]> asedeno.scripts.mit.edu Git - PuTTY.git/blobdiff - unix/gtkwin.c
Widen the GTK askalg() message box.
[PuTTY.git] / unix / gtkwin.c
index b2a8aae1fc663cb96b289abd2bd1848f8b3b566b..872e6bb94f5f074e3f744028efe8f275bc8f2daf 100644 (file)
@@ -84,8 +84,33 @@ struct gui_data {
        *restartitem;
     GtkWidget *sessionsmenu;
 #ifndef NO_BACKING_PIXMAPS
+    /*
+     * Server-side pixmap which we use to cache the terminal window's
+     * contents. When we draw text in the terminal, we draw it to this
+     * pixmap first, and then blit from there to the actual window;
+     * this way, X expose events can be handled with an absolute
+     * minimum of network traffic, by just sending a command to
+     * re-blit an appropriate rectangle from this pixmap.
+     */
     GdkPixmap *pixmap;
 #endif
+#ifdef DRAW_TEXT_CAIRO
+    /*
+     * If we're drawing using Cairo, we cache the same image on the
+     * client side in a Cairo surface.
+     *
+     * In GTK2+Cairo, this happens _as well_ as having the server-side
+     * pixmap cache above; in GTK3+Cairo, server-side pixmaps are
+     * deprecated, so we _just_ have this client-side cache. In the
+     * latter case that means we have to transmit a big wodge of
+     * bitmap data over the X connection on every expose event; but
+     * GTK3 apparently deliberately provides no way to avoid that
+     * inefficiency, and at least this way we don't _also_ have to
+     * redo any font rendering just because the window was temporarily
+     * covered.
+     */
+    cairo_surface_t *surface;
+#endif
 #if GTK_CHECK_VERSION(2,0,0)
     GtkIMContext *imc;
 #endif
@@ -135,6 +160,9 @@ struct gui_data {
     int ngtkargs;
     guint32 input_event_time; /* Timestamp of the most recent input event. */
     int reconfiguring;
+#if GTK_CHECK_VERSION(3,4,0)
+    gdouble cumulative_scroll;
+#endif
     /* Cached things out of conf that we refer to a lot */
     int bold_style;
     int window_border;
@@ -515,17 +543,31 @@ gint configure_area(GtkWidget *widget, GdkEventConfigure *event, gpointer data)
        need_size = 1;
     }
 
+    {
+        int backing_w = w * inst->font_width + 2*inst->window_border;
+        int backing_h = h * inst->font_height + 2*inst->window_border;
+
 #ifndef NO_BACKING_PIXMAPS
-    if (inst->pixmap) {
-       gdk_pixmap_unref(inst->pixmap);
-       inst->pixmap = NULL;
-    }
+        if (inst->pixmap) {
+            gdk_pixmap_unref(inst->pixmap);
+            inst->pixmap = NULL;
+        }
 
-    inst->pixmap = gdk_pixmap_new(gtk_widget_get_window(widget),
-                                 (w * inst->font_width + 2*inst->window_border),
-                                 (h * inst->font_height + 2*inst->window_border), -1);
+        inst->pixmap = gdk_pixmap_new(gtk_widget_get_window(widget),
+                                      backing_w, backing_h, -1);
 #endif
 
+#ifdef DRAW_TEXT_CAIRO
+        if (inst->surface) {
+            cairo_surface_destroy(inst->surface);
+            inst->surface = NULL;
+        }
+
+        inst->surface = cairo_image_surface_create(CAIRO_FORMAT_RGB24,
+                                                   backing_w, backing_h);
+#endif
+    }
+
     draw_backing_rect(inst);
 
     if (need_size && inst->term) {
@@ -563,40 +605,21 @@ static gint draw_area(GtkWidget *widget, cairo_t *cr, gpointer data)
 {
     struct gui_data *inst = (struct gui_data *)data;
 
-    if (inst->term) {
-        struct draw_ctx adctx, *dctx = &adctx;
+    /*
+     * GTK3 window redraw: we always expect Cairo to be enabled, so
+     * that inst->surface exists, and pixmaps to be disabled, so that
+     * inst->pixmap does not exist. Hence, we just blit from
+     * inst->surface to the window.
+     */
+    if (inst->surface) {
         GdkRectangle dirtyrect;
 
-        dctx->inst = inst;
-        dctx->uctx.type = DRAWTYPE_CAIRO;
-        dctx->uctx.u.cairo.widget = widget;
-        dctx->uctx.u.cairo.cr = cr;
-        cairo_setup_dctx(dctx);
-
         gdk_cairo_get_clip_rectangle(cr, &dirtyrect);
 
-        /*
-         * As in window.c, we clear the 'immediately' flag in the
-         * term_paint() call if the terminal has an update pending, in
-         * case we're constrained within this event to only draw on
-         * the exposed rectangle of the window. (Because if the whole
-         * of a character cell needs a redraw due to a terminal
-         * contents change, the last thing we want is to give it a
-         * _partial_ redraw here due to system-imposed clipping, and
-         * then have the next main terminal update believe it's been
-         * redrawn in full.)
-         *
-         * I don't actually know if GTK draw events will constrain us
-         * in this way, but it's best to be careful...
-         */
-        term_paint(inst->term, dctx,
-                   (dirtyrect.x - inst->window_border) / inst->font_width,
-                   (dirtyrect.y - inst->window_border) / inst->font_height,
-                   (dirtyrect.x + dirtyrect.width -
-                    inst->window_border) / inst->font_width,
-                   (dirtyrect.y + dirtyrect.height -
-                    inst->window_border) / inst->font_height,
-                   !inst->term->window_update_pending);
+        cairo_set_source_surface(cr, inst->surface, 0, 0);
+        cairo_rectangle(cr, dirtyrect.x, dirtyrect.y,
+                        dirtyrect.width, dirtyrect.height);
+        cairo_fill(cr);
     }
 
     return TRUE;
@@ -608,8 +631,8 @@ gint expose_area(GtkWidget *widget, GdkEventExpose *event, gpointer data)
 
