Overview

The STEP Ship Schema Library merges the definitions from AP215, AP216, AP218, and AP203 into a single EXPRESS schema and generated C++ class library. This allows applications to use C++ classes and easily read and write files from any of these APs.

• Merged schema in a browsable form, as well as the EXPRESS source listing.
• Working set file.

A installer for the STEP Merged Ship Schema Library is available at the URL below. This installer is for use with ST-Developer v12 on the Win32 platform. Contact us if you have ST-Developer v12 and need a version for a different platform.

ftp://ftp.steptools.com/pub/stdev/stpship_12_0_win32.msi

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Using the Library

The stpship class library is installed as shown below:

• Include File: stp_schema.h
• Include Path: $(ROSE_INCLUDE)/stpship
• Library Path: $(ROSE_LIB) with stpship.lib or -lstpship
• Class List

The classes belong to the "step_ship_schema" schema so we have added functions that query the AP that a file was read as and control the AP that a file identifies itself as when writing. You must call stpship_init() at the start of your application to initialize handling of STEP files with the merged schema.

void stpship_init();

Example:

#include <stp_schema.h>

int main(int argc, char* argv[])
{
    stp_schema_force_load();
    stpship_init();

    // body of program
}

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Writing Files

When you create a new file, call the stpship_put_schema() function to identify the schema that should be written in the P21 header. If you do not call this, the file will identify its schema as "STEP_SHIP_SCHEMA", which no other application will recognize.

These schema control functions use the StpShipSchemaType enum to identify the APs. The stpship_schema_none value is used to indicate a design has just been created and not assigned an AP.

enum StpShipSchemaType {
    stpship_schema_none,  // new file, no schema set
    stpship_schema_ap203, 
    stpship_schema_ap215, 
    stpship_schema_ap216, 
    stpship_schema_ap218,
    stpship_schema_other, 
};


void stpship_put_schema (
    RoseDesign * design, 
    StpShipSchemaType schema_code
    );

The sample program below creates a design containing a single cartesian point and writes it out using each of the possible schemas:

#include <stp_schema.h>

void main()
{
    stp_schema_force_load();
    stpship_init();

    RoseDesign *d = new RoseDesign ("foo");

    stp_cartesian_point * p = pnewIn(d) stp_cartesian_point;

    // no proper AP, just step_ship_schema
    d-> saveAs ("test_default.stp");

    stpship_put_schema (d, stpship_schema_ap203);
    d-> saveAs ("test_ap203.stp");

    stpship_put_schema (d, stpship_schema_ap215);
    d-> saveAs ("test_ap215.stp");

    stpship_put_schema (d, stpship_schema_ap216);
    d-> saveAs ("test_ap216.stp");

    stpship_put_schema (d, stpship_schema_ap218);
    d-> saveAs ("test_ap218.stp");
}

The complete set of types are available to you, so it is possible to create files containing instances that are not appropriate for an AP, such as a non_manifold_surface_shape_representation in an AP203 file. To help, we have annotated the EXPRESS to indicate which APs support each definition.

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Reading Files

When reading files, use the stpship_get_schema() function to query the schema that a file was read as. If the type is "other", the stpship_get_schema_name can be used to get schema name.

StpShipSchemaType stpship_get_schema (
    RoseDesign * design
    );

char * stpship_get_schema_name (
    RoseDesign * design
    );

The code below reads the files written by the previous example and prints out some identifying schema information:

#include <stp_schema.h>

void print_info (RoseDesign *d)
{
    printf ("==> schemaname: %s\n", stpship_get_schema_name (d));

    switch (stpship_get_schema (d)) {
    case stpship_schema_none:	printf ("==> no schema set\n");  break;
    case stpship_schema_ap203: 	printf ("==> AP203 file\n");  break;
    case stpship_schema_ap215: 	printf ("==> AP215 file\n");  break;
    case stpship_schema_ap216: 	printf ("==> AP216 file\n");  break;
    case stpship_schema_ap218:	printf ("==> AP218 file\n");  break;
    case stpship_schema_other:	printf ("==> Other type of file\n");  break;
    }
}

void main()
{
    stp_schema_force_load();
    stpship_init();

    printf ("Using null pointer\n");
    print_info (0);

    printf ("Using new design\n");
    print_info (new RoseDesign ("foo"));

    print_info (ROSE.findDesign ("test_default.stp"));
    print_info (ROSE.findDesign ("test_ap203.stp"));
    print_info (ROSE.findDesign ("test_ap215.stp"));
    print_info (ROSE.findDesign ("test_ap216.stp"));
    print_info (ROSE.findDesign ("test_ap218.stp"));
}

The code will print the following output:

Using null pointer
==> schemaname: step_ship_schema
==> no schema set
Using new design
==> schemaname: step_ship_schema
==> no schema set
Reading: .\test_default.stp
==> schemaname: STEP_SHIP_SCHEMA
==> Other type of file
Reading: .\test_ap203.stp
==> schemaname: CONFIG_CONTROL_DESIGN
==> AP203 file
Reading: .\test_ap215.stp
==> schemaname: SHIP_ARRANGEMENT_SCHEMA
==> AP215 file
Reading: .\test_ap216.stp
==> schemaname: SHIP_MOULDED_FORM_SCHEMA
==> AP216 file
Reading: .\test_ap218.stp
==> schemaname: SHIP_STRUCTURES_SCHEMA
==> AP218 file