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.

// 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;
    extension[0]='\0';
 
    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
 
    HC_Open_Segment_By_Key(m_ModelKey);
 
    // 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
 
    HC_Open_Segment("");
    if (streq(extension,"xmt_txt") || streq(extension,"x_t"))
    {
        PK_PART_receive_o_t options;
        PK_ERROR_code_t result;
        PK_PART_receive_o_m(options);

        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;
 
    HC_Close_Segment();
    HC_Close_Segment();
 
    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

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