IGES Project (IPRJ) Subsystem

The IPRJ subsystem provides the ability to project IGES entities from a specified IGES drawing or view entity into the specified model. Currently only the 404 form 0 and the 410 form 0 are supported. The projection of an IGES drawing entity will project the drawing's model space geometry and drawing space entities through the drawing's associated views into the specified model. The projection of the IGES view entity will project and clip all IGES model space geometry visible in the view to the destination model. The destination model does not have to be empty, but the units between the model that MDA_PTR is defined in and the destination model are assumed to the same.

The subsystem can be called on an entity level. The main interface bindings are:

PDX_MSGT iprj_Project404( long option,
                          IEVM_VAL_RESULTS *ievm_val_results,
                          MDA_PTR db_404, int dst_model,
                          double origin[2], void *results)
PDX_MSGT iprj_Project410( long option,
                          IEVM_VAL_RESULTS *ievm_val_results,
                          MDA_PTR db_410, int dst_model,
                          double origin[2], void *results)

The following options may be used for the iprj_Project404 interface:

The following option may be used for the iprj_Project410 interface:

The IEVM_VAL_RESULTS structure is the structure that is returned from entity validation (IEVM), this will allow only valid entities to be projected to a drawing or view. The MDA_PTR pointer will be either a drawing or view db_ptr. The dst_model model is an allocated model that the projected model is to be placed. The destination model does not have to be empty, but the model space units are assumed to be the same. The origin array represents the new origin for the drawing. This is useful for projecting multiple drawings into one file. The results structure returned has not been implimented yet.

The IPRJ subsystem uses 4 tolerances: MODEL_SPACE_PNT_COIN_TOL, PNT_PROJ_TOL, ZERO_TOL and MODEL_LINEAR_APPROX_TOL. Note: MODEL_LINEAR_APPROX_TOL needs to be set in the model that is to be projected. (see gdx_InitTolerances, iprj_intro)

During the projection of the IGES drawing or view it maybe necessary to create extra entities with different types and forms because of the entity's orientation in a specific view. For instance, if a circle was to be displayed in three different view, such as a Top, Front and Isometric view, and the Top view defines the circle, the Front view would contain a line and the Isometric view would contain an ellipse. The resulting model would contain three IGES entities from the one that originally existed in the IGES file. The list below contains the mapping of the IGES entities.