 #ifndef NO_BACKING_PIXMAPS
     /*
-     * Pass the exposed rectangle to terminal.c, which will call us
-     * back to do the actual painting.
+     * Draw to the exposed part of the window from the server-side
+     * backing pixmap.
      */
     if (inst->pixmap) {
        gdk_draw_pixmap(gtk_widget_get_window(widget),
@@ -621,17 +644,18 @@ gint expose_area(GtkWidget *widget, GdkEventExpose *event, gpointer data)
                        event->area.width, event->area.height);
     }
 #else
-    if (inst->term) {
-        Context ctx = get_ctx(inst);
-        term_paint(inst->term, ctx,
-                   (event->area.x - inst->window_border) / inst->font_width,
-                   (event->area.y - inst->window_border) / inst->font_height,
-                   (event->area.x + event->area.width -
-                    inst->window_border) / inst->font_width,
-                   (event->area.y + event->area.height -
-                    inst->window_border) / inst->font_height,
-                   !inst->term->window_update_pending);
-        free_ctx(ctx);
+    /*
+     * Failing that, draw from the client-side Cairo surface. (We
+     * should never be compiled in a context where we have _neither_
+     * inst->surface nor inst->pixmap.)
+     */
+    if (inst->surface) {
+        cairo_t *cr = gdk_cairo_create(gtk_widget_get_window(widget));
+        cairo_set_source_surface(cr, inst->surface, 0, 0);
+        cairo_rectangle(cr, event->area.x, event->area.y,
+                       event->area.width, event->area.height);
+        cairo_fill(cr);
+        cairo_destroy(cr);
     }
 #endif
 
@@ -642,6 +666,17 @@ gint expose_area(GtkWidget *widget, GdkEventExpose *event, gpointer data)
 #define KEY_PRESSED(k) \
     (inst->keystate[(k) / 32] & (1 << ((k) % 32)))
 
+#ifdef KEY_EVENT_DIAGNOSTICS
+char *dup_keyval_name(guint keyval)
+{
+    const char *name = gdk_keyval_name(keyval);
+    if (name)
+        return dupstr(name);
+    else
+        return dupprintf("UNKNOWN[%u]", (unsigned)keyval);
+}
+#endif
+
 gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
 {
     struct gui_data *inst = (struct gui_data *)data;
@@ -659,131 +694,82 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
     output_charset = CS_ISO8859_1;
 
 #ifdef KEY_EVENT_DIAGNOSTICS
-    /*
-     * Condition this mess in if you want to debug keyboard events as
-     * they come in to this function (e.g. because some particular
-     * port of GDK is producing an unexpected arrangement of
-     * modifiers).
-     */
-#define TRY(val, prefix, string)                                \
-    if ((val) == prefix ## string) printf("%s", #string); else
-#define GIVE_UP(val)                            \
-    printf("%d", (int)(val))
-#define TRY_MASK(val, prefix, string, suffix)           \
-        if ((val) & prefix ## string ## suffix) {       \
-            (val) &= ~ prefix ## string ## suffix;      \
-            printf("%s", #string);                      \
-            if (val) printf("|");                       \
+    {
+        char *type_string, *state_string, *keyval_string, *string_string;
+
+        type_string = (event->type == GDK_KEY_PRESS ? dupstr("PRESS") :
+                       event->type == GDK_KEY_RELEASE ? dupstr("RELEASE") :
+                       dupprintf("UNKNOWN[%d]", (int)event->type));
+
+        {
+            static const struct {
+                int mod_bit;
+                const char *name;
+            } mod_bits[] = {
+                {GDK_SHIFT_MASK, "SHIFT"},
+                {GDK_LOCK_MASK, "LOCK"},
+                {GDK_CONTROL_MASK, "CONTROL"},
+                {GDK_MOD1_MASK, "MOD1"},
+                {GDK_MOD2_MASK, "MOD2"},
+                {GDK_MOD3_MASK, "MOD3"},
+                {GDK_MOD4_MASK, "MOD4"},
+                {GDK_MOD5_MASK, "MOD5"},
+                {GDK_SUPER_MASK, "SUPER"},
+                {GDK_HYPER_MASK, "HYPER"},
+                {GDK_META_MASK, "META"},
+            };
+            int i;
+            int val = event->state;
+
+            state_string = dupstr("");
+
+            for (i = 0; i < lenof(mod_bits); i++) {
+                if (val & mod_bits[i].mod_bit) {
+                    char *old = state_string;
+                    state_string = dupcat(state_string,
+                                          state_string[0] ? "|" : "",
+                                          mod_bits[i].name,
+                                          (char *)NULL);
+                    sfree(old);
+
+                    val &= ~mod_bits[i].mod_bit;
+                }
+            }
+
+            if (val || !state_string[0]) {
+                char *old = state_string;
+                state_string = dupprintf("%s%s%d", state_string,
+                                         state_string[0] ? "|" : "", val);
+                sfree(old);
+            }
         }
-#define GIVE_UP_MASK(val)                               \
-        do                                              \
-        {                                               \
-            if ((val)) printf("%d", (int)(val));        \
-        } while (0)
 
