master 7341e600b7b: Implement dots and dashes on PGTK

[Po Lu]

branch: master
commit 7341e600b7bc554df44784b6aa135bed8fcb61f1
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    Implement dots and dashes on PGTK
    
    * src/image.c (image_create_bitmap_from_file) [HAVE_PGTK]:
    Remove unused variable.
    
    * src/pgtkterm.c (pgtk_draw_dash, pgtk_fill_underline)
    (pgtk_draw_glyph_string): New functions, ported from X.
---
 src/image.c    |  1 -
 src/pgtkterm.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++++----------
 2 files changed, 76 insertions(+), 16 deletions(-)

diff --git a/src/image.c b/src/image.c
index ab61e49f695..b15d68bf9bf 100644
--- a/src/image.c
+++ b/src/image.c
@@ -766,7 +766,6 @@ image_create_bitmap_from_file (struct frame *f, Lisp_Object 
file)
   ptrdiff_t id, size;
   int fd, width, height, rc;
   char *contents, *data;
-  void *bitmap;
 
   if (!STRINGP (image_find_image_fd (file, &fd)))
     return -1;
diff --git a/src/pgtkterm.c b/src/pgtkterm.c
index 8441189ab8d..72bc636485a 100644
--- a/src/pgtkterm.c
+++ b/src/pgtkterm.c
@@ -53,7 +53,6 @@ along with GNU Emacs.  If not, see 
<https://www.gnu.org/licenses/>.  */
 #include "termhooks.h"
 #include "termopts.h"
 #include "termchar.h"
-#include "emacs-icon.h"
 #include "menu.h"
 #include "window.h"
 #include "keyboard.h"
@@ -1239,7 +1238,7 @@ pgtk_set_glyph_string_gc (struct glyph_string *s)
    line or menu if we don't have X toolkit support.  */
 
 static void
-pgtk_set_glyph_string_clipping (struct glyph_string *s, cairo_t * cr)
+pgtk_set_glyph_string_clipping (struct glyph_string *s, cairo_t *cr)
 {
   XRectangle r[2];
   int n = get_glyph_string_clip_rects (s, r, 2);
@@ -1260,7 +1259,7 @@ pgtk_set_glyph_string_clipping (struct glyph_string *s, 
cairo_t * cr)
 
 static void
 pgtk_set_glyph_string_clipping_exactly (struct glyph_string *src,
-                                       struct glyph_string *dst, cairo_t * cr)
+                                       struct glyph_string *dst, cairo_t *cr)
 {
   dst->clip[0].x = src->x;
   dst->clip[0].y = src->y;
@@ -2434,6 +2433,73 @@ pgtk_draw_stretch_glyph_string (struct glyph_string *s)
   s->background_filled_p = true;
 }
 
+
+/* Draw a dashed underline of thickness THICKNESS and width WIDTH onto F
+   at a vertical offset of OFFSET from the position of the glyph string
+   S, with each segment SEGMENT pixels in length.  */
+
+static void
+pgtk_draw_dash (struct frame *f, struct glyph_string *s,
+               unsigned long foreground, int width,
+               char segment, int offset, int thickness)
+{
+  cairo_t *cr;
+  double cr_segment, y_center;
+
+  cr = pgtk_begin_cr_clip (s->f);
+  pgtk_set_cr_source_with_color (f, foreground, false);
+  cr_segment = (double) segment;
+  y_center = s->ybase + offset + (thickness / 2.0);
+
+  cairo_set_dash (cr, &cr_segment, 1, s->x);
+  cairo_set_line_width (cr, thickness);
+  cairo_move_to (cr, s->x, y_center);
+  cairo_line_to (cr, s->x + width, y_center);
+  cairo_stroke (cr);
+  pgtk_end_cr_clip (f);
+}
+
+/* Draw an underline of STYLE onto F at an offset of POSITION from the
+   baseline of the glyph string S in the color provided by FOREGROUND,
+   DECORATION_WIDTH in length, and THICKNESS in height.  */
+
+static void
+pgtk_fill_underline (struct frame *f, struct glyph_string *s,
+                    unsigned long foreground,
+                    enum face_underline_type style, int position,
+                    int decoration_width, int thickness)
+{
+  int segment;
+
+  segment = thickness * 3;
+
+  switch (style)
+    {
+      /* FACE_UNDERLINE_DOUBLE_LINE is treated identically to SINGLE, as
+        the second line will be filled by another invocation of this
+        function.  */
+    case FACE_UNDERLINE_SINGLE:
+    case FACE_UNDERLINE_DOUBLE_LINE:
+      pgtk_fill_rectangle (f, foreground, s->x, s->ybase + position,
+                          decoration_width, thickness, false);
+      break;
+
+    case FACE_UNDERLINE_DOTS:
+      segment = thickness;
+      FALLTHROUGH;
+
+    case FACE_UNDERLINE_DASHES:
+      pgtk_draw_dash (f, s, foreground, decoration_width, segment,
+                     position, thickness);
+      break;
+
+    case FACE_NO_UNDERLINE:
+    case FACE_UNDERLINE_WAVE:
+    default:
+      emacs_abort ();
+    }
+}
+
 static void
 pgtk_draw_glyph_string (struct glyph_string *s)
 {
@@ -2553,17 +2619,14 @@ pgtk_draw_glyph_string (struct glyph_string *s)
              else
                pgtk_draw_underwave (s, s->face->underline_color);
            }
-         else if (s->face->underline == FACE_UNDERLINE_SINGLE
-                  || s->face->underline == FACE_UNDERLINE_DOUBLE_LINE)
+         else if (s->face->underline >= FACE_UNDERLINE_SINGLE)
            {
              unsigned long thickness, position;
-             int y;
              unsigned long foreground;
 
              if (s->prev
-                 && ((s->prev->face->underline == FACE_UNDERLINE_SINGLE)
-                     || (s->prev->face->underline
-                         == FACE_UNDERLINE_DOUBLE_LINE))
+                 && (s->prev->face->underline != FACE_UNDERLINE_WAVE
+                     && s->prev->face->underline >= FACE_UNDERLINE_SINGLE)
                  && (s->prev->face->underline_at_descent_line_p
                      == s->face->underline_at_descent_line_p)
                  && (s->prev->face->underline_pixels_above_descent_line
@@ -2619,15 +2682,14 @@ pgtk_draw_glyph_string (struct glyph_string *s)
                thickness = (s->y + s->height) - (s->ybase + position);
              s->underline_thickness = thickness;
              s->underline_position = position;
-             y = s->ybase + position;
 
              if (s->face->underline_defaulted_p)
                foreground = s->xgcv.foreground;
              else
                foreground = s->face->underline_color;
 
-             pgtk_fill_rectangle (s->f, foreground, s->x, y, s->width,
-                                  thickness, false);
+             pgtk_fill_underline (s->f, s, foreground, s->face->underline,
+                                  position, s->width, thickness);
 
              /* Place a second underline above the first if this was
                 requested in the face specification.  */
@@ -2636,9 +2698,8 @@ pgtk_draw_glyph_string (struct glyph_string *s)
                {
                  /* Compute the position of the second underline.  */
                  position = position - thickness - 1;
-                 y        = s->ybase + position;
-                 pgtk_fill_rectangle (s->f, foreground, s->x, y, s->width,
-                                      thickness, false);
+                 pgtk_fill_underline (s->f, s, foreground, s->face->underline,
+                                      position, s->width, thickness);
                }
            }
        }