diff options
| -rw-r--r-- | doc/dw-line-breaking.doc | 66 | ||||
| -rw-r--r-- | dw/hyphenator.cc | 2 | ||||
| -rw-r--r-- | dw/hyphenator.hh | 2 | ||||
| -rw-r--r-- | dw/textblock.cc | 8 | ||||
| -rw-r--r-- | dw/textblock.hh | 8 | ||||
| -rw-r--r-- | dw/textblock_linebreaking.cc | 8 | ||||
| -rw-r--r-- | lout/misc.hh | 2 | ||||
| -rw-r--r-- | test/notsosimplevector.cc | 2 |
8 files changed, 49 insertions, 49 deletions
diff --git a/doc/dw-line-breaking.doc b/doc/dw-line-breaking.doc index 8e520c62..afebf104 100644 --- a/doc/dw-line-breaking.doc +++ b/doc/dw-line-breaking.doc @@ -6,14 +6,14 @@ Should be incorporated into dw::Textblock.</div> <h2>Introduction</h2> -For the implementation of hyphenation in dillo, not only an +For the implementation of hyphenation in dillo, not only a hyphenation algorithm was implemented, but also, the line breaking was changed to a simple optimization per line. Aside from the improvement by this change per se, an important aspect is the introduction of "penalties". Before this change, dillo put all words into a line which fitted into it; now, a "badness" is calculated for a possible -breakpoint, and the best breakpoint, i. e. the breakoint with the -smallest value for "badness", is choosen. This can be simply refined +breakpoint, and the best breakpoint, i. e. the breakpoint with the +smallest value for "badness", is chosen. This can be simply refined to define "good" and "bad" breakpoints by assigning a "penalty"; the best breakpoint is then the one with the smallest value of "badness + penalty". Details can be found below. @@ -59,7 +59,7 @@ Anyway an interesting reading. <h3>Hyphenation</h3> -Dillo uses the algorithm by Frank Liang, which is described his +Dillo uses the algorithm by Frank Liang, which is described in his doctoral dissertation found at http://www.tug.org/docs/liang/. There is also a description in chapter H ("Hyphenation") of <i>The T<sub>E</sub>Xbook</i> by Donald E. Knuth, Addison-Wesley 1984. @@ -68,14 +68,14 @@ Pattern files can be found at http://www.ctan.org/tex-archive/language/hyphenation. -<h2>Overview over Changes</h2> +<h2>Overview of Changes</h2> Starting with this change, dw/textblock.cc has been split up; anything related to line breaking has been moved into dw/textblock_linebreaking.cc. This will also be done for other aspects like floats. (Better, however, would be a clean logical split.) -An important change relates to the way how lines are added: before, +An important change relates to the way that lines are added: before, dillo would add a line as soon as a new word for this line was added. Now, a line is added not before the <i>last</i> word of this line is known. This has two important implications: @@ -88,8 +88,8 @@ can be calculated simply in a loop. any line. For this reason, in some cases (e. g. in dw::Textblock::sizeRequestImpl) dw::Textblock::showMissingLines is called, which creates temporary lines, which must, under other -circumstances, removed again by dw::Textblock::removeTemporaryLines, -since they have been created based on limited informations, and so +circumstances, be removed again by dw::Textblock::removeTemporaryLines, +since they have been created based on limited information, and so possibly in a wrong way. (See below for details.) </ul> @@ -122,18 +122,18 @@ line-breaking: dw::Textblock::Word::origSpace. </ul> -In a more mathematical notation, the \f$i\f$th word has got a width +In a more mathematical notation, the \f$i\f$th word has a width \f$w_i\f$ and a space \f$s_i\f$. A break was possible, when there was a space between the two words, -and the first possible break was choosen. +and the first possible break was chosen. With hyphenation, the criteria are refined. Hyphenation should only be used when otherwise line breaking results in very large spaces. We define: <ul> -<li>the badness \f$\beta\f$ of a line, which is the greater the more the +<li>the badness \f$\beta\f$ of a line, which is greater the more the spaces between the words differ from the ideal space; <li>a penalty \f$p\f$ for any possible break point. </ul> @@ -155,8 +155,8 @@ So we need the following values: <ul> <li> \f$w_i\f$ (the width of the word \f$i\f$ itself); <li> \f$s_i\f$ (the width of the space following the word \f$i\f$); -<li> the strechability \f$y_i\f$, a value denoting how much the space -after word\f$i\f$ can be streched (typically \f${1\over 2} s_i\f$); +<li> the stretchability \f$y_i\f$, a value denoting how much the space +after word\f$i\f$ can be stretched (typically \f${1\over 2} s_i\f$); <li> the shrinkability \f$y_i\f$, a value denoting how much the space after word\f$i\f$ can be shrunken (typically \f${1\over 3} s_i\f$); <li> the penalty \f$p_i\f$, if the line is broken after word \f$i\f$; @@ -182,7 +182,7 @@ We define: \f[Z_a^b = \sum_{i=a}^{b-1} z_i\f] -\f$W_a^b\f$ is the total width, \f$Y_a^b\f$ the total strechability, and +\f$W_a^b\f$ is the total width, \f$Y_a^b\f$ the total stretchability, and \f$Z_a^b\f$ the total shrinkability. Furthermore the <i>adjustment ratio</i> \f$r_a^b\f$: @@ -206,13 +206,13 @@ The goal is to find the value of \f$b\f$ where \f$\beta_a^b + p_b\f$ is minimal. (\f$a\f$ is given, since we do not modify the previous lines.) -After a couple of words, it is not predictable weather this minimum +After a couple of words, it is not predictable whether this minimum has already been reached. There are two cases where this is possible for a given \f$b'\f$: <ul> <li>\f$\beta_{b'}^a = \infty\f$ (line gets too tight): \f$a \le b < -b'\f$, the minimun has to be searched between these two values; +b'\f$, the minimum has to be searched between these two values; <li>\f$p_{b'} = -\infty\f$ (forced line break): \f$a \le b \le b'\f$ (there may be another minimum of \f$\beta_a^b\f$ before; note the \f$\le\f$ instead of \f$<\f$). @@ -224,7 +224,7 @@ added to a line. For this reason, there are "temporary" lines already described above. (Note that the actual calculation differs from this description, since -integer arithmetics are used for performace, which make the actual +integer arithmetic is used for performance, which make the actual code more complicated. See dw::Textblock::BadnessAndPenalty for details.) @@ -240,11 +240,11 @@ not required that the width of text "AB" is identical to the width of "A" plus the width of "B", just for the reasons mentioned above. It gets even a bit more complicated, since it is required that a word part (instance of dw::Textblock::Word) has always the same length, -independant of whether hyphenation is applied or not. Furthermore, the +independent of whether hyphenation is applied or not. Furthermore, the hyphen length is fixed for a word; for practical reasons, it is always the width of a hyphen, in the given font. -For calculating the widths, consider a word of for syllables: +For calculating the widths, consider a word of four syllables: A-B-C-D. There are 3 hyphenation points, and so 2<sup>3</sup> = 8 possible ways of hyphenation: ABCD, ABC-D, AB-CD, AB-C-D, A-BCD, A-BC-D, A-B-CD, A-B-C-D. (Some of them, like the last one, are only @@ -252,8 +252,8 @@ probable for very narrow lines.) Let w(A), w(B), w(C), w(D) be the word widths (part of dw::Textblock::Word::size), which have to be calculated, and l be a -shorthand for of dw::core::Platform::textWidth. Without considering -this problem, the calculatin would be simple: w(A) = l(A) +shorthand for dw::core::Platform::textWidth. Without considering +this problem, the calculation would be simple: w(A) = l(A) etc. However, it gets a bit more complicated. Since all non-hyphenations are drawn as a whole, the following conditions can be concluded: @@ -289,7 +289,7 @@ near-perfect results, so this is kept simple. When soft hyphens are used, words are immediately divided into different parts, and so different instances of -dw::Textblock::Word. Atomatic hyphenation (using Liang's algorithm) +dw::Textblock::Word. Automatic hyphenation (using Liang's algorithm) is, however, not applied always, but only when possibly needed, after calculating a line without hyphenation: @@ -298,7 +298,7 @@ calculating a line without hyphenation: possibly this will result in a line with less parts of this word, and so a less tight line. <li>When the line is loose, and there is another word (for the -next line) availible, this word is hyphenated; possibly, some parts of +next line) available, this word is hyphenated; possibly, some parts of this word are taken into this line, making it less loose. </ul> @@ -311,8 +311,8 @@ dw::Textblock::words. This word list is implemented as an array, which is dynamically increased; a simple approach would involve moving all of the <i>n</i> elements after position <i>i</i>, so <i>n</i> - <i>i</i> steps are necessary. This would not be a -problem, since O(n) steps are neccessary; however, this will be -neccessary again for the next hyphenated word (at the end of a +problem, since O(n) steps are necessary; however, this will be +necessary again for