-    printf("key_event: type=");
-    TRY(event->type, GDK_KEY_, PRESS)
-    TRY(event->type, GDK_KEY_, RELEASE)
-    GIVE_UP(event->type);
-    printf(" keyval=");
-    TRY(event->keyval, GDK_KEY_, Alt_L)
-    TRY(event->keyval, GDK_KEY_, Alt_R)
-    TRY(event->keyval, GDK_KEY_, BackSpace)
-    TRY(event->keyval, GDK_KEY_, Begin)
-    TRY(event->keyval, GDK_KEY_, Break)
-    TRY(event->keyval, GDK_KEY_, Delete)
-    TRY(event->keyval, GDK_KEY_, Down)
-    TRY(event->keyval, GDK_KEY_, End)
-    TRY(event->keyval, GDK_KEY_, Escape)
-    TRY(event->keyval, GDK_KEY_, F10)
-    TRY(event->keyval, GDK_KEY_, F11)
-    TRY(event->keyval, GDK_KEY_, F12)
-    TRY(event->keyval, GDK_KEY_, F13)
-    TRY(event->keyval, GDK_KEY_, F14)
-    TRY(event->keyval, GDK_KEY_, F15)
-    TRY(event->keyval, GDK_KEY_, F16)
-    TRY(event->keyval, GDK_KEY_, F17)
-    TRY(event->keyval, GDK_KEY_, F18)
-    TRY(event->keyval, GDK_KEY_, F19)
-    TRY(event->keyval, GDK_KEY_, F1)
-    TRY(event->keyval, GDK_KEY_, F20)
-    TRY(event->keyval, GDK_KEY_, F2)
-    TRY(event->keyval, GDK_KEY_, F3)
-    TRY(event->keyval, GDK_KEY_, F4)
-    TRY(event->keyval, GDK_KEY_, F5)
-    TRY(event->keyval, GDK_KEY_, F6)
-    TRY(event->keyval, GDK_KEY_, F7)
-    TRY(event->keyval, GDK_KEY_, F8)
-    TRY(event->keyval, GDK_KEY_, F9)
-    TRY(event->keyval, GDK_KEY_, Home)
-    TRY(event->keyval, GDK_KEY_, Insert)
-    TRY(event->keyval, GDK_KEY_, ISO_Left_Tab)
-    TRY(event->keyval, GDK_KEY_, KP_0)
-    TRY(event->keyval, GDK_KEY_, KP_1)
-    TRY(event->keyval, GDK_KEY_, KP_2)
-    TRY(event->keyval, GDK_KEY_, KP_3)
-    TRY(event->keyval, GDK_KEY_, KP_4)
-    TRY(event->keyval, GDK_KEY_, KP_5)
-    TRY(event->keyval, GDK_KEY_, KP_6)
-    TRY(event->keyval, GDK_KEY_, KP_7)
-    TRY(event->keyval, GDK_KEY_, KP_8)
-    TRY(event->keyval, GDK_KEY_, KP_9)
-    TRY(event->keyval, GDK_KEY_, KP_Add)
-    TRY(event->keyval, GDK_KEY_, KP_Begin)
-    TRY(event->keyval, GDK_KEY_, KP_Decimal)
-    TRY(event->keyval, GDK_KEY_, KP_Delete)
-    TRY(event->keyval, GDK_KEY_, KP_Divide)
-    TRY(event->keyval, GDK_KEY_, KP_Down)
-    TRY(event->keyval, GDK_KEY_, KP_End)
-    TRY(event->keyval, GDK_KEY_, KP_Enter)
-    TRY(event->keyval, GDK_KEY_, KP_Home)
-    TRY(event->keyval, GDK_KEY_, KP_Insert)
-    TRY(event->keyval, GDK_KEY_, KP_Left)
-    TRY(event->keyval, GDK_KEY_, KP_Multiply)
-    TRY(event->keyval, GDK_KEY_, KP_Page_Down)
-    TRY(event->keyval, GDK_KEY_, KP_Page_Up)
-    TRY(event->keyval, GDK_KEY_, KP_Right)
-    TRY(event->keyval, GDK_KEY_, KP_Subtract)
-    TRY(event->keyval, GDK_KEY_, KP_Up)
-    TRY(event->keyval, GDK_KEY_, Left)
-    TRY(event->keyval, GDK_KEY_, Meta_L)
-    TRY(event->keyval, GDK_KEY_, Meta_R)
-    TRY(event->keyval, GDK_KEY_, Num_Lock)
-    TRY(event->keyval, GDK_KEY_, Page_Down)
-    TRY(event->keyval, GDK_KEY_, Page_Up)
-    TRY(event->keyval, GDK_KEY_, Return)
-    TRY(event->keyval, GDK_KEY_, Right)
-    TRY(event->keyval, GDK_KEY_, Tab)
-    TRY(event->keyval, GDK_KEY_, Up)
-    TRY(event->keyval, GDK_KEY_, Shift_L)
-    TRY(event->keyval, GDK_KEY_, Shift_R)
-    TRY(event->keyval, GDK_KEY_, Control_L)
-    TRY(event->keyval, GDK_KEY_, Control_R)
-    TRY(event->keyval, GDK_KEY_, Caps_Lock)
-    TRY(event->keyval, GDK_KEY_, Shift_Lock)
-    TRY(event->keyval, GDK_KEY_, Super_L)
-    TRY(event->keyval, GDK_KEY_, Super_R)
-    TRY(event->keyval, GDK_KEY_, Hyper_L)
-    TRY(event->keyval, GDK_KEY_, Hyper_R)
-    GIVE_UP(event->keyval);
-    printf(" state=");
-    {
-        int val = event->state;
-        TRY_MASK(val, GDK_, SHIFT, _MASK)
-        TRY_MASK(val, GDK_, LOCK, _MASK)
-        TRY_MASK(val, GDK_, CONTROL, _MASK)
-        TRY_MASK(val, GDK_, MOD1, _MASK)
-        TRY_MASK(val, GDK_, MOD2, _MASK)
-        TRY_MASK(val, GDK_, MOD3, _MASK)
-        TRY_MASK(val, GDK_, MOD4, _MASK)
-        TRY_MASK(val, GDK_, MOD5, _MASK)
-        TRY_MASK(val, GDK_, SUPER, _MASK)
-        TRY_MASK(val, GDK_, HYPER, _MASK)
-        TRY_MASK(val, GDK_, META, _MASK)
-        GIVE_UP_MASK(val);
+        keyval_string = dup_keyval_name(event->keyval);
+
+        string_string = dupstr("");
+        {
+            int i;
+            for (i = 0; event->string[i]; i++) {
+                char *old = string_string;
+                string_string = dupprintf("%s%s%02x", string_string,
+                                          string_string[0] ? " " : "",
+                                          (unsigned)event->string[i] & 0xFF);
+                sfree(old);
+            }
+        }
+
+        debug(("key_event: type=%s keyval=%s state=%s "
+               "hardware_keycode=%d is_modifier=%s string=[%s]\n",
+               type_string, keyval_string, state_string,
+               (int)event->hardware_keycode,
+               event->is_modifier ? "TRUE" : "FALSE",
+               string_string));
+
+        sfree(type_string);
+        sfree(state_string);
+        sfree(keyval_string);
+        sfree(string_string);
     }
-    printf(" hardware_keycode=%d is_modifier=%s\n",
-           (int)event->hardware_keycode, event->is_modifier ? "TRUE" : "FALSE");
 #endif /* KEY_EVENT_DIAGNOSTICS */
 
     /*
@@ -802,8 +788,9 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
              event->keyval == GDK_KEY_Alt_L ||
              event->keyval == GDK_KEY_Alt_R) &&
             inst->alt_keycode >= 0 && inst->alt_digits > 1) {
-#ifdef KEY_DEBUGGING
-            printf("Alt key up, keycode = %d\n", inst->alt_keycode);
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - modifier release terminates Alt+numberpad input, "
+                   "keycode = %d\n", inst->alt_keycode));
 #endif
             /*
              * FIXME: we might usefully try to do something clever here
@@ -815,27 +802,23 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
             goto done;
         }
 #if GTK_CHECK_VERSION(2,0,0)
-        if (gtk_im_context_filter_keypress(inst->imc, event))
+#ifdef KEY_EVENT_DIAGNOSTICS
+        debug((" - key release, passing to IM\n"));
+#endif
+        if (gtk_im_context_filter_keypress(inst->imc, event)) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - key release accepted by IM\n"));
+#endif
             return TRUE;
+        } else {
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - key release not accepted by IM\n"));
+#endif
+        }
 #endif
     }
 
