From 3ba2dbed57a201f50152591a09fc24084afd8fa0 Mon Sep 17 00:00:00 2001
From: Razakhel <romain.milbert@gmail.com>
Date: Sat, 2 Sep 2023 15:34:30 +0200
Subject: [PATCH] [Tests/Data/Mesh] Added a basic Mesh unit test

- This checks the Mesh's basic behavior

- Computing tangents on an empty mesh is now a no-op
---
 include/RaZ/Data/Mesh.hpp   |  2 +-
 src/RaZ/Data/Mesh.cpp       |  3 +++
 tests/src/RaZ/Data/Mesh.cpp | 30 ++++++++++++++++++++++++++++++
 3 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/include/RaZ/Data/Mesh.hpp b/include/RaZ/Data/Mesh.hpp
index 806ed9c2..be04fda7 100644
--- a/include/RaZ/Data/Mesh.hpp
+++ b/include/RaZ/Data/Mesh.hpp
@@ -72,7 +72,7 @@ class Mesh : public Component {
   void createIcosphere(const Sphere& sphere, uint32_t subdivCount);
 
   std::vector<Submesh> m_submeshes {};
-  AABB m_boundingBox = AABB(Vec3f(), Vec3f());
+  AABB m_boundingBox = AABB(Vec3f(0.f), Vec3f(0.f));
 };
 
 } // namespace Raz
diff --git a/src/RaZ/Data/Mesh.cpp b/src/RaZ/Data/Mesh.cpp
index c23d8bb0..b417846f 100644
--- a/src/RaZ/Data/Mesh.cpp
+++ b/src/RaZ/Data/Mesh.cpp
@@ -250,6 +250,9 @@ const AABB& Mesh::computeBoundingBox() {
 }
 
 void Mesh::computeTangents() {
+  if (m_submeshes.empty())
+    return;
+
   Threading::parallelize(m_submeshes, [] (const auto& range) noexcept {
     for (Submesh& submesh : range) {
       for (std::size_t i = 0; i < submesh.getTriangleIndexCount(); i += 3) {
diff --git a/tests/src/RaZ/Data/Mesh.cpp b/tests/src/RaZ/Data/Mesh.cpp
index 0002af7b..f3729ca7 100644
--- a/tests/src/RaZ/Data/Mesh.cpp
+++ b/tests/src/RaZ/Data/Mesh.cpp
@@ -2,6 +2,36 @@
 
 #include "RaZ/Data/Mesh.hpp"
 
+TEST_CASE("Mesh basic") {
+  Raz::Mesh mesh;
+  CHECK(mesh.getSubmeshes().empty());
+  CHECK(mesh.getBoundingBox() == Raz::AABB(Raz::Vec3f(0.f), Raz::Vec3f(0.f)));
+  CHECK(mesh.recoverVertexCount() == 0);
+  CHECK(mesh.recoverTriangleCount() == 0);
+
+  CHECK_NOTHROW(mesh.computeTangents()); // Attempting to compute tangents for an empty mesh does nothing
+
+  const Raz::AABB& boundingBox = mesh.computeBoundingBox();
+  CHECK(boundingBox == Raz::AABB(Raz::Vec3f(std::numeric_limits<float>::max()), Raz::Vec3f(std::numeric_limits<float>::lowest())));
+  CHECK(boundingBox == mesh.getBoundingBox());
+
+  Raz::Submesh& submesh = mesh.addSubmesh();
+  CHECK(mesh.getSubmeshes().size() == 1);
+
+  submesh.getVertices() = {
+    Raz::Vertex{ Raz::Vec3f(-1.f) },
+    Raz::Vertex{ Raz::Vec3f(0.f) },
+    Raz::Vertex{ Raz::Vec3f(1.f) }
+  };
+  submesh.getTriangleIndices() = { 0, 1, 2 };
+  CHECK(mesh.recoverVertexCount() == 3);
+  CHECK(mesh.recoverTriangleCount() == 1);
+
+  mesh.computeBoundingBox();
+  CHECK(boundingBox == Raz::AABB(Raz::Vec3f(-1.f), Raz::Vec3f(1.f)));
+  CHECK(boundingBox == mesh.getBoundingBox());
+}
+
 TEST_CASE("Mesh plane") {
   const Raz::Plane plane(1.5f, Raz::Axis::Y);