World is on the verge of working!

tests/intersect_test.cpp

@@ -7,6 +7,7 @@
  *
  */
 #include <intersect.h>
+#include <intersection.h>
 #include <sphere.h>
 #include <gtest/gtest.h>
 
@@ -129,4 +130,47 @@ TEST(IntersectTest, The_hit_is_always_the_lowest_nonnegative_intersection)
     Intersection i = xs.hit();
 
     ASSERT_EQ(i, i4);
+}
+
+TEST(IntersectTest, Precomputing_the_state_of_an_intersection)
+{
+    Ray r = Ray(Point(0, 0, -5), Vector(0, 0, 1));
+    Sphere shape = Sphere();
+    Intersection i = Intersection(4, &shape);
+
+    Computation comps = i.prepareComputation(r);
+
+    ASSERT_EQ(comps.t, i.t);
+    ASSERT_EQ(comps.object, i.object);
+    ASSERT_EQ(comps.hitPoint, Point(0, 0, -1));
+    ASSERT_EQ(comps.eyeVector, Vector(0, 0, -1));
+    ASSERT_EQ(comps.normalVector, Vector(0, 0, -1));
+
+}
+
+TEST(IntersectTest, The_hit_when_an_intersection_occurs_on_the_outside)
+{
+    Ray r = Ray(Point(0, 0, -5), Vector(0, 0, 1));
+    Sphere shape = Sphere();
+    Intersection i = Intersection(4, &shape);
+
+    Computation comps = i.prepareComputation(r);
+
+    ASSERT_EQ(comps.inside, false);
+}
+
+TEST(IntersectTest, The_hit_when_an_intersection_occurs_on_the_inside)
+{
+    Ray r = Ray(Point(0, 0, 0), Vector(0, 0, 1));
+    Sphere shape = Sphere();
+    Intersection i = Intersection(1, &shape);
+
+    Computation comps = i.prepareComputation(r);
+    ASSERT_EQ(comps.hitPoint, Point(0, 0, 1));
+    ASSERT_EQ(comps.eyeVector, Vector(0, 0, -1));
+    ASSERT_EQ(comps.inside, true);
+
+    /* Normal vector would have been (0, 0, 1); but is inverted ! */
+
+    ASSERT_EQ(comps.normalVector, Vector(0, 0, -1));
 }

tests/world_test.cpp

@@ -58,3 +58,57 @@ TEST(WorldTest, Intersect_a_world_with_a_ray)
     ASSERT_EQ(xs[3].t, 6);
 }
 
+TEST(WorldTest, Shading_an_intersection)
+{
+    World w = DefaultWorld();
+    Ray r = Ray(Point(0, 0, -5), Vector(0, 0, 1));
+    Shape *s = w.getObject(0);
+    Intersection i = Intersection(4, s);
+    Computation comps = i.prepareComputation(r);
+    Tuple c = w.shadeHit(comps);
+
+    /* Temporary lower the precision */
+    set_equal_precision(0.00001);
+
+    ASSERT_EQ(c, Colour(0.38066, 0.47583, 0.2855));
+
+    set_equal_precision(FLT_EPSILON);
+}
+
+TEST(WorldTest, The_when_ray_miss)
+{
+    World w = DefaultWorld();
+    Ray r = Ray(Point(0, 0, -5), Vector(0, 1, 0));
+    Tuple c = w.colourAt(r);
+
+    ASSERT_EQ(c, Colour(0, 0, 0));
+}
+
+TEST(WorldTest, The_when_ray_hit)
+{
+    World w = DefaultWorld();
+    Ray r = Ray(Point(0, 0, -5), Vector(0, 0, 1));
+    Tuple c = w.colourAt(r);
+
+    /* Temporary lower the precision */
+    set_equal_precision(0.00001);
+
+    ASSERT_EQ(c, Colour(0.38066, 0.47583, 0.2855));
+
+    set_equal_precision(FLT_EPSILON);
+}
+
+TEST(WorldTest, The_colour_with_an_intersection_behind_the_ray)
+{
+    World w = DefaultWorld();
+    Shape *outer = w.getObject(0);
+    outer->material.ambient = 1;
+    Shape *inner = w.getObject(1);
+    inner->material.ambient = 1;
+
+    Ray r = Ray(Point(0, 0, 0.75), Vector(0, 0, -1));
+
+    Tuple c = w.colourAt(r);
+
+    ASSERT_EQ(c, inner->material.colour);
+}