STEP Standards Explained

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Complete STEP File Walkthrough ​

Estimated Time: 30-45 minutes

In this guide, we will provide a complete, line-by-line explanation of an actual STEP file (a simple cube). Through this example, you can gain a concrete understanding of a STEP file's structure.

ðŸ“Ķ Sample File: Simple Cube ​

Below is the complete STEP file for a cube with 10mm sides. You can download the actual file here: cube.step

step
ISO-10303-21;
HEADER;
FILE_DESCRIPTION(('Simple Cube Example'),'2;1');
FILE_NAME('cube.step','2025-12-19T09:00:00',('Author'),('Organization'),'Antigravity Tutorial','Antigravity STEP Writer','Unknown');
FILE_SCHEMA(('AP214_AUTOMOTIVE_DESIGN { 1 0 10303 214 3 1 1 }'));
ENDSEC;
DATA;
/* Product structure */
#10=PRODUCT('Cube','Cube','A simple 10mm cube',(#20));
#20=PRODUCT_CONTEXT('',#30,'mechanical');
#30=APPLICATION_CONTEXT('automotive design');
#40=PRODUCT_DEFINITION_FORMATION('1','First version',#10);
#50=PRODUCT_DEFINITION('design','',#40,#60);
#60=PRODUCT_DEFINITION_CONTEXT('part definition',#30,'design');
#70=PRODUCT_DEFINITION_SHAPE('','',#50);

/* Units and context */
#100=( GEOMETRIC_REPRESENTATION_CONTEXT(3) 
  GLOBAL_UNCERTAINTY_ASSIGNED_CONTEXT((#110)) 
  GLOBAL_UNIT_ASSIGNED_CONTEXT((#120,#130,#140)) 
  REPRESENTATION_CONTEXT('ID1','3D') );
#110=UNCERTAINTY_MEASURE_WITH_UNIT(LENGTH_MEASURE(1.0E-06),#120,'DISTANCE_ACCURACY_VALUE','Maximum model space distance between geometric entities at asserted connectivities');
#120=( LENGTH_UNIT() NAMED_UNIT(*) SI_UNIT(.MILLI.,.METRE.) );
#130=( NAMED_UNIT(*) PLANE_ANGLE_UNIT() SI_UNIT($,.RADIAN.) );
#140=( NAMED_UNIT(*) SI_UNIT($,.STERADIAN.) SOLID_ANGLE_UNIT() );

/* Shape representation */
#200=SHAPE_DEFINITION_REPRESENTATION(#70,#210);
#210=SHAPE_REPRESENTATION('',(#220),#100);
#220=MANIFOLD_SOLID_BREP('Cube',#230);
#230=CLOSED_SHELL('',(#240,#250,#260,#270,#280,#290));

/* Faces (6 faces of the cube) */
/* Bottom face (Z=0) */
#240=ADVANCED_FACE('',(#241),#242,.T.);
#241=FACE_OUTER_BOUND('',#243,.T.);
#243=EDGE_LOOP('',(#244,#245,#246,#247));
#244=ORIENTED_EDGE('',*,*,#300,.T.);
#245=ORIENTED_EDGE('',*,*,#301,.T.);
#246=ORIENTED_EDGE('',*,*,#302,.T.);
#247=ORIENTED_EDGE('',*,*,#303,.T.);
#242=PLANE('',#400);

/* Top face (Z=10) */
#250=ADVANCED_FACE('',(#251),#252,.T.);
#251=FACE_OUTER_BOUND('',#253,.T.);
#253=EDGE_LOOP('',(#254,#255,#256,#257));
#254=ORIENTED_EDGE('',*,*,#304,.T.);
#255=ORIENTED_EDGE('',*,*,#305,.T.);
#256=ORIENTED_EDGE('',*,*,#306,.T.);
#257=ORIENTED_EDGE('',*,*,#307,.T.);
#252=PLANE('',#401);

/* Front face (Y=0) */
#260=ADVANCED_FACE('',(#261),#262,.T.);
#261=FACE_OUTER_BOUND('',#263,.T.);
#263=EDGE_LOOP('',(#264,#265,#266,#267));
#264=ORIENTED_EDGE('',*,*,#300,.T.);
#265=ORIENTED_EDGE('',*,*,#308,.T.);
#266=ORIENTED_EDGE('',*,*,#304,.T.);
#267=ORIENTED_EDGE('',*,*,#309,.F.);
#262=PLANE('',#402);

