diff options
Diffstat (limited to 'pango/mapping.c')
| -rw-r--r-- | pango/mapping.c | 171 |
1 files changed, 99 insertions, 72 deletions
diff --git a/pango/mapping.c b/pango/mapping.c index 470b2085..d075b9f8 100644 --- a/pango/mapping.c +++ b/pango/mapping.c @@ -32,12 +32,12 @@ #include <unicode.h> /** - * pango_cp_to_x: + * pango_glyph_string_index_to_x: + * @glyphs: the glyphs return from pango_shape() * @text: the text for the run * @length: the number of bytes (not characters) in @text. * @analysis: the analysis information return from pango_itemize() - * @glyphs: the glyphs return from pango_shape() - * @char_pos: the character position + * @index: the byte index within @text * @trailing: whether we should compute the result for the beginning * or end of the character (or cluster - the decision * for which may be script dependent). @@ -48,22 +48,27 @@ */ void -pango_cp_to_x (gchar *text, - gint length, - PangoAnalysis *analysis, - PangoGlyphString *glyphs, - gint char_pos, - gboolean trailing, - gint *x_pos) +pango_glyph_string_index_to_x (PangoGlyphString *glyphs, + char *text, + int length, + PangoAnalysis *analysis, + int index, + gboolean trailing, + int *x_pos) { - gint i; - gint start_xpos = 0; - gint end_xpos = 0; - gint width = 0; + int i; + int start_xpos = 0; + int end_xpos = 0; + int width = 0; + + int start_index = -1; + int end_index = -1; - gint start_char = -1; - gint end_char = -1; + int cluster_chars = 0; + int cluster_offset = 0; + char *p; + g_return_if_fail (glyphs != NULL); g_return_if_fail (length >= 0); g_return_if_fail (length == 0 || text != NULL); @@ -87,16 +92,16 @@ pango_cp_to_x (gchar *text, for (i = glyphs->num_glyphs - 1; i >= 0; i--) { - if (glyphs->log_clusters[i] > char_pos) + if (glyphs->log_clusters[i] > index) { - end_char = glyphs->log_clusters[i]; + end_index = glyphs->log_clusters[i]; end_xpos = width; break; } - if (start_char == -1 || glyphs->log_clusters[i] != start_char) + if (glyphs->log_clusters[i] != start_index) { - start_char = glyphs->log_clusters[i]; + start_index = glyphs->log_clusters[i]; start_xpos = width; } @@ -107,16 +112,16 @@ pango_cp_to_x (gchar *text, { for (i = 0; i < glyphs->num_glyphs; i++) { - if (glyphs->log_clusters[i] > char_pos) + if (glyphs->log_clusters[i] > index) { - end_char = glyphs->log_clusters[i]; + end_index = glyphs->log_clusters[i]; end_xpos = width; break; } - if (start_char == -1 || glyphs->log_clusters[i] != start_char) + if (glyphs->log_clusters[i] != start_index) { - start_char = glyphs->log_clusters[i]; + start_index = glyphs->log_clusters[i]; start_xpos = width; } @@ -124,36 +129,43 @@ pango_cp_to_x (gchar *text, } } - /* We need the character index of one past the end of the - * string, and so we have to recalculate the entire length - * of the string... - */ - if (end_char == -1) + if (end_index == -1) { - end_char = unicode_strlen (text, length); + end_index = length; end_xpos = (analysis->level % 2) ? 0 : width; } + /* Calculate offset of character within cluster */ + + p = text + start_index; + while (p < text + end_index) + { + p = unicode_next_utf8 (p); + if (p < text + index) + cluster_offset++; + cluster_chars++; + } + /* Now interpolate the result. For South Asian languages * we actually shouldn't iterpolate */ if (trailing) - char_pos += 1; + cluster_offset += 1; - *x_pos = (((double)(end_char - char_pos)) * start_xpos + - ((double)(char_pos - start_char)) * end_xpos) / - (end_char - start_char); + *x_pos = (((double)(cluster_chars - cluster_offset)) * start_xpos + + ((double)cluster_offset) * end_xpos) / + cluster_chars; } /** - * pango_x_to_cp: + * pango_glyph_string_x_to_index: + * @glyphs: the glyphs return from pango_shape() * @text: the text for the run * @length: the number of bytes (not characters) in text. * @analysis: the analysis information return from pango_itemize() - * @glyphs: the glyphs return from pango_shape() - * @x_pos: location to store the returned x character position - * @char_pos: location to store calculated character position. + * @x_pos: the x offset (in thousands of a device unit) + * @index: location to store calculated byte index within @text * @trailing: location to store a integer indicating where * in the cluster the user clicked. If the script * allows positioning within the cluster, it is either @@ -161,25 +173,27 @@ pango_cp_to_x (gchar *text, * of characters in the cluster. In either case * 0 represents the trailing edge of the cluster. * - * Converts from x position to x character. (X position - * is measured from the left edge of the run) + * Convert from x offset to position. */ void -pango_x_to_cp (gchar *text, - gint length, - PangoAnalysis *analysis, - PangoGlyphString *glyphs, - gint x_pos, - gint *char_pos, - gint *trailing) +pango_glyph_string_x_to_index (PangoGlyphString *glyphs, + char *text, + int length, + PangoAnalysis *analysis, + int x_pos, + int *index, + int *trailing) { - gint i; - gint start_xpos = 0; - gint end_xpos = 0; - gint width = 0; + int i; + int start_xpos = 0; + int end_xpos = 0; + int width = 0; + + int start_index = -1; + int end_index = -1; - gint start_char = -1; - gint end_char = -1; + int cluster_chars = 0; + char *p; gboolean found = FALSE; @@ -194,17 +208,17 @@ pango_x_to_cp (gchar *text, for (i = glyphs->num_glyphs - 1; i >= 0; i--) { - if (start_char == -1 || glyphs->log_clusters[i] != start_char) + if (glyphs->log_clusters[i] != start_index) { if (found) { - end_char = glyphs->log_clusters[i]; + end_index = glyphs->log_clusters[i]; end_xpos = width; break; } else { - start_char = glyphs->log_clusters[i]; + start_index = glyphs->log_clusters[i]; start_xpos = width; } } @@ -219,17 +233,17 @@ pango_x_to_cp (gchar *text, { for (i = 0; i < glyphs->num_glyphs; i++) { - if (start_char == -1 || glyphs->log_clusters[i] != start_char) + if (glyphs->log_clusters[i] != start_index) { if (found) { - end_char = glyphs->log_clusters[i]; + end_index = glyphs->log_clusters[i]; end_xpos = width; break; } else { - start_char = glyphs->log_clusters[i]; + start_index = glyphs->log_clusters[i]; start_xpos = width; } } @@ -241,31 +255,44 @@ pango_x_to_cp (gchar *text, } } - /* We need the character index of one past the end of the - * string, and so we have to recalculate the entire length - * of the string... - */ - if (end_char == -1) + if (end_index == -1) { - end_char = unicode_strlen (text, length); + end_index = length; end_xpos = (analysis->level % 2) ? 0 : width; } + /* Calculate number of chars within cluster */ + p = text + start_index; + while (p < text + end_index) + { + p = unicode_next_utf8 (p); + cluster_chars++; + } + if (start_xpos == end_xpos) { - if (char_pos) - *char_pos = start_char; + if (index) + *index = start_index; if (trailing) trailing = 0; } else { - double cp = (((double)(end_xpos - x_pos)) * start_char + - ((double)(x_pos - start_xpos)) * end_char) / - (end_xpos - start_xpos); + double cp = ((double)(x_pos - start_xpos) * cluster_chars) / (end_xpos - start_xpos); - if (char_pos) - *char_pos = (int)cp; + if (index) + { + char *p = text + start_index; + int i = 0; + + while (i + 1 < cp) + { + p = unicode_next_utf8 (p); + i++; + } + + *index = (p - text); + } if (trailing) *trailing = (cp - (int)cp) > 0.5 ? 1 : 0; } |