[ghex] HexWidget: fix offsets redraw issue

[Logan Rathbone <larathbone src gnome org>]

commit 35e1bfe6abda1f84bdf99f2e50b33e16b0d28327
Author: Logan Rathbone <poprocks gmail com>
Date:   Mon Jan 3 01:54:50 2022 -0500

    HexWidget: fix offsets redraw issue
    
    Inaccurate number of lines of offsets would be drawn when the document
    was first loaded.
    
    Another thing was that any callbacks on state flags changed has been
    removed. This should probably not have been there to begin with, but did
    force some redraws. Removing that could cause other redraw issues I'm
    not aware of. So will need to monitor this and make sure things work as
    expected.

 src/gtkhex.c | 75 +++++++++++++++++++++++++++---------------------------------
 1 file changed, 34 insertions(+), 41 deletions(-)
---
diff --git a/src/gtkhex.c b/src/gtkhex.c
index 9e9f228..54fbe44 100644
--- a/src/gtkhex.c
+++ b/src/gtkhex.c
@@ -305,16 +305,6 @@ redo_action (GtkWidget *widget,
        }
 }
 
-static void
-state_flags_changed_cb (GtkWidget *widget, GtkStateFlags flags,
-               gpointer user_data)
-{
-       HexWidget *self = HEX_WIDGET(widget);
-
-       if (flags | GTK_STATE_FLAG_FOCUS_WITHIN)
-               gtk_widget_queue_draw (widget);
-}
-
 static void
 doc_undo_redo_cb (HexDocument *doc, gpointer user_data)
 {
@@ -751,6 +741,21 @@ show_cursor (HexWidget *self, gboolean show)
        self->cursor_shown = show;
 }
 
+inline static int
+get_hex_cpl (HexWidget *self)
+{
+       int hex_cpl;
+
+       if (! self->default_cpl)
+               hex_cpl = hex_widget_layout_get_hex_cpl (
+                               HEX_WIDGET_LAYOUT(self->layout_manager));
+       else
+               hex_cpl = hex_widget_layout_util_hex_cpl_from_ascii_cpl (
+                               self->default_cpl, self->group_type);
+
+       return hex_cpl;
+}
+
 static void
 render_highlights (HexWidget *self,
                cairo_t *cr,
@@ -780,12 +785,7 @@ render_highlights (HexWidget *self,
                layout = self->alayout;
        }
 
-       if (! self->default_cpl)
-               hex_cpl = hex_widget_layout_get_hex_cpl (
-                               HEX_WIDGET_LAYOUT(self->layout_manager));
-       else
-               hex_cpl = hex_widget_layout_util_hex_cpl_from_ascii_cpl (
-                               self->default_cpl, self->group_type);
+       hex_cpl = get_hex_cpl (self);
 
        y = cursor_line * self->char_height;
 
@@ -1148,6 +1148,18 @@ render_offsets (HexWidget *self,
 #undef BUFLEN
 #undef MIN_CPL
 
+static void
+allocate_buffer (HexWidget *self)
+{
+       GtkWidget *widget = GTK_WIDGET (self);
+       int hex_cpl = get_hex_cpl (self);
+
+       if (self->disp_buffer)
+               g_free (self->disp_buffer);
+
+       self->disp_buffer = g_malloc ((hex_cpl + 1) * (self->vis_lines + 1));
+}
+
 /* draw_func for the hex drawing area
  */
 static void
@@ -1165,6 +1177,7 @@ hex_draw (GtkDrawingArea *drawing_area,
         * required values:
         */
        recalc_displays (self);
+       allocate_buffer (self);
 
        /* Finally, we can do what we wanted to do to begin with: draw our hex
         * lines!
@@ -1182,6 +1195,8 @@ ascii_draw (GtkDrawingArea *drawing_area,
        HexWidget *self = HEX_WIDGET(user_data);
        g_return_if_fail(HEX_IS_WIDGET(self));
 
+       recalc_displays (self);
+       allocate_buffer (self);
        render_lines (self, cr, 0, self->vis_lines, VIEW_ASCII);
 }
 
@@ -1195,6 +1210,7 @@ offsets_draw (GtkDrawingArea *drawing_area,
        HexWidget *self = HEX_WIDGET(user_data);
        g_return_if_fail(HEX_IS_WIDGET(self));
 
+       recalc_displays (self);
        render_offsets (self, cr, 0, self->vis_lines);
 }
 
@@ -1206,16 +1222,8 @@ static void
 recalc_displays (HexWidget *self)
 {
        GtkWidget *widget = GTK_WIDGET (self);
-       int hex_cpl;
        gint64 payload_size;
 
-       if (! self->default_cpl)
-               hex_cpl = hex_widget_layout_get_hex_cpl (
-                               HEX_WIDGET_LAYOUT(self->layout_manager));
-       else
-               hex_cpl = hex_widget_layout_util_hex_cpl_from_ascii_cpl (
-                               self->default_cpl, self->group_type);
-
        payload_size = HEX_BUFFER_PAYLOAD (self->document);
 
        /*
@@ -1229,11 +1237,6 @@ recalc_displays (HexWidget *self)
                if (payload_size % self->cpl)
                        self->lines++;
        }
-
-       if (self->disp_buffer)
-               g_free (self->disp_buffer);
-       
-       self->disp_buffer = g_malloc ((hex_cpl + 1) * (self->vis_lines + 1));
 }
 
 static void
@@ -1282,7 +1285,7 @@ recalc_scrolling (HexWidget *self)
  * connected to value-changed signal of scrollbar's GtkAdjustment
  */
 static void
-display_scrolled (GtkAdjustment *adj, HexWidget *self)
+adj_value_changed_cb (GtkAdjustment *adj, HexWidget *self)
 {
        int dx, dy;
        
@@ -1294,13 +1297,6 @@ display_scrolled (GtkAdjustment *adj, HexWidget *self)
        hex_widget_update_all_auto_highlights (self);
        hex_widget_invalidate_all_highlights (self);
 
-       /* FIXME - this works, but feels hackish. The problem is, _snapshot_child
-        * does nothing if it 'detects' that a widget does not need to be redrawn
-        * which is what it seems to think re: our drawing areas on a scroll event.
-        */
-       gtk_widget_queue_draw (GTK_WIDGET(self->adisp));
-       gtk_widget_queue_draw (GTK_WIDGET(self->xdisp));
-       gtk_widget_queue_draw (GTK_WIDGET(self->offsets));
        gtk_widget_queue_draw (GTK_WIDGET(self));
 }
 
@@ -2856,9 +2852,6 @@ hex_widget_init (HexWidget *self)
 
        /* SETUP SIGNALS */
 
-       g_signal_connect (widget, "state-flags-changed",
-                       G_CALLBACK(state_flags_changed_cb), NULL);
-
        /* GESTURES */
 
        /* Whole HexWidget widget (for right-click context menu) */
@@ -2957,7 +2950,7 @@ hex_widget_init (HexWidget *self)
        /* Connect signal for adjustment */
 
        g_signal_connect (self->adj, "value-changed",
-                                        G_CALLBACK (display_scrolled), self);
+                                        G_CALLBACK (adj_value_changed_cb), self);
 
        /* ACTIONS - Undo / Redo should start out disabled. */