/* Back face (Y=10) */
#270=ADVANCED_FACE('',(#271),#272,.T.);
#271=FACE_OUTER_BOUND('',#273,.T.);
#273=EDGE_LOOP('',(#274,#275,#276,#277));
#274=ORIENTED_EDGE('',*,*,#302,.T.);
#275=ORIENTED_EDGE('',*,*,#310,.T.);
#276=ORIENTED_EDGE('',*,*,#306,.T.);
#277=ORIENTED_EDGE('',*,*,#311,.F.);
#272=PLANE('',#403);

/* Left face (X=0) */
#280=ADVANCED_FACE('',(#281),#282,.T.);
#281=FACE_OUTER_BOUND('',#283,.T.);
#283=EDGE_LOOP('',(#284,#285,#286,#287));
#284=ORIENTED_EDGE('',*,*,#303,.T.);
#285=ORIENTED_EDGE('',*,*,#311,.T.);
#286=ORIENTED_EDGE('',*,*,#307,.T.);
#287=ORIENTED_EDGE('',*,*,#309,.T.);
#282=PLANE('',#404);

/* Right face (X=10) */
#290=ADVANCED_FACE('',(#291),#292,.T.);
#291=FACE_OUTER_BOUND('',#293,.T.);
#293=EDGE_LOOP('',(#294,#295,#296,#297));
#294=ORIENTED_EDGE('',*,*,#301,.T.);
#295=ORIENTED_EDGE('',*,*,#310,.T.);
#296=ORIENTED_EDGE('',*,*,#305,.T.);
#297=ORIENTED_EDGE('',*,*,#308,.F.);
#292=PLANE('',#405);

/* Edges (12 edges of the cube) */
#300=EDGE_CURVE('',#500,#501,#600,.T.);
#301=EDGE_CURVE('',#501,#502,#601,.T.);
#302=EDGE_CURVE('',#502,#503,#602,.T.);
#303=EDGE_CURVE('',#503,#500,#603,.T.);
#304=EDGE_CURVE('',#504,#505,#604,.T.);
#305=EDGE_CURVE('',#505,#506,#605,.T.);
#306=EDGE_CURVE('',#506,#507,#606,.T.);
#307=EDGE_CURVE('',#507,#504,#607,.T.);
#308=EDGE_CURVE('',#501,#505,#608,.T.);
#309=EDGE_CURVE('',#500,#504,#609,.T.);
#310=EDGE_CURVE('',#502,#506,#610,.T.);
#311=EDGE_CURVE('',#503,#507,#611,.T.);

/* Vertices (8 vertices of the cube) */
#500=VERTEX_POINT('',#700);
#501=VERTEX_POINT('',#701);
#502=VERTEX_POINT('',#702);
#503=VERTEX_POINT('',#703);
#504=VERTEX_POINT('',#704);
#505=VERTEX_POINT('',#705);
#506=VERTEX_POINT('',#706);
#507=VERTEX_POINT('',#707);

/* Edge geometries (lines) */
#600=LINE('',#700,#800);
#601=LINE('',#701,#801);
#602=LINE('',#702,#802);
#603=LINE('',#703,#803);
#604=LINE('',#704,#804);
#605=LINE('',#705,#805);
#606=LINE('',#706,#806);
#607=LINE('',#707,#807);
#608=LINE('',#701,#808);
#609=LINE('',#700,#809);
#610=LINE('',#702,#810);
#611=LINE('',#703,#811);

/* Points (8 corner points) */
#700=CARTESIAN_POINT('',(0.0,0.0,0.0));
#701=CARTESIAN_POINT('',(10.0,0.0,0.0));
#702=CARTESIAN_POINT('',(10.0,10.0,0.0));
#703=CARTESIAN_POINT('',(0.0,10.0,0.0));
#704=CARTESIAN_POINT('',(0.0,0.0,10.0));
#705=CARTESIAN_POINT('',(10.0,0.0,10.0));
#706=CARTESIAN_POINT('',(10.0,10.0,10.0));
#707=CARTESIAN_POINT('',(0.0,10.0,10.0));

/* Direction vectors */
#800=VECTOR('',#900,10.0);
#801=VECTOR('',#901,10.0);
#802=VECTOR('',#902,10.0);
#803=VECTOR('',#903,10.0);
#804=VECTOR('',#904,10.0);
#805=VECTOR('',#905,10.0);
#806=VECTOR('',#906,10.0);
#807=VECTOR('',#907,10.0);
#808=VECTOR('',#908,10.0);
#809=VECTOR('',#909,10.0);
#810=VECTOR('',#910,10.0);
#811=VECTOR('',#911,10.0);

