[Kst] kdeextragear-2/kst/kst

[George Staikos]

CVS commit by staikos: 

huge improvements in drawing performance - extremely noticeable.  drawing should
now be about 7 times faster.  I can still improve this by a factor of 4 or so
from where it is now by rewriting this code altogether.

other slow points are documented.


  M +32 -21    kstlabel.cpp   1.19


--- kdeextragear-2/kst/kst/kstlabel.cpp  #1.18:1.19
@@ -101,4 +101,5 @@ int KstLabel::ascent(QPainter &p) {
 }
 
+// FIXME: expensive - cache it?
 int KstLabel::lineSpacing(QPainter &p) {
   int LineSpacing = 0;
@@ -137,4 +138,7 @@ void KstLabel::draw(QPainter &p, int px,
   QString processedText;
 
+  // FIXME: This parsing is really slow.  We should cache the parse results.
+  //        We should also use a faster parsing algorithm.
+
   static const GreekCharType GC[] = {{"\\Alpha", "A"}, {"\\alpha", "a"},
                                      {"\\Beta", "B"}, {"\\beta", "b"},
@@ -245,9 +249,9 @@ void KstLabel::draw(QPainter &p, int px,
         i_fp++;
         fP[i_fp].locked = false;
-        fP[i_fp].size = fP[i_fp-1].size-1;
-        fP[i_fp].dy = fP[i_fp-1].dy + -p.fontMetrics().ascent()*0.4;
+        fP[i_fp].size = fP[i_fp-1].size - 1;
+        fP[i_fp].dy = fP[i_fp-1].dy - p.fontMetrics().ascent()*0.4;
         fP[i_fp].x = x;
         if (p.fontMetrics().rightBearing(C.at(0)) < 0) {
-          x -= 2.0*p.fontMetrics().rightBearing(C.at(0));
+          x -= 2.0 * p.fontMetrics().rightBearing(C.at(0));
         }
       }
@@ -277,6 +281,7 @@ void KstLabel::draw(QPainter &p, int px,
 
       is_greek = false;
+      QString subProcessedText = processedText.mid(i);
       for (i_g = 0; i_g < N_GREEK; i_g++) {
-        if (GC[i_g].label == processedText.mid(i, GC[i_g].label.length())) {
+        if (subProcessedText.startsWith(GC[i_g].label)) {
           is_greek = true;
           C = GC[i_g].c;
@@ -284,5 +289,5 @@ void KstLabel::draw(QPainter &p, int px,
           if (processedText[i+1] == ' ')
             i++;
-          i_g = N_GREEK;
+          break;
         }
       }
@@ -292,11 +298,12 @@ void KstLabel::draw(QPainter &p, int px,
         p.setFont(TextFont);
 
-        if (processedText.mid(i,2) == "\\_") {
+        if (processedText[i] == '\\') {
+          if (processedText[i+1] == '_') {
           C = "_";
           i++;
-        } else if (processedText.mid(i,2) == "\\^") {
+          } else if (processedText[i+1] == '^') {
           C = "^";
           i++;
-        } else if (processedText.mid(i,3) == "\\it") {
+          } else if (processedText[i+1] == 'i' && processedText[i+2] == 't') {
           TextFont.setItalic(true);
           i += 2;
@@ -304,5 +311,5 @@ void KstLabel::draw(QPainter &p, int px,
             i++;
           C = QString::null;
-        } else if (processedText.mid(i,3) == "\\rm") {
+          } else if (processedText[i+1] == 'r' && processedText[i+2] == 'm') {
           TextFont.setItalic(false);
           i += 2;
@@ -310,4 +317,8 @@ void KstLabel::draw(QPainter &p, int px,
             i++;
           C = QString::null;
+          } else {
+            C = processedText[i];
+            p.setFont(TextFont);
+          }
         } else {
           C = processedText[i];