     if (event->type == GDK_KEY_PRESS) {
-#ifdef KEY_DEBUGGING
-       {
-           int i;
-           printf("keypress: keyval = %04x, state = %08x; string =",
-                  event->keyval, event->state);
-           for (i = 0; event->string[i]; i++)
-               printf(" %02x", (unsigned char) event->string[i]);
-           printf("\n");
-       }
-#endif
-
-       /*
-        * NYI: Compose key (!!! requires Unicode faff before even trying)
-        */
-
        /*
         * If Alt has just been pressed, we start potentially
         * accumulating an Alt+numberpad code. We do this by
@@ -845,6 +828,10 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
             event->keyval == GDK_KEY_Meta_R ||
              event->keyval == GDK_KEY_Alt_L ||
              event->keyval == GDK_KEY_Alt_R)) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - modifier press potentially begins Alt+numberpad "
+                   "input\n"));
+#endif
            inst->alt_keycode = -1;
             inst->alt_digits = 0;
            goto done;                 /* this generates nothing else */
@@ -873,17 +860,17 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
            if (digit < 0)
                inst->alt_keycode = -2;   /* it's invalid */
            else {
-#ifdef KEY_DEBUGGING
-               printf("Adding digit %d to keycode %d", digit,
-                      inst->alt_keycode);
+#ifdef KEY_EVENT_DIAGNOSTICS
+                int old_keycode = inst->alt_keycode;
 #endif
                if (inst->alt_keycode == -1)
                    inst->alt_keycode = digit;   /* one-digit code */
                else
                    inst->alt_keycode = inst->alt_keycode * 10 + digit;
                 inst->alt_digits++;
-#ifdef KEY_DEBUGGING
-               printf(" gives new code %d\n", inst->alt_keycode);
+#ifdef KEY_EVENT_DIAGNOSTICS
+                debug((" - Alt+numberpad digit %d added to keycode %d"
+                       " gives %d\n", digit, old_keycode, inst->alt_keycode));
 #endif
                /* Having used this digit, we now do nothing more with it. */
                goto done;
@@ -896,21 +883,33 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
         */
        if (event->keyval == GDK_KEY_Page_Up &&
             (event->state & GDK_SHIFT_MASK)) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - Shift-PgUp scroll\n"));
+#endif
            term_scroll(inst->term, 0, -inst->height/2);
            return TRUE;
        }
        if (event->keyval == GDK_KEY_Page_Up &&
             (event->state & GDK_CONTROL_MASK)) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - Ctrl-PgUp scroll\n"));
+#endif
            term_scroll(inst->term, 0, -1);
            return TRUE;
        }
        if (event->keyval == GDK_KEY_Page_Down &&
             (event->state & GDK_SHIFT_MASK)) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - Shift-PgDn scroll\n"));
+#endif
            term_scroll(inst->term, 0, +inst->height/2);
            return TRUE;
        }
        if (event->keyval == GDK_KEY_Page_Down &&
             (event->state & GDK_CONTROL_MASK)) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - Ctrl-PgDn scroll\n"));
+#endif
            term_scroll(inst->term, 0, +1);
            return TRUE;
        }
@@ -920,6 +919,9 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
         */
        if (event->keyval == GDK_KEY_Insert &&
             (event->state & GDK_SHIFT_MASK)) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - Shift-Insert paste\n"));
+#endif
            request_paste(inst);
            return TRUE;
        }
@@ -943,7 +945,7 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
         */
        output_charset = CS_ISO8859_1;
        strncpy(output+1, event->string, lenof(output)-1);
-#else
+#else /* !GTK_CHECK_VERSION(2,0,0) */
         /*
          * Most things can now be passed to
          * gtk_im_context_filter_keypress without breaking anything
@@ -1003,6 +1005,8 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
                     event->keyval == GDK_KEY_KP_Page_Up)) {
             /* nethack mode; do nothing */
         } else {
+            int try_filter = TRUE;
+
 #ifdef META_MANUAL_MASK
             if (event->state & META_MANUAL_MASK & inst->meta_mod_mask) {
                 /*
@@ -1012,10 +1016,29 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
                  * (it will eat the keystroke and turn it into
                  * something not what we wanted).
                  */
-            } else
+#ifdef KEY_EVENT_DIAGNOSTICS
+                debug((" - Meta modifier requiring manual intervention, "
+                       "suppressing IM filtering\n"));
+#endif
+                try_filter = FALSE;
+            }
+#endif
+
+            if (try_filter) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+                debug((" - general key press, passing to IM\n"));
+#endif
+                if (gtk_im_context_filter_keypress(inst->imc, event)) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+                    debug((" - key press accepted by IM\n"));
 #endif
-                if (gtk_im_context_filter_keypress(inst->imc, event))
                     return TRUE;
+                } else {
+#ifdef KEY_EVENT_DIAGNOSTICS
+                    debug((" - key press not accepted by IM\n"));
+#endif
+                }
+            }
         }
 
        /*
@@ -1041,17 +1064,58 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
                            event->string, strlen(event->string),
                            widedata, lenof(widedata)-1);
 
+#ifdef KEY_EVENT_DIAGNOSTICS
+            {
+                char *string_string = dupstr("");
+                int i;
+
+                for (i = 0; i < wlen; i++) {
+                    char *old = string_string;
+                    string_string = dupprintf("%s%s%04x", string_string,
+                                              string_string[0] ? " " : "",
+                                              (unsigned)widedata[i]);
+                    sfree(old);
+                }
+                debug((" - string translated into Unicode = [%s]\n",
+                       string_string));
+                sfree(string_string);
+            }
+#endif
+
            wp = widedata;
            ulen = charset_from_unicode(&wp, &wlen, output+1, lenof(output)-2,
                                        CS_UTF8, NULL, NULL, 0);
+
+#ifdef KEY_EVENT_DIAGNOSTICS
+            {
+                char *string_string = dupstr("");
+                int i;
+
+                for (i = 0; i < ulen; i++) {
+                    char *old = string_string;
+                    string_string = dupprintf("%s%s%02x", string_string,
+                                              string_string[0] ? " " : "",
+                                              (unsigned)output[i+1] & 0xFF);
+                    sfree(old);
+                }
+                debug((" - string translated into UTF-8 = [%s]\n",
+                       string_string));
+                sfree(string_string);
+            }
+#endif
+
            output[1+ulen] = '\0';
        }
-#endif
+#endif /* !GTK_CHECK_VERSION(2,0,0) */
 
