From 70f83679ee24bd01e7a0f481e23a7da0c10c9cfe Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Philipp=20Br=C3=BCschweiler?= <blei42@gmail.com>
Date: Tue, 2 Oct 2012 11:06:54 +0200
Subject: [PATCH] editor: more intuitive cursor positioning
Compute the nearest glyph edge instead of taking the one to the
left of the cursor.
Also fixes a segfault when trying to compute the position for an empty
buffer.
---
clients/editor.c | 18 +++++++++++++-----
1 file changed, 13 insertions(+), 5 deletions(-)
diff --git a/clients/editor.c b/clients/editor.c
index cade2629..ce0692fa 100644
--- a/clients/editor.c
+++ b/clients/editor.c
@@ -153,18 +153,26 @@ text_layout_xy_to_index(struct text_layout *layout, double x, double y)
{
cairo_text_extents_t extents;
int i;
+ double d;
+
+ if (layout->num_glyphs == 0)
+ return 0;
cairo_scaled_font_glyph_extents(layout->font,
layout->glyphs, layout->num_glyphs,
&extents);
- for (i = 1; i < layout->num_glyphs; i++) {
- if (layout->glyphs[i].x >= x) {
- return i - 1;
- }
+ if (x < 0)
+ return 0;
+
+ for (i = 0; i < layout->num_glyphs - 1; ++i) {
+ d = layout->glyphs[i + 1].x - layout->glyphs[i].x;
+ if (x < layout->glyphs[i].x + d/2)
+ return i;
}
- if (x >= layout->glyphs[layout->num_glyphs - 1].x && x < extents.width)
+ d = extents.width - layout->glyphs[layout->num_glyphs - 1].x;
+ if (x < layout->glyphs[layout->num_glyphs - 1].x + d/2)
return layout->num_glyphs - 1;
return layout->num_glyphs;