* matra for the Indic shaper.
*/
+static void
+output_glyph (hb_ot_shape_context_t *c,
+ hb_codepoint_t glyph)
+{
+ hb_buffer_t *buffer = c->buffer;
+
+ buffer->output_glyph (glyph);
+ hb_glyph_info_set_unicode_props (&buffer->out_info[buffer->out_len - 1], buffer->unicode);
+}
static bool
decompose (hb_ot_shape_context_t *c,
- bool recompose,
+ bool shortest,
hb_codepoint_t ab)
{
hb_codepoint_t a, b, glyph;
- bool has_this = hb_font_get_glyph (c->font, ab, 0, &glyph);
-
- /* If recomposing and the single char is supported by the font, we're good. */
- if (recompose && has_this)
- return TRUE;
- if (hb_unicode_decompose (c->buffer->unicode, ab, &a, &b) &&
- hb_font_get_glyph (c->font, b, 0, &glyph) &&
- decompose (c, recompose, a))
- {
- /* Successfully decomposed. */
+ if (!hb_unicode_decompose (c->buffer->unicode, ab, &a, &b) ||
+ (b && !hb_font_get_glyph (c->font, b, 0, &glyph)))
+ return FALSE;
- if (recompose) {
- /* Try composing b with base if not blocked */
+ bool has_a = hb_font_get_glyph (c->font, a, 0, &glyph);
+ if (shortest && has_a) {
+ /* Output a and b */
+ output_glyph (c, a);
+ if (b)
+ output_glyph (c, b);
+ return TRUE;
+ }
- }
+ if (decompose (c, shortest, a)) {
+ if (b)
+ output_glyph (c, b);
+ return TRUE;
+ }
+ if (has_a) {
+ output_glyph (c, a);
+ if (b)
+ output_glyph (c, b);
return TRUE;
}
- return has_this;
+ return FALSE;
}
-static bool
-decompose_single_char_cluster (hb_ot_shape_context_t *c,
- bool recompose,
- unsigned int i)
+static void
+decompose_current_glyph (hb_ot_shape_context_t *c,
+ bool shortest)
{
-// c->buffer->copy ();
-// bool ret = decompose (c, recompose, c->buffer->info[i].codepoint);
-// c->buffer->skip ();
-// return ret;
- return FALSE;
+ if (decompose (c, shortest, c->buffer->info[c->buffer->idx].codepoint))
+ c->buffer->skip_glyph ();
+ else
+ c->buffer->next_glyph ();
}
static void
-handle_single_char_cluster (hb_ot_shape_context_t *c,
- bool recompose,
- unsigned int i)
+decompose_single_char_cluster (hb_ot_shape_context_t *c,
+ bool will_recompose)
{
- /* Decompose */
- decompose_single_char_cluster (c, recompose, i);
+ hb_codepoint_t glyph;
+
+ /* If recomposing and font supports this, we're good to go */
+ if (will_recompose && hb_font_get_glyph (c->font, c->buffer->info[c->buffer->idx].codepoint, 0, &glyph)) {
+ c->buffer->next_glyph ();
+ return;
+ }
+
+ decompose_current_glyph (c, will_recompose);
}
static void
-handle_multi_char_cluster (hb_ot_shape_context_t *c,
- bool recompose,
- unsigned int start,
- unsigned int end)
+decompose_multi_char_cluster (hb_ot_shape_context_t *c,
+ unsigned int end)
{
/* TODO Currently if there's a variation-selector we give-up, it's just too hard. */
- for (unsigned int i = start; i < end; i++)
+ for (unsigned int i = c->buffer->idx; i < end; i++)
if (unlikely (is_variation_selector (c->buffer->info[i].codepoint)))
return;
+ while (c->buffer->idx < end)
+ decompose_current_glyph (c, FALSE);
+}
+
+static int
+compare_combining_class (const hb_glyph_info_t *pa, const hb_glyph_info_t *pb)
+{
+ unsigned int a = pa->combining_class();
+ unsigned int b = pb->combining_class();
+
+ return a < b ? -1 : a == b ? 0 : +1;
}
void
{
hb_buffer_t *buffer = c->buffer;
bool recompose = !hb_ot_shape_complex_prefer_decomposed (c->plan->shaper);
+ bool has_multichar_clusters = FALSE;
+ unsigned int count;
+
+ /* We do a fairly straightforward yet custom normalization process in three