the next hyphenated word (at the end of a following line), and so on, so that (<i>n</i> - <i>i</i><sub>1</sub>) + (<i>n</i> - <i>i</i><sub>2</sub>) + ..., with @@ -376,7 +376,7 @@ Possible strategies to deal with this problem: words when calculating extremes. Since the minimal widths of all words are used to calculate the minimal width of the text block, the simplest approach will hyphenate all words. This would, of course, -eliminate the performace gains of the current lazy approach. +eliminate the performance gains of the current lazy approach. <li>The latter approach could be optimized in some ways. Examples: (i) If a word is already narrower than the current accumulated value for the minimal width, it makes no sense to hyphenate it. (ii) In other @@ -392,7 +392,7 @@ dw::Textblock::BadnessAndPenalty. <b>Other than justified text:</b> The calculation of badness is designed for justified text. For other alignments, it may be -modified. The point is the definition of strechibility and for the +modified. The point is the definition of stretchability and for the line. Consider left-aligned text. Most importantly, not the spaces between @@ -403,11 +403,11 @@ width, \f$l\f$ above), this space is zero, so it is not possible to shrink it further. For this reason, the shrinkability is now already set to 0. -On the other hand, there should be a strechability for the space on +On the other hand, there should be a stretchability for the space on the right border. However, only the spaces between the words have a -strechability; later, the differences are summed up and used to fill -the space on the right. This works, but is a bit unprecise, since the -strechability of the space on the right depends on the number of words +stretchability; later, the differences are summed up and used to fill +the space on the right. This works, but is a bit imprecise, since the +stretchability of the space on the right depends on the number of words in the line. (Likewise, if you modify the code to assign a positive value for the @@ -415,11 +415,11 @@ shrinkability for left-aligned text, the difference is summed up and used for the right border; since this difference is negative, the lines will, when spaces are shrunken, get too long!) -Analogue considerations must be made vor right-aligned and centered +Analogous considerations must be made for right-aligned and centered text. (For centered texts, there are two adjustable spaces.) <b>Hyphens in adjacent lines:</b> It should be simple to assign a larger penalty for hyphens, when the line before is already -hyphenated. This way, hyphens in adjacent are penalized further. +hyphenated. This way, hyphens in adjacent lines are penalized further. */ diff --git a/dw/hyphenator.cc b/dw/hyphenator.cc index 0fbdb699..97844538 100644 --- a/dw/hyphenator.cc +++ b/dw/hyphenator.cc @@ -47,7 +47,7 @@ Hyphenator::Hyphenator (core::Platform *platform, fclose (patF); } - exceptions = NULL; // Again, only instanciated when needed. + exceptions = NULL; // Again, only instantiated when needed. FILE *excF = fopen (excFile, "r"); if (excF) { diff --git a/dw/hyphenator.hh b/dw/hyphenator.hh index bf123e5a..47530467 100644 --- a/dw/hyphenator.hh +++ b/dw/hyphenator.hh @@ -18,7 +18,7 @@ private: /* * Actually, only one method in Platform is needed: * textToLower(). And, IMO, this method is actually not platform - * independant, but based on UTF-8. Clarify? Change? + * independent, but based on UTF-8. Clarify? Change? */ core::Platform *platform; lout::container::typed::HashTable <lout::object::Integer, diff --git a/dw/textblock.cc b/dw/textblock.cc index c66fac23..a6a88518 100644 --- a/dw/textblock.cc +++ b/dw/textblock.cc @@ -298,7 +298,7 @@ void Textblock::getExtremesImpl (core::Extremes *extremes) // role. parMin += wordExtremes.minWidth + word->origSpace; - // Maximum: between two *neccessary* breaks (or at the end). + // Maximum: between two *necessary* breaks (or at the end). if (word->badnessAndPenalty.lineMustBeBroken () || atLastWord) { parMax += wordExtremes.maxWidth + word->hyphenWidth; extremes->maxWidth = misc::max (extremes->maxWidth, parMax); @@ -480,7 +480,7 @@ void Textblock::markChange (int ref) calls "queueResize (-1, true)", when no rewrapping is necessary; and (ii) a word may have parentRef == -1 , when it is not yet added to a line. In the latter case, nothing has to be done - now, but addLine(...) will do everything neccessary. */ + now, but addLine(...) will do everything necessary. */ if (ref != -1) { if (wrapRef == -1) wrapRef = ref; @@ -906,7 +906,7 @@ void Textblock::drawWord (Line *line, int wordIndex1, int wordIndex2, drawWord0 (wordIndex1, wordIndex2, word->content.text, word->size.width, style, view, area, xWidget, yWidgetBase); } else { - // Concaternate all words in a new buffer. + // Concatenate all words in a new buffer. int l = 0, totalWidth = 0; for (int i = wordIndex1; i <= wordIndex2; i++) { Word *w = words->getRef (i); @@ -1424,7 +1424,7 @@ void Textblock::addText (const char *text, size_t len, numHyphens++; if (numHyphens == 0) { - // Simple (and often) case: no soft hyphens. May still be hyphenated + // Simple (and common) case: no soft hyphens. May still be hyphenated // automatically. core::Requisition size; calcTextSize (text, len, style, &size); diff --git a/dw/textblock.hh b/dw/textblock.hh index 0c3c6870..12950ec3 100644 --- a/dw/textblock.hh +++ b/dw/textblock.hh @@ -147,7 +147,7 @@ private: /** * 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 + * integer arithmetic (floating point arithmetic avoided for * performance reasons). Unfortunately, the value range of the * badness is not well defined, so fiddling with the penalties is a * bit difficult. @@ -210,7 +210,7 @@ private: protected: enum { /** - * The penalty for hyphens, multiplied with 100. So, 100 means + * The penalty for hyphens, multiplied by 100. So, 100 means * 1.0. See dw::Textblock::BadnessAndPenalty::setPenalty for * more details. */ @@ -276,14 +276,14 @@ protected: * 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. */ + * whether 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; plus the hyphen width of this word (but of course, no hyphen widths of previous words. In other words: the value compared to the diff --git a/dw/textblock_linebreaking.cc b/dw/textblock_linebreaking.cc index 8fb577d1..48acc5b8 100644 --- a/dw/textblock_linebreaking.cc +++ b/dw/textblock_linebreaking.cc @@ -92,7 +92,7 @@ void Textblock::BadnessAndPenalty::calcBadness (int totalWidth, int idealWidth, } /** - * Sets the penalty, multiplied with 100. Multiplication is necessary + * Sets the penalty, multiplied by 100. Multiplication is necessary * to deal with fractional numbers, without having to use floating * point numbers. So, to set a penalty to 0.5, pass 50. * @@ -101,7 +101,7 @@ void Textblock::BadnessAndPenalty::calcBadness (int totalWidth, int idealWidth, * "Criteria for Line-Breaking". The exact calculation may vary, but * this definition of should be rather stable: (i) A perfectly * fitting line has a badness of 0. (ii) A line, where all spaces - * are extended by exactly the stretchabilty, as well as a line, where + * are extended by exactly the stretchability, as well as a line, where * all spaces are reduced by the shrinkability, have a badness of 1. */ void Textblock::BadnessAndPenalty::setPenalty (int penalty) @@ -577,9 +577,9 @@ void Textblock::wordWrap (int wordIndex, bool wrapAll) firstIndex, breakPos); lineAdded = true; } else { - // TODO hyphenateWord() should return weather something has + // TODO hyphenateWord() should return whether something has // changed at all. So that a second run, with - // !word->canBeHyphenated, is unneccessary. + // !word->canBeHyphenated, is unnecessary. // TODO Update: for this, searchUntil == 0 should be checked. PRINTF ("[%p] old searchUntil = %d ...\n", this, searchUntil); int n = hyphenateWord (hyphenatedWord); diff --git a/lout/misc.hh b/lout/misc.hh index f877c879..fe5cdcd5 100644 --- a/lout/misc.hh +++ b/lout/misc.hh @@ -262,7 +262,7 @@ public: * O(n). * * The basic idea is to keep an extra array (actually two, of which - * the second one is used temporally), which is inserted in a logical + * the second one is used temporarily), which is inserted in a logical * way. Since there is only one extra array at max, reading is rather * simple and fast (see NotSoSimpleVector::getRef): check whether the * position is before, within, or after the extra array. The first diff --git a/test/notsosimplevector.cc b/test/notsosimplevector.cc index 228734ee..1398c191 100644 --- a/test/notsosimplevector.cc +++ b/test/notsosimplevector.cc @@ -3,7 +3,7 @@ static void print (lout::misc::NotSoSimpleVector<int> *v) { for (int i = 0; i < v->size(); i++) { - // Uncomment für debugging, after making the respective members public. + // Uncomment for debugging, after making the respective members public. //if (v->startExtra != -1 && i == v->startExtra + v->numExtra) // printf (" ]"); if (i > 0) |