        if (!output[1] &&
            (ucsval = keysym_to_unicode(event->keyval)) >= 0) {
            ucsoutput[0] = '\033';
            ucsoutput[1] = ucsval;
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - keysym_to_unicode gave %04x\n",
+                   (unsigned)ucsoutput[1]));
+#endif
            use_ucsoutput = TRUE;
            end = 2;
        } else {
@@ -1083,6 +1147,15 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
                      0, &new_keyval, NULL, NULL, &consumed)) {
                     ucsoutput[0] = '\033';
                     ucsoutput[1] = gdk_keyval_to_unicode(new_keyval);
+#ifdef KEY_EVENT_DIAGNOSTICS
+                    {
+                        char *keyval_name = dup_keyval_name(new_keyval);
+                        debug((" - retranslation for manual Meta: "
+                               "new keyval = %s, Unicode = %04x\n",
+                               keyval_name, (unsigned)ucsoutput[1]));
+                        sfree(keyval_name);
+                    }
+#endif
                     use_ucsoutput = TRUE;
                     end = 2;
                 }
@@ -1094,6 +1167,9 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
        /* Control-` is the same as Control-\ (unless gtk has a better idea) */
        if (!output[1] && event->keyval == '`' &&
            (event->state & GDK_CONTROL_MASK)) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - Ctrl-` special case, translating as 1c\n"));
+#endif
            output[1] = '\x1C';
            use_ucsoutput = FALSE;
            end = 2;
@@ -1106,6 +1182,10 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
          * The translations below are in line with X11 policy as far
          * as I know. */
         if ((event->state & GDK_CONTROL_MASK) && end == 2) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+            int orig = output[1];
+#endif
+
             if (output[1] >= '3' && output[1] <= '7') {
                 /* ^3,...,^7 map to 0x1B,...,0x1F */
                 output[1] += '\x1B' - '3';
@@ -1124,11 +1204,22 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
                 output[1] &= 0x1F;
             }
             /* Anything else, e.g. '0', is unchanged. */
+
+#ifdef KEY_EVENT_DIAGNOSTICS
+            if (orig == output[1])
+                debug((" - manual Ctrl key handling did nothing\n"));
+            else
+                debug((" - manual Ctrl key handling: %02x -> %02x\n",
+                       (unsigned)orig, (unsigned)output[1]));
+#endif
         }
 
        /* Control-Break sends a Break special to the backend */
        if (event->keyval == GDK_KEY_Break &&
            (event->state & GDK_CONTROL_MASK)) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - Ctrl-Break special case, sending TS_BRK\n"));
+#endif
            if (inst->back)
                inst->back->special(inst->backhandle, TS_BRK);
            return TRUE;
@@ -1137,6 +1228,9 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
        /* We handle Return ourselves, because it needs to be flagged as
         * special to ldisc. */
        if (event->keyval == GDK_KEY_Return) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - Return special case, translating as 0d + special\n"));
+#endif
            output[1] = '\015';
            use_ucsoutput = FALSE;
            end = 2;
@@ -1149,6 +1243,9 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
             event->keyval == '@') &&
            (event->state & (GDK_SHIFT_MASK |
                             GDK_CONTROL_MASK)) == GDK_CONTROL_MASK) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - Ctrl-{space,2,@} special case, translating as 00\n"));
+#endif
            output[1] = '\0';
            use_ucsoutput = FALSE;
            end = 2;
@@ -1158,6 +1255,9 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
        if (!output[1] && event->keyval == ' ' &&
            (event->state & (GDK_SHIFT_MASK | GDK_CONTROL_MASK)) ==
            (GDK_SHIFT_MASK | GDK_CONTROL_MASK)) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - Ctrl-Shift-space special case, translating as 00a0\n"));
+#endif
            output[1] = '\240';
            output_charset = CS_ISO8859_1;
            use_ucsoutput = FALSE;
@@ -1169,6 +1269,10 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
            !(event->state & GDK_SHIFT_MASK)) {
            output[1] = conf_get_int(inst->conf, CONF_bksp_is_delete) ?
                '\x7F' : '\x08';
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - Backspace, translating as %02x\n",
+                   (unsigned)output[1]));
+#endif
            use_ucsoutput = FALSE;
            end = 2;
            special = TRUE;
@@ -1178,6 +1282,10 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
            (event->state & GDK_SHIFT_MASK)) {
            output[1] = conf_get_int(inst->conf, CONF_bksp_is_delete) ?
                '\x08' : '\x7F';
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - Shift-Backspace, translating as %02x\n",
+                   (unsigned)output[1]));
+#endif
            use_ucsoutput = FALSE;
            end = 2;
            special = TRUE;
@@ -1187,6 +1295,9 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
        if (event->keyval == GDK_KEY_ISO_Left_Tab ||
            (event->keyval == GDK_KEY_Tab &&
              (event->state & GDK_SHIFT_MASK))) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - Shift-Tab, translating as ESC [ Z\n"));
+#endif
            end = 1 + sprintf(output+1, "\033[Z");
            use_ucsoutput = FALSE;
        }
@@ -1194,6 +1305,9 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
         * (Curiously, at least one version of the MacOS 10.5 X server
         * doesn't translate Tab for us. */
        if (event->keyval == GDK_KEY_Tab && end <= 1) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+            debug((" - Tab, translating as 09\n"));
+#endif
            output[1] = '\t';
            end = 2;
        }
@@ -1231,6 +1345,9 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
                    output[1] = keys[1];
                else
                    output[1] = keys[0];
+#ifdef KEY_EVENT_DIAGNOSTICS
+                debug((" - Nethack-mode key"));
+#endif
                use_ucsoutput = FALSE;
                goto done;
            }
@@ -1286,6 +1403,9 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
                } else
                    end = 1 + sprintf(output+1, "\033O%c", xkey);
                use_ucsoutput = FALSE;
+#ifdef KEY_EVENT_DIAGNOSTICS
+                debug((" - Application keypad mode key"));
+#endif
                goto done;
            }
        }
@@ -1390,6 +1510,9 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
 
