Added random sampling test case

Signed-off-by: Julius Nehring-Wirxel julius.nehring-wirxel@rwth-aachen.de

tests/geometry/interesections/aabb-intersect.cc

@@ -5,22 +5,13 @@ TG_FUZZ_TEST(AABB, Intersect)
     auto const bounds = tg::aabb3(-10, 10);
 
     {
-        auto const min_a = tg::uniform(rng, bounds);
-        auto const max_a = tg::uniform(rng, tg::aabb3(min_a, bounds.max));
+        auto const min_a = uniform(rng, bounds);
+        auto const max_a = uniform(rng, tg::aabb3(min_a, bounds.max));
 
         auto const aabb_a = tg::aabb3(min_a, max_a);
 
-        tg::pos3 inside;
-        do
-        {
-            // must be truly inside
-            inside = tg::uniform(rng, aabb_a);
-        } while (aabb_a.min.x >= inside.x || inside.x >= aabb_a.max.x || //
-                 aabb_a.min.y >= inside.y || inside.y >= aabb_a.max.y || //
-                 aabb_a.min.z >= inside.z || inside.z >= aabb_a.max.z);
-
-
-        auto const other = tg::uniform(rng, bounds);
+        auto const inside = uniform(rng, aabb_a);
+        auto const other = uniform(rng, bounds);
 
         const tg::pos3 min_b = {
             tg::min(inside.x, other.x),
@@ -46,26 +37,26 @@ TG_FUZZ_TEST(AABB, NonIntersect)
     auto const bounds = tg::aabb3(-10, 10);
 
     {
-        auto const min_a = tg::uniform(rng, bounds);
-        auto const max_a = tg::uniform(rng, tg::aabb3(min_a, bounds.max));
+        auto const min_a = uniform(rng, bounds);
+        auto const max_a = uniform(rng, tg::aabb3(min_a, bounds.max));
 
         auto const aabb_a = tg::aabb3(min_a, max_a);
 
-        auto min_b = tg::uniform(rng, bounds);
-        auto max_b = tg::uniform(rng, tg::aabb3(min_b, bounds.max));
+        auto min_b = uniform(rng, bounds);
+        auto max_b = uniform(rng, tg::aabb3(min_b, bounds.max));
 
         // generate one separating axis
-        auto const dim = tg::uniform(rng, {0, 1, 2});
-        auto const dir = tg::uniform(rng, {true, false});
+        auto const dim = uniform(rng, {0, 1, 2});
+        auto const dir = uniform(rng, {true, false});
         if (dir)
         {
-            min_b[dim] = tg::uniform(rng, max_a[dim], bounds.max[dim]);
-            max_b[dim] = tg::uniform(rng, min_b[dim], bounds.max[dim]);
+            min_b[dim] = uniform(rng, max_a[dim], bounds.max[dim]);
+            max_b[dim] = uniform(rng, min_b[dim], bounds.max[dim]);
         }
         else
         {
-            max_b[dim] = tg::uniform(rng, bounds.min[dim], min_a[dim]);
-            min_b[dim] = tg::uniform(rng, bounds.min[dim], max_b[dim]);
+            max_b[dim] = uniform(rng, bounds.min[dim], min_a[dim]);
+            min_b[dim] = uniform(rng, bounds.min[dim], max_b[dim]);
         }
 
         auto const aabb_b = tg::aabb3(min_b, max_b);
@@ -73,3 +64,66 @@ TG_FUZZ_TEST(AABB, NonIntersect)
         CHECK(!tg::intersects(aabb_a, aabb_b));
     }
 }
+
+TG_FUZZ_TEST(AABB, SamplingTest)
+{
+    auto const bounds = tg::aabb3(-10, 10);
+    {
+        auto const min_a = uniform(rng, bounds);
+        auto const max_a = uniform(rng, tg::aabb3(min_a, bounds.max));
+
+        auto const min_b = uniform(rng, bounds);
+        auto const max_b = uniform(rng, tg::aabb3(min_b, bounds.max));
+
+        auto const aabb_a = tg::aabb3(min_a, max_a);
+        auto const aabb_b = tg::aabb3(min_b, max_b);
+
+        auto const res = intersection(aabb_a, aabb_b);
+
+        if (res.has_value())
+        {
+            auto const intsct = res.value();
+
+            for (auto i = 0; i < 100; ++i)
+            {
+                auto const v = uniform(rng, bounds);
+
+                if (contains(intsct, v))
+                {
+                    CHECK(contains(aabb_a, v));
+                    CHECK(contains(aabb_b, v));
+                }
+
+                if (contains(aabb_a, v) && contains(aabb_b, v))
+                {
+                    CHECK(contains(intsct, v));
+                }
+
+                if (!contains(aabb_a, v))
+                {
+                    CHECK(!contains(intsct, v));
+                }
+
+                if (!contains(aabb_b, v))
+                {
+                    CHECK(!contains(intsct, v));
+                }
+            }
+        }
+        else
+        {
+            // no intersection
+            for (auto i = 0; i < 50; ++i)
+            {
+                auto const v = uniform(rng, aabb_a);
+                CHECK(!contains(aabb_b, v));
+            }
+
+            for (auto i = 0; i < 50; ++i)
+            {
+                auto const v = uniform(rng, aabb_b);
+                CHECK(!contains(aabb_a, v));
+            }
+        }
+    }
+}