textline.java

JAVA基本类源代码,大家可以学习学习!

            Object graphicOrFont = styledParagraph.getFontOrGraphicAt(pos);

            if (graphicOrFont instanceof GraphicAttribute) {
                
                GraphicAttribute graphicAttribute = (GraphicAttribute) graphicOrFont;
                do {
                    int chunkLimit = firstVisualChunk(charsLtoV, levels,
                                    pos, runLimit);

                    GraphicComponent nextGraphic =
                            new GraphicComponent(graphicAttribute, decorator, charsLtoV, levels, pos, chunkLimit);
                    pos = chunkLimit;

                    ++numComponents;
                    if (numComponents >= tempComponents.length) {
                        tempComponents = expandArray(tempComponents);
                    }

                    tempComponents[numComponents-1] = nextGraphic;

                } while(pos < runLimit);
            }
            else {
                Font font = (Font) graphicOrFont;

                tempComponents = createComponentsOnRun(pos, runLimit,
                                                        chars,
                                                        charsLtoV, levels,
                                                        factory, font, null,
                                                        frc,
                                                        decorator,
                                                        tempComponents,
                                                        numComponents);
                pos = runLimit;
                numComponents = tempComponents.length;
                while (tempComponents[numComponents-1] == null) {
                    numComponents -= 1;
                }
            }

        } while (pos < textLimit);

        TextLineComponent[] components;
        if (tempComponents.length == numComponents) {
            components = tempComponents;
        }
        else {
            components = new TextLineComponent[numComponents];
            System.arraycopy(tempComponents, 0, components, 0, numComponents);
        }

        return components;
    }

    /**
     * Create a TextLine from the Font and character data over the
     * range.  The range is relative to both the StyledParagraph and the
     * character array.
     */
    public static TextLine createLineFromText(char[] chars,
                                              StyledParagraph styledParagraph,
                                              TextLabelFactory factory,
                                              boolean isDirectionLTR,
                                              float[] baselineOffsets) {

        factory.setLineContext(0, chars.length);

        Bidi lineBidi = factory.getLineBidi();
        int[] charsLtoV = null;
        byte[] levels = null;

        if (lineBidi != null) {
            levels = BidiUtils.getLevels(lineBidi);
	    int[] charsVtoL = BidiUtils.createVisualToLogicalMap(levels);
            charsLtoV = BidiUtils.createInverseMap(charsVtoL);
        }

        TextLineComponent[] components =
            getComponents(styledParagraph, chars, 0, chars.length, charsLtoV, levels, factory);

        return new TextLine(components, baselineOffsets,
                            chars, 0, chars.length, charsLtoV, levels, isDirectionLTR);
    }

    /**
     * Compute the components order from the given components array and
     * logical-to-visual character mapping.  May return null if canonical.
     */
    private static int[] computeComponentOrder(TextLineComponent[] components,
                                               int[] charsLtoV) {

        /*
         * Create a visual ordering for the glyph sets.  The important thing
         * here is that the values have the proper rank with respect to
         * each other, not the exact values.  For example, the first glyph
         * set that appears visually should have the lowest value.  The last
         * should have the highest value.  The values are then normalized
         * to map 1-1 with positions in glyphs.
         *
         */
        int[] componentOrder = null;
        if (charsLtoV != null && components.length > 1) {
            componentOrder = new int[components.length];
            int gStart = 0;
            for (int i = 0; i < components.length; i++) {
                componentOrder[i] = charsLtoV[gStart];
                gStart += components[i].getNumCharacters();
            }

            componentOrder = BidiUtils.createContiguousOrder(componentOrder);
            componentOrder = BidiUtils.createInverseMap(componentOrder);
        }
        return componentOrder;
    }


    /**
     * Create a TextLine from the text.  chars is just the text in the iterator.
     */
    public static TextLine standardCreateTextLine(FontRenderContext frc,
                                                  AttributedCharacterIterator text,
                                                  char[] chars,
                                                  float[] baselineOffsets) {

