-        tl.mMeasured = null;
+        tl.mComputed = null;
 
         tl.mMetricAffectingSpanSpanSet.recycle();
         tl.mCharacterStyleSpanSet.recycle();
@@ -149,10 +150,31 @@ public class TextLine {
      * @param tabStops the tabStops. Can be null.
      */
     @VisibleForTesting(visibility = VisibleForTesting.Visibility.PACKAGE)
-    public void set(TextPaint paint, CharSequence text, int start, int limit, int dir,
-            Directions directions, boolean hasTabs, TabStops tabStops) {
+    public void set(TextPaint paint, CharSequence text, int start,
+            int limit, int dir, Directions directions, boolean hasTabs, TabStops tabStops) {
+        set(paint, text, null, start, limit, dir, directions, hasTabs, tabStops);
+    }
+
+    /**
+     * Initializes a TextLine and prepares it for use.
+     *
+     * @param paint the base paint for the line
+     * @param text the text, can be Styled
+     * @param precomputed the precomputed text
+     * @param start the start of the line relative to the text
+     * @param limit the limit of the line relative to the text
+     * @param dir the paragraph direction of this line
+     * @param directions the directions information of this line
+     * @param hasTabs true if the line might contain tabs
+     * @param tabStops the tabStops.
+     */
+    public void set(@NonNull TextPaint paint, @NonNull CharSequence text,
+            @Nullable PrecomputedText precomputed, @IntRange(from = 0) int start,
+            @IntRange(from = 0) int limit, int dir, @NonNull Directions directions, boolean hasTabs,
+            @Nullable TabStops tabStops) {
         mPaint = paint;
         mText = text;
+        mComputed = precomputed;
         mStart = start;
         mLen = limit - start;
         mDir = dir;
@@ -170,14 +192,6 @@ public class TextLine {
             hasReplacement = mReplacementSpanSpanSet.numberOfSpans > 0;
         }
 
-        mMeasured = null;
-        if (text instanceof MeasuredText) {
-            MeasuredText mt = (MeasuredText) text;
-            if (mt.canUseMeasuredResult(paint)) {
-                mMeasured = mt;
-            }
-        }
-
         mCharsValid = hasReplacement || hasTabs || directions != Layout.DIRS_ALL_LEFT_TO_RIGHT;
 
         if (mCharsValid) {
@@ -746,12 +760,12 @@ public class TextLine {
             return wp.getRunAdvance(mChars, start, end, contextStart, contextEnd, runIsRtl, offset);
         } else {
             final int delta = mStart;
-            if (mMeasured == null) {
+            if (mComputed == null) {
                 // TODO: Enable measured getRunAdvance for ReplacementSpan and RTL text.
                 return wp.getRunAdvance(mText, delta + start, delta + end,
                         delta + contextStart, delta + contextEnd, runIsRtl, delta + offset);
             } else {
-                return mMeasured.getWidth(start + delta, end + delta);
+                return mComputed.getWidth(start + delta, end + delta);
             }
         }
     }