From 56a4c0783b10a2e0da71f985c8a96c59fa48871a Mon Sep 17 00:00:00 2001
From: Stephen Seo <seo.disparate@gmail.com>
Date: Mon, 6 May 2024 14:11:41 +0900
Subject: [PATCH] Impl Sphere/GenericBox to AABB

---
 src/sc_sacd.cpp | 55 +++++++++++++++++++++++++++++++++++++++++++++++++
 src/sc_sacd.h   |  4 ++++
 src/test.cpp    | 48 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 107 insertions(+)

diff --git a/src/sc_sacd.cpp b/src/sc_sacd.cpp
index d6dc6a4..070f4e8 100644
--- a/src/sc_sacd.cpp
+++ b/src/sc_sacd.cpp
@@ -572,3 +572,58 @@ SC_SACD_Vec3 SC_SACD_Closest_Point(const SC_SACD_Vec3 *pos,
 float SC_SACD_Vec3_Length(const SC_SACD_Vec3 vec) {
   return std::sqrt(SC_SACD_Dot_Product(vec, vec));
 }
+
+SC_SACD_AABB_Box SC_SACD_Sphere_To_AABB(const SC_SACD_Sphere s) {
+  SC_SACD_AABB_Box aabb{};
+
+  aabb.x = s.x;
+  aabb.y = s.y;
+  aabb.z = s.z;
+
+  aabb.width = s.radius * 2.0F;
+  aabb.height = s.radius * 2.0F;
+  aabb.depth = s.radius * 2.0F;
+
+  return aabb;
+}
+
+SC_SACD_AABB_Box SC_SACD_Generic_Box_To_AABB(const SC_SACD_Generic_Box s) {
+  SC_SACD_AABB_Box aabb{};
+
+  auto corners = SC_SACD_Get_Box_Corners(&s);
+
+  SC_SACD_Vec3 min{INFINITY, INFINITY, INFINITY};
+  SC_SACD_Vec3 max{-INFINITY, -INFINITY, -INFINITY};
+
+  for (const auto &corner : corners) {
+    if (corner.x < min.x) {
+      min.x = corner.x;
+    }
+    if (corner.y < min.y) {
+      min.y = corner.y;
+    }
+    if (corner.z < min.z) {
+      min.z = corner.z;
+    }
+
+    if (corner.x > max.x) {
+      max.x = corner.x;
+    }
+    if (corner.y > max.y) {
+      max.y = corner.y;
+    }
+    if (corner.z > max.z) {
+      max.z = corner.z;
+    }
+  }
+
+  aabb.width = max.x - min.x;
+  aabb.height = max.y - min.y;
+  aabb.depth = max.z - min.z;
+
+  aabb.x = min.x + aabb.width / 2.0F;
+  aabb.y = min.y + aabb.height / 2.0F;
+  aabb.z = min.z + aabb.depth / 2.0F;
+
+  return aabb;
+}
diff --git a/src/sc_sacd.h b/src/sc_sacd.h
index e0bddb5..b18dcef 100644
--- a/src/sc_sacd.h
+++ b/src/sc_sacd.h
@@ -133,6 +133,10 @@ SC_SACD_EXPORT SC_SACD_Vec3 SC_SACD_Closest_Point(const SC_SACD_Vec3 *pos,
 
 SC_SACD_EXPORT float SC_SACD_Vec3_Length(const SC_SACD_Vec3 vec);
 
+SC_SACD_EXPORT SC_SACD_AABB_Box SC_SACD_Sphere_To_AABB(const SC_SACD_Sphere s);
+SC_SACD_EXPORT SC_SACD_AABB_Box
+SC_SACD_Generic_Box_To_AABB(const SC_SACD_Generic_Box s);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/test.cpp b/src/test.cpp
index a759639..83b08ea 100644
--- a/src/test.cpp
+++ b/src/test.cpp
@@ -633,6 +633,54 @@ int main() {
     CHECK_TRUE(SC_SACD_Generic_Box_Collision(&a, &b));
   }
 
+  // Test Sphere/GenericBox to AABB.
+  {
+    SC_SACD_Sphere s{10.0F, 10.0F, 10.0F, 5.0F};
+
+    SC_SACD_AABB_Box aabb = SC_SACD_Sphere_To_AABB(s);
+    CHECK_FLOAT(aabb.x, s.x);
+    CHECK_FLOAT(aabb.y, s.y);
+    CHECK_FLOAT(aabb.z, s.z);
+    CHECK_FLOAT(aabb.width, s.radius * 2.0F);
+    CHECK_FLOAT(aabb.height, s.radius * 2.0F);
+    CHECK_FLOAT(aabb.depth, s.radius * 2.0F);
+
+    SC_SACD_Generic_Box box = SC_SACD_Generic_Box_Default();
+    box.x = 20.0F;
+    box.y = 20.0F;
+    box.z = 20.0F;
+
+    aabb = SC_SACD_Generic_Box_To_AABB(box);
+    CHECK_FLOAT(aabb.x, box.x);
+    CHECK_FLOAT(aabb.y, box.y);
+    CHECK_FLOAT(aabb.z, box.z);
+    CHECK_FLOAT(aabb.width, box.width);
+    CHECK_FLOAT(aabb.height, box.height);
+    CHECK_FLOAT(aabb.depth, box.depth);
+
+    box.transform =
+        SC_SACD_Rotation_Mat4_ZAxis(std::numbers::pi_v<float> / 4.0F);
+
+    aabb = SC_SACD_Generic_Box_To_AABB(box);
+    CHECK_FLOAT(aabb.x, box.x);
+    CHECK_FLOAT(aabb.y, box.y);
+    CHECK_FLOAT(aabb.z, box.z);
+    CHECK_FLOAT(aabb.width, std::sqrt(2.0F) * 2.0F);
+    CHECK_FLOAT(aabb.height, std::sqrt(2.0F) * 2.0F);
+    CHECK_FLOAT(aabb.depth, box.depth);
+
+    auto translate = SC_SACD_Translate_Mat4(-5.0F, -4.0F, 1.0F);
+    box.transform = SC_SACD_Mat4_Mult(&translate, &box.transform);
+
+    aabb = SC_SACD_Generic_Box_To_AABB(box);
+    CHECK_FLOAT(aabb.x, box.x - 5.0F);
+    CHECK_FLOAT(aabb.y, box.y - 4.0F);
+    CHECK_FLOAT(aabb.z, box.z + 1.0F);
+    CHECK_FLOAT(aabb.width, std::sqrt(2.0F) * 2.0F);
+    CHECK_FLOAT(aabb.height, std::sqrt(2.0F) * 2.0F);
+    CHECK_FLOAT(aabb.depth, box.depth);
+  }
+
   std::cout << "Checks checked: " << checks_checked << '\n'
             << "Checks passed:  " << checks_passed << '\n';