From 8a6a1fc2df5022607835ccdef32783f0d02562b0 Mon Sep 17 00:00:00 2001
From: RichardTea <31507749+RichardTea@users.noreply.github.com>
Date: Tue, 1 Mar 2022 12:12:07 +0000
Subject: [PATCH] Update AI_TEXTURE_TYPE_MAX

Must be equal to the largest aiTextureType_XXX enum
---
 include/assimp/material.h      |  2 +-
 test/unit/utMaterialSystem.cpp | 60 ++++++++++++++++++++++++++++++++++
 2 files changed, 61 insertions(+), 1 deletion(-)

diff --git a/include/assimp/material.h b/include/assimp/material.h
index 416dbc4a8..2ccd83763 100644
--- a/include/assimp/material.h
+++ b/include/assimp/material.h
@@ -331,7 +331,7 @@ enum aiTextureType {
 #endif
 };
 
-#define AI_TEXTURE_TYPE_MAX aiTextureType_UNKNOWN
+#define AI_TEXTURE_TYPE_MAX aiTextureType_TRANSMISSION
 
 // -------------------------------------------------------------------------------
 // Get a string for a given aiTextureType
diff --git a/test/unit/utMaterialSystem.cpp b/test/unit/utMaterialSystem.cpp
index 7b4560443..3016f8881 100644
--- a/test/unit/utMaterialSystem.cpp
+++ b/test/unit/utMaterialSystem.cpp
@@ -135,3 +135,63 @@ TEST_F(MaterialSystemTest, testMaterialNameAccess) {
 
     delete mat;
 }
+
+// ------------------------------------------------------------------------------------------------
+#if defined(_MSC_VER)
+// Refuse to compile on Windows if any enum values are not explicitly handled in the switch
+// TODO: Move this into assimp/Compiler as a macro and add clang/gcc versions so other code can use it
+__pragma(warning(push));
+__pragma(warning(error : 4061)); // enumerator 'identifier' in switch of enum 'enumeration' is not explicitly handled by a case label
+__pragma(warning(error : 4062)); // enumerator 'identifier' in switch of enum 'enumeration' is not handled
+#endif
+
+TEST_F(MaterialSystemTest, testMaterialTextureTypeEnum) {
+    // Verify that AI_TEXTURE_TYPE_MAX equals the largest 'real' value in the enum
+
+    int32_t maxTextureType = 0;
+    static constexpr int32_t bigNumber = 255;
+    EXPECT_GT(bigNumber, AI_TEXTURE_TYPE_MAX) << "AI_TEXTURE_TYPE_MAX too large for valid enum test, increase bigNumber";
+
+    // Loop until a value larger than any enum
+    for (int32_t i = 0; i < bigNumber; ++i) {
+        aiTextureType texType = static_cast<aiTextureType>(i);
+        switch (texType) {
+        default: break;
+#ifndef SWIG
+        case _aiTextureType_Force32Bit: break;
+#endif
+            // All the real values
+        case aiTextureType_NONE:
+        case aiTextureType_DIFFUSE:
+        case aiTextureType_SPECULAR:
+        case aiTextureType_AMBIENT:
+        case aiTextureType_EMISSIVE:
+        case aiTextureType_HEIGHT:
+        case aiTextureType_NORMALS:
+        case aiTextureType_SHININESS:
+        case aiTextureType_OPACITY:
+        case aiTextureType_DISPLACEMENT:
+        case aiTextureType_LIGHTMAP:
+        case aiTextureType_REFLECTION:
+        case aiTextureType_BASE_COLOR:
+        case aiTextureType_NORMAL_CAMERA:
+        case aiTextureType_EMISSION_COLOR:
+        case aiTextureType_METALNESS:
+        case aiTextureType_DIFFUSE_ROUGHNESS:
+        case aiTextureType_AMBIENT_OCCLUSION:
+        case aiTextureType_SHEEN:
+        case aiTextureType_CLEARCOAT:
+        case aiTextureType_TRANSMISSION:
+        case aiTextureType_UNKNOWN:
+            if (i > maxTextureType)
+                maxTextureType = i;
+            break;
+        }
+    }
+
+    EXPECT_EQ(maxTextureType, AI_TEXTURE_TYPE_MAX) << "AI_TEXTURE_TYPE_MAX macro must be equal to the largest valid aiTextureType_XXX";
+}
+
+#if defined(_MSC_VER)
+__pragma (warning(pop))
+#endif