            if (inst->term->vt52_mode && code > 0 && code <= 6) {
                end = 1 + sprintf(output+1, "\x1B%c", " HLMEIG"[code]);
+#ifdef KEY_EVENT_DIAGNOSTICS
+                debug((" - VT52 mode small keypad key"));
+#endif
                use_ucsoutput = FALSE;
                goto done;
            }
@@ -1415,6 +1538,9 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
                if (event->state & GDK_SHIFT_MASK) index += 12;
                if (event->state & GDK_CONTROL_MASK) index += 24;
                end = 1 + sprintf(output+1, "\x1B[%c", codes[index]);
+#ifdef KEY_EVENT_DIAGNOSTICS
+                debug((" - SCO mode function key"));
+#endif
                use_ucsoutput = FALSE;
                goto done;
            }
@@ -1427,6 +1553,9 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
                } else {
                    end = 1 + sprintf(output+1, "\x1B[%c", codes[code-1]);
                }
+#ifdef KEY_EVENT_DIAGNOSTICS
+                debug((" - SCO mode small keypad key"));
+#endif
                use_ucsoutput = FALSE;
                goto done;
            }
@@ -1437,35 +1566,59 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
                    offt++;
                if (code > 21)
                    offt++;
-               if (inst->term->vt52_mode)
+               if (inst->term->vt52_mode) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+                    debug((" - VT52 mode function key"));
+#endif
                    end = 1 + sprintf(output+1,
                                      "\x1B%c", code + 'P' - 11 - offt);
-               else
+                } else {
+#ifdef KEY_EVENT_DIAGNOSTICS
+                    debug((" - VT100+ mode function key"));
+#endif
                    end = 1 + sprintf(output+1,
                                      "\x1BO%c", code + 'P' - 11 - offt);
+                }
                use_ucsoutput = FALSE;
                goto done;
            }
            if (funky_type == FUNKY_LINUX && code >= 11 && code <= 15) {
                end = 1 + sprintf(output+1, "\x1B[[%c", code + 'A' - 11);
+#ifdef KEY_EVENT_DIAGNOSTICS
+                debug((" - Linux mode F1-F5 function key"));
+#endif
                use_ucsoutput = FALSE;
                goto done;
            }
            if (funky_type == FUNKY_XTERM && code >= 11 && code <= 14) {
-               if (inst->term->vt52_mode)
+               if (inst->term->vt52_mode) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+                    debug((" - VT52 mode (overriding xterm) F1-F4 function"
+                           " key"));
+#endif
                    end = 1 + sprintf(output+1, "\x1B%c", code + 'P' - 11);
-               else
+                } else {
+#ifdef KEY_EVENT_DIAGNOSTICS
+                    debug((" - xterm mode F1-F4 function key"));
+#endif
                    end = 1 + sprintf(output+1, "\x1BO%c", code + 'P' - 11);
+                }
                use_ucsoutput = FALSE;
                goto done;
            }
            if ((code == 1 || code == 4) &&
                conf_get_int(inst->conf, CONF_rxvt_homeend)) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+                debug((" - rxvt style Home/End"));
+#endif
                end = 1 + sprintf(output+1, code == 1 ? "\x1B[H" : "\x1BOw");
                use_ucsoutput = FALSE;
                goto done;
            }
            if (code) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+                debug((" - ordinary function key encoding"));
+#endif
                end = 1 + sprintf(output+1, "\x1B[%d~", code);
                use_ucsoutput = FALSE;
                goto done;
@@ -1491,6 +1644,9 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
            if (xkey) {
                end = 1 + format_arrow_key(output+1, inst->term, xkey,
                                           event->state & GDK_CONTROL_MASK);
+#ifdef KEY_EVENT_DIAGNOSTICS
+                debug((" - arrow key"));
+#endif
                use_ucsoutput = FALSE;
                goto done;
            }
@@ -1501,15 +1657,22 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
     done:
 
     if (end-start > 0) {
-#ifdef KEY_DEBUGGING
-       int i;
-       printf("generating sequence:");
-       for (i = start; i < end; i++)
-           printf(" %02x", (unsigned char) output[i]);
-       printf("\n");
-#endif
-
        if (special) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+            char *string_string = dupstr("");
+            int i;
+
+            for (i = start; i < end; i++) {
+                char *old = string_string;
+                string_string = dupprintf("%s%s%02x", string_string,
+                                          string_string[0] ? " " : "",
+                                          (unsigned)output[i] & 0xFF);
+                sfree(old);
+            }
+            debug((" - final output, special, generic encoding = [%s]\n",
+                   charset_to_localenc(output_charset), string_string));
+            sfree(string_string);
+#endif
            /*
             * For special control characters, the character set
             * should never matter.
@@ -1519,10 +1682,41 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
                ldisc_send(inst->ldisc, output+start, -2, 1);
        } else if (!inst->direct_to_font) {
            if (!use_ucsoutput) {
+#ifdef KEY_EVENT_DIAGNOSTICS
+                char *string_string = dupstr("");
+                int i;
+
+                for (i = start; i < end; i++) {
+                    char *old = string_string;
+                    string_string = dupprintf("%s%s%02x", string_string,
+                                              string_string[0] ? " " : "",
+                                              (unsigned)output[i] & 0xFF);
+                    sfree(old);
+                }
+                debug((" - final output in %s = [%s]\n",
+                       charset_to_localenc(output_charset), string_string));
+                sfree(string_string);
+#endif
                if (inst->ldisc)
                    lpage_send(inst->ldisc, output_charset, output+start,
                               end-start, 1);
            } else {
+#ifdef KEY_EVENT_DIAGNOSTICS
+                char *string_string = dupstr("");
+                int i;
+
+                for (i = start; i < end; i++) {
+                    char *old = string_string;
+                    string_string = dupprintf("%s%s%04x", string_string,
+                                              string_string[0] ? " " : "",
+                                              (unsigned)ucsoutput[i]);
+                    sfree(old);
+                }
+                debug((" - final output in Unicode = [%s]\n",
+                       string_string));
+                sfree(string_string);
+#endif
+
                /*
                 * We generated our own Unicode key data from the
                 * keysym, so use that instead.
@@ -1535,6 +1729,21 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
             * In direct-to-font mode, we just send the string
             * exactly as we received it.
             */
+#ifdef KEY_EVENT_DIAGNOSTICS
+            char *string_string = dupstr("");
+            int i;
+
+            for (i = start; i < end; i++) {
+                char *old = string_string;
+                string_string = dupprintf("%s%s%02x", string_string,
+                                          string_string[0] ? " " : "",
+                                          (unsigned)output[i] & 0xFF);
+                sfree(old);
+            }
+            debug((" - final output in direct-to-font encoding = [%s]\n",
+                   string_string));
+            sfree(string_string);
+#endif
            if (inst->ldisc)
                ldisc_send(inst->ldisc, output+start, end-start, 1);
        }
@@ -1550,6 +1759,22 @@ gint key_event(GtkWidget *widget, GdkEventKey *event, gpointer data)
 void input_method_commit_event(GtkIMContext *imc, gchar *str, gpointer data)
 {
     struct gui_data *inst = (struct gui_data *)data;
+
+#ifdef KEY_EVENT_DIAGNOSTICS
+    char *string_string = dupstr("");
+    int i;
+
+    for (i = 0; str[i]; i++) {
+        char *old = string_string;
+        string_string = dupprintf("%s%s%02x", string_string,
+                                  string_string[0] ? " " : "",
+                                  (unsigned)str[i] & 0xFF);
+        sfree(old);
+    }
+    debug((" - IM commit event in UTF-8 = [%s]\n", string_string));
+    sfree(string_string);
+#endif
+
     if (inst->ldisc)
         lpage_send(inst->ldisc, CS_UTF8, str, strlen(str), 1);
     show_mouseptr(inst, 0);
@@ -1557,6 +1782,61 @@ void input_method_commit_event(GtkIMContext *imc, gchar *str, gpointer data)
 }
 #endif
 
