[vte] widget: Add font-scale property

[Christian Persch <chpe src gnome org>]

commit c818ee7445189cda4f5fa1dc19f676d91fbab7a7
Author: Christian Persch <chpe gnome org>
Date:   Fri May 27 23:49:37 2011 +0200

    widget: Add font-scale property
    
    To implement zoom, add font-scale property.
    
    Conflicts:
        src/vte-private.h
        src/vte.c
        src/vteapp.c

 doc/reference/vte-sections.txt |    3 +-
 src/vte-private.h              |    5 ++
 src/vte.c                      |  149 +++++++++++++++++++++++++++++-----------
 src/vte.h                      |    8 ++-
 src/vteapp.c                   |   31 +++-----
 5 files changed, 135 insertions(+), 61 deletions(-)
---
diff --git a/doc/reference/vte-sections.txt b/doc/reference/vte-sections.txt
index 4d75db4..de056d7 100644
--- a/doc/reference/vte-sections.txt
+++ b/doc/reference/vte-sections.txt
@@ -18,6 +18,8 @@ vte_terminal_paste_clipboard
 vte_terminal_copy_primary
 vte_terminal_paste_primary
 vte_terminal_set_size
+vte_terminal_set_font_scale
+vte_terminal_get_font_scale
 vte_terminal_set_audible_bell
 vte_terminal_get_audible_bell
 vte_terminal_set_visible_bell
@@ -43,7 +45,6 @@ vte_terminal_get_cursor_blink_mode
 vte_terminal_set_cursor_blink_mode
 vte_terminal_set_scrollback_lines
 vte_terminal_set_font
-vte_terminal_set_font_from_string
 vte_terminal_get_font
 vte_terminal_get_has_selection
 vte_terminal_set_word_chars
diff --git a/src/vte-private.h b/src/vte-private.h
index 045f3c5..831c53a 100644
--- a/src/vte-private.h
+++ b/src/vte-private.h
@@ -111,6 +111,9 @@ G_BEGIN_DECLS
 #define VTE_COLOR_SOURCE_ESCAPE 0
 #define VTE_COLOR_SOURCE_API 1
 
+#define VTE_FONT_SCALE_MIN (.25)
+#define VTE_FONT_SCALE_MAX (4.)
+
 #define I_(string) (g_intern_static_string(string))
 
 typedef enum {
@@ -351,7 +354,9 @@ struct _VteTerminalPrivate {
 
        /* Data used when rendering the text which does not require server
         * resources and which can be kept after unrealizing. */
+        PangoFontDescription *unscaled_font_desc;
        PangoFontDescription *fontdesc;
+        gdouble font_scale;
        gboolean fontdirty;
         glong char_ascent;
         glong char_descent;
diff --git a/src/vte.c b/src/vte.c
index d984d16..772e45b 100644
--- a/src/vte.c
+++ b/src/vte.c
@@ -168,7 +168,8 @@ enum {
         PROP_SCROLL_ON_OUTPUT,
         PROP_WINDOW_TITLE,
         PROP_WORD_CHARS,
-        PROP_VISIBLE_BELL
+        PROP_VISIBLE_BELL,
+        PROP_FONT_SCALE
 };
 
 /* these static variables are guarded by the GDK mutex */
@@ -7512,8 +7513,38 @@ vte_terminal_ensure_font (VteTerminal *terminal)
        }
 }
 
-/**
- * vte_terminal_set_font:
+static void
+vte_terminal_update_font(VteTerminal *terminal)
+{
+        VteTerminalPrivate *pvt = terminal->pvt;
+        PangoFontDescription *desc;
+        gdouble size;
+
+        desc = pango_font_description_copy(pvt->unscaled_font_desc);
+
+        size = pango_font_description_get_size(desc);
+        if (pango_font_description_get_size_is_absolute(desc)) {
+                pango_font_description_set_absolute_size(desc, pvt->font_scale * size);
+        } else {
+                pango_font_description_set_size(desc, pvt->font_scale * size);
+        }
+
+        if (pvt->fontdesc) {
+                pango_font_description_free(pvt->fontdesc);
+        }
+        pvt->fontdesc = desc;
+
+        pvt->fontdirty = TRUE;
+        pvt->has_fonts = TRUE;
+
+        /* Set the drawing font. */
+        if (gtk_widget_get_realized (&terminal->widget)) {
+                vte_terminal_ensure_font (terminal);
+        }
+}
+
+/*
+ * _vte_terminal_set_font:
  * @terminal: a #VteTerminal
  * @font_desc: (allow-none): a #PangoFontDescription for the desired font, or %NULL
  *
@@ -7559,72 +7590,82 @@ vte_terminal_set_font(VteTerminal *terminal,
                                "Using default monospace font.\n");
        }
 
