/* Pango * shape.c: Convert characters into glyphs. * * Copyright (C) 1999 Red Hat Software * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */#include <config.h>#include "pango-impl-utils.h"#include "pango-glyph.h"#include "pango-engine-private.h"#include <string.h>/** * pango_shape: * @text:      the text to process * @length:    the length (in bytes) of @text * @analysis:  #PangoAnalysis structure from pango_itemize() * @glyphs:    glyph string in which to store results * * Given a segment of text and the corresponding * #PangoAnalysis structure returned from pango_itemize(), * convert the characters into glyphs. You may also pass * in only a substring of the item from pango_itemize(). */voidpango_shape (const gchar      *text,	     gint              length,	     const PangoAnalysis *analysis,	     PangoGlyphString *glyphs){  int i;  int last_cluster;  glyphs->num_glyphs = 0;  if (G_LIKELY (PANGO_IS_ENGINE_SHAPE (analysis->shape_engine) && PANGO_IS_FONT (analysis->font)))    {      _pango_engine_shape_shape (analysis->shape_engine, analysis->font,				 text, length, analysis, glyphs);      if (G_UNLIKELY (glyphs->num_glyphs == 0))	{	  /* If a font has been correctly chosen, but no glyphs are output,	   * there's probably something wrong with the shaper, or the font.	   *	   * Trying to be informative, we print out the font description,	   * shaper name, and the text, but to not flood the terminal with	   * zillions of the message, we set a flag to only err once per	   * font/engine pair.	   *	   * To do the flag fast, we use the engine qname to qflag the font,	   * but also the font description to flag the engine.  This is	   * supposed to be fast to check, but also avoid writing out	   * duplicate warnings when a new PangoFont is created.	   */	  GType engine_type = G_OBJECT_TYPE (analysis->shape_engine);	  GQuark warned_quark = g_type_qname (engine_type);	  if (!g_object_get_qdata (G_OBJECT (analysis->font), warned_quark))	    {	      PangoFontDescription *desc;	      char *font_name;	      const char *engine_name;	      desc = pango_font_describe (analysis->font);	      font_name = pango_font_description_to_string (desc);	      pango_font_description_free (desc);	      if (!g_object_get_data (G_OBJECT (analysis->shape_engine), font_name))	        {		  engine_name = g_type_name (engine_type);		  if (!engine_name)		    engine_name = "(unknown)";		  g_warning ("shaping failure, expect ugly output. shape-engine='%s', font='%s', text='%.*s'",			     engine_name,			     font_name,			     length == -1 ? (gint) strlen (text) : length, text);		  g_object_set_data_full (G_OBJECT (analysis->shape_engine), font_name,					  GINT_TO_POINTER (1), NULL);	        }	      g_free (font_name);	      g_object_set_qdata_full (G_OBJECT (analysis->font), warned_quark,				       GINT_TO_POINTER (1), NULL);	    }	}    }  else    {      if (!PANGO_IS_ENGINE_SHAPE (analysis->shape_engine) &&	  !_pango_warning_history.shape_shape_engine)	{	  _pango_warning_history.shape_shape_engine = TRUE;	  g_warning ("pango_shape called with bad shape_engine, expect ugly output");	}      if (!PANGO_IS_FONT (analysis->font) &&	  !_pango_warning_history.shape_font)	{	  _pango_warning_history.shape_font = TRUE;	  g_warning ("pango_shape called with bad font, expect ugly output");	}      glyphs->num_glyphs = 0;    }  if (!glyphs->num_glyphs)    {      PangoEngineShape *fallback_engine = _pango_get_fallback_shaper ();      _pango_engine_shape_shape (fallback_engine, analysis->font,				 text, length, analysis, glyphs);    }  /* make sure last_cluster is invalid */  last_cluster = glyphs->log_clusters[0] - 1;  for (i = 0; i < glyphs->num_glyphs; i++)    {     /* Set glyphs[i].attr.is_cluster_start based on log_clusters[]      */      if (glyphs->log_clusters[i] != last_cluster)	{	  glyphs->glyphs[i].attr.is_cluster_start = TRUE;	  last_cluster = glyphs->log_clusters[i];	}      else	glyphs->glyphs[i].attr.is_cluster_start = FALSE;      /* Shift glyph if width is negative, and negate width.       * This is useful for rotated font matrices and shouldn't       * harm in normal cases.       */      if (glyphs->glyphs[i].geometry.width < 0)	{	  glyphs->glyphs[i].geometry.width = -glyphs->glyphs[i].geometry.width;	  glyphs->glyphs[i].geometry.x_offset += glyphs->glyphs[i].geometry.width;	}    }}