From SBL6/SBL601.TXT :
[Overview]
The Sega Basic Library (SBL) is a low-level library which can be applied to many uses. This library enabled developers the flexibility they needed to create their own customized applications. However, past versions of SBL were not helpful for the development of 3D graphics-based software.
The Sega Game Library (SGL) is a high-level library which can be used mainly for 3D graphics applications. However, depending on the application, the developers are forced to deal with many of its restrictions.
The objective of SBL6.0 is to integrate the positive aspects of both libraries. SBL6.0 provides developers the flexibility of customizing their applications as with the old SBL, along with taking advantage of the benefits provided by the expanded features ported from SGL.
It is possible to combine the features from SBL and SGL.* By skillfully utilizing SBL and SGL according to the needs of the application, the developer can develop software quickly and efficiently. For example, although basic hardware-level control functions were provided by previous versions of SBL, the user had to bear the overhead of coming up with a efficient polygon rendering engine. In contrast, while SGL has a powerful polygon 3D engine, there are weaknesses in its support for the Saturn's scroll functions due to the its original design implementation.
SBL6.0 provides a development environment with high efficiency and flexibility in order to compensate for the deficiencies found in both SBL and SGL.
* Keep in mind that limitations will inevitably appear when SBL and SGL are combined.