        StyledParagraph styledParagraph = new StyledParagraph(text, chars);
        Bidi bidi = new Bidi(text);
	if (bidi.isLeftToRight()) {
	    bidi = null;
	}
        int layoutFlags = 0; // no extra info yet, bidi determines run and line direction
        TextLabelFactory factory = new TextLabelFactory(frc, chars, bidi, layoutFlags);

        boolean isDirectionLTR = true;
        if (bidi != null) {
            isDirectionLTR = bidi.baseIsLeftToRight();
        }
        return createLineFromText(chars, styledParagraph, factory, isDirectionLTR, baselineOffsets);
    }



    /*
     * A utility to get a range of text that is both logically and visually
     * contiguous.
     * If the entire range is ok, return limit, otherwise return the first
     * directional change after start.  We could do better than this, but
     * it doesn't seem worth it at the moment.
    private static int firstVisualChunk(int order[], byte direction[],
                                        int start, int limit)
    {
        if (order != null) {
            int min = order[start];
            int max = order[start];
            int count = limit - start;
            for (int i = start + 1; i < limit; i++) {
                min = Math.min(min, order[i]);
                max = Math.max(max, order[i]);
                if (max - min >= count) {
                    if (direction != null) {
                        byte baseLevel = direction[start];
                        for (int j = start + 1; j < i; j++) {
                            if (direction[j] != baseLevel) {
                                return j;
                            }
                        }
                    }
                    return i;
                }
            }
        }
        return limit;
    }
     */
    
    /**
     * When this returns, the ACI's current position will be at the start of the
     * first run which does NOT contain a GraphicAttribute.  If no such run exists
     * the ACI's position will be at the end, and this method will return false.
     */
    static boolean advanceToFirstFont(AttributedCharacterIterator aci) {
        
        for (char ch = aci.first(); ch != aci.DONE; ch = aci.setIndex(aci.getRunLimit())) {

            if (aci.getAttribute(TextAttribute.CHAR_REPLACEMENT) == null) {
                return true;
            }
        }
        
        return false;
    }
    
    static float[] getNormalizedOffsets(float[] baselineOffsets, byte baseline) {
        
        if (baselineOffsets[baseline] != 0) {
            float base = baselineOffsets[baseline];
            float[] temp = new float[baselineOffsets.length];
            for (int i = 0; i < temp.length; i++)
                temp[i] = baselineOffsets[i] - base;
            baselineOffsets = temp;
        }
        return baselineOffsets;
    }
    
    static Font getFontAtCurrentPos(AttributedCharacterIterator aci) {
        
        char ch = aci.current();
        Object value = aci.getAttribute(TextAttribute.FONT);
        if (value != null) {
            return (Font) value;
        }
        if (aci.getAttribute(TextAttribute.FAMILY) != null) {
            return Font.getFont(aci.getAttributes());
        }
        
        FontResolver resolver = FontResolver.getInstance();
        return resolver.getFont(resolver.getFontIndex(ch), aci.getAttributes());
    }
    
    /**
     * Utility method for getting justification ratio from attributes.
     */
    static float getJustifyRatio(Map attributes) {
        
        Object value = attributes.get(TextAttribute.JUSTIFICATION);
        
        if (value == null) {
            return 1;
        }
        
        float justifyRatio = ((Float)value).floatValue();
        if (justifyRatio < 0) {
            justifyRatio = 0;
        }
        else if (justifyRatio > 1) {
            justifyRatio = 1;
        }
        
        return justifyRatio;
    }

  /*
   * The new version requires that chunks be at the same level.
   */
    private static int firstVisualChunk(int order[], byte direction[],
                                        int start, int limit)
    {
        if (order != null && direction != null) {
          byte dir = direction[start];
          while (++start < limit && direction[start] == dir) {}
          return start;
        }
        return limit;
    }

  /*
   * create a new line with characters between charStart and charLimit
   * justified using the provided width and ratio.
   */
    public TextLine getJustifiedLine(float justificationWidth, float justifyRatio, int justStart, int justLimit) {

