diff options
Diffstat (limited to 'dw/textblock.hh')
| -rw-r--r-- | dw/textblock.hh | 244 |
1 files changed, 212 insertions, 32 deletions
diff --git a/dw/textblock.hh b/dw/textblock.hh index ea7795b8..8d8f91cc 100644 --- a/dw/textblock.hh +++ b/dw/textblock.hh @@ -1,18 +1,29 @@ #ifndef __DW_TEXTBLOCK_HH__ #define __DW_TEXTBLOCK_HH__ +#include <limits.h> + #include "core.hh" #include "../lout/misc.hh" +// These were used when improved line breaking and hyphenation were +// implemented. Should be cleaned up; perhaps reactivate RTFL again. +#define PRINTF(fmt, ...) +#define PUTCHAR(ch) + namespace dw { /** * \brief A Widget for rendering text blocks, i.e. paragraphs or sequences * of paragraphs. * - * <strong>Important Note:</strong>: This documentation is out of date, since - * floats have been implementet. Will be updated and extended soon. - * + * <div style="border: 2px solid #ffff00; margin-top: 0.5em; + * margin-bottom: 0.5em; padding: 0.5em 1em; background-color: + * #ffffe0"><b>Info:</b> The recent changes (line breaking and + * hyphenation on one hand, floats on the other hand) have not yet + * been incorporated into this documentation. See \ref + * dw-line-breaking and \ref dw-special-textflow.</div> + * * <h3>Signals</h3> * * dw::Textblock uses the signals defined in @@ -134,6 +145,76 @@ namespace dw { class Textblock: public core::Widget { private: + // Hint: the following is somewhat chaotic, as a result of the merge + // of dillo_hyphen and dillo_floats + + // Part 1 -- Line-Breaking and Hyphenation + + /** + * This class encapsulates the badness/penalty calculation, and so + * (i) makes changes (hopefully) simpler, and (ii) hides the + * integer arithmetics (floating point arithmetics avoided for + * performance reasons). Unfortunately, the value range of the + * badness is not well defined, so fiddling with the penalties is a + * bit difficult. + */ + class BadnessAndPenalty + { + private: + enum { NOT_STRETCHABLE, QUITE_LOOSE, BADNESS_VALUE, TOO_TIGHT } + badnessState; + enum { FORCE_BREAK, PROHIBIT_BREAK, PENALTY_VALUE } penaltyState; + int ratio; // ratio is only defined when badness is defined + int badness, penalty; + + // for debugging: + int totalWidth, idealWidth, totalStretchability, totalShrinkability; + + // "Infinity levels" are used to represent very large numbers, + // including "quasi-infinite" numbers. A couple of infinity + // level and number can be mathematically represented as + // + // number * N ^ (infinity level) + // + // where N is a number which is large enough. Practically, + // infinity levels are used to circumvent limited ranges for + // integer numbers. + + // Here, all infinity levels have got special meanings. + enum { + INF_VALUE = 0, /* simple values */ + INF_LARGE, /* large values, like QUITE_LOOSE */ + INF_NOT_STRETCHABLE, /* reserved for NOT_STRECTHABLE */ + INF_PENALTIES, /* used for penalties */ + INF_TOO_TIGHT, /* used for lines, which are too tight; + that this is the last value means + that lines, which are too tight, are + regarded as the worst case */ + INF_MAX = INF_TOO_TIGHT + }; + + int badnessValue (int infLevel); + int penaltyValue (int infLevel); + + public: + void calcBadness (int totalWidth, int idealWidth, + int totalStretchability, int totalShrinkability); + void setPenalty (int penalty); + void setPenaltyProhibitBreak (); + void setPenaltyForceBreak (); + + bool lineLoose (); + bool lineTight (); + bool lineTooTight (); + bool lineMustBeBroken (); + bool lineCanBeBroken (); + int compareTo (BadnessAndPenalty *other); + + void print (); + }; + + // Part 2 -- Floats + Textblock *containingBox; class FloatSide @@ -192,8 +273,19 @@ private: }; FloatSide *leftFloatSide, *rightFloatSide; - + + // End of merge chaos. + protected: + enum { + /** + * The penalty for hyphens, multiplied with 100. So, 100 means + * 1.0. See dw::Textblock::BadnessAndPenalty::setPenalty for + * more details. + */ + HYPHEN_BREAK = 100 + }; + struct Line { int firstWord; /* first word's index in word vector */ @@ -209,17 +301,35 @@ protected: * widgets within this line. */ int marginDescent; - /* The following members contain accumulated values, from the top - * down to the line before. */ - int maxLineWidth; /* maximum of all line widths */ - int maxWordMin; /* maximum of all word minima */ - int maxParMax; /* maximum of all paragraph maxima */ - int parMin; /* the minimal total width down from the last - * paragraph start, to the *beginning* of the - * line */ - int parMax; /* the maximal total width down from the last - * paragraph start, to the *beginning* of the - * line */ + /* The following members contain accumulated values, from the + * top down to this line. Please notice a change: until + * recently, the values were accumulated up to the last line, + * not this line. + * + * Also, keep in mind that at the end of a line, the space of + * the last word is ignored, but instead, the hyphen width must + * be considered.*/ + + int maxLineWidth; /* Maximum of all line widths, including this + * line. Does not include the last space, but + * the last hyphen width. */ + int maxParMin; /* Maximum of all paragraph minima, including + * this line. */ + int maxParMax; /* Maximum of all paragraph maxima. This line + * is only included, if it is the last line of + * the paragraph (last word is a forced + * break); otherwise, it is the value of the + * last paragraph. For this reason, consider + * also parMax. */ + int parMax; /* The maximal total width down from the last + * paragraph start, to the *end* of this line. + * The space at the end of this line is + * included, but not the hyphen width (as + * opposed to the other values). So, in some + * cases, the space has to be subtracted and + * the hyphen width to be added, to compare it + * to maxParMax. (Search the code for + * occurances.) */ }; struct Word @@ -228,15 +338,39 @@ protected: core::Requisition size; /* Space after the word, only if it's not a break: */ short origSpace; /* from font, set by addSpace */ + short stretchability, shrinkability; short effSpace; /* effective space, set by wordWrap, * used for drawing etc. */ + short hyphenWidth; /* Additional width, when a word is part + * (except the last part) of a hyphenationed + * word. Has to be added to the width, when + * this is the last word of the line, and + * "hyphenWidth > 0" is also used to decide + * weather to draw a hyphen. */ core::Content content; + bool canBeHyphenated; + + // accumulated values, relative to the beginning of the line + int totalWidth; /* The sum of all word widths; plus all + spaces, excluding the one of this + word; plus the hypthen width of this + word (but of course, no hyphen + widths of previous words. In other + words: the value compared to the + ideal width of the line, if the line + would be broken after this word. */ + int totalStretchability; // includes all *before* current word + int totalShrinkability; // includes all *before* current word + BadnessAndPenalty badnessAndPenalty; /* when line is broken after this + * word */ core::style::Style *style; core::style::Style *spaceStyle; /* initially the same as of the word, later set by a_Dw_page_add_space */ }; + void printWord (Word *word); + struct Anchor { char *name; @@ -303,13 +437,11 @@ protected: /* These values are set by set_... */ int availWidth, availAscent, availDescent; - int lastLineWidth; - int lastLineParMin; - int lastLineParMax; int wrapRef; /* [0 based] */ lout::misc::SimpleVector <Line> *lines; - lout::misc::SimpleVector <Word> *words; + int nonTemporaryLines; + lout::misc::NotSoSimpleVector <Word> *words; lout::misc::SimpleVector <Anchor> *anchors; struct {int index, nChar;} @@ -321,23 +453,38 @@ protected: void queueDrawRange (int index1, int index2); void getWordExtremes (Word *word, core::Extremes *extremes); void markChange (int ref); - void justifyLine (Line *line, int availWidth); - Line *addLine (int wordInd, bool newPar); + void justifyLine (Line *line, int diff); + Line *addLine (int firstWord, int lastWord, bool temporary); void calcWidgetSize (core::Widget *widget, core::Requisition *size); void