[libgnomekbd] Make all symbol drawings full-width, using alignment to place them

[Corentin Noël <corentinnoel src gnome org>]

commit 826cc95889b0a5bb2507d32a2960d2e4eac7a476
Author: Daniel Kahn Gillmor <dkg fifthhorseman net>
Date:   Sat Jan 8 11:48:43 2022 -0500

    Make all symbol drawings full-width, using alignment to place them
    
    Currently, left-displayed symbols (those produced without AltGr) are
    drawn on a key rendering in a full-width cell, but right-displayed
    symbols (those produced with AltGr) are only drawn in half-width cells
    on the key rendering.
    
    This means that left-displayed symbols can still overlap with
    right-hand symbols if they happen to be wide, but right-hand symbols
    are more likely to be truncated ("ellipsized").
    
    This change still allows the symbols to overlap, but makes
    right-displayed symbols less likely to be ellipsized.  We do this by
    using alignment to place right-displayed symbols to the right, instead
    of using a half-width cell.

 libgnomekbd/gkbd-keyboard-drawing.c | 45 +++++++++++++------------------------
 1 file changed, 15 insertions(+), 30 deletions(-)
---
diff --git a/libgnomekbd/gkbd-keyboard-drawing.c b/libgnomekbd/gkbd-keyboard-drawing.c
index 5d7c5ed..9271c69 100644
--- a/libgnomekbd/gkbd-keyboard-drawing.c
+++ b/libgnomekbd/gkbd-keyboard-drawing.c
@@ -927,6 +927,7 @@ draw_key_label_helper (GkbdKeyboardDrawingRenderContext * context,
                       gboolean is_pressed)
 {
        gint label_x, label_y, label_max_width, ycell;
+       PangoAlignment align;
 
        if (keysym == 0)
                return;
@@ -935,46 +936,30 @@ draw_key_label_helper (GkbdKeyboardDrawingRenderContext * context,
                (unsigned) keysym, (char) keysym, (int) glp);
 #endif
 
+       ycell = ((glp == GKBD_KEYBOARD_DRAWING_POS_BOTTOMLEFT) ||
+                (glp == GKBD_KEYBOARD_DRAWING_POS_BOTTOMRIGHT));
+       rotate_coordinate (x, y, x + padding,
+                          y + padding + (height -
+                                         2 * padding) *
+                          ycell * 4 / 7, angle, &label_x,
+                          &label_y);
+       label_max_width = PANGO_SCALE * (width - 2 * padding);
+
        switch (glp) {
        case GKBD_KEYBOARD_DRAWING_POS_TOPLEFT:
        case GKBD_KEYBOARD_DRAWING_POS_BOTTOMLEFT:
-               {
-                       ycell =
-                           glp == GKBD_KEYBOARD_DRAWING_POS_BOTTOMLEFT;
-
-                       rotate_coordinate (x, y, x + padding,
-                                          y + padding + (height -
-                                                         2 * padding) *
-                                          ycell * 4 / 7, angle, &label_x,
-                                          &label_y);
-                       label_max_width =
-                           PANGO_SCALE * (width - 2 * padding);
-                       break;
-               }
+                       align = PANGO_ALIGN_LEFT;
+               break;
        case GKBD_KEYBOARD_DRAWING_POS_TOPRIGHT:
        case GKBD_KEYBOARD_DRAWING_POS_BOTTOMRIGHT:
-               {
-                       ycell =
-                           glp == GKBD_KEYBOARD_DRAWING_POS_BOTTOMRIGHT;
-
-                       rotate_coordinate (x, y,
-                                          x + padding + (width -
-                                                         2 * padding) *
-                                          4 / 7,
-                                          y + padding + (height -
-                                                         2 * padding) *
-                                          ycell * 4 / 7, angle, &label_x,
-                                          &label_y);
-                       label_max_width =
-                           PANGO_SCALE * ((width - 2 * padding) -
-                                          (width - 2 * padding) * 4 / 7);
-                       break;
-               }
+                       align = PANGO_ALIGN_RIGHT;
+               break;
        default:
                return;
        }
        set_key_label_in_layout (context, keysym);
        pango_layout_set_width (context->layout, label_max_width);
+       pango_layout_set_alignment (context->layout, align);
        label_y -= (pango_layout_get_line_count (context->layout) - 1) *
            (pango_font_description_get_size (context->font_desc) /
             PANGO_SCALE);