| /* | |
| * Copyright (c) 1999, 2017, Oracle and/or its affiliates. All rights reserved. | |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. | |
| * | |
| * This code is free software; you can redistribute it and/or modify it | |
| * under the terms of the GNU General Public License version 2 only, as | |
| * published by the Free Software Foundation. Oracle designates this | |
| * particular file as subject to the "Classpath" exception as provided | |
| * by Oracle in the LICENSE file that accompanied this code. | |
| * | |
| * This code is distributed in the hope that it will be useful, but WITHOUT | |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| * version 2 for more details (a copy is included in the LICENSE file that | |
| * accompanied this code). | |
| * | |
| * You should have received a copy of the GNU General Public License version | |
| * 2 along with this work; if not, write to the Free Software Foundation, | |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | |
| * | |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA | |
| * or visit www.oracle.com if you need additional information or have any | |
| * questions. | |
| */ | |
| package javax.swing.text; | |
| import java.text.*; | |
| import java.awt.*; | |
| import java.awt.font.*; | |
| import java.awt.geom.Rectangle2D; | |
| /** | |
| * A class to perform rendering of the glyphs. | |
| * This can be implemented to be stateless, or | |
| * to hold some information as a cache to | |
| * facilitate faster rendering and model/view | |
| * translation. At a minimum, the GlyphPainter | |
| * allows a View implementation to perform its | |
| * duties independent of a particular version | |
| * of JVM and selection of capabilities (i.e. | |
| * shaping for i18n, etc). | |
| * <p> | |
| * This implementation is intended for operation | |
| * under the JDK. It uses the | |
| * java.awt.font.TextLayout class to do i18n capable | |
| * rendering. | |
| * | |
| * @author Timothy Prinzing | |
| * @see GlyphView | |
| */ | |
| class GlyphPainter2 extends GlyphView.GlyphPainter { | |
| public GlyphPainter2(TextLayout layout) { | |
| this.layout = layout; | |
| } | |
| /** | |
| * Create a painter to use for the given GlyphView. | |
| */ | |
| public GlyphView.GlyphPainter getPainter(GlyphView v, int p0, int p1) { | |
| return null; | |
| } | |
| /** | |
| * Determine the span the glyphs given a start location | |
| * (for tab expansion). This implementation assumes it | |
| * has no tabs (i.e. TextLayout doesn't deal with tab | |
| * expansion). | |
| */ | |
| public float getSpan(GlyphView v, int p0, int p1, | |
| TabExpander e, float x) { | |
| if ((p0 == v.getStartOffset()) && (p1 == v.getEndOffset())) { | |
| return layout.getAdvance(); | |
| } | |
| int p = v.getStartOffset(); | |
| int index0 = p0 - p; | |
| int index1 = p1 - p; | |
| TextHitInfo hit0 = TextHitInfo.afterOffset(index0); | |
| TextHitInfo hit1 = TextHitInfo.beforeOffset(index1); | |
| float[] locs = layout.getCaretInfo(hit0); | |
| float x0 = locs[0]; | |
| locs = layout.getCaretInfo(hit1); | |
| float x1 = locs[0]; | |
| return (x1 > x0) ? x1 - x0 : x0 - x1; | |
| } | |
| public float getHeight(GlyphView v) { | |
| return layout.getAscent() + layout.getDescent() + layout.getLeading(); | |
| } | |
| /** | |
| * Fetch the ascent above the baseline for the glyphs | |
| * corresponding to the given range in the model. | |
| */ | |
| public float getAscent(GlyphView v) { | |
| return layout.getAscent(); | |
| } | |
| /** | |
| * Fetch the descent below the baseline for the glyphs | |
| * corresponding to the given range in the model. | |
| */ | |
| public float getDescent(GlyphView v) { | |
| return layout.getDescent(); | |
| } | |
| /** | |
| * Paint the glyphs for the given view. This is implemented | |
| * to only render if the Graphics is of type Graphics2D which | |
| * is required by TextLayout (and this should be the case if | |
| * running on the JDK). | |
| */ | |
| public void paint(GlyphView v, Graphics g, Shape a, int p0, int p1) { | |
| if (g instanceof Graphics2D) { | |
| Rectangle2D alloc = a.getBounds2D(); | |
| Graphics2D g2d = (Graphics2D)g; | |
| float y = (float) alloc.getY() + layout.getAscent() + layout.getLeading(); | |
| float x = (float) alloc.getX(); | |
| if( p0 > v.getStartOffset() || p1 < v.getEndOffset() ) { | |
| try { | |
| //TextLayout can't render only part of it's range, so if a | |
| //partial range is required, add a clip region. | |
| Shape s = v.modelToView(p0, Position.Bias.Forward, | |
