From 5ed2574fb8ccf6974597e804ca7b6b3d2b46c84f Mon Sep 17 00:00:00 2001
From: Colin Clark <colin.clark@cclark.uk>
Date: Fri, 8 Sep 2017 17:11:02 +0100
Subject: [PATCH] Fix #278: Shortcut to change time between images in slideshow

https://github.com/BestImageViewer/geeqie/issues/278

Keypad plus and minus to change the interval in 0.5 sec units.
---
 doc/docbook/GuideMainWindowMenus.xml          | 16 +++++++++++
 .../GuideReferenceKeyboardShortcuts.xml       | 27 +++++++++++++++++++
 src/layout_util.c                             | 24 +++++++++++++++++
 src/slideshow.c                               |  5 ++++
 4 files changed, 72 insertions(+)

diff --git a/doc/docbook/GuideMainWindowMenus.xml b/doc/docbook/GuideMainWindowMenus.xml
index a0ee5858..608f60cf 100644
--- a/doc/docbook/GuideMainWindowMenus.xml
+++ b/doc/docbook/GuideMainWindowMenus.xml
@@ -1376,6 +1376,22 @@
           <para>Pauses a slide show, the slide show status is displayed in the status bar.</para>
         </listitem>
       </varlistentry>
+      <varlistentry>
+        <term>
+          <guimenu>Faster</guimenu>
+        </term>
+        <listitem>
+          <para>Decreases slide show interval in units of 0.5 seconds.</para>
+        </listitem>
+      </varlistentry>
+      <varlistentry>
+        <term>
+          <guimenu>Slower</guimenu>
+        </term>
+        <listitem>
+          <para>Increases slide show interval in units of 0.5 seconds.</para>
+        </listitem>
+      </varlistentry>
       <varlistentry>
         <term>
           <guimenu>Refresh</guimenu>
diff --git a/doc/docbook/GuideReferenceKeyboardShortcuts.xml b/doc/docbook/GuideReferenceKeyboardShortcuts.xml
index c6cd6c22..de3736c8 100644
--- a/doc/docbook/GuideReferenceKeyboardShortcuts.xml
+++ b/doc/docbook/GuideReferenceKeyboardShortcuts.xml
@@ -667,6 +667,33 @@
             <entry />
             <entry>Toggle slideshow.</entry>
           </row>
+          <row>
+            <entry>
+              <keycap>P</keycap>
+            </entry>
+            <entry />
+            <entry>Pause slideshow.</entry>
+          </row>
+          <row>
+            <entry>
+              <code>
+                Ctrl +
+                <keycap>Keypad +</keycap>
+              </code>
+            </entry>
+            <entry />
+            <entry>Slideshow faster.</entry>
+          </row>
+          <row>
+            <entry>
+              <code>
+                Ctrl +
+                <keycap>Keypad -</keycap>
+              </code>
+            </entry>
+            <entry />
+            <entry>Slideshow slower.</entry>
+          </row>
           <row>
             <entry>
               <keycap>E</keycap>
diff --git a/src/layout_util.c b/src/layout_util.c
index ffa91c2e..c8a83f9a 100644
--- a/src/layout_util.c
+++ b/src/layout_util.c
@@ -45,6 +45,7 @@
 #include "preferences.h"
 #include "print.h"
 #include "search.h"
+#include "slideshow.h"
 #include "ui_fileops.h"
 #include "ui_menu.h"
 #include "ui_misc.h"
@@ -1017,6 +1018,24 @@ static void layout_menu_slideshow_pause_cb(GtkAction *action, gpointer data)
 	layout_image_slideshow_pause_toggle(lw);
 }
 
+static void layout_menu_slideshow_slower_cb(GtkAction *action, gpointer data)
+{
+	LayoutWindow *lw = data;
+
+	options->slideshow.delay = options->slideshow.delay + 5;
+	if (options->slideshow.delay > SLIDESHOW_MAX_SECONDS)
+		options->slideshow.delay = SLIDESHOW_MAX_SECONDS;
+}
+
+static void layout_menu_slideshow_faster_cb(GtkAction *action, gpointer data)
+{
+	LayoutWindow *lw = data;
+
+	options->slideshow.delay = options->slideshow.delay - 5;
+	if (options->slideshow.delay < SLIDESHOW_MIN_SECONDS * 10)
+		options->slideshow.delay = SLIDESHOW_MIN_SECONDS * 10;
+}
+
 
 static void layout_menu_stereo_mode_next_cb(GtkAction *action, gpointer data)
 {
@@ -1812,6 +1831,8 @@ static GtkActionEntry menu_entries[] = {
   { "HistogramModeCycle",NULL,			N_("Cycle through histogram mo_des"),	"J",			N_("Cycle through histogram modes"),	CB(layout_menu_histogram_toggle_mode_cb) },
   { "HideTools",	NULL,			N_("_Hide file list"),			"<control>H",		N_("Hide file list"),			CB(layout_menu_hide_cb) },
   { "SlideShowPause",	GTK_STOCK_MEDIA_PAUSE,	N_("_Pause slideshow"), 		"P",			N_("Pause slideshow"), 			CB(layout_menu_slideshow_pause_cb) },
+  { "SlideShowFaster",	NULL,	N_("Faster"), 		"<control>KP_Add",			N_("Faster"), 			CB(layout_menu_slideshow_faster_cb) },
+  { "SlideShowSlower",	NULL,	N_("Slower"), 		"<control>KP_Subtract",			N_("Slower"), 			CB(layout_menu_slideshow_slower_cb) },
   { "Refresh",		GTK_STOCK_REFRESH,	N_("_Refresh"),				"R",			N_("Refresh"),				CB(layout_menu_refresh_cb) },
   { "HelpContents",	GTK_STOCK_HELP,		N_("_Contents"),			"F1",			N_("Contents"),				CB(layout_menu_help_cb) },
   { "HelpShortcuts",	NULL,			N_("_Keyboard shortcuts"),		NULL,			N_("Keyboard shortcuts"),		CB(layout_menu_help_keys_cb) },
@@ -2106,6 +2127,9 @@ static const gchar *menu_ui_description =
 "      <menuitem action='Animate'/>"
 "      <menuitem action='SlideShow'/>"
 "      <menuitem action='SlideShowPause'/>"
+"      <menuitem action='SlideShowFaster'/>"
+"      <menuitem action='SlideShowSlower'/>"
+"      <separator/>"
 "      <menuitem action='Refresh'/>"
 "      <placeholder name='SlideShowSection'/>"
 "      <separator/>"
diff --git a/src/slideshow.c b/src/slideshow.c
index 089e5a17..515a24fc 100644
--- a/src/slideshow.c
+++ b/src/slideshow.c
@@ -304,6 +304,8 @@ static gboolean slideshow_step(SlideShowData *ss, gboolean forward)
 	return TRUE;
 }
 
+static void slideshow_timer_reset(SlideShowData *ss);
+
 static gboolean slideshow_loop_cb(gpointer data)
 {
 	SlideShowData *ss = data;
@@ -317,6 +319,9 @@ static gboolean slideshow_loop_cb(gpointer data)
 		return FALSE;
 		}
 
+	/* Check if the user has changed the timer interval */
+	slideshow_timer_reset(ss);
+
 	return TRUE;
 }
 
-- 
2.20.1