+ * separate rounds: decompose, reorder, recompose (if desired). Currently
+ * this makes two buffer swaps. We can make it faster by moving the last
+ * two rounds into the inner loop for the first round, but it's more readable
+ * this way. */
+
+
+ /* First round, decompose */
buffer->clear_output ();
+ count = buffer->len;
+ for (buffer->idx = 0; buffer->idx < count;)
+ {
+ unsigned int end;
+ for (end = buffer->idx + 1; end < count; end++)
+ if (buffer->info[buffer->idx].cluster != buffer->info[end].cluster)
+ break;
+
+ if (buffer->idx + 1 == end)
+ decompose_single_char_cluster (c, recompose);
+ else {
+ decompose_multi_char_cluster (c, end);
+ has_multichar_clusters = TRUE;
+ }
+ }
+ buffer->swap_buffers ();
- unsigned int count = buffer->len;
- for (buffer->i = 0; buffer->i < count;)
+
+ /* Technically speaking, two characters with ccc=0 may combine. But all
+ * those cases are in languages that the indic module handles (which expects
+ * decomposed), or in Hangul jamo, which again, we want decomposed anyway.
+ * So we don't bother combining across cluster boundaries.
+ *
+ * TODO: Am I right about Hangul? If I am, we should add a Hangul module
+ * that requests decomposed. */
+
+ if (!has_multichar_clusters)
+ return; /* Done! */
+
+
+ /* Second round, reorder (inplace) */
+
+ count = buffer->len;
+ for (unsigned int i = 0; i < count; i++)
{
+ if (buffer->info[i].combining_class() == 0)
+ continue;
unsigned int end;
- for (end = buffer->i + 1; end < count; end++)
- if (buffer->info[buffer->i].cluster != buffer->info[end].cluster)
+ for (end = i + 1; end < count; end++)
+ if (buffer->info[end].combining_class() == 0)
break;
- if (buffer->i + 1 == end)
- handle_single_char_cluster (c, recompose, buffer->i);
- else
- handle_multi_char_cluster (c, recompose, buffer->i, end);
- while (buffer->i < end)
- c->buffer->next_glyph ();
+ /* We are going to do a bubble-sort. Only do this if the
+ * sequence is short. Doing it on long sequences can result
+ * in an O(n^2) DoS. */
+ if (end - i > 10) {
+ i = end;
+ continue;
+ }
+
+ hb_bubble_sort (buffer->info + i, end - i, compare_combining_class);
+
+ i = end;
+ }
+
+
+ if (!recompose)
+ return;
+
+ /* Third round, recompose */
+
+ /* As noted in the comment earlier, we don't try to combine
+ * ccc=0 chars with their previous Starter. */
+
+ buffer->clear_output ();
+ count = buffer->len;
+ unsigned int starter = 0;
+ buffer->next_glyph ();
+ while (buffer->idx < count)
+ {
+ if (buffer->info[buffer->idx].combining_class() == 0) {
+ starter = buffer->out_len;
+ buffer->next_glyph ();
+ continue;
+ }
+
+ hb_codepoint_t composed, glyph;
+ if ((buffer->out_info[buffer->out_len - 1].combining_class() >=
+ buffer->info[buffer->idx].combining_class()) ||
+ !hb_unicode_compose (c->buffer->unicode,
+ buffer->out_info[starter].codepoint,
+ buffer->info[buffer->idx].codepoint,
+ &composed) ||
+ !hb_font_get_glyph (c->font, composed, 0, &glyph))
+ {
+ /* Blocked, or doesn't compose. */
+ buffer->next_glyph ();
+ continue;
+ }
+
+ /* Composes. Modify starter and carry on. */
+ buffer->out_info[starter].codepoint = composed;
+ hb_glyph_info_set_unicode_props (&buffer->out_info[starter], buffer->unicode);
+
+ buffer->skip_glyph ();
}
+ buffer->swap_buffers ();
- buffer->swap ();
}
HB_END_DECLS
projects / profile / ivi / org.tizen.video-player.git / blobdiff