Add operator< for VerticalPosition.

4 files changed, 130 insertions, 0 deletions

diff --git a/src/vertical_position.cc b/src/vertical_position.cc
index cdf0b6c..37930d0 100644
--- a/src/vertical_position.cc
+++ b/src/vertical_position.cc
@@ -21,6 +21,29 @@
 
 using namespace sub;
 
+float
+VerticalPosition::fraction_from_screen_top () const
+{
+	if (!reference || (!proportional && !line)) {
+		return 0;
+	}
+
+	float const prop = proportional ? proportional.get() : (float (line.get()) / lines.get ());
+	
+	switch (reference.get ()) {
+	case TOP_OF_SCREEN:
+		return prop;
+	case CENTRE_OF_SCREEN:
+		return prop + 0.5;
+	case BOTTOM_OF_SCREEN:
+		return 1 - prop;
+	case TOP_OF_SUBTITLE:
+		return prop;
+	}
+
+	return 0;
+}
+
 bool
 VerticalPosition::operator== (VerticalPosition const & other) const
 {
@@ -32,3 +55,11 @@ VerticalPosition::operator== (VerticalPosition const & other) const
 
 	return false;
 }
+
+bool
+VerticalPosition::operator< (VerticalPosition const & other) const
+{
+	return fraction_from_screen_top() < other.fraction_from_screen_top();
+}
+
+	
diff --git a/src/vertical_position.h b/src/vertical_position.h
index 77b0675..9f04056 100644
--- a/src/vertical_position.h
+++ b/src/vertical_position.h
@@ -41,6 +41,9 @@ public:
 	boost::optional<VerticalReference> reference;
 	
 	bool operator== (VerticalPosition const & other) const;
+	bool operator< (VerticalPosition const & other) const;
+
+	float fraction_from_screen_top () const;
 };
 	
 }
diff --git a/test/vertical_position_test.cc b/test/vertical_position_test.cc
new file mode 100644
index 0000000..3204113
--- /dev/null
+++ b/test/vertical_position_test.cc
@@ -0,0 +1,95 @@
+/*
+    Copyright (C) 2015 Carl Hetherington <cth@carlh.net>
+
+    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.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#include "vertical_position.h"
+#include <boost/test/unit_test.hpp>
+
+using boost::optional;
+
+/* Test operator< for VerticalPosition */
+BOOST_AUTO_TEST_CASE (vertical_position_test)
+{
+	sub::VerticalPosition a;
+	sub::VerticalPosition b;
+	
+	/* Simple */
+	
+	a.proportional = 0.3;
+	a.reference = sub::TOP_OF_SCREEN;
+	b.proportional = 0.4;
+	b.reference = sub::TOP_OF_SCREEN;
+	BOOST_CHECK (a < b);
+
+	a.proportional = 0.5;
+	a.reference = sub::TOP_OF_SCREEN;
+	b.proportional = 0.1;
+	b.reference = sub::TOP_OF_SCREEN;
+	BOOST_CHECK (b < a);
+
+	a.proportional = optional<float> ();
+	b.proportional = optional<float> ();
+
+	a.line = 4;
+	a.lines = 25;
+	a.reference = sub::TOP_OF_SCREEN;
+	b.line = 6;
+	b.lines = 25;
+	b.reference = sub::TOP_OF_SCREEN;
+	BOOST_CHECK (a < b);
+
+	a.line = 17;
+	a.lines = 25;
+	a.reference = sub::TOP_OF_SCREEN;
+	b.line = 2;
+	b.lines = 25;
+	b.reference = sub::TOP_OF_SCREEN;
+	BOOST_CHECK (b < a);
+
+	/* Different reference points with proportional */
+
+	a.line = optional<int> ();
+	a.lines = optional<int> ();
+	b.line = optional<int> ();
+	b.lines = optional<int> ();
+
+	a.proportional = 0.7;
+	a.reference = sub::TOP_OF_SCREEN;
+	b.proportional = 0.3;
+	b.reference = sub::CENTRE_OF_SCREEN;
+	BOOST_CHECK (a < b);
+
+	a.proportional = 0.9;
+	a.reference = sub::BOTTOM_OF_SCREEN;
+	b.proportional = 0.1;
+	b.reference = sub::TOP_OF_SCREEN;
+	BOOST_CHECK (b < a);
+
+	/* Different line counts with lines */
+	
+	a.proportional = optional<float> ();
+	b.proportional = optional<float> ();
+
+	a.line = 12;
+	a.lines = 99;
+	a.reference = sub::TOP_OF_SCREEN;
+	b.line = 12;
+	b.lines = 25;
+	b.reference = sub::TOP_OF_SCREEN;
+	BOOST_CHECK (a < b);
+}
diff --git a/test/wscript b/test/wscript
index 2c8c327..286f62f 100644
--- a/test/wscript
+++ b/test/wscript
@@ -29,6 +29,7 @@ def build(bld):
                  subrip_reader_test.cc
                  time_test.cc
                  test.cc
+                 vertical_position_test.cc
                  """
     obj.target = 'tests'
     obj.install_path = ''