/* Unit direction vectors */
#900=DIRECTION('',(1.0,0.0,0.0));
#901=DIRECTION('',(0.0,1.0,0.0));
#902=DIRECTION('',(-1.0,0.0,0.0));
#903=DIRECTION('',(0.0,-1.0,0.0));
#904=DIRECTION('',(1.0,0.0,0.0));
#905=DIRECTION('',(0.0,1.0,0.0));
#906=DIRECTION('',(-1.0,0.0,0.0));
#907=DIRECTION('',(0.0,-1.0,0.0));
#908=DIRECTION('',(0.0,0.0,1.0));
#909=DIRECTION('',(0.0,0.0,1.0));
#910=DIRECTION('',(0.0,0.0,1.0));
#911=DIRECTION('',(0.0,0.0,1.0));

/* Plane positions */
#400=AXIS2_PLACEMENT_3D('',#700,#1000,#1001);
#401=AXIS2_PLACEMENT_3D('',#704,#1002,#1003);
#402=AXIS2_PLACEMENT_3D('',#700,#1004,#1005);
#403=AXIS2_PLACEMENT_3D('',#703,#1006,#1007);
#404=AXIS2_PLACEMENT_3D('',#700,#1008,#1009);
#405=AXIS2_PLACEMENT_3D('',#701,#1010,#1011);

/* Plane normals and directions */
#1000=DIRECTION('',(0.0,0.0,1.0));
#1001=DIRECTION('',(1.0,0.0,0.0));
#1002=DIRECTION('',(0.0,0.0,-1.0));
#1003=DIRECTION('',(1.0,0.0,0.0));
#1004=DIRECTION('',(0.0,1.0,0.0));
#1005=DIRECTION('',(1.0,0.0,0.0));
#1006=DIRECTION('',(0.0,-1.0,0.0));
#1007=DIRECTION('',(1.0,0.0,0.0));
#1008=DIRECTION('',(1.0,0.0,0.0));
#1009=DIRECTION('',(0.0,1.0,0.0));
#1010=DIRECTION('',(-1.0,0.0,0.0));
#1011=DIRECTION('',(0.0,1.0,0.0));
ENDSEC;
END-ISO-10303-21;

ðŸ’Ą Part 21 Syntax 101 ​

Before we dive into the line-by-line explanation, let's clarify the basic syntax of a STEP file (formally called "ISO 10303-21").

How to read #10=PRODUCT(...); ​

Each line in the DATA section follows this basic pattern: #ID = ENTITY_NAME(Attribute1, Attribute2, ...);

  • # (Hash/Pound): The prefix for an Instance ID. It indicates that a unique ID follows.
  • 10 (The Number): A unique integer identifier for this specific piece of data in this file.
    • Why "10, 20, 30..."?: This is a legacy convention from when files were sometimes edited by hand (similar to BASIC line numbers). It allows for inserting entities later (e.g., #15) without renumbering.
    • Does the number matter?: No. It only needs to be unique within the file. Tools use these to reference other entities (e.g., #10 referencing #20).
  • = (Equals): The Assignment Operator. It means "The entity with ID #10 is defined as...".
  • ; (Semicolon): Every statement in a STEP file must end with a semicolon.

📖 Section-by-Section Explanation ​

1. File Header ​

step
ISO-10303-21;

Meaning: Declares that this file is in the ISO 10303-21 (Part 21) format.

step
HEADER;

Meaning: Start of the HEADER section, which stores file metadata.

step
FILE_DESCRIPTION(('Simple Cube Example'),'2;1');

Meaning: Describes the file.

  • Argument 1: A list of descriptive strings.
  • Argument 2: The implementation level ('2;1' is the standard for Part 21).
step
FILE_NAME('cube.step','2025-12-19T09:00:00',('Author'),('Organization'),'Antigravity Tutorial','Antigravity STEP Writer','Unknown');

Meaning: Information about the file itself.

  • Filename: cube.step
  • Creation Timestamp: 2025-12-19T09:00:00 (ISO 8601 format)
  • Author: Author
  • Organization: Organization
  • Preprocessor: Antigravity Tutorial
  • System: Antigravity STEP Writer
  • Authorization: Unknown
step
FILE_SCHEMA(('AP214_AUTOMOTIVE_DESIGN { 1 0 10303 214 3 1 1 }'));

Meaning: Declaration of the schema (AP) being used.

