Here is my first attempt to create a framework on DirectX 7 (Immediate Mode) that began around 2003/02.
The programming language was Pascal in Delphi IDE; the source code is available but dirty. because it was my first try and I was a beginner.
The simple framework has 2 parts, one is an editor called Maker and the other is a Viewer.
The Maker has 4 view ports with full-screen display capabilities. but the object creation method was in the wrong way! The sample was just a try to write down an editor, not a renderer 😀
The viewer was a simple test for lighting, fog, render states, and some features on DirectX 7. Viewers use a text file to load a scene from the Objects folder. the text file contains a list of file names and a simple position vector ( just like this: filename1.omf|x|y|z ). Each file contains vectors in binary format and all textures inside.

Download: Framework-DX7 source