am 91f2a7cb: am 5a125053: Merge changes I66792c4d,I203b6783 into jb-mr2-dev

* commit '91f2a7cb303a3225f68f571ea101078eed1c1f94':
  Improve text rendering and measurement. [DO NOT MERGE]
  Fix the measurement of text bounds. [DO NOT MERGE]
This commit is contained in:
Deepanshu Gupta
2014-04-16 18:40:41 +00:00
committed by Android Git Automerger
3 changed files with 83 additions and 59 deletions

View File

@@ -20,6 +20,7 @@ import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.font.FontRenderContext;
import java.awt.font.GlyphVector;
import java.awt.geom.Rectangle2D;
import java.util.LinkedList;
import java.util.List;
@@ -50,9 +51,12 @@ public class BidiRenderer {
}
}
/* package */ Graphics2D graphics;
/* package */ Paint_Delegate paint;
/* package */ char[] text;
private Graphics2D mGraphics;
private Paint_Delegate mPaint;
private char[] mText;
// Bounds of the text drawn so far.
private RectF mBounds;
private float mBaseline;
/**
* @param graphics May be null.
@@ -61,9 +65,9 @@ public class BidiRenderer {
*/
/* package */ BidiRenderer(Graphics2D graphics, Paint_Delegate paint, char[] text) {
assert (paint != null);
this.graphics = graphics;
this.paint = paint;
this.text = text;
mGraphics = graphics;
mPaint = paint;
mText = text;
}
/**
@@ -77,61 +81,62 @@ public class BidiRenderer {
* @param advances If not null, then advances for each character to be rendered are returned
* here.
* @param advancesIndex index into advances from where the advances need to be filled.
* @param draw If true and {@link graphics} is not null, draw the rendered text on the graphics
* @param draw If true and {@code graphics} is not null, draw the rendered text on the graphics
* at the given co-ordinates
* @param x The x-coordinate of the left edge of where the text should be drawn on the given
* graphics.
* @param y The y-coordinate at which to draw the text on the given graphics.
* @return The x-coordinate of the right edge of the drawn text. In other words,
* x + the width of the text.
* @param y The y-coordinate at which to draw the text on the given mGraphics.
* @return A rectangle specifying the bounds of the text drawn.
*/
/* package */ float renderText(int start, int limit, boolean isRtl, float advances[],
/* package */ RectF renderText(int start, int limit, boolean isRtl, float[] advances,
int advancesIndex, boolean draw, float x, float y) {
// We break the text into scripts and then select font based on it and then render each of
// the script runs.
for (ScriptRun run : getScriptRuns(text, start, limit, isRtl, paint.getFonts())) {
mBounds = new RectF(x, y, x, y);
mBaseline = y;
for (ScriptRun run : getScriptRuns(mText, start, limit, isRtl, mPaint.getFonts())) {
int flag = Font.LAYOUT_NO_LIMIT_CONTEXT | Font.LAYOUT_NO_START_CONTEXT;
flag |= isRtl ? Font.LAYOUT_RIGHT_TO_LEFT : Font.LAYOUT_LEFT_TO_RIGHT;
x = renderScript(run.start, run.limit, run.font, flag, advances, advancesIndex, draw,
x, y);
renderScript(run.start, run.limit, run.font, flag, advances, advancesIndex, draw);
advancesIndex += run.limit - run.start;
}
return x;
return mBounds;
}
/**
* Render a script run. Use the preferred font to render as much as possible. This also
* implements a fallback mechanism to render characters that cannot be drawn using the
* preferred font.
*
* @return x + width of the text drawn.
* Render a script run to the right of the bounds passed. Use the preferred font to render as
* much as possible. This also implements a fallback mechanism to render characters that cannot
* be drawn using the preferred font.
*/
private float renderScript(int start, int limit, FontInfo preferredFont, int flag,
float advances[], int advancesIndex, boolean draw, float x, float y) {
List<FontInfo> fonts = paint.getFonts();
private void renderScript(int start, int limit, FontInfo preferredFont, int flag,
float[] advances, int advancesIndex, boolean draw) {
List<FontInfo> fonts = mPaint.getFonts();
if (fonts == null || preferredFont == null) {
return x;
return;
}
while (start < limit) {
boolean foundFont = false;
int canDisplayUpTo = preferredFont.mFont.canDisplayUpTo(text, start, limit);
int canDisplayUpTo = preferredFont.mFont.canDisplayUpTo(mText, start, limit);
if (canDisplayUpTo == -1) {
