After a long thought we decide to develop CAD engine ourselves to avoid a dependence on 3rd party. Now, we are busy with selection module as the mathematical way is not convenient. So, we are trying to use OpenGL features.
We tried all month to move to CAD engine Open Cascade. Unfortunately, it seems that it is not possible as we want to have a direct access to the key features. So, we are still thinking if we need to use a third-side engine to accelerate our development.
We developed an initial interface for the program. Currently, we are working on CAD an mesh generator implementation. On CAD side, the basic functions, such as point, line, arc, circle, curve are implemented. We are working to integrate the surfaces. On Mesh generation side we are testing the general tetra mesh generation.