| p1, Position.Bias.Backward, a); | |
| Shape savedClip = g.getClip(); | |
| g2d.clip(s); | |
| layout.draw(g2d, x, y); | |
| g.setClip(savedClip); | |
| } catch (BadLocationException e) {} | |
| } else { | |
| layout.draw(g2d, x, y); | |
| } | |
| } | |
| } | |
| public Shape modelToView(GlyphView v, int pos, Position.Bias bias, | |
| Shape a) throws BadLocationException { | |
| int offs = pos - v.getStartOffset(); | |
| Rectangle2D alloc = a.getBounds2D(); | |
| TextHitInfo hit = (bias == Position.Bias.Forward) ? | |
| TextHitInfo.afterOffset(offs) : TextHitInfo.beforeOffset(offs); | |
| float[] locs = layout.getCaretInfo(hit); | |
| // vertical at the baseline, should use slope and check if glyphs | |
| // are being rendered vertically. | |
| Rectangle2D rect = new Rectangle2D.Float(); | |
| rect.setRect(alloc.getX() + locs[0], alloc.getY(), 1, alloc.getHeight()); | |
| return rect; | |
| } | |
| /** | |
| * Provides a mapping from the view coordinate space to the logical | |
| * coordinate space of the model. | |
| * | |
| * @param v the view containing the view coordinates | |
| * @param x the X coordinate | |
| * @param y the Y coordinate | |
| * @param a the allocated region to render into | |
| * @param biasReturn either <code>Position.Bias.Forward</code> | |
| * or <code>Position.Bias.Backward</code> is returned as the | |
| * zero-th element of this array | |
| * @return the location within the model that best represents the | |
| * given point of view | |
| * @see View#viewToModel | |
| */ | |
| public int viewToModel(GlyphView v, float x, float y, Shape a, | |
| Position.Bias[] biasReturn) { | |
| Rectangle2D alloc = (a instanceof Rectangle2D) ? (Rectangle2D)a : a.getBounds2D(); | |
| //Move the y co-ord of the hit onto the baseline. This is because TextLayout supports | |
| //italic carets and we do not. | |
| TextHitInfo hit = layout.hitTestChar(x - (float)alloc.getX(), 0); | |
| int pos = hit.getInsertionIndex(); | |
| if (pos == v.getEndOffset()) { | |
| pos--; | |
| } | |
| biasReturn[0] = hit.isLeadingEdge() ? Position.Bias.Forward : Position.Bias.Backward; | |
| return pos + v.getStartOffset(); | |
| } | |
| /** | |
| * Determines the model location that represents the | |
| * maximum advance that fits within the given span. | |
| * This could be used to break the given view. The result | |
| * should be a location just shy of the given advance. This | |
| * differs from viewToModel which returns the closest | |
| * position which might be proud of the maximum advance. | |
| * | |
| * @param v the view to find the model location to break at. | |
| * @param p0 the location in the model where the | |
| * fragment should start it's representation >= 0. | |
| * @param x the graphic location along the axis that the | |
| * broken view would occupy >= 0. This may be useful for | |
| * things like tab calculations. | |
| * @param len specifies the distance into the view | |
| * where a potential break is desired >= 0. | |
| * @return the maximum model location possible for a break. | |
| * @see View#breakView | |
| */ | |
| public int getBoundedPosition(GlyphView v, int p0, float x, float len) { | |
| if( len < 0 ) | |
| throw new IllegalArgumentException("Length must be >= 0."); | |
| // note: this only works because swing uses TextLayouts that are | |
| // only pure rtl or pure ltr | |
| TextHitInfo hit; | |
| if (layout.isLeftToRight()) { | |
| hit = layout.hitTestChar(len, 0); | |
| } else { | |
| hit = layout.hitTestChar(layout.getAdvance() - len, 0); | |
| } | |
| return v.getStartOffset() + hit.getCharIndex(); | |
| } | |
| /** | |
| * Provides a way to determine the next visually represented model | |
| * location that one might place a caret. Some views may not be | |
| * visible, they might not be in the same order found in the model, or | |
| * they just might not allow access to some of the locations in the | |
| * model. | |
| * | |
| * @param v the view to use | |
| * @param pos the position to convert >= 0 | |
| * @param a the allocated region to render into | |
| * @param direction the direction from the current position that can | |
| * be thought of as the arrow keys typically found on a keyboard. | |
| * This may be SwingConstants.WEST, SwingConstants.EAST, | |
| * SwingConstants.NORTH, or SwingConstants.SOUTH. | |
| * @return the location within the model that best represents the next | |
| * location visual position. | |
| * @throws BadLocationException | |
| * @throws IllegalArgumentException for an invalid direction | |
| */ | |