  • AP214_AUTOMOTIVE_DESIGN: Uses Application Protocol 214.
  • { 1 0 10303 214 3 1 1 }: Version information.

Implementer's Note: This value is checked to determine which AP the parser should use (the first step of parsing).

step
ENDSEC;

Meaning: End of the HEADER section.

2. Data Section: Management Information ​

step
DATA;

Meaning: Start of the DATA section, which contains the actual data (instances of entities).

Product Structure ​

step
#10=PRODUCT('Cube','Cube','A simple 10mm cube',(#20));

Entity: PRODUCT
Meaning: Defines the product itself.

Attributes:

  • id: 'Cube' (Part number/ID)
  • name: 'Cube' (Part name)
  • description: 'A simple 10mm cube' (Description)
  • frame_of_reference: (#20) (List of contexts)

Reference: #20 (PRODUCT_CONTEXT)

step
#20=PRODUCT_CONTEXT('',#30,'mechanical');

Entity: PRODUCT_CONTEXT
Meaning: Context of the product (mechanical, electrical, etc.).

Attributes:

  • name: '' (Empty)
  • frame_of_reference: #30 (APPLICATION_CONTEXT)
  • discipline_type: 'mechanical'
step
#30=APPLICATION_CONTEXT('automotive design');

Entity: APPLICATION_CONTEXT
Meaning: The application domain (e.g., automotive design).

step
#40=PRODUCT_DEFINITION_FORMATION('1','First version',#10);

Entity: PRODUCT_DEFINITION_FORMATION
Meaning: Version management for the product.

Attributes:

  • id: '1'
  • description: 'First version'
  • of_product: #10 (PRODUCT)
step
#50=PRODUCT_DEFINITION('design','',#40,#60);

Entity: PRODUCT_DEFINITION
Meaning: Product definition within a design context.

Attributes:

  • id: 'design'
  • description: ''
  • formation: #40 (PRODUCT_DEFINITION_FORMATION)
  • frame_of_reference: #60 (PRODUCT_DEFINITION_CONTEXT)
step
#60=PRODUCT_DEFINITION_CONTEXT('part definition',#30,'design');

Entity: PRODUCT_DEFINITION_CONTEXT
Meaning: Context for part definition.

step
#70=PRODUCT_DEFINITION_SHAPE('','',#50);

Entity: PRODUCT_DEFINITION_SHAPE
Meaning: The "bridge" between management data and shape data.

Attributes:

  • definition: #50 (PRODUCT_DEFINITION)

Crucial: This is the connection point between management and geometry!

3. Data Section: Units and Context ​

step
#100=( GEOMETRIC_REPRESENTATION_CONTEXT(3) 
  GLOBAL_UNCERTAINTY_ASSIGNED_CONTEXT((#110)) 
  GLOBAL_UNIT_ASSIGNED_CONTEXT((#120,#130,#140)) 
  REPRESENTATION_CONTEXT('ID1','3D') );

Entity: Complex type (defines 4 entities simultaneously)
Meaning: Context for geometric representation.

Breakdown:

  • GEOMETRIC_REPRESENTATION_CONTEXT(3): Three-dimensional.
  • GLOBAL_UNCERTAINTY_ASSIGNED_CONTEXT((#110)): Precision settings.
  • GLOBAL_UNIT_ASSIGNED_CONTEXT((#120,#130,#140)): Unit settings.
  • REPRESENTATION_CONTEXT('ID1','3D'): Identifier.
step
#110=UNCERTAINTY_MEASURE_WITH_UNIT(LENGTH_MEASURE(1.0E-06),#120,'DISTANCE_ACCURACY_VALUE','...');

Entity: UNCERTAINTY_MEASURE_WITH_UNIT
Meaning: Definition of geometric precision.

Value: 1.0E-06 mm (0.001 Ξm) = 1 nm (very high precision).

step
#120=( LENGTH_UNIT() NAMED_UNIT(*) SI_UNIT(.MILLI.,.METRE.) );

Entity: Complex type
Meaning: Unit of length.

Interpretation: .MILLI.,.METRE. = mm (millimeters).

Implementer's Note: Always check this value to calculate your unit conversion factors!