-        same_desc = pvt->fontdesc && pango_font_description_equal (pvt->fontdesc, desc);
-       
+        same_desc = pvt->unscaled_font_desc &&
+                    pango_font_description_equal (pvt->unscaled_font_desc, desc);
+
        /* Note that we proceed to recreating the font even if the description
         * are the same.  This is because maybe screen
         * font options were changed, or new fonts installed.  Those will be
         * detected at font creation time and respected.
         */
 
-        g_object_freeze_notify(object);
-
        /* Free the old font description and save the new one. */
-       if (terminal->pvt->fontdesc != NULL) {
-               pango_font_description_free(terminal->pvt->fontdesc);
+       if (terminal->pvt->unscaled_font_desc != NULL) {
+               pango_font_description_free(terminal->pvt->unscaled_font_desc);
        }
-       pvt->fontdesc = desc;
-       pvt->fontdirty = TRUE;
-       pvt->has_fonts = TRUE;
+
+        terminal->pvt->unscaled_font_desc = desc /* adopted */;
+
+        vte_terminal_update_font(terminal);
 
         if (!same_desc)
                 g_object_notify(object, "font-desc");
+}
 
-       /* Set the drawing font. */
-       if (gtk_widget_get_realized (&terminal->widget)) {
-               vte_terminal_ensure_font (terminal);
-       }
+ /**
+ * vte_terminal_get_font:
+ * @terminal: a #VteTerminal
+ *
+ * Queries the terminal for information about the fonts which will be
+ * used to draw text in the terminal.
+ *
+ * Returns: (transfer none): a #PangoFontDescription describing the font the terminal is
+ *   currently using to render text
+ */
+const PangoFontDescription *
+vte_terminal_get_font(VteTerminal *terminal)
+{
+        g_return_val_if_fail(VTE_IS_TERMINAL(terminal), NULL);
 
-        g_object_thaw_notify(object);
+        return terminal->pvt->unscaled_font_desc;
 }
 
 /**
- * vte_terminal_set_font_from_string:
+ * vte_terminal_set_font_scale:
  * @terminal: a #VteTerminal
- * @name: (type utf8): a pango font description in string form
+ * @scale: the font scale
  *
- * A convenience function which converts @name into a #PangoFontDescription and
- * passes it to vte_terminal_set_font().
+ * Sets the terminal's font scale to @scale.
+ *
+ * Since: 0.30
  */
 void
-vte_terminal_set_font_from_string(VteTerminal *terminal,
-                                  const char *name)
+vte_terminal_set_font_scale(VteTerminal *terminal,
+                            gdouble scale)
 {
-       PangoFontDescription *font_desc = NULL;
-       g_return_if_fail(VTE_IS_TERMINAL(terminal));
-        g_return_if_fail(name != NULL);
+        g_return_if_fail(VTE_IS_TERMINAL(terminal));
+        g_return_if_fail(scale >= VTE_FONT_SCALE_MIN && scale <= VTE_FONT_SCALE_MAX);
 
-       if (name)
-                font_desc = pango_font_description_from_string(name);
-       vte_terminal_set_font(terminal, font_desc);
-       pango_font_description_free(font_desc);
+        terminal->pvt->font_scale = CLAMP(scale, VTE_FONT_SCALE_MIN, VTE_FONT_SCALE_MAX);
+        vte_terminal_update_font(terminal);
+
+        g_object_notify(G_OBJECT(terminal), "font-scale");
 }
 
