--- rxvt-unicode/src/rxvtfont.C	2021/06/17 19:42:55	1.207
+++ rxvt-unicode/src/rxvtfont.C	2021/06/18 22:12:30	1.211
@@ -1340,26 +1340,32 @@
 {
   careful = false;
 
-  rxvt_compose_expand_static<FcChar32> exp;
-  FcChar32 *chrs = exp (unicode);
-  int nchrs = exp.length (chrs);
+  // handle non-bmp chars when text_t is 16 bit
+#if ENABLE_COMBINING && !UNICODE_3
+  if (ecb_expect_false (IS_COMPOSE (unicode)))
+    if (compose_char *cc = rxvt_composite [unicode])
+      if (cc->c2 == NOCHAR)
+        unicode = cc->c1;
+      else
+        return false;
+    else
+      return false;
+#endif
+
+  FcChar32 chr = unicode;
 
-  // we handle the sequence if the first char is available
-  if (!XftCharExists (term->dpy, f, chrs [0]))
+  if (!XftCharExists (term->dpy, f, chr))
     return false;
 
   if (!prop || prop->width == rxvt_fontprop::unset)
     return true;
 
-  // but we check against the whole sequence bounding box
+  int wcw = max (WCWIDTH (chr), 1);
 
-  // check character against base font bounding box
-  FcChar32 ch = unicode;
   XGlyphInfo g;
-  XftTextExtents32 (term->dpy, f, chrs, nchrs, &g);
+  XftTextExtents32 (term->dpy, f, &chr, 1, &g);
 
   int w = g.width - g.x;
-  int wcw = max (WCWIDTH (chrs [0]), 1);
 
   careful = g.x > 0 || w > prop->width * wcw;
 
@@ -1378,10 +1384,8 @@
                      const text_t *text, int len,
                      int fg, int bg)
 {
-  XGlyphInfo extents;
-  //XftGlyphSpec *enc = rxvt_temp_buf<XftGlyphSpec> (len);//D
-  //XftGlyphSpec *ep = enc;//D
-  static vector<XftGlyphSpec> enc; enc.resize (0); // static to avoid malloc, still slow
+  XftGlyphSpec *enc = rxvt_temp_buf<XftGlyphSpec> (len);
+  XftGlyphSpec *ep = enc;
 
   dTermDisplay;
   dTermGC;
@@ -1402,36 +1406,57 @@
   while (len)
     {
       int cwidth = term->fwidth;
+      FcChar32 chr = *text++; len--;
 
-      rxvt_compose_expand_static<FcChar32> exp;
-      FcChar32 *chrs = exp (*text++); len--;
-      int nchrs = exp.length (chrs);
+      // handle non-bmp chars when text_t is 16 bit
+      #if ENABLE_COMBINING && !UNICODE_3
+        if (ecb_expect_false (IS_COMPOSE (chr)))
+          if (compose_char *cc = rxvt_composite [chr])
+            if (cc->c2 == NOCHAR)
+              chr = cc->c1;
+      #endif
 
       while (len && *text == NOCHAR)
         text++, len--, cwidth += term->fwidth;
 
-      if (chrs [0] != ' ') // skip spaces
+      if (chr != ' ') // skip spaces
         {
-          FT_UInt glyphs [rxvt_compose_expand_static<FcChar32>::max_size];
+          #if 0
+          FT_UInt glyphs [decltype (exp)::max_size];
 
           for (int i = 0; i < nchrs; ++i)
             glyphs [i] = XftCharIndex (disp, f, chrs [i]);
 
-          XftGlyphExtents (disp, f, glyphs, nchrs, &extents);
-
-          XftGlyphSpec ep;
-
-          ep.x = x_ + (cwidth - extents.xOff >> 1);
-          ep.y = y_ + ascent;
-
-          if (extents.xOff == 0)
-            ep.x = x_ + cwidth;
-
           for (int i = 0; i < nchrs; ++i)
             {
-              ep.glyph = glyphs [i];
-              enc.push_back (ep);
+              XGlyphInfo ep;
+              XftGlyphExtents (disp, f, glyphs+i, 1, &ep);
+              printf ("gs %4x g %4x + %3d,%3d o %3d,%3d wh %3d,%3d\n", chrs[i],glyphs[i],ep.x,ep.y,ep.xOff,ep.yOff,ep.width,ep.height);
             }
+          #endif
+
+          FT_UInt glyph = XftCharIndex (disp, f, chr);
+          XGlyphInfo extents;
+          XftGlyphExtents (disp, f, &glyph, 1, &extents);
+
+          ep->glyph = glyph;
+          ep->x = x_;
+          ep->y = y_ + ascent;
+
+          // the xft font cell might differ from the terminal font cell,
+          // in which we use the average between the two
+          ep->x += cwidth - extents.xOff >> 1;
+
+          // xft/freetype represent combining characters as characters with zero
+          // width rendered over the previous character with some fonts, while
+          // in other fonts, they are considered normal characters, while yet
+          // in other fonts, they are shifted all over the place.
+          // we handle the first two cases by keying off on xOff being 0
+          // for zero-width chars. normally, we would add extents.xOff
+          // of the base chaarcter here, but we don't have that, so we use cwidth.
+          ep->x += extents.xOff ? 0 : cwidth;
+
+          ++ep;
         }
 
       x_ += cwidth;
@@ -1439,7 +1464,7 @@
 
   if (buffered)
     {
-      if (!enc.empty ())
+      if (ep != enc)
         {
           rxvt_drawable &d2 = d.screen->scratch_drawable (w, h);
 
@@ -1495,7 +1520,7 @@
 #endif
             XftDrawRect (d2, &term->pix_colors[bg >= 0 ? bg : Color_bg].c, 0, 0, w, h);
 
-          XftDrawGlyphSpec (d2, &term->pix_colors[fg].c, f, &enc[0], enc.size ());
+          XftDrawGlyphSpec (d2, &term->pix_colors[fg].c, f, enc, ep - enc);
           XCopyArea (disp, d2, d, gc, 0, 0, w, h, x, y);
         }
       else
@@ -1504,7 +1529,7 @@
   else
     {
       clear_rect (d, x, y, w, h, bg);
-      XftDrawGlyphSpec (d, &term->pix_colors[fg].c, f, &enc[0], enc.size ());
+      XftDrawGlyphSpec (d, &term->pix_colors[fg].c, f, enc, ep - enc);
     }
 }