How Units Flow Through the File:

Key Points:

  • Units are defined once (e.g., #120 defines millimeters)
  • Units are assigned to GEOMETRIC_REPRESENTATION_CONTEXT (#100)
  • All geometry in SHAPE_REPRESENTATION (#210) inherits these units
  • All coordinate values (like CARTESIAN_POINT) are interpreted using these units
  • Critical: Always read the unit definition before interpreting coordinates!
step
#130=( NAMED_UNIT(*) PLANE_ANGLE_UNIT() SI_UNIT($,.RADIAN.) );

Entity: Plane angle unit.
Value: Radians.

step
#140=( NAMED_UNIT(*) SI_UNIT($,.STERADIAN.) SOLID_ANGLE_UNIT() );

Entity: Solid angle unit.
Value: Steradians.

4. Data Section: Shape Representation ​

step
#200=SHAPE_DEFINITION_REPRESENTATION(#70,#210);

Entity: SHAPE_DEFINITION_REPRESENTATION
Meaning: Links PRODUCT_DEFINITION_SHAPE (#70) to SHAPE_REPRESENTATION (#210).

step
#210=SHAPE_REPRESENTATION('',(#220),#100);

Entity: SHAPE_REPRESENTATION
Meaning: Top-level container for geometry.

Attributes:

  • name: ''
  • items: (#220) (List of geometry elements)
  • context_of_items: #100 (GEOMETRIC_REPRESENTATION_CONTEXT)
step
#220=MANIFOLD_SOLID_BREP('Cube',#230);

Entity: MANIFOLD_SOLID_BREP
Meaning: A closed 3D solid.

Attributes:

  • name: 'Cube'
  • outer: #230 (CLOSED_SHELL)
step
#230=CLOSED_SHELL('',(#240,#250,#260,#270,#280,#290));

Entity: CLOSED_SHELL
Meaning: A collection of closed faces (the 6 faces of the cube).

Attributes:

  • cfs_faces: List of 6 faces.

5. Data Section: Faces ​

Since all faces have the same structure, we'll explain one (the bottom face) in detail.

step
#240=ADVANCED_FACE('',(#241),#242,.T.);

Entity: ADVANCED_FACE
Meaning: Defines a face.

Attributes:

  • name: ''
  • bounds: (#241) (Face boundaries)
  • face_geometry: #242 (Geometry of the face: PLANE)
  • same_sense: .T. (Normal direction matches the face geometry)
step
#241=FACE_OUTER_BOUND('',#243,.T.);

Entity: FACE_OUTER_BOUND
Meaning: Outer boundary of the face (inner boundaries exist if there are holes).

Attributes:

  • bound: #243 (EDGE_LOOP)
  • orientation: .T. (Positive orientation)
step
#243=EDGE_LOOP('',(#244,#245,#246,#247));

Entity: EDGE_LOOP
Meaning: A loop of edges (forming a rectangle with 4 edges).

Attributes:

  • edge_list: List of 4 ORIENTED_EDGE instances.
step
#244=ORIENTED_EDGE('',*,*,#300,.T.);

Entity: ORIENTED_EDGE
Meaning: A directional edge.

Attributes:

  • edge_element: #300 (EDGE_CURVE)
  • orientation: .T. (Use the edge direction as-is)

Note: If .F., use the edge in reverse.

step
#242=PLANE('',#400);

Entity: PLANE
Meaning: A plane surface.

Attributes:

  • position: #400 (AXIS2_PLACEMENT_3D: Plane location and orientation)

6. Data Section: Edges ​

step
#300=EDGE_CURVE('',#500,#501,#600,.T.);

Entity: EDGE_CURVE
Meaning: A curved edge (a straight line in this case).

Attributes:

  • edge_start: #500 (VERTEX_POINT: Start vertex)
  • edge_end: #501 (VERTEX_POINT: End vertex)
  • edge_geometry: #600 (LINE: The geometry of the edge)
  • same_sense: .T. (Edge direction matches geometry direction)

7. Data Section: Vertices ​

step
#500=VERTEX_POINT('',#700);

Entity: VERTEX_POINT
Meaning: A vertex (a point in topology).

Attributes:

  • vertex_geometry: #700 (CARTESIAN_POINT)

8. Data Section: Geometry (Lines & Points) ​

step
#600=LINE('',#700,#800);

Entity: LINE
Meaning: An infinite straight line (geometry for an edge).

Attributes:

  • pnt: #700 (CARTESIAN_POINT: A point on the line)
  • dir: #800 (VECTOR: Direction vector)
step
#700=CARTESIAN_POINT('',(0.0,0.0,0.0));

Entity: CARTESIAN_POINT
Meaning: A point in 3D Cartesian space.

