From 7d3ab0dcce7abb6d5f766315685424e82478212f Mon Sep 17 00:00:00 2001
From: Daniel Karbach <daniel.karbach@localhorst.tv>
Date: Thu, 11 Jun 2015 15:29:35 +0200
Subject: [PATCH] fix ray/obb intersection test

again, unit tests \o/

also: careful with the signs ;)
---
 src/model/geometry.cpp     |  2 +-
 tst/model/GeometryTest.cpp | 41 ++++++++++++++++++++++++++++++++++++++
 tst/model/GeometryTest.hpp | 30 ++++++++++++++++++++++++++++
 3 files changed, 72 insertions(+), 1 deletion(-)
 create mode 100644 tst/model/GeometryTest.cpp
 create mode 100644 tst/model/GeometryTest.hpp

diff --git a/src/model/geometry.cpp b/src/model/geometry.cpp
index 416d930..ed9b4b7 100644
--- a/src/model/geometry.cpp
+++ b/src/model/geometry.cpp
@@ -35,7 +35,7 @@ bool Intersection(
 				return false;
 			}
 		} else {
-			if (aabb.min[i] - e < 0.0f || -aabb.max[i] - e > 0.0f) {
+			if (aabb.min[i] - e > 0.0f || aabb.max[i] - e < 0.0f) {
 				return false;
 			}
 		}
diff --git a/tst/model/GeometryTest.cpp b/tst/model/GeometryTest.cpp
new file mode 100644
index 0000000..3776da1
--- /dev/null
+++ b/tst/model/GeometryTest.cpp
@@ -0,0 +1,41 @@
+#include "GeometryTest.hpp"
+
+#include "model/geometry.hpp"
+
+#include <limits>
+
+CPPUNIT_TEST_SUITE_REGISTRATION(blank::test::GeometryTest);
+
+
+namespace blank {
+namespace test {
+
+void GeometryTest::setUp() {
+}
+
+void GeometryTest::tearDown() {
+}
+
+
+void GeometryTest::testRayAABBIntersection() {
+	Ray ray{ { 0, 0, 0 }, { 1, 0, 0 } }; // at origin, pointing right
+	AABB box{ { -1, -1, -1 }, { 1, 1, 1 } }; // 2x2x2 cube centered around origin
+	glm::mat4 M(1); // no transformation
+
+	const float delta = std::numeric_limits<float>::epsilon();
+
+	float distance = 0;
+	glm::vec3 normal(0);
+
+	CPPUNIT_ASSERT_MESSAGE(
+		"ray at origin not intersecting box at origin",
+		Intersection(ray, box, M, &distance, &normal)
+	);
+	CPPUNIT_ASSERT_DOUBLES_EQUAL_MESSAGE(
+		"intersection distance way off",
+		0.0f, distance, delta
+	);
+}
+
+}
+}
diff --git a/tst/model/GeometryTest.hpp b/tst/model/GeometryTest.hpp
new file mode 100644
index 0000000..2ee85b1
--- /dev/null
+++ b/tst/model/GeometryTest.hpp
@@ -0,0 +1,30 @@
+#ifndef BLANK_TEST_MODEL_GEOMETRYTEST_H_
+#define BLANK_TEST_MODEL_GEOMETRYTEST_H_
+
+#include <cppunit/extensions/HelperMacros.h>
+
+
+namespace blank {
+namespace test {
+
+class GeometryTest
+: public CppUnit::TestFixture {
+
+CPPUNIT_TEST_SUITE(GeometryTest);
+
+CPPUNIT_TEST(testRayAABBIntersection);
+
+CPPUNIT_TEST_SUITE_END();
+
+public:
+	void setUp();
+	void tearDown();
+
+	void testRayAABBIntersection();
+
+};
+
+}
+}
+
+#endif
-- 
2.39.2