ligatures: upgrading

hb.c

@@ -11,6 +11,7 @@
 #include "hb.h"
 
 #define FEATURE(c1,c2,c3,c4) { .tag = HB_TAG(c1,c2,c3,c4), .value = 1, .start = HB_FEATURE_GLOBAL_START, .end = HB_FEATURE_GLOBAL_END }
+#define BUFFER_STEP 256
 
 hb_font_t *hbfindfont(XftFont *match);
 
@@ -19,74 +20,109 @@ typedef struct {
 	hb_font_t *font;
 } HbFontMatch;
 
-static int hbfontslen = 0;
-static HbFontMatch *hbfontcache = NULL;
+typedef struct {
+	size_t capacity;
+	HbFontMatch *fonts;
+} HbFontCache;
+
+static HbFontCache hbfontcache = { 0, NULL };
+
+typedef struct {
+	size_t capacity;
+	Rune *runes;
+} RuneBuffer;
+
+static RuneBuffer hbrunebuffer = { 0, NULL };
+static hb_buffer_t *hbbuffer;
 
 /*
  * Poplulate the array with a list of font features, wrapped in FEATURE macro,
  * e. g.
  * FEATURE('c', 'a', 'l', 't'), FEATURE('d', 'l', 'i', 'g')
  */
-hb_feature_t features[] = { 0 };
+hb_feature_t features[] = { };
 
 void
-hbunloadfonts()
+hbcreatebuffer(void)
 {
-	for (int i = 0; i < hbfontslen; i++) {
-		hb_font_destroy(hbfontcache[i].font);
-		XftUnlockFace(hbfontcache[i].match);
+	hbbuffer = hb_buffer_create();
+}
+
+void
+hbdestroybuffer(void)
+{
+	hb_buffer_destroy(hbbuffer);
+}
+
+void
+hbunloadfonts(void)
+{
+	for (int i = 0; i < hbfontcache.capacity; i++) {
+		hb_font_destroy(hbfontcache.fonts[i].font);
+		XftUnlockFace(hbfontcache.fonts[i].match);
 	}
 
-	if (hbfontcache != NULL) {
-		free(hbfontcache);
-		hbfontcache = NULL;
+	if (hbfontcache.fonts != NULL) {
+		free(hbfontcache.fonts);
+		hbfontcache.fonts = NULL;
 	}
-	hbfontslen = 0;
+	hbfontcache.capacity = 0;
 }
 
 hb_font_t *
 hbfindfont(XftFont *match)
 {
-	for (int i = 0; i < hbfontslen; i++) {
-		if (hbfontcache[i].match == match)
-			return hbfontcache[i].font;
+	for (int i = 0; i < hbfontcache.capacity; i++) {
+		if (hbfontcache.fonts[i].match == match)
+			return hbfontcache.fonts[i].font;
 	}
 
 	/* Font not found in cache, caching it now. */
-	hbfontcache = realloc(hbfontcache, sizeof(HbFontMatch) * (hbfontslen + 1));
+	hbfontcache.fonts = realloc(hbfontcache.fonts, sizeof(HbFontMatch) * (hbfontcache.capacity + 1));
 	FT_Face face = XftLockFace(match);
 	hb_font_t *font = hb_ft_font_create(face, NULL);
 	if (font == NULL)
 		die("Failed to load Harfbuzz font.");
 
-	hbfontcache[hbfontslen].match = match;
-	hbfontcache[hbfontslen].font = font;
-	hbfontslen += 1;
+	hbfontcache.fonts[hbfontcache.capacity].match = match;
+	hbfontcache.fonts[hbfontcache.capacity].font = font;
+	hbfontcache.capacity += 1;
 
 	return font;
 }
 
-void hbtransform(HbTransformData *data, XftFont *xfont, const Glyph *glyphs, int start, int length) {
-	Rune rune;
-	ushort mode = USHRT_MAX;
+void
+hbtransform(HbTransformData *data, XftFont *xfont, const Glyph *glyphs, int start, int length)
+{
+	uint32_t mode;
 	unsigned int glyph_count;
-	int i, end = start + length;
+	int rune_idx, glyph_idx, end = start + length;
+	hb_buffer_t *buffer = hbbuffer;
 
 	hb_font_t *font = hbfindfont(xfont);
-	if (font == NULL)
+	if (font == NULL) {
+		data->count = 0;
 		return;
+	}
 
-	hb_buffer_t *buffer = hb_buffer_create();
+	hb_buffer_reset(buffer);
 	hb_buffer_set_direction(buffer, HB_DIRECTION_LTR);
+	hb_buffer_set_cluster_level(buffer, HB_BUFFER_CLUSTER_LEVEL_MONOTONE_CHARACTERS);
+
+	/* Resize the buffer if required length is larger. */
+	if (hbrunebuffer.capacity < length) {
+		hbrunebuffer.capacity = (length / BUFFER_STEP + 1) * BUFFER_STEP;
+		hbrunebuffer.runes = realloc(hbrunebuffer.runes, hbrunebuffer.capacity * sizeof(Rune));
+	}
 
 	/* Fill buffer with codepoints. */
-	for (i = start; i < end; i++) {
-		rune = glyphs[i].u;
-		mode = glyphs[i].mode;
+	for (rune_idx = 0, glyph_idx = start; glyph_idx < end; glyph_idx++, rune_idx++) {
+		hbrunebuffer.runes[rune_idx] = glyphs[glyph_idx].u;
+		mode = glyphs[glyph_idx].mode;
 		if (mode & ATTR_WDUMMY)
-			rune = 0x0020;
-		hb_buffer_add_codepoints(buffer, &rune, 1, 0, 1);
+			hbrunebuffer.runes[rune_idx] = 0x0020;
 	}
+	hb_buffer_add_codepoints(buffer, hbrunebuffer.runes, length, 0, length);
 
 	/* Shape the segment. */
 	hb_shape(font, buffer, features, sizeof(features)/sizeof(hb_feature_t));
@@ -95,14 +131,9 @@ void hbtransform(HbTransformData *data, XftFont *xfont, const Glyph *glyphs, int
 	hb_glyph_info_t *info = hb_buffer_get_glyph_infos(buffer, &glyph_count);
 	hb_glyph_position_t *pos = hb_buffer_get_glyph_positions(buffer, &glyph_count);
 
-	/** Fill the output. */
+	/* Fill the output. */
 	data->buffer = buffer;
 	data->glyphs = info;
 	data->positions = pos;
 	data->count = glyph_count;
 }
-
-void hbcleanup(HbTransformData *data) {
-	hb_buffer_destroy(data->buffer);
-	memset(data, 0, sizeof(HbTransformData));
-}