Speeding up the drawing, then all characters are known.

1 files changed, 99 insertions, 77 deletions

diff --git a/st.c b/st.c
index a440959..cc8a22a 100644
--- a/st.c
+++ b/st.c
@@ -437,7 +437,7 @@ typedef struct {
  */
 
 static Fontcache frc[256];
-static int frccur = 0, frclen = 0;
+static int frccur = -1, frclen = 0;
 
 ssize_t
 xwrite(int fd, char *s, size_t len) {
@@ -2410,7 +2410,7 @@ xunloadfonts(void)
                         ip = LEN(frc) - 1;
                 XftFontClose(xw.dpy, frc[ip].font);
         }
-        frccur = 0;
+        frccur = -1;
         frclen = 0;
 
         XftFontClose(xw.dpy, dc.font.match);
@@ -2532,11 +2532,12 @@ xinit(void) {
 void
 xdraws(char *s, Glyph base, int x, int y, int charlen, int bytelen) {
         int winx = borderpx + x * xw.cw, winy = borderpx + y * xw.ch,
-            width = charlen * xw.cw, u8clen, xp, i, frp, frcflags;
+            width = charlen * xw.cw, xp, i;
+        int frp, frcflags;
+        int u8fl, u8fblen, u8cblen, doesexist;
+        char *u8c, *u8fs;
         long u8char;
-        char *u8c;
         Font *font = &dc.font;
-        XftFont *sfont;
         FcResult fcres;
         FcPattern *fcpattern, *fontpattern;
         FcFontSet *fcsets[] = { NULL };
@@ -2608,11 +2609,6 @@ xdraws(char *s, Glyph base, int x, int y, int charlen, int bytelen) {
                 bg = temp;
         }
 
-        /* Width of the whole string that should be printed. */
-        XftTextExtentsUtf8(xw.dpy, font->match, (FcChar8 *)s, bytelen,
-                        &extents);
-        width = extents.xOff;
-
         /* Intelligent cleaning up of the borders. */
         if(x == 0) {
                 xclear(0, (y == 0)? 0 : winy, borderpx,
@@ -2630,85 +2626,111 @@ xdraws(char *s, Glyph base, int x, int y, int charlen, int bytelen) {
         /* Clean up the region we want to draw to. */
         XftDrawRect(xw.draw, bg, winx, winy, width, xw.ch);
 
-        /*
-         * Step through all UTF-8 characters one by one and search in the font
-         * cache ring buffer, whether there was some font found to display the
-         * unicode value of that UTF-8 character.
-         */
         fcsets[0] = font->set;
-        for (xp = winx; bytelen > 0; ) {
-                u8c = s;
-                u8clen = utf8decode(s, &u8char);
-                s += u8clen;
-                bytelen -= u8clen;
-
-                sfont = font->match;
+        for (xp = winx; bytelen > 0;) {
                 /*
-                 * Only check the font cache or load new fonts, if the
-                 * characters is not represented in main font.
+                 * Search for the range in the to be printed string of glyphs
+                 * that are in the main font. Then print that range. If
+                 * some glyph is found that is not in the font, do the
+                 * fallback dance.
                  */
-                if (!XftCharExists(xw.dpy, font->match, u8char)) {
-                        frp = frccur;
-                        /* Search the font cache. */
-                        for (i = 0; i < frclen; i++, frp--) {
-                                if (frp <= 0)
-                                        frp = LEN(frc) - 1;
+                u8fs = s;
+                u8fblen = 0;
+                u8fl = 0;
+                for (;;) {
+                        u8c = s;
+                        u8cblen = utf8decode(s, &u8char);
+                        s += u8cblen;
+                        bytelen -= u8cblen;
+
+                        doesexist = XftCharIndex(xw.dpy, font->match, u8char);
+                        if (!doesexist || bytelen <= 0) {
+                                if (bytelen <= 0) {
+                                        if (doesexist) {
+                                                u8fl++;
+                                                u8fblen += u8cblen;
+                                        }
+                                }
 
