Bug/evaluate matrix4x4 access (#5936)

* Add test for 3x3 matrices and 4x4 matrix access

test/unit/AssimpAPITest_aiMatrix3x3.cpp

@@ -5,8 +5,6 @@ Open Asset Import Library (assimp)
 
 Copyright (c) 2006-2024, assimp team
 
-
-
 All rights reserved.
 
 Redistribution and use of this software in source and binary forms,
@@ -42,6 +40,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 #include "UnitTestPCH.h"
 #include "MathTest.h"
+#include <array>
 
 using namespace Assimp;
 
@@ -158,3 +157,18 @@ TEST_F(AssimpAPITest_aiMatrix3x3, aiMatrix3FromToTest) {
     aiMatrix3FromTo(&result_c, &from, &to);
     EXPECT_EQ(result_cpp, result_c);
 }
+
+TEST_F(AssimpAPITest_aiMatrix3x3, operatorTest) {
+    std::array<ai_real, 9> value = { 1, 2, 3, 4, 5, 6, 7, 8,9};
+    result_cpp = aiMatrix3x3( value[0], value[1], value[2], value[3],
+                              value[4], value[5], value[6], value[7],
+                              value[8]);
+    size_t idx=0;
+    for (unsigned int i = 0; i < 3; ++i) {
+       for (unsigned int j = 0; j < 3; ++j) {
+            ai_real curValue = result_cpp[i][j];
+            EXPECT_EQ(curValue, value[idx]);
+            idx++;
+       }
+    }
+}