xtext: Always use Pango to get correct glyph width on Unix

This should be slower but pango seems to be reasonably fast
on Unix though extremely slow on Windows.

https://bugzilla.redhat.com/show_bug.cgi?id=1536298
This commit is contained in:
Peng Wu 2018-02-01 18:52:16 -05:00 committed by Patrick Griffis
parent 4cdf6460b6
commit d3f1ab7813

View File

@ -157,7 +157,10 @@ static char * gtk_xtext_get_word (GtkXText * xtext, int x, int y, textentry ** r
#define EMPH_BOLD 2
#define EMPH_HIDDEN 4
static PangoAttrList *attr_lists[4];
#ifdef G_OS_WIN32
/* the fontwidths variable is used on Windows only. */
static int fontwidths[4][128];
#endif
static PangoAttribute *
xtext_pango_attr (PangoAttribute *attr)
@ -170,7 +173,10 @@ xtext_pango_attr (PangoAttribute *attr)
static void
xtext_pango_init (GtkXText *xtext)
{
int i, j;
int i;
#ifdef G_OS_WIN32
int j;
#endif
char buf[2] = "\000";
if (attr_lists[0])
@ -202,6 +208,7 @@ xtext_pango_init (GtkXText *xtext)
break;
}
#ifdef G_OS_WIN32
/* Now initialize fontwidths[i] */
pango_layout_set_attributes (xtext->layout, attr_lists[i]);
for (j = 0; j < 128; j++)
@ -210,8 +217,14 @@ xtext_pango_init (GtkXText *xtext)
pango_layout_set_text (xtext->layout, buf, 1);
pango_layout_get_pixel_size (xtext->layout, &fontwidths[i][j], NULL);
}
#endif
}
xtext->space_width = fontwidths[0][' '];
/* re-compute space_width without using fontwidths */
pango_layout_set_attributes (xtext->layout, attr_lists[0]);
buf[0] = ' ';
pango_layout_set_text (xtext->layout, buf, 1);
pango_layout_get_pixel_size (xtext->layout, &(xtext->space_width), NULL);
}
static void
@ -289,8 +302,10 @@ static int
backend_get_text_width_emph (GtkXText *xtext, guchar *str, int len, int emphasis)
{
int width;
#ifdef G_OS_WIN32
int deltaw;
int mbl;
#endif
if (*str == 0)
return 0;
@ -301,6 +316,8 @@ backend_get_text_width_emph (GtkXText *xtext, guchar *str, int len, int emphasis
width = 0;
pango_layout_set_attributes (xtext->layout, attr_lists[emphasis]);
#ifdef G_OS_WIN32
while (len > 0)
{
mbl = charlen(str);
@ -315,6 +332,12 @@ backend_get_text_width_emph (GtkXText *xtext, guchar *str, int len, int emphasis
str += mbl;
len -= mbl;
}
#else
/* This code is slow on Windows,
but it will get the correct width from pango on Linux. */
pango_layout_set_text (xtext->layout, str, len);
pango_layout_get_pixel_size (xtext->layout, &width, NULL);
#endif
return width;
}