| /* |
| * Copyright (c) 1999, 2006, 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. |
| alloc.setRect(alloc.getX() + locs[0], alloc.getY(), 1, alloc.getHeight()); |
| return alloc; |
| } |
| |
| /** |
| * 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 pos 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. |
| * @exception BadLocationException |
| * @exception IllegalArgumentException for an invalid direction |
| */ |
| public int getNextVisualPositionFrom(GlyphView v, int pos, |
| Position.Bias b, Shape a, |
| int direction, |
| Position.Bias[] biasRet) |
| throws BadLocationException { |
| |
| int startOffset = v.getStartOffset(); |
| int endOffset = v.getEndOffset(); |
| Segment text; |
| AbstractDocument doc; |
| boolean viewIsLeftToRight; |
| TextHitInfo currentHit, nextHit; |
| |
| switch (direction) { |
| case View.NORTH: |
| break; |
| case View.SOUTH: |
| break; |
| case View.EAST: |
| doc = (AbstractDocument)v.getDocument(); |
| viewIsLeftToRight = doc.isLeftToRight(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: |
| doc = (AbstractDocument)v.getDocument(); |
| viewIsLeftToRight = doc.isLeftToRight(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; |
| |
| } |
