- GetImporterInstanceList reads ASSIMP_ENABLE_DEV_IMPORTERS env var. Development importers are enabled if the env var is set and is not equal to the literal string "0".
- X3D importer will not be registered unless ASSIMP_ENABLE_DEV_IMPORTERS is set; addresses #3647.
TODO: If this change is incorporated, it should be documented.
NOTE: Effective git branch structure is a better solution. This is an alternate for #3825.
The search for a matching importer had a few issues, see #3791. There were two different mechanisms to determine whether an importer accepts a specific file extension:
1. `aiImporterDesc::mFileExtensions`, which was forwarded to the UI via `BaseImporter::GetExtensionList()`.
2. `BaseImporter::CanRead()` when called with `checkSig == false`, which determines whether to actually use that importer.
Both were redundant and got out of sync repeatedly. I removed 2. completely and replaced it with 1., thereby syncing UI/import and shortening all `BaseImporter::CanRead()` implementations.
Further bugfixes:
- fixed glTF2 importer throwing exceptions when checking whether it can load a file
- removed `BaseImporter::SimpleExtensionCheck()` because it is no longer used and had a bug with case sensitivity
Since the `checkSig` parameter in `BaseImporter::CanRead()` is now useless, it can be removed completely. I’m not sure if this would break ABI compatiblity, so I’ll submit it with a later pull request.
Textures were being double deleted after a merge scene because the
texture array wasn't being properly deleted at the end of merging.
Furthermore, the texture array was being sized to the number of
materials instead of the number of textures.
std::string s(""); s = ""; calls the copy constructor, which in turn calls strlen(), … assigning a default-constructed string generates fewer instructions and is therefore preferred.
With C++11 uniform initialization, you’d simply write s = { } instead.