Attributes:

  • coordinates: (0.0, 0.0, 0.0) (The origin)

Unit: mm (defined in #120).

step
#800=VECTOR('',#900,10.0);

Entity: VECTOR
Meaning: A vector.

Attributes:

  • orientation: #900 (DIRECTION: Unit direction vector)
  • magnitude: 10.0 (Length)
step
#900=DIRECTION('',(1.0,0.0,0.0));

Entity: DIRECTION
Meaning: A direction (unit vector).

Attributes:

  • direction_ratios: (1.0, 0.0, 0.0) (X-axis direction)

9. Data Section: Plane Placement ​

step
#400=AXIS2_PLACEMENT_3D('',#700,#1000,#1001);

Entity: AXIS2_PLACEMENT_3D
Meaning: Position and orientation in 3D space (coordinate system).

Attributes:

  • location: #700 (CARTESIAN_POINT: Origin)
  • axis: #1000 (DIRECTION: Z-axis direction = Plane normal)
  • ref_direction: #1001 (DIRECTION: X-axis direction)
step
ENDSEC;
END-ISO-10303-21;

Meaning: End of the DATA section and the end of the file.

🔍 Data Flow Diagram ​

Visualizing how the cube data is structured:

ðŸ’Ą Tips for Implementers ​

Parsing Considerations ​

  1. Two-Pass Processing is Mandatory: Forward references exist (e.g., #10 referencing a later #20).
  2. Confirm Units: Apply the unit defined in #120 (mm) to all coordinates.
  3. Reference Resolution: Manage #numbers using a hash map.

Why Two-Pass Processing is Required:

Example of Forward Reference Problem:

step
#10 = PRODUCT('Part1', 'Part1', '', (#20));  ← References #20 (not defined yet!)
#20 = PRODUCT_CONTEXT('', #30, 'mechanical'); ← References #30 (not defined yet!)
#30 = APPLICATION_CONTEXT('automotive design');

Solution: First pass stores all instances, second pass resolves all references.

Common Validation Checks ​

python
# Check vertex count for a cube
vertices = find_all_by_type(step_file, 'VERTEX_POINT')
assert len(vertices) == 8, f"Expected 8 vertices, found {len(vertices)}"

# Check edge count
edges = find_all_by_type(step_file, 'EDGE_CURVE')
assert len(edges) == 12, f"Expected 12 edges, found {len(edges)}"

# Check face count
faces = find_all_by_type(step_file, 'ADVANCED_FACE')
assert len(faces) == 6, f"Expected 6 faces, found {len(faces)}"

# Euler's Polyhedral Formula: V - E + F = 2
V, E, F = len(vertices), len(edges), len(faces)
assert V - E + F == 2, f"Euler check failed: {V} - {E} + {F} != 2"

ðŸŽŊ Experiment: Try Modifying This File ​

Experiment 1: Change the Size ​

Double all coordinates:

step
#700=CARTESIAN_POINT('',(0.0,0.0,0.0));  → No change
#701=CARTESIAN_POINT('',(10.0,0.0,0.0)); → (20.0,0.0,0.0)
#702=CARTESIAN_POINT('',(10.0,10.0,0.0)); → (20.0,20.0,0.0)
...

Experiment 2: Change the Units ​

Change from mm to meters:

step
#120=( LENGTH_UNIT() NAMED_UNIT(*) SI_UNIT(.MILLI.,.METRE.) );

↓

step
#120=( LENGTH_UNIT() NAMED_UNIT(*) SI_UNIT($,.METRE.) );

Result: 10mm cube → 10m cube (1000x larger).

Experiment 3: Add Color ​

Add red color to the bottom face (#240):

step
#2000=STYLED_ITEM('',(#2010),#240);
#2010=PRESENTATION_STYLE_ASSIGNMENT((#2020));
#2020=SURFACE_STYLE_USAGE(.BOTH.,#2030);
#2030=SURFACE_SIDE_STYLE('',(#2040));
#2040=SURFACE_STYLE_RENDERING(#2050,.MATTE.);
#2050=COLOUR_RGB('Red',1.0,0.0,0.0);

📚 Next Steps ​

Once you understand this file:

  1. Data Model Map - Understand more complex hierarchies.
  2. Common Pitfalls - Implementation warnings.
  3. Actual Parser Implementation: Try parsing this file using Python.

📚 Next Steps ​

Back to README

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