+#define SCROLL_INCREMENT_LINES 5
+
+#if GTK_CHECK_VERSION(3,4,0)
+gboolean scroll_internal(struct gui_data *inst, gdouble delta, guint state,
+                        gdouble ex, gdouble ey)
+{
+    int shift, ctrl, alt, x, y, raw_mouse_mode;
+
+    show_mouseptr(inst, 1);
+
+    shift = state & GDK_SHIFT_MASK;
+    ctrl = state & GDK_CONTROL_MASK;
+    alt = state & inst->meta_mod_mask;
+
+    x = (ex - inst->window_border) / inst->font_width;
+    y = (ey - inst->window_border) / inst->font_height;
+
+    raw_mouse_mode =
+        send_raw_mouse && !(shift && conf_get_int(inst->conf,
+                                                  CONF_mouse_override));
+
+    inst->cumulative_scroll += delta * SCROLL_INCREMENT_LINES;
+
+    if (!raw_mouse_mode) {
+        int scroll_lines = (int)inst->cumulative_scroll; /* rounds toward 0 */
+        if (scroll_lines) {
+            term_scroll(inst->term, 0, scroll_lines);
+            inst->cumulative_scroll -= scroll_lines;
+        }
+        return TRUE;
+    } else {
+        int scroll_events = (int)(inst->cumulative_scroll /
+                                  SCROLL_INCREMENT_LINES);
+        if (scroll_events) {
+            int button;
+
+            inst->cumulative_scroll -= scroll_events * SCROLL_INCREMENT_LINES;
+
+            if (scroll_events > 0) {
+                button = MBT_WHEEL_DOWN;
+            } else {
+                button = MBT_WHEEL_UP;
+                scroll_events = -scroll_events;
+            }
+
+            while (scroll_events-- > 0) {
+                term_mouse(inst->term, button, translate_button(button),
+                           MA_CLICK, x, y, shift, ctrl, alt);
+            }
+        }
+        return TRUE;
+    }
+}
+#endif
+
 gboolean button_internal(struct gui_data *inst, guint32 timestamp,
                         GdkEventType type, guint ebutton, guint state,
                         gdouble ex, gdouble ey)
@@ -1578,11 +1858,11 @@ gboolean button_internal(struct gui_data *inst, guint32 timestamp,
 
     if (!raw_mouse_mode) {
         if (ebutton == 4 && type == GDK_BUTTON_PRESS) {
-            term_scroll(inst->term, 0, -5);
+            term_scroll(inst->term, 0, -SCROLL_INCREMENT_LINES);
             return TRUE;
         }
         if (ebutton == 5 && type == GDK_BUTTON_PRESS) {
-            term_scroll(inst->term, 0, +5);
+            term_scroll(inst->term, 0, +SCROLL_INCREMENT_LINES);
             return TRUE;
         }
     }
@@ -1642,8 +1922,15 @@ gboolean button_event(GtkWidget *widget, GdkEventButton *event, gpointer data)
 gboolean scroll_event(GtkWidget *widget, GdkEventScroll *event, gpointer data)
 {
     struct gui_data *inst = (struct gui_data *)data;
-    guint button;
 
+#if GTK_CHECK_VERSION(3,4,0)
+    gdouble dx, dy;
+    if (gdk_event_get_scroll_deltas((GdkEvent *)event, &dx, &dy)) {
+        return scroll_internal(inst, dy, event->state, event->x, event->y);
+    } else
+        return FALSE;
+#else
+    guint button;
     if (event->direction == GDK_SCROLL_UP)
        button = 4;
     else if (event->direction == GDK_SCROLL_DOWN)
@@ -1653,6 +1940,7 @@ gboolean scroll_event(GtkWidget *widget, GdkEventScroll *event, gpointer data)
 
     return button_internal(inst, event->time, GDK_BUTTON_PRESS,
                           button, event->state, event->x, event->y);
+#endif
 }
 #endif
 
@@ -2803,11 +3091,8 @@ void do_beep(void *frontend, int mode)
 int char_width(Context ctx, int uc)
 {
     /*
-     * Under X, any fixed-width font really _is_ fixed-width.
-     * Double-width characters will be dealt with using a separate
-     * font. For the moment we can simply return 1.
-     * 
-     * FIXME: but is that also true of Pango?
+     * In this front end, double-width characters are handled using a
+     * separate font, so this can safely just return 1 always.
      */
     return 1;
 }
@@ -2816,30 +3101,28 @@ Context get_ctx(void *frontend)
 {
     struct gui_data *inst = (struct gui_data *)frontend;
     struct draw_ctx *dctx;
-    GdkWindow *target;
 
     if (!gtk_widget_get_window(inst->area))
        return NULL;
 
-#ifndef NO_BACKING_PIXMAPS
-    target = inst->pixmap;
-#else
-    target = gtk_widget_get_window(inst->area);
-#endif
-
     dctx = snew(struct draw_ctx);
     dctx->inst = inst;
     dctx->uctx.type = inst->drawtype;
 #ifdef DRAW_TEXT_GDK
     if (dctx->uctx.type == DRAWTYPE_GDK) {
-        dctx->uctx.u.gdk.target = target;
+        /* If we're doing GDK-based drawing, then we also expect
+         * inst->pixmap to exist. */
+        dctx->uctx.u.gdk.target = inst->pixmap;
         dctx->uctx.u.gdk.gc = gdk_gc_new(gtk_widget_get_window(inst->area));
     }
 #endif
 #ifdef DRAW_TEXT_CAIRO
     if (dctx->uctx.type == DRAWTYPE_CAIRO) {
         dctx->uctx.u.cairo.widget = GTK_WIDGET(inst->area);
-        dctx->uctx.u.cairo.cr = gdk_cairo_create(target);
+        /* If we're doing Cairo drawing, we expect inst->surface to
+         * exist, and we draw to that first, regardless of whether we
+         * subsequently copy the results to inst->pixmap. */
+        dctx->uctx.u.cairo.cr = cairo_create(inst->surface);
         cairo_setup_dctx(dctx);
     }
 #endif
@@ -2866,23 +3149,31 @@ void free_ctx(Context ctx)
 