return render(start, limit, preferredFont, flag, advances, advancesIndex, draw,
x, y);
} else if (canDisplayUpTo > start) { // can draw something
x = render(start, canDisplayUpTo, preferredFont, flag, advances, advancesIndex,
draw, x, y);
// We can draw all characters in the text.
render(start, limit, preferredFont, flag, advances, advancesIndex, draw);
return;
}
if (canDisplayUpTo > start) {
// We can draw something.
render(start, canDisplayUpTo, preferredFont, flag, advances, advancesIndex, draw);
advancesIndex += canDisplayUpTo - start;
start = canDisplayUpTo;
}
int charCount = Character.isHighSurrogate(text[start]) ? 2 : 1;
// The current character cannot be drawn with the preferred font. Cycle through all the
// fonts to check which one can draw it.
int charCount = Character.isHighSurrogate(mText[start]) ? 2 : 1;
for (FontInfo font : fonts) {
canDisplayUpTo = font.mFont.canDisplayUpTo(text, start, start + charCount);
canDisplayUpTo = font.mFont.canDisplayUpTo(mText, start, start + charCount);
if (canDisplayUpTo == -1) {
x = render(start, start+charCount, font, flag, advances, advancesIndex, draw,
x, y);
render(start, start+charCount, font, flag, advances, advancesIndex, draw);
start += charCount;
advancesIndex += charCount;
foundFont = true;
@@ -143,46 +148,63 @@ public class BidiRenderer {
// probably appear as a box or a blank space. We could, probably, use some
// heuristics and break the character into the base character and diacritics and
// then draw it, but it's probably not worth the effort.
x = render(start, start + charCount, preferredFont, flag, advances, advancesIndex,
draw, x, y);
render(start, start + charCount, preferredFont, flag, advances, advancesIndex,
draw);
start += charCount;
advancesIndex += charCount;
}
}
return x;
}
/**
* Render the text with the given font.
* Renders the text to the right of the bounds with the given font.
* @param font The font to render the text with.
*/
private float render(int start, int limit, FontInfo font, int flag, float advances[],
int advancesIndex, boolean draw, float x, float y) {
private void render(int start, int limit, FontInfo font, int flag, float[] advances,
int advancesIndex, boolean draw) {
float totalAdvance = 0;
// Since the metrics don't have anti-aliasing set, we create a new FontRenderContext with
// the anti-aliasing set.
FontRenderContext f = font.mMetrics.getFontRenderContext();
FontRenderContext frc = new FontRenderContext(f.getTransform(), paint.isAntiAliased(),
FontRenderContext frc = new FontRenderContext(f.getTransform(), mPaint.isAntiAliased(),
f.usesFractionalMetrics());
GlyphVector gv = font.mFont.layoutGlyphVector(frc, text, start, limit, flag);
GlyphVector gv = font.mFont.layoutGlyphVector(frc, mText, start, limit, flag);
int ng = gv.getNumGlyphs();
int[] ci = gv.getGlyphCharIndices(0, ng, null);
for (int i = 0; i < ng; i++) {
float adv = gv.getGlyphMetrics(i).getAdvanceX();
if (advances != null) {
if (advances != null) {
for (int i = 0; i < ng; i++) {
int adv_idx = advancesIndex + ci[i];
advances[adv_idx] += adv;
advances[adv_idx] += gv.getGlyphMetrics(i).getAdvanceX();
}
totalAdvance += adv;
}
if (draw && graphics != null) {
graphics.drawGlyphVector(gv, x, y);
if (draw && mGraphics != null) {
mGraphics.drawGlyphVector(gv, mBounds.right, mBaseline);
}
// Update the bounds.
Rectangle2D awtBounds = gv.getLogicalBounds();
RectF bounds = awtRectToAndroidRect(awtBounds, mBounds.right, mBaseline);
// If the width of the bounds is zero, no text had been drawn earlier. Hence, use the
// coordinates from the bounds as an offset.
if (Math.abs(mBounds.right - mBounds.left) == 0) {
mBounds = bounds;
} else {
mBounds.union(bounds);
}
return x + totalAdvance;
}
// --- Static helper methods ---
private static RectF awtRectToAndroidRect(Rectangle2D awtRec, float offsetX, float offsetY) {
float left = (float) awtRec.getX();
float top = (float) awtRec.getY();
float right = (float) (left + awtRec.getWidth());
float bottom = (float) (top + awtRec.getHeight());
RectF androidRect = new RectF(left, top, right, bottom);
androidRect.offset(offsetX, offsetY);
return androidRect;
}
/* package */ static List<ScriptRun> getScriptRuns(char[] text, int start, int limit,
boolean isRtl, List<FontInfo> fonts) {
LinkedList<ScriptRun> scriptRuns = new LinkedList<ScriptRun>();