rewrap (); - void decorateText(core::View *view, core::style::Style *style, - core::style::Color::Shading shading, - int x, int yBase, int width); - void drawText(int wordIndex, core::View *view, core::Rectangle *area, - int xWidget, int yWidgetBase); - void drawSpace(int wordIndex, core::View *view, core::Rectangle *area, - int xWidget, int yWidgetBase); + void showMissingLines (); + void removeTemporaryLines (); + + void decorateText (core::View *view, core::style::Style *style, + core::style::Color::Shading shading, + int x, int yBase, int width); + void drawText (core::View *view, core::style::Style *style, + core::style::Color::Shading shading, int x, int y, + const char *text, int start, int len); + void drawWord (Line *line, int wordIndex1, int wordIndex2, core::View *view, + core::Rectangle *area, int xWidget, int yWidgetBase); + void drawWord0 (int wordIndex1, int wordIndex2, + const char *text, int totalWidth, + core::style::Style *style, core::View *view, + core::Rectangle *area, int xWidget, int yWidgetBase); + void drawSpace (int wordIndex, core::View *view, core::Rectangle *area, + int xWidget, int yWidgetBase); void drawLine (Line *line, core::View *view, core::Rectangle *area); int findLineIndex (int y); int findLineOfWord (int wordIndex); Word *findWord (int x, int y, bool *inSpace); - Word *addWord (int width, int ascent, int descent, + Word *addWord (int width, int ascent, int descent, bool canBeHyphenated, + core::style::Style *style); + void fillWord (Word *word, int width, int ascent, int descent, + bool canBeHyphenated, core::style::Style *style); + void fillSpace (Word *word, core::style::Style *style); + int textWidth (const char *text, int start, int len, core::style::Style *style); void calcTextSize (const char *text, size_t len, core::style::Style *style, core::Requisition *size); @@ -361,7 +508,7 @@ protected: inline int lineXOffsetContents (Line *line) { return innerPadding + line->leftOffset + line->boxLeft + - (line == lines->getRef (0) ? line1OffsetEff : 0); + (line == lines->getFirstRef() ? line1OffsetEff : 0); } /** @@ -414,7 +561,15 @@ protected: bool sendSelectionEvent (core::SelectionState::EventType eventType, core::MousePositionEvent *event); - virtual void wordWrap(int wordIndex); + void accumulateWordExtremes (int firstWord, int lastWord, + int *maxOfMinWidth, int *sumOfMaxWidth); + virtual void wordWrap (int wordIndex, bool wrapAll); + int hyphenateWord (int wordIndex); + void accumulateWordForLine (int lineIndex, int wordIndex); + void accumulateWordData(int wordIndex); + int calcAvailWidth (int lineIndex); + void initLine1Offset (int wordIndex); + void alignLine (int lineIndex); void sizeRequestImpl (core::Requisition *requisition); void getExtremesImpl (core::Extremes *extremes); @@ -438,6 +593,13 @@ protected: void removeChild (Widget *child); + void addText0 (const char *text, size_t len, bool canBeHyphenated, + core::style::Style *style, core::Requisition *size); + void calcTextSizes (const char *text, size_t textLen, + core::style::Style *style, + int numBreaks, int *breakPos, + core::Requisition *wordSize); + public: static int CLASS_ID; @@ -455,7 +617,25 @@ public: } void addWidget (core::Widget *widget, core::style::Style *style); bool addAnchor (const char *name, core::style::Style *style); - void addSpace(core::style::Style *style); + void addSpace (core::style::Style *style); + + inline void addBreakOption (core::style::Style *style) + { + int wordIndex = words->size () - 1; + if (wordIndex >= 0) + addBreakOption (words->getRef(wordIndex), style); + } + + // TODO Re-evaluate again. When needed, which penalty values, etc. + inline void addBreakOption (Word *word, core::style::Style *style) + { + if (style->whiteSpace != core::style::WHITE_SPACE_NOWRAP && + style->whiteSpace != core::style::WHITE_SPACE_PRE) + if (word->badnessAndPenalty.lineMustBeBroken()) + word->badnessAndPenalty.setPenalty (0); + } + + void addHyphen(); void addParbreak (int space, core::style::Style *style); void addLinebreak (core::style::Style *style); |