        TextLineComponent[] newComponents = new TextLineComponent[fComponents.length];
        System.arraycopy(fComponents, 0, newComponents, 0, fComponents.length);

        float leftHang = 0;
        float adv = 0;
        float justifyDelta = 0;
        boolean rejustify = false;
        do {
            adv = getAdvanceBetween(newComponents, 0, characterCount());

            // all characters outside the justification range must be in the base direction
            // of the layout, otherwise justification makes no sense.

            float justifyAdvance = getAdvanceBetween(newComponents, justStart, justLimit);

            // get the actual justification delta
            justifyDelta = (justificationWidth - justifyAdvance) * justifyRatio;

            // generate an array of GlyphJustificationInfo records to pass to
            // the justifier.  Array is visually ordered.

            // get positions that each component will be using
            int[] infoPositions = new int[newComponents.length];
            int infoCount = 0;
            for (int visIndex = 0; visIndex < newComponents.length; visIndex++) {
                int logIndex = fComponentVisualOrder == null ? visIndex : fComponentVisualOrder[visIndex];
                infoPositions[logIndex] = infoCount;
                infoCount += newComponents[logIndex].getNumJustificationInfos();
            }
            GlyphJustificationInfo[] infos = new GlyphJustificationInfo[infoCount];

            // get justification infos
            int compStart = 0;
            for (int i = 0; i < newComponents.length; i++) {
                TextLineComponent comp = newComponents[i];
                int compLength = comp.getNumCharacters();
                int compLimit = compStart + compLength;
                if (compLimit > justStart) {
                    int rangeMin = Math.max(0, justStart - compStart);
                    int rangeMax = Math.min(compLength, justLimit - compStart);
                    comp.getJustificationInfos(infos, infoPositions[i], rangeMin, rangeMax);

                    if (compLimit >= justLimit) {
                        break;
                    }
                }
            }

            // records are visually ordered, and contiguous, so start and end are
            // simply the places where we didn't fetch records
            int infoStart = 0;
            int infoLimit = infoCount;
            while (infoStart < infoLimit && infos[infoStart] == null) {
                ++infoStart;
            }

            while (infoLimit > infoStart && infos[infoLimit - 1] == null) {
                --infoLimit;
            }

            // invoke justifier on the records
            TextJustifier justifier = new TextJustifier(infos, infoStart, infoLimit);

            float[] deltas = justifier.justify(justifyDelta);

            boolean canRejustify = rejustify == false;
            boolean wantRejustify = false;
            boolean[] flags = new boolean[1];

            // apply justification deltas
            compStart = 0;
            for (int i = 0; i < newComponents.length; i++) {
                TextLineComponent comp = newComponents[i];
                int compLength = comp.getNumCharacters();
                int compLimit = compStart + compLength;
                if (compLimit > justStart) {
                    int rangeMin = Math.max(0, justStart - compStart);
                    int rangeMax = Math.min(compLength, justLimit - compStart);
                    newComponents[i] = comp.applyJustificationDeltas(deltas, infoPositions[i] * 2, flags);

                    wantRejustify |= flags[0];

                    if (compLimit >= justLimit) {
                        break;
                    }
                }
            }

            rejustify = wantRejustify && !rejustify; // only make two passes
        } while (rejustify);

        return new TextLine(newComponents, fBaselineOffsets, fChars, fCharsStart,
                            fCharsLimit, fCharLogicalOrder, fCharLevels,
                            fIsDirectionLTR);
    }

    // return the sum of the advances of text between the logical start and limit
    public static float getAdvanceBetween(TextLineComponent[] components, int start, int limit) {
        float advance = 0;

        int tlcStart = 0;
        for(int i = 0; i < components.length; i++) {
            TextLineComponent comp = components[i];

            int tlcLength = comp.getNumCharacters();
            int tlcLimit = tlcStart + tlcLength;
            if (tlcLimit > start) {
                int measureStart = Math.max(0, start - tlcStart);
                int measureLimit = Math.min(tlcLength, limit - tlcStart);
                advance += comp.getAdvanceBetween(measureStart, measureLimit);
                if (tlcLimit >= limit) {
                    break;
                }
            }

            tlcStart = tlcLimit;
        }

        return advance;
    }
}