View File

@@ -990,7 +990,8 @@ public final class Canvas_Delegate {
int limit = index + count;
boolean isRtl = flags == Canvas.DIRECTION_RTL;
if (paintDelegate.getTextAlign() != Paint.Align.LEFT.nativeInt) {
float m = paintDelegate.measureText(text, index, count, isRtl);
RectF bounds = paintDelegate.measureText(text, index, count, isRtl);
float m = bounds.right - bounds.left;
if (paintDelegate.getTextAlign() == Paint.Align.CENTER.nativeInt) {
x -= m / 2;
} else if (paintDelegate.getTextAlign() == Paint.Align.RIGHT.nativeInt) {

View File

@@ -575,7 +575,8 @@ public class Paint_Delegate {
return 0;
}
return delegate.measureText(text, index, count, isRtl(bidiFlags));
RectF bounds = delegate.measureText(text, index, count, isRtl(bidiFlags));
return bounds.right - bounds.left;
}
@LayoutlibDelegate
@@ -614,7 +615,8 @@ public class Paint_Delegate {
}
// measure from start to end
float res = delegate.measureText(text, start, end - start + 1, isRtl(bidiFlags));
RectF bounds = delegate.measureText(text, start, end - start + 1, isRtl(bidiFlags));
float res = bounds.right - bounds.left;
if (measuredWidth != null) {
measuredWidth[measureIndex] = res;
@@ -991,8 +993,9 @@ public class Paint_Delegate {
boolean isRtl = isRtl(flags);
int limit = index + count;
return new BidiRenderer(null, delegate, text).renderText(
RectF bounds = new BidiRenderer(null, delegate, text).renderText(
index, limit, isRtl, advances, advancesIndex, false, 0, 0);
return bounds.right - bounds.left;
}
@LayoutlibDelegate
@@ -1058,9 +1061,7 @@ public class Paint_Delegate {
if (delegate == null || delegate.mFonts == null || delegate.mFonts.size() == 0) {
return;
}
int w = (int) delegate.measureText(text, index, count, isRtl(bidiFlags));
int h= delegate.getFonts().get(0).mMetrics.getHeight();
bounds.set(0, 0, w, h);
delegate.measureText(text, index, count, isRtl(bidiFlags)).roundOut(bounds);
}
@LayoutlibDelegate
@@ -1154,7 +1155,7 @@ public class Paint_Delegate {
}
}
/*package*/ float measureText(char[] text, int index, int count, boolean isRtl) {
/*package*/ RectF measureText(char[] text, int index, int count, boolean isRtl) {
return new BidiRenderer(null, this, text).renderText(
index, index + count, isRtl, null, 0, false, 0, 0);
}