Adding shadows!

tests/intersect_test.cpp

@@ -9,9 +9,9 @@
 #include <intersect.h>
 #include <intersection.h>
 #include <sphere.h>
+#include <transformation.h>
 #include <gtest/gtest.h>
 
-
 TEST(IntersectTest, Creating_an_intersect_and_do_some_check)
 {
     Intersect i;
@@ -173,4 +173,20 @@ TEST(IntersectTest, The_hit_when_an_intersection_occurs_on_the_inside)
     /* Normal vector would have been (0, 0, 1); but is inverted ! */
 
     ASSERT_EQ(comps.normalVector, Vector(0, 0, -1));
+}
+
+TEST(IntersectTest, The_hit_should_offset_the_point)
+{
+    Ray r = Ray(Point(0, 0, -5), Vector(0, 0, 1));
+    Sphere shape = Sphere();
+    shape.setTransform(translation(0, 0, 1));
+
+    Intersection i = Intersection(5, &shape);
+
+    Computation comps = i.prepareComputation(r);
+
+    /* Normal vector would have been (0, 0, 1); but is inverted ! */
+
+    ASSERT_LT(comps.overHitPoint.z, -getEpsilon() / 2);
+    ASSERT_GT(comps.hitPoint.z, comps.overHitPoint.z);
 }

tests/material_test.cpp

@@ -86,5 +86,17 @@ TEST(MaterialTest, Lighting_with_the_light_behind_the_surface)
 
     Colour result = m.lighting(light, position, eyev, normalv);
 
+    ASSERT_EQ(result, Colour(0.1, 0.1, 0.1));
+}
+
+TEST(MaterialTest, Lighting_with_the_surface_in_shadow)
+{
+    Vector eyev = Vector(0, 0, -1);
+    Vector normalv = Vector(0, 0, -1);
+    Light light = Light(POINT_LIGHT, Point(0, 0, -10), Colour(1, 1, 1));
+    bool inShadow = true;
+
+    Colour result = m.lighting(light, position, eyev, normalv, inShadow);
+
     ASSERT_EQ(result, Colour(0.1, 0.1, 0.1));
 }

tests/world_test.cpp

@@ -111,4 +111,60 @@ TEST(WorldTest, The_colour_with_an_intersection_behind_the_ray)
     Tuple c = w.colourAt(r);
 
     ASSERT_EQ(c, inner->material.colour);
-}
+}
+
+TEST(WorldTest, There_is_no_shadow_when_nothing_is_collinear_with_point_and_light)
+{
+    World w = DefaultWorld();
+    Tuple p = Point(0, 10, 0);
+
+    ASSERT_FALSE(w.isShadowed(p));
+}
+
+TEST(WorldTest, The_shadow_when_an_object_is_between_the_point_and_the_light)
+{
+    World w = DefaultWorld();
+    Tuple p = Point(10, -10, 10);
+
+    ASSERT_TRUE(w.isShadowed(p));
+}
+
+TEST(WorldTest, There_is_no_shadow_whne_an_object_is_behing_the_light)
+{
+    World w = DefaultWorld();
+    Tuple p = Point(-20, 20, -20);
+
+    ASSERT_FALSE(w.isShadowed(p));
+}
+
+TEST(WorldTest, There_is_no_shadow_when_an_object_is_behing_the_point)
+{
+    World w = DefaultWorld();
+    Tuple p = Point(-2, 2, -2);
+
+    ASSERT_FALSE(w.isShadowed(p));
+}
+
+TEST(WorldTest, Shade_hit_is_given_an_intersection_in_shadow)
+{
+    World w = World();
+
+    Light l = Light(POINT_LIGHT, Point(0, 0, -10), Colour(1, 1, 1));
+    w.addLight(&l);
+
+    Sphere s1 = Sphere();
+
+    w.addObject(&s1);
+
+    Sphere s2 = Sphere();
+    s2.setTransform(translation(0, 0, 10));
+
+    w.addObject(&s2);
+
+    Ray r = Ray(Point(0, 0, 5), Vector(0, 0, 1));
+    Intersection i = Intersection(4, &s2);
+    Computation comps = i.prepareComputation(r);
+    Tuple c = w.shadeHit(comps);
+
+    ASSERT_EQ(c, Colour(0.1, 0.1, 0.1));
+};