Reading Parasolid Files

To read a Parasolid file, call HP_Read_Xmt_File. This parses the specified Parasolid file, populates the Parasolid modeling kernel with its contents, and then maps the model to a corresponding HOOPS segment tree hierarchy that includes all geometry and attributes. Example:

// an application specific read function; HSolidModel is derived
// from the HBaseModel MVO class
int HSolidModel::Read(const char * FileName)
        unsigned int i;
        char extension[120];
        bool success = true;

        HC_Parse_String(FileName, ".", -1, extension); // make it lower case

        for (i = 0; i < strlen(extension); i++)
                extension[i] = (char) tolower(extension[i]); // read the file into the model object's model segment


        // read each file into its own subsegment of the main model segment so that
        // we can easily apply transformations to different parts that might be read
        // into the same model object; currently not supported in MVO, but could be
        // added in the future. This is also required so that when we do segment
        // level deletion later on, we don't delete the model_keysegment

        if (streq(extension,"xmt_txt") || streq(extension,"x_t"))
                PK_PART_receive_o_t options;
                PK_ERROR_code_t result;

                options.transmit_format = PK_transmit_format_text_c; // read an XT file
                result = HP_Read_Xmt_File(FileName, GetPartition(), 0, 0, &options);

                if (result  0)
                        success = false;

        } else
                success = false;


        return success;

Controlling Tessellation

You can control facet tessellation as an import argument. In HP_Read_Xmt_File, use the face_tessellation_level parameter to specify tessellation. Valid options are as follows:

  • “Lowest”

  • “Low”

  • “Medium”

  • “High”

  • “Highest”

  • “Custom”

“Custom” is the default, which means the developer is responsible for setting all the tessellation options himself. You can also set tessellation options in HP_Render_Entity and HP_Render_Entities. Examples of the effect of the tessellation are shown below:


“Custom” tessellation


“Medium” tessellation


“Highest” tessellation