eeshow/: add online help with h or ? (WIP)

eeshow/Makefile

@@ -16,6 +16,7 @@ OBJS = main.o \
        kicad/lib-render.o kicad/dwg.o kicad/delta.o \
        gui/gui.o gui/over.o gui/style.o gui/aoi.o gui/fmt-pango.o gui/input.o \
        gui/progress.o gui/glabel.o gui/sheet.o gui/history.o gui/render.o \
+       gui/help.o \
        file/file.o file/git-util.o file/git-file.o file/git-hist.o \
        gfx/style.o gfx/fig.o gfx/record.o gfx/cro.o gfx/diff.o gfx/gfx.o \
        gfx/text.o gfx/misc.o \
@@ -26,11 +27,13 @@ CFLAGS = -g  -Wall -Wextra -Wno-unused-parameter -Wshadow \
 	 -I. \
 	 `pkg-config --cflags cairo` \
 	 `pkg-config --cflags libgit2` \
-	 `pkg-config --cflags gtk+-3.0`
+	 `pkg-config --cflags gtk+-3.0` \
+	 `pkg-config --cflags webkit2gtk-3.0`
 LDLIBS = -lm \
 	 `pkg-config --libs cairo` \
 	 `pkg-config --libs libgit2` \
-	 `pkg-config --libs gtk+-3.0`
+	 `pkg-config --libs gtk+-3.0` \
+	 `pkg-config --libs webkit2gtk-3.0`
 
 include ../common/Makefile.c-common
 
@@ -41,6 +44,14 @@ all::		$(NAME)
 $(NAME):	$(OBJS)
 		$(CC) -o $(NAME) $(OBJS) $(LDLIBS)
 
+help.inc:	help.html
+		$(BUILD) sed 's/.*/"&"/' $< >$@ || { rm -f $@; exit 1; }
+
+gui/help.c:	help.inc
+
+clean::
+		rm -f help.inc
+
 #----- Test sheet -------------------------------------------------------------
 
 sch:

eeshow/README

@@ -25,6 +25,7 @@ Prerequisites
 libcairo2-dev
 libgit2-dev
 libgtk-3-dev
+ibwebkit2gtk-3.0-dev
 
 
 Development status
@@ -45,7 +46,6 @@ many limitations, especially in the following areas:
 More details on pending items can be found in the file TODO.
 
 
-
 Non-interactive rendering
 =========================
 
@@ -175,6 +175,7 @@ PgUp			go to the previous sheet in sequence
 PgDn			go to the next sheet in sequence
 Up or Down		invoke the revision history (WIP)
 Tab			toggle between old and new revision
+? or H			show/hide help window
 D			when comparing revisions, show difference (default)
 N			show newer sheet
 O			show older sheet

eeshow/gui/help.c

@@ -0,0 +1,57 @@
+/*
+ * gui/help.c - Online help
+ *
+ * Written 2016 by Werner Almesberger
+ * Copyright 2016 by Werner Almesberger
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <stdbool.h>
+
+#include <gtk/gtk.h>
+#include <webkit2/webkit2.h>
+
+#include "gui/help.h"
+
+
+static GtkWidget *window = NULL;
+static bool visible;
+
+
+static void new_help_window(void)
+{
+	GtkWidget *view;
+
+	window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
+	view = webkit_web_view_new();
+	gtk_container_add(GTK_CONTAINER(window), view);
+	gtk_widget_show_all(window);
+
+	webkit_web_view_load_html(WEBKIT_WEB_VIEW(view),
+#include "../help.inc"
+	, NULL);
+
+	g_signal_connect(window, "destroy",
+	    G_CALLBACK(gtk_main_quit), NULL);
+
+	gtk_widget_show_all(window);
+}
+
+
+void help(void)
+{
+	if (!window) {
+		new_help_window();
+		visible = 1;
+	} else {
+		visible = !visible;
+		if (visible)
+			gtk_widget_show(window);
+		else
+			gtk_widget_hide(window);
+	}
+}

eeshow/gui/help.h

@@ -0,0 +1,18 @@
+/*
+ * gui/help.h - Online help
+ *
+ * Written 2016 by Werner Almesberger
+ * Copyright 2016 by Werner Almesberger
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef GUI_HELP_H
+#define	GUI_HELP_H
+
+void help(void);
+
+#endif /* !GUI_HELP_H */

eeshow/gui/sheet.c

@@ -24,6 +24,7 @@
 #include "gui/aoi.h"
 #include "gui/over.h"
 #include "gui/input.h"
+#include "gui/help.h"
 #include "gui/common.h"
 
 
@@ -515,6 +516,11 @@ static void sheet_key(void *user, int x, int y, int keyval)
 		redraw(ctx);
 		break;
 
+	case GDK_KEY_h:
+	case GDK_KEY_question:
+		help();
+		break;
+
 	case GDK_KEY_q:
 		gtk_main_quit();
 	}

eeshow/help.html

@@ -0,0 +1,48 @@
+<HTML>
+<HEAD><TITLE>Eeshow help</TITLE></HEAD>
+
+<H1>Key functions in GUI mode</H1>
+
+<TABLE>
+  <TR>
+    <TD>+ or =
+    <TD>zoom in
+  <TR>
+    <TD>-
+    <TD>zoom out
+  <TR>
+    <TD>*
+    <TD>zoom to extents
+  <TR>
+    <TD>Home
+    <TD>go to the top sheet
+  <TR>
+    <TD>Delete or Backspace
+    <TD>go to the next higher sheet in hierarchy
+  <TR>
+    <TD>PgUp
+    <TD>go to the previous sheet in sequence
+  <TR>
+    <TD>PgDn
+    <TD>go to the next sheet in sequence
+  <TR>
+    <TD>Tab
+    <TD>toggle between old and new revision
+  <TR>
+    <TD>? or H
+    <TD>open/close help window
+  <TR>
+    <TD>D
+    <TD>when comparing revisions, show difference
+  <TR>
+    <TD>N
+    <TD>show newer sheet
+  <TR>
+    <TD>O
+    <TD>show older sheet
+  <TR>
+    <TD>Q
+    <TD>quit the vieweer
+</TABLE>
+</BODY>
+</HTML>