/**
* Returns information about a position on the line.
*
* @param offset the line-relative character offset, between 0 and the line length, inclusive
* @param trailing true to measure the trailing edge of the character before offset, false to
* measure the leading edge of the character at offset.
* @param fmi receives metrics information about the requested character, can be null.
* @return the signed offset from the leading margin to the requested character edge.
*/
float measure(int offset, boolean trailing, FontMetricsInt fmi) {
int target = trailing ? offset - 1 : offset;
if (target < 0) {
return 0;
}
float h = 0;
if (!mHasTabs) {
if (mDirections == Layout.DIRS_ALL_LEFT_TO_RIGHT) {
return measureRun(0, offset, mLen, false, fmi);
}
if (mDirections == Layout.DIRS_ALL_RIGHT_TO_LEFT) {
return measureRun(0, offset, mLen, true, fmi);
}
}
char[] chars = mChars;
int[] runs = mDirections.mDirections;
for (int i = 0; i < runs.length; i += 2) {
int runStart = runs[i];
int runLimit = runStart + (runs[i + 1] & Layout.RUN_LENGTH_MASK);
if (runLimit > mLen) {
runLimit = mLen;
}
boolean runIsRtl = (runs[i + 1] & Layout.RUN_RTL_FLAG) != 0;
int segstart = runStart;
for (int j = mHasTabs ? runStart : runLimit; j <= runLimit; j++) {
int codept = 0;
Bitmap bm = null;
if (mHasTabs && j < runLimit) {
codept = chars[j];
if (codept >= 0xd800 && codept < 0xdc00 && j + 1 < runLimit) {
codept = Character.codePointAt(chars, j);
if (codept >= Layout.MIN_EMOJI && codept <= Layout.MAX_EMOJI) {
bm = Layout.EMOJI_FACTORY.getBitmapFromAndroidPua(codept);
} else if (codept > 0xffff) {
++j;
continue;
}
}
}
if (j == runLimit || codept == '\t' || bm != null) {
boolean inSegment = target >= segstart && target < j;
boolean advance = (mDir == Layout.DIR_RIGHT_TO_LEFT) == runIsRtl;
if (inSegment && advance) {
return h += measureRun(segstart, offset, j, runIsRtl, fmi);
}
float w = measureRun(segstart, j, j, runIsRtl, fmi);
h += advance ? w : -w;
if (inSegment) {
return h += measureRun(segstart, offset, j, runIsRtl, null);
}
if (codept == '\t') {
if (offset == j) {
return h;
}
h = mDir * nextTab(h * mDir);
if (target == j) {
return h;
}
}
if (bm != null) {
float bmAscent = ascent(j);
float wid = bm.getWidth() * -bmAscent / bm.getHeight();
h += mDir * wid;
j++;
}
segstart = j + 1;
}
}
}
return h;
}
/**
* Renders the TextLine.
*
* @param c the canvas to render on
* @param x the leading margin position
* @param top the top of the line
* @param y the baseline
* @param bottom the bottom of the line
*/
void draw(Canvas c, float x, int top, int y, int bottom) {
if (!mHasTabs) {
if (mDirections == Layout.DIRS_ALL_LEFT_TO_RIGHT) {
drawRun(c, 0, mLen, false, x, top, y, bottom, false);
return;
}
if (mDirections == Layout.DIRS_ALL_RIGHT_TO_LEFT) {
drawRun(c, 0, mLen, true, x, top, y, bottom, false);
return;
}
}
float h = 0;
int[] runs = mDirections.mDirections;
RectF emojiRect = null;
int lastRunIndex = runs.length - 2;
for (int i = 0; i < runs.length; i += 2) {
int runStart = runs[i];
int runLimit = runStart + (runs[i + 1] & Layout.RUN_LENGTH_MASK);
if (runLimit > mLen) {
runLimit = mLen;
}
boolean runIsRtl = (runs[i + 1] & Layout.RUN_RTL_FLAG) != 0;
int segstart = runStart;
for (int j = mHasTabs ? runStart : runLimit; j <= runLimit; j++) {
int codept = 0;
Bitmap bm = null;
if (mHasTabs && j < runLimit) {
codept = mChars[j];
if (codept >= 0xd800 && codept < 0xdc00 && j + 1 < runLimit) {
codept = Character.codePointAt(mChars, j);
if (codept >= Layout.MIN_EMOJI && codept <= Layout.MAX_EMOJI) {
bm = Layout.EMOJI_FACTORY.getBitmapFromAndroidPua(codept);
} else if (codept > 0xffff) {
++j;
continue;
}
}
}
if (j == runLimit || codept == '\t' || bm != null) {
h +=
drawRun(
c, segstart, j, runIsRtl, x + h, top, y, bottom, i != lastRunIndex || j != mLen);
if (codept == '\t') {
h = mDir * nextTab(h * mDir);
} else if (bm != null) {
float bmAscent = ascent(j);
float bitmapHeight = bm.getHeight();
float scale = -bmAscent / bitmapHeight;
float width = bm.getWidth() * scale;
if (emojiRect == null) {
emojiRect = new RectF();
}
emojiRect.set(x + h, y + bmAscent, x + h + width, y);
c.drawBitmap(bm, null, emojiRect, mPaint);
h += width;
j++;
}
segstart = j + 1;
}
}
}
}
