[icu-le] Implement icu layout engine shaper

configure.ac

@@ -160,7 +160,7 @@ AM_CONDITIONAL(HAVE_ICU, $have_icu)
 
 dnl ==========================================================================
 
-PKG_CHECK_MODULES(ICU_LE, icu-le, have_icu_le=true, have_icu_le=false)
+PKG_CHECK_MODULES(ICU_LE, icu-le icu-uc, have_icu_le=true, have_icu_le=false)
 if $have_icu_le; then
 	AC_DEFINE(HAVE_ICU_LE, 1, [Have ICU Layout Engine library])
 fi

src/hb-icu-le.cc

@@ -30,14 +30,10 @@
 
 #include "hb-icu-le/PortableFontInstance.h"
 
-#include "layout/loengine.h"
+#include "layout/LayoutEngine.h"
+#include "unicode/unistr.h"
 
-#include <harfbuzz.h>
-
-
-#ifndef HB_DEBUG_ICU_LE
-#define HB_DEBUG_ICU_LE (HB_DEBUG+0)
-#endif
+#include "hb-icu.h"
 
 
 /*
@@ -93,8 +89,8 @@ struct hb_icu_le_shaper_shape_plan_data_t {};
 
 hb_icu_le_shaper_shape_plan_data_t *
 _hb_icu_le_shaper_shape_plan_data_create (hb_shape_plan_t    *shape_plan,
-				       const hb_feature_t *user_features,
-				       unsigned int        num_user_features)
+					  const hb_feature_t *user_features,
+					  unsigned int        num_user_features)
 {
   return (hb_icu_le_shaper_shape_plan_data_t *) HB_SHAPER_DATA_SUCCEEDED;
 }
@@ -116,5 +112,102 @@ _hb_icu_le_shape (hb_shape_plan_t    *shape_plan,
 		  const hb_feature_t *features,
 		  unsigned int        num_features)
 {
-  return false;
+  LEFontInstance *font_instance = HB_SHAPER_DATA_GET (font);
+  le_int32 script_code = hb_icu_script_from_script (shape_plan->props.script);
+  le_int32 language_code = -1 /* TODO */;
+  le_int32 typography_flags = 3; // essential for ligatures and kerning
+  LEErrorCode status = LE_NO_ERROR;
+  LayoutEngine *le = LayoutEngine::layoutEngineFactory (font_instance,
+							script_code,
+							language_code,
+							typography_flags,
+							status);
+  if (status != LE_NO_ERROR)
+  { delete (le); return false; }
+
+retry:
+
+  unsigned int scratch_size;
+  char *scratch = (char *) buffer->get_scratch_buffer (&scratch_size);
+
+#define ALLOCATE_ARRAY(Type, name, len) \
+  Type *name = (Type *) scratch; \
+  scratch += (len) * sizeof ((name)[0]); \
+  scratch_size -= (len) * sizeof ((name)[0]);
+
+  ALLOCATE_ARRAY (LEUnicode, chars, buffer->len);
+  ALLOCATE_ARRAY (unsigned int, clusters, buffer->len);
+
+  for (unsigned int i = 0; i < buffer->len; i++) {
+    chars[i] = buffer->info[i].codepoint;
+    clusters[i] = buffer->info[i].cluster;
+  }
+
+  unsigned int glyph_count = le->layoutChars(chars,
+					     0,
+					     buffer->len,
+					     buffer->len,
+					     HB_DIRECTION_IS_BACKWARD (buffer->props.direction),
+					     0., 0.,
+					     status);
+  if (status != LE_NO_ERROR)
+  { delete (le); return false; }
+
+  unsigned int num_glyphs = scratch_size / (sizeof (LEGlyphID) +
+					    sizeof (le_int32) +
+					    sizeof (float) * 2);
+
+  if (unlikely (glyph_count >= num_glyphs || glyph_count > buffer->allocated)) {
+    buffer->ensure (buffer->allocated * 2);
+    if (buffer->in_error)
+    { delete (le); return false; }
+    goto retry;
+  }
+
+  ALLOCATE_ARRAY (LEGlyphID, glyphs, glyph_count);
+  ALLOCATE_ARRAY (le_int32, indices, glyph_count);
+  ALLOCATE_ARRAY (float, positions, glyph_count * 2 + 2);
+
+  le->getGlyphs(glyphs, status);
+  le->getCharIndices(indices, status);
+  le->getGlyphPositions(positions, status);
+
+#undef ALLOCATE_ARRAY
+
+  /* Ok, we've got everything we need, now compose output buffer,
+   * very, *very*, carefully! */
+
+  unsigned int j = 0;
+  hb_glyph_info_t *info = buffer->info;
+  for (unsigned int i = 0; i < glyph_count; i++)
+  {
+    if (glyphs[i] >= 0xFFFE)
+	continue;
+
+    info[j].codepoint = glyphs[i];
+    info[j].cluster = clusters[indices[i]];
+
+    /* icu-le doesn't seem to have separapte advance values. */
+    info[j].mask = positions[2 * i + 2] - positions[2 * i];
+    info[j].var1.u32 = 0;
+    info[j].var2.u32 = -positions[2 * i + 1];
+
+    j++;
+  }
+  buffer->len = j;
+
+  buffer->clear_positions ();
+
+  for (unsigned int i = 0; i < buffer->len; i++) {
+    hb_glyph_info_t *info = &buffer->info[i];
+    hb_glyph_position_t *pos = &buffer->pos[i];
+
+    /* TODO vertical */
+    pos->x_advance = info->mask;
+    pos->x_offset = info->var1.u32;
+    pos->y_offset = info->var2.u32;
+  }
+
+  delete (le);
+  return true;
 }

src/hb-icu-le/cmaps.h

@@ -78,7 +78,6 @@ inline CMAPMapper::CMAPMapper(const CMAPTable *cmap)
 
 inline CMAPMapper::~CMAPMapper()
 {
-    DELETE_ARRAY(fcmap);
 }
 
 #endif

src/hb-shaper-list.hh

@@ -47,4 +47,8 @@ HB_SHAPER_IMPLEMENT (ot) /* <--- This is our main OpenType shaper. */
 HB_SHAPER_IMPLEMENT (old)
 #endif
 
+#ifdef HAVE_ICU_LE
+HB_SHAPER_IMPLEMENT (icu_le)
+#endif
+
 HB_SHAPER_IMPLEMENT (fallback) /* <--- This should be last. */