Expose aiGetEmbeddedTexture to C-API (#5382)

Co-authored-by: Kim Kulling <[email protected]>

code/Common/Assimp.cpp

@@ -512,6 +512,11 @@ void aiGetMemoryRequirements(const C_STRUCT aiScene *pIn,
     ASSIMP_END_EXCEPTION_REGION(void);
 }
 
+// ------------------------------------------------------------------------------------------------
+ASSIMP_API const C_STRUCT aiTexture *aiGetEmbeddedTexture(const C_STRUCT aiScene *pIn, const char *filename) {
+    return pIn->GetEmbeddedTexture(filename);
+}
+
 // ------------------------------------------------------------------------------------------------
 ASSIMP_API aiPropertyStore *aiCreatePropertyStore(void) {
     return reinterpret_cast<aiPropertyStore *>(new PropertyMap());
@@ -1268,7 +1273,6 @@ ASSIMP_API void aiQuaternionInterpolate(
     aiQuaternion::Interpolate(*dst, *start, *end, factor);
 }
 
-
 // stb_image is a lightweight image loader. It is shared by:
 //  - M3D import
 //  - PBRT export
@@ -1279,21 +1283,21 @@ ASSIMP_API void aiQuaternionInterpolate(
 #define ASSIMP_HAS_M3D ((!ASSIMP_BUILD_NO_EXPORT && !ASSIMP_BUILD_NO_M3D_EXPORTER) || !ASSIMP_BUILD_NO_M3D_IMPORTER)
 
 #ifndef STB_USE_HUNTER
-#   if ASSIMP_HAS_PBRT_EXPORT
-#       define ASSIMP_NEEDS_STB_IMAGE 1
-#   elif ASSIMP_HAS_M3D
-#       define ASSIMP_NEEDS_STB_IMAGE 1
-#       define STBI_ONLY_PNG
-#   endif
+#if ASSIMP_HAS_PBRT_EXPORT
+#define ASSIMP_NEEDS_STB_IMAGE 1
+#elif ASSIMP_HAS_M3D
+#define ASSIMP_NEEDS_STB_IMAGE 1
+#define STBI_ONLY_PNG
+#endif
 #endif
 
 // Ensure all symbols are linked correctly
 #if ASSIMP_NEEDS_STB_IMAGE
-    // Share stb_image's PNG loader with other importers/exporters instead of bringing our own copy.
-#   define STBI_ONLY_PNG
-#   ifdef ASSIMP_USE_STB_IMAGE_STATIC
-#       define STB_IMAGE_STATIC
-#   endif
-#   define STB_IMAGE_IMPLEMENTATION
-#   include "Common/StbCommon.h"
+// Share stb_image's PNG loader with other importers/exporters instead of bringing our own copy.
+#define STBI_ONLY_PNG
+#ifdef ASSIMP_USE_STB_IMAGE_STATIC
+#define STB_IMAGE_STATIC
+#endif
+#define STB_IMAGE_IMPLEMENTATION
+#include "Common/StbCommon.h"
 #endif

include/assimp/cimport.h

@@ -58,6 +58,7 @@ extern "C" {
 #endif
 
 struct aiScene;
+struct aiTexture;
 struct aiFileIO;
 
 typedef void (*aiLogStreamCallback)(const char * /* message */, char * /* user */);
@@ -373,6 +374,13 @@ ASSIMP_API void aiGetMemoryRequirements(
         const C_STRUCT aiScene *pIn,
         C_STRUCT aiMemoryInfo *in);
 
+// --------------------------------------------------------------------------------
+/** Returns an embedded texture, or nullptr.
+ * @param pIn Input asset.
+ * @param filename Texture path extracted from aiGetMaterialString.
+ */
+ASSIMP_API const C_STRUCT aiTexture *aiGetEmbeddedTexture(const C_STRUCT aiScene *pIn, const char *filename);
+
 // --------------------------------------------------------------------------------
 /** Create an empty property store. Property stores are used to collect import
  *  settings.