 /**
- * vte_terminal_get_font:
+ * vte_terminal_get_font_scale:
  * @terminal: a #VteTerminal
  *
- * Queries the terminal for information about the fonts which will be
- * used to draw text in the terminal.
+ * Returns: the terminal's font scale
  *
- * Returns: (transfer none): a #PangoFontDescription describing the font the terminal is
- *   currently using to render text
+ * Since: 0.30
  */
-const PangoFontDescription *
-vte_terminal_get_font(VteTerminal *terminal)
+gdouble
+vte_terminal_get_font_scale(VteTerminal *terminal)
 {
-       g_return_val_if_fail(VTE_IS_TERMINAL(terminal), NULL);
-       return terminal->pvt->fontdesc;
+        g_return_val_if_fail(VTE_IS_TERMINAL(terminal), 1.);
+
+        return terminal->pvt->font_scale;
 }
 
 /* Read and refresh our perception of the size of the PTY. */
@@ -8216,6 +8257,8 @@ vte_terminal_init(VteTerminal *terminal)
         pvt->background_alpha = 1.;
 
        pvt->selection_block_mode = FALSE;
+        pvt->unscaled_font_desc = pvt->fontdesc = NULL;
+        pvt->font_scale = 1.;
        pvt->has_fonts = FALSE;
 
         pvt->alternate_screen_scroll = TRUE;
@@ -8528,6 +8571,7 @@ vte_terminal_finalize(GObject *object)
 {
        GtkWidget *widget = GTK_WIDGET (object);
        VteTerminal *terminal = VTE_TERMINAL (object);
+        VteTerminalPrivate *pvt = terminal->pvt;
        GtkClipboard *clipboard;
         GtkSettings *settings;
        struct vte_match_regex *regex;
@@ -8544,6 +8588,9 @@ vte_terminal_finalize(GObject *object)
        _vte_iso2022_state_free(terminal->pvt->iso2022);
 
        /* Free the font description. */
+        if (pvt->unscaled_font_desc != NULL) {
+                pango_font_description_free(pvt->unscaled_font_desc);
+        }
        if (terminal->pvt->fontdesc != NULL) {
                pango_font_description_free(terminal->pvt->fontdesc);
        }
@@ -10761,6 +10808,9 @@ vte_terminal_get_property (GObject *object,
                 case PROP_VISIBLE_BELL:
                         g_value_set_boolean (value, vte_terminal_get_visible_bell (terminal));
                         break;
+                case PROP_FONT_SCALE:
+                        g_value_set_double (value, vte_terminal_get_font_scale (terminal));
+                        break;
 
                default:
                        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
@@ -10847,6 +10897,9 @@ vte_terminal_set_property (GObject *object,
                 case PROP_VISIBLE_BELL:
                         vte_terminal_set_visible_bell (terminal, g_value_get_boolean (value));
                         break;
+                case PROP_FONT_SCALE:
+                        vte_terminal_set_font_scale (terminal, g_value_get_double (value));
+                        break;
 
                 /* Not writable */
                 case PROP_CURRENT_DIRECTORY_URI:
@@ -11619,7 +11672,23 @@ vte_terminal_class_init(VteTerminalClass *klass)
                  g_param_spec_string ("emulation", NULL, NULL,
                                       VTE_DEFAULT_EMULATION,
                                       G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
-     
+
+        /**
+         * VteTerminal:font-scale:
+         *
+         * The terminal's font scale.
+         *
+         * Since: 0.30
+         */
+        g_object_class_install_property
+                (gobject_class,
+                 PROP_AUDIBLE_BELL,
+                 g_param_spec_double ("font-scale", NULL, NULL,
+                                      VTE_FONT_SCALE_MIN,
+                                      VTE_FONT_SCALE_MAX,
+                                      1.,
+                                      G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
         /**
          * VteTerminal:encoding:
          *
diff --git a/src/vte.h b/src/vte.h
index 9075aa2..7bb4a75 100644
--- a/src/vte.h
+++ b/src/vte.h
@@ -91,6 +91,9 @@ struct _VteTerminalClass {
        void (*resize_window)(VteTerminal* terminal, guint width, guint height);
        void (*move_window)(VteTerminal* terminal, guint x, guint y);
 
+        /* FIXMEchpe: should these return gboolean and have defaul thandlers
+         * settings the "scale" property?
+         */
        void (*increase_font_size)(VteTerminal* terminal);
        void (*decrease_font_size)(VteTerminal* terminal);
 
@@ -220,6 +223,10 @@ void vte_terminal_select_none(VteTerminal *terminal);
 void vte_terminal_set_size(VteTerminal *terminal,
                           glong columns, glong rows);
 