-                                if (frc[frp].c == u8char
-                                        && frc[frp].flags == frcflags) {
-                                        break;
+                                if (u8fl > 0) {
+                                        XftDrawStringUtf8(xw.draw, fg,
+                                                        font->match, xp,
+                                                        winy + font->ascent,
+                                                        (FcChar8 *)u8fs,
+                                                        u8fblen);
+                                        xp += font->width * u8fl;
                                 }
+                                break;
                         }
-                        if (i >= frclen) {
-                                /*
-                                 * Nothing was found in the cache. Now use
-                                 * some dozen of Fontconfig calls to get the
-                                 * font for one single character.
-                                 */
-                                fcpattern = FcPatternDuplicate(font->pattern);
-                                fccharset = FcCharSetCreate();
-
-                                FcCharSetAddChar(fccharset, u8char);
-                                FcPatternAddCharSet(fcpattern, FC_CHARSET,
-                                                fccharset);
-                                FcPatternAddBool(fcpattern, FC_SCALABLE,
-                                                FcTrue);
-
-                                FcConfigSubstitute(0, fcpattern,
-                                                FcMatchPattern);
-                                FcDefaultSubstitute(fcpattern);
-
-                                fontpattern = FcFontSetMatch(0, fcsets,
-                                                FcTrue, fcpattern, &fcres);
-
-                                frccur++;
-                                frclen++;
-                                if (frccur >= LEN(frc))
-                                        frccur = 0;
-                                if (frclen >= LEN(frc)) {
-                                        frclen = LEN(frc);
-                                        XftFontClose(xw.dpy, frc[frccur].font);
-                                }
 
-                                /*
-                                 * Overwrite or create the new cache entry
-                                 * entry.
-                                 */
-                                frc[frccur].font = XftFontOpenPattern(xw.dpy,
-                                                fontpattern);
-                                frc[frccur].c = u8char;
-                                frc[frccur].flags = frcflags;
+                        u8fl++;
+                        u8fblen += u8cblen;
+                }
+                if (doesexist)
+                        break;
 
-                                FcPatternDestroy(fcpattern);
-                                FcCharSetDestroy(fccharset);
+                frp = frccur;
+                /* Search the font cache. */
+                for (i = 0; i < frclen; i++, frp--) {
+                        if (frp <= 0)
+                                frp = LEN(frc) - 1;
 
-                                frp = frccur;
+                        if (frc[frp].c == u8char
+                                        && frc[frp].flags == frcflags) {
+                                break;
                         }
-                        sfont = frc[frp].font;
                 }
 
-                XftDrawStringUtf8(xw.draw, fg, sfont, xp, winy + sfont->ascent,
-                                (FcChar8 *)u8c, u8clen);
+                /* Nothing was found. */
+                if (i >= frclen) {
+                        /*
+                         * Nothing was found in the cache. Now use
+                         * some dozen of Fontconfig calls to get the
+                         * font for one single character.
+                         */
+                        fcpattern = FcPatternDuplicate(font->pattern);
+                        fccharset = FcCharSetCreate();
+
+                        FcCharSetAddChar(fccharset, u8char);
+                        FcPatternAddCharSet(fcpattern, FC_CHARSET,
+                                        fccharset);
+                        FcPatternAddBool(fcpattern, FC_SCALABLE,
+                                        FcTrue);
+
+                        FcConfigSubstitute(0, fcpattern,
+                                        FcMatchPattern);
+                        FcDefaultSubstitute(fcpattern);
+
+                        fontpattern = FcFontSetMatch(0, fcsets,
+                                        FcTrue, fcpattern, &fcres);
+
+                        /*
+                         * Overwrite or create the new cache entry
+                         * entry.
+                         */
+                        frccur++;
+                        frclen++;
+                        if (frccur >= LEN(frc))
+                                frccur = 0;
+                        if (frclen > LEN(frc)) {
+                                frclen = LEN(frc);
+                                XftFontClose(xw.dpy, frc[frccur].font);
+                        }
+
+                        frc[frccur].font = XftFontOpenPattern(xw.dpy,
+                                        fontpattern);
+                        frc[frccur].c = u8char;
+                        frc[frccur].flags = frcflags;
+
+                        FcPatternDestroy(fcpattern);
+                        FcCharSetDestroy(fccharset);
+
+                        frp = frccur;
+                }
+
+                XftDrawStringUtf8(xw.draw, fg, frc[frp].font,
+                                xp, winy + frc[frp].font->ascent,
+                                (FcChar8 *)u8c, u8cblen);
 
                 xp += font->width;
         }