 static void draw_update(struct draw_ctx *dctx, int x, int y, int w, int h)
 {
-#ifndef NO_BACKING_PIXMAPS
-#ifdef DRAW_TEXT_GDK
-    if (dctx->uctx.type == DRAWTYPE_GDK) {
-        gdk_draw_pixmap(gtk_widget_get_window(dctx->inst->area),
-                        dctx->uctx.u.gdk.gc, dctx->inst->pixmap,
-                        x, y, x, y, w, h);
-    }
-#endif
-#ifdef DRAW_TEXT_CAIRO /* FIXME: and not GTK3 where a cairo_t is all we have */
+#if defined DRAW_TEXT_CAIRO && !defined NO_BACKING_PIXMAPS
     if (dctx->uctx.type == DRAWTYPE_CAIRO) {
-        GdkGC *gc = gdk_gc_new(gtk_widget_get_window(dctx->inst->area));
-        gdk_draw_pixmap(gtk_widget_get_window(dctx->inst->area),
-                        gc, dctx->inst->pixmap, x, y, x, y, w, h);
-        gdk_gc_unref(gc);
+        /*
+         * If inst->surface and inst->pixmap both exist, then we've
+         * just drawn new content to the former which we must copy to
+         * the latter.
+         */
+        cairo_t *cr = gdk_cairo_create(dctx->inst->pixmap);
+        cairo_set_source_surface(cr, dctx->inst->surface, 0, 0);
+        cairo_rectangle(cr, x, y, w, h);
+        cairo_fill(cr);
+        cairo_destroy(cr);
     }
 #endif
-#endif
+
+    /*
+     * Now we just queue a window redraw, which will cause
+     * inst->surface or inst->pixmap (whichever is appropriate for our
+     * compile mode) to be copied to the real window when we receive
+     * the resulting "expose" or "draw" event.
+     *
+     * Amazingly, this one API call is actually valid in all versions
+     * of GTK :-)
+     */
+    gtk_widget_queue_draw_area(dctx->inst->area, x, y, w, h);
 }
 
 static void draw_set_colour(struct draw_ctx *dctx, int col)
@@ -3080,10 +3371,11 @@ static void draw_stretch_after(struct draw_ctx *dctx, int x, int y,
 static void draw_backing_rect(struct gui_data *inst)
 {
     struct draw_ctx *dctx = get_ctx(inst);
+    int w = inst->width * inst->font_width + 2*inst->window_border;
+    int h = inst->height * inst->font_height + 2*inst->window_border;
     draw_set_colour(dctx, 258);
-    draw_rectangle(dctx, 1, 0, 0,
-                   inst->width * inst->font_width + 2*inst->window_border,
-                   inst->height * inst->font_height + 2*inst->window_border);
+    draw_rectangle(dctx, 1, 0, 0, w, h);
+    draw_update(dctx, 0, 0, w, h);
     free_ctx(dctx);
 }
 
@@ -3098,7 +3390,7 @@ void do_text_internal(Context ctx, int x, int y, wchar_t *text, int len,
 {
     struct draw_ctx *dctx = (struct draw_ctx *)ctx;
     struct gui_data *inst = dctx->inst;
-    int ncombining, combining;
+    int ncombining;
     int nfg, nbg, t, fontid, shadow, rlen, widefactor, bold;
     int monochrome =
         gdk_visual_get_depth(gtk_widget_get_visual(inst->area)) == 1;
@@ -3195,11 +3487,20 @@ void do_text_internal(Context ctx, int x, int y, wchar_t *text, int len,
                    rlen*widefactor*inst->font_width, inst->font_height);
 
     draw_set_colour(dctx, nfg);
-    for (combining = 0; combining < ncombining; combining++) {
+    if (ncombining > 1) {
+        assert(len == 1);
+        unifont_draw_combining(&dctx->uctx, inst->fonts[fontid],
+                               x*inst->font_width+inst->window_border,
+                               (y*inst->font_height+inst->window_border+
+                                inst->fonts[0]->ascent),
+                               text, ncombining, widefactor > 1,
+                               bold, inst->font_width);
+    } else {
         unifont_draw_text(&dctx->uctx, inst->fonts[fontid],
                           x*inst->font_width+inst->window_border,
-                          y*inst->font_height+inst->window_border+inst->fonts[0]->ascent,
-                          text + combining, len, widefactor > 1,
+                          (y*inst->font_height+inst->window_border+
+                           inst->fonts[0]->ascent),
+                          text, len, widefactor > 1,
                           bold, inst->font_width);
     }
 
@@ -4521,6 +4822,9 @@ int pt_main(int argc, char **argv)
     inst->quit_fn_scheduled = FALSE;
     inst->idle_fn_scheduled = FALSE;
     inst->drawtype = DRAWTYPE_DEFAULT;
+#if GTK_CHECK_VERSION(3,4,0)
+    inst->cumulative_scroll = 0.0;
+#endif
 
     /* defer any child exit handling until we're ready to deal with
      * it */
@@ -4603,6 +4907,12 @@ int pt_main(int argc, char **argv)
 
     init_clipboard(inst);
 
+    set_geom_hints(inst);
+
+#if GTK_CHECK_VERSION(3,0,0)
+    gtk_window_set_default_geometry(GTK_WINDOW(inst->window),
+                                    inst->width, inst->height);
+#else
     {
         int w = inst->font_width * inst->width + 2*inst->window_border;
         int h = inst->font_height * inst->height + 2*inst->window_border;
@@ -4612,6 +4922,8 @@ int pt_main(int argc, char **argv)
         gtk_drawing_area_size(GTK_DRAWING_AREA(inst->area), w, h);
 #endif
     }
+#endif
+
     inst->sbar_adjust = GTK_ADJUSTMENT(gtk_adjustment_new(0,0,0,0,0,0));
     inst->sbar = gtk_vscrollbar_new(inst->sbar_adjust);
     inst->hbox = GTK_BOX(gtk_hbox_new(FALSE, 0));
@@ -4628,8 +4940,6 @@ int pt_main(int argc, char **argv)
 
     gtk_container_add(GTK_CONTAINER(inst->window), GTK_WIDGET(inst->hbox));
 
-    set_geom_hints(inst);
-
     gtk_widget_show(inst->area);
     if (conf_get_int(inst->conf, CONF_scrollbar))
        gtk_widget_show(inst->sbar);
@@ -4694,7 +5004,11 @@ int pt_main(int argc, char **argv)
     gtk_widget_add_events(GTK_WIDGET(inst->area),
                          GDK_KEY_PRESS_MASK | GDK_KEY_RELEASE_MASK |
                          GDK_BUTTON_PRESS_MASK | GDK_BUTTON_RELEASE_MASK |
-                         GDK_POINTER_MOTION_MASK | GDK_BUTTON_MOTION_MASK);
+                         GDK_POINTER_MOTION_MASK | GDK_BUTTON_MOTION_MASK
+#if GTK_CHECK_VERSION(3,4,0)
+                          | GDK_SMOOTH_SCROLL_MASK
+#endif
+        );
 
     {
        extern const char *const *const main_icon[];