| public int getNextVisualPositionFrom(GlyphView v, int pos, | |
| Position.Bias b, Shape a, | |
| int direction, | |
| Position.Bias[] biasRet) | |
| throws BadLocationException { | |
| Document doc = v.getDocument(); | |
| int startOffset = v.getStartOffset(); | |
| int endOffset = v.getEndOffset(); | |
| Segment text; | |
| boolean viewIsLeftToRight; | |
| TextHitInfo currentHit, nextHit; | |
| switch (direction) { | |
| case View.NORTH: | |
| break; | |
| case View.SOUTH: | |
| break; | |
| case View.EAST: | |
| viewIsLeftToRight = AbstractDocument.isLeftToRight(doc, startOffset, endOffset); | |
| if(startOffset == doc.getLength()) { | |
| if(pos == -1) { | |
| biasRet[0] = Position.Bias.Forward; | |
| return startOffset; | |
| } | |
| // End case for bidi text where newline is at beginning | |
| // of line. | |
| return -1; | |
| } | |
| if(pos == -1) { | |
| // Entering view from the left. | |
| if( viewIsLeftToRight ) { | |
| biasRet[0] = Position.Bias.Forward; | |
| return startOffset; | |
| } else { | |
| text = v.getText(endOffset - 1, endOffset); | |
| char c = text.array[text.offset]; | |
| SegmentCache.releaseSharedSegment(text); | |
| if(c == '\n') { | |
| biasRet[0] = Position.Bias.Forward; | |
| return endOffset-1; | |
| } | |
| biasRet[0] = Position.Bias.Backward; | |
| return endOffset; | |
| } | |
| } | |
| if( b==Position.Bias.Forward ) | |
| currentHit = TextHitInfo.afterOffset(pos-startOffset); | |
| else | |
| currentHit = TextHitInfo.beforeOffset(pos-startOffset); | |
| nextHit = layout.getNextRightHit(currentHit); | |
| if( nextHit == null ) { | |
| return -1; | |
| } | |
| if( viewIsLeftToRight != layout.isLeftToRight() ) { | |
| // If the layout's base direction is different from | |
| // this view's run direction, we need to use the weak | |
| // carrat. | |
| nextHit = layout.getVisualOtherHit(nextHit); | |
| } | |
| pos = nextHit.getInsertionIndex() + startOffset; | |
| if(pos == endOffset) { | |
| // A move to the right from an internal position will | |
| // only take us to the endOffset in a left to right run. | |
| text = v.getText(endOffset - 1, endOffset); | |
| char c = text.array[text.offset]; | |
| SegmentCache.releaseSharedSegment(text); | |
| if(c == '\n') { | |
| return -1; | |
| } | |
| biasRet[0] = Position.Bias.Backward; | |
| } | |
| else { | |
| biasRet[0] = Position.Bias.Forward; | |
| } | |
| return pos; | |
| case View.WEST: | |
| viewIsLeftToRight = AbstractDocument.isLeftToRight(doc, startOffset, endOffset); | |
| if(startOffset == doc.getLength()) { | |
| if(pos == -1) { | |
| biasRet[0] = Position.Bias.Forward; | |
| return startOffset; | |
| } | |
| // End case for bidi text where newline is at beginning | |
| // of line. | |
| return -1; | |
| } | |
| if(pos == -1) { | |
| // Entering view from the right | |
| if( viewIsLeftToRight ) { | |
| text = v.getText(endOffset - 1, endOffset); | |
| char c = text.array[text.offset]; | |
| SegmentCache.releaseSharedSegment(text); | |
| if ((c == '\n') || Character.isSpaceChar(c)) { | |
| biasRet[0] = Position.Bias.Forward; | |
| return endOffset - 1; | |
| } | |
| biasRet[0] = Position.Bias.Backward; | |
| return endOffset; | |
| } else { | |
| biasRet[0] = Position.Bias.Forward; | |
| return startOffset; | |
| } | |
| } | |
| if( b==Position.Bias.Forward ) | |
| currentHit = TextHitInfo.afterOffset(pos-startOffset); | |
| else | |
| currentHit = TextHitInfo.beforeOffset(pos-startOffset); | |
| nextHit = layout.getNextLeftHit(currentHit); | |
| if( nextHit == null ) { | |
| return -1; | |
| } | |
| if( viewIsLeftToRight != layout.isLeftToRight() ) { | |
| // If the layout's base direction is different from | |
| // this view's run direction, we need to use the weak | |
| // carrat. | |
| nextHit = layout.getVisualOtherHit(nextHit); | |
| } | |
| pos = nextHit.getInsertionIndex() + startOffset; | |
| if(pos == endOffset) { | |
| // A move to the left from an internal position will | |
| // only take us to the endOffset in a right to left run. | |
| text = v.getText(endOffset - 1, endOffset); | |
| char c = text.array[text.offset]; | |
| SegmentCache.releaseSharedSegment(text); | |
| if(c == '\n') { | |
| return -1; | |
| } | |
| biasRet[0] = Position.Bias.Backward; | |
| } | |
| else { | |
| biasRet[0] = Position.Bias.Forward; | |
| } | |
| return pos; | |
| default: | |
| throw new IllegalArgumentException("Bad direction: " + direction); | |
| } | |
| return pos; | |
| } | |
| // --- variables --------------------------------------------- | |
| TextLayout layout; | |
| } |