+void vte_terminal_set_font_scale(VteTerminal *terminal,
+                                 gdouble scale);
+gdouble vte_terminal_get_font_scale(VteTerminal *terminal);
+
 /* Set various on-off settings. */
 void vte_terminal_set_audible_bell(VteTerminal *terminal, gboolean is_audible);
 gboolean vte_terminal_get_audible_bell(VteTerminal *terminal);
@@ -270,7 +277,6 @@ void vte_terminal_set_scrollback_lines(VteTerminal *terminal, glong lines);
 /* Set or retrieve the current font. */
 void vte_terminal_set_font(VteTerminal *terminal,
                           const PangoFontDescription *font_desc);
-void vte_terminal_set_font_from_string(VteTerminal *terminal, const char *name);
 const PangoFontDescription *vte_terminal_get_font(VteTerminal *terminal);
 void vte_terminal_set_allow_bold(VteTerminal *terminal, gboolean allow_bold);
 gboolean vte_terminal_get_allow_bold(VteTerminal *terminal);
diff --git a/src/vteapp.c b/src/vteapp.c
index f544573..254adfe 100644
--- a/src/vteapp.c
+++ b/src/vteapp.c
@@ -346,12 +346,11 @@ move_window(GtkWidget *widget, guint x, guint y, gpointer data)
 }
 
 static void
-adjust_font_size(GtkWidget *widget, gpointer data, gint howmuch)
+adjust_font_size(GtkWidget *widget, gpointer data, gdouble factor)
 {
        VteTerminal *terminal;
-       PangoFontDescription *desired;
+        gdouble scale;
         glong char_width, char_height;
-       gint newsize;
        gint columns, rows, owidth, oheight;
 
        /* Read the screen dimensions in cells. */
@@ -366,16 +365,8 @@ adjust_font_size(GtkWidget *widget, gpointer data, gint howmuch)
        owidth -= char_width * columns;
        oheight -= char_height * rows;
 
-       /* Calculate the new font size. */
-       desired = pango_font_description_copy(vte_terminal_get_font(terminal));
-       newsize = pango_font_description_get_size(desired) / PANGO_SCALE;
-       newsize += howmuch;
-       pango_font_description_set_size(desired,
-                                       CLAMP(newsize, 4, 144) * PANGO_SCALE);
-
-       /* Change the font, then resize the window so that we have the same
-        * number of rows and columns. */
-       vte_terminal_set_font(terminal, desired);
+       scale = vte_terminal_get_font_scale(terminal);
+        vte_terminal_set_font_scale(terminal, scale * factor);
 
         /* This above call will have changed the char size! */
         char_width = vte_terminal_get_char_width (terminal);
@@ -384,20 +375,18 @@ adjust_font_size(GtkWidget *widget, gpointer data, gint howmuch)
        gtk_window_resize(GTK_WINDOW(data),
                          columns * char_width + owidth,
                          rows * char_height + oheight);
-
-       pango_font_description_free(desired);
 }
 
 static void
 increase_font_size(GtkWidget *widget, gpointer data)
 {
-       adjust_font_size(widget, data, 1);
+       adjust_font_size(widget, data, 1.2);
 }
 
 static void
 decrease_font_size(GtkWidget *widget, gpointer data)
 {
-       adjust_font_size(widget, data, -1);
+       adjust_font_size(widget, data, 1. / 1.2);
 }
 
 static gboolean
@@ -907,7 +896,7 @@ main(int argc, char **argv)
        /* Create the terminal widget and add it to the scrolling shell. */
        widget = vteapp_terminal_new();
        terminal = VTE_TERMINAL (widget);
-       if (!dbuffer) {
+        if (!dbuffer) {
                gtk_widget_set_double_buffered(widget, dbuffer);
        }
        if (show_object_notifications)
@@ -1040,7 +1029,11 @@ main(int argc, char **argv)
 
        /* Set the default font. */
         if (font) {
-                vte_terminal_set_font_from_string(terminal, font);
+                PangoFontDescription *desc;
+
+                desc = pango_font_description_from_string(font);
+                vte_terminal_set_font(terminal, desc);
+                pango_font_description_free(desc);
         }
 
        /* Match "abcdefg". */