drawings sdk依赖kernel sdk
kernel sdk核心模块包括：
- TD_Alloc — Memory allocation（内存分配）
- TD_Root — Core functionality（核心功能）
- TD_DbRoot — Common database functionality（通用数据库功能）
- TD_Ge — Geometry classes (OdGe*)（几何类）
- TD_Gi — Entity vectorization classes (OdGi*)（实体矢量化类）
- TD_Gs — Graphical system classes (OdGs*)（图形化系统类）
- TD_SpatialIndex — Spatial indexing support (OdSi*)（空间索引支持）
drawings sdk的模块包括：
-
TD_DbCore — Implements the core .dwg database functionality（实现核心的dwg数据库功能）
-
TD_Db — Provides the functionality to initialize and uninitialize the
core Drawings SDK runtime environment implemented in the following
modules:-
TD_DbIO.tx - Extension that implements file read-write components for .dwg, .dxf, and .dxb formats and some other file-related operation APIs. It can be loaded optionally as a TD_DbIO extension application.
-
TD_DbEntities.tx - Extension that implements the built-in entity set.
It can be loaded optionally as a TD_DbEntities extension application. -
ISM.tx - Extension that implements the raster image entity
-
WipeOut.tx - Extension that implements the WipeOut entity
-
RText.tx - Extension that implements the RText entity
-
ATEXT.tx - Extension that implements the arc-aligned text entity
-
SCENEOE.tx - Extension that implements a set of scene definition and rendering setting components
-
ACCAMERA.tx - Extension that implements the camera entity
-
AcMPolygonObj15.tx - Extension that implements the multi-polygon
entity. -
TG_Db — .dgn files support functionality
-
参考：https://docs.opendesign.com/td/tdrawings_libraries.html
