O formato surgiu pela primeira vez na década de 1990 com o objetivo de padronizar não apenas o conteúdo 3D, mas também dados adicionais específicos para uso industrial, como tolerâncias e materiais. Conhecido como padrão ISO-10303-21, o padrão para arquivos STEP foi revisado ao longo dos anos para permitir recursos adicionais.
Os dados 3D no arquivo STEP são representados em formato de texto usando uma combinação de formas compostas de faces, arestas e outros dados geométricos. Conforme mencionado, o formato STEP foi projetado para ser um padrão para troca de modelos 3D, o que significa que tem amplo suporte entre aplicativos de modelagem CAD e 3D, bem como software de conversão de arquivos.
000ISO-10303-21;
001HEADER;
002/* Generated by software containing ST-Developer
003 * from STEP Tools, Inc. (www.steptools.com)
004 */
005
006FILE_DESCRIPTION(
007/* description */ (''),
008/* implementation_level */ '2;1');
009
010FILE_NAME(
011/* name */ 'c5.stp',
012/* time_stamp */ '2024-02-05T06:35:35+00:00',
013/* author */ (''),
014/* organization */ (''),
015
016/* authorisation */ '');
017
018FILE_SCHEMA (('AUTOMOTIVE_DESIGN { 1 0 10303 214 3 1 1 }'));
019ENDSEC;
020
021DATA;
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024#12=ORIENTED_CLOSED_SHELL($,*,#11433,.F.);
025#13=ORIENTED_CLOSED_SHELL($,*,#11434,.F.);
026#14=ORIENTED_CLOSED_SHELL($,*,#11435,.F.);
027#15=CONICAL_SURFACE($,#11713,0.59315625,0.759762754875772);
028#16=CONICAL_SURFACE($,#11720,0.59315625,0.759762754875772);
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035#23=TOROIDAL_SURFACE($,#12211,0.1771875,0.0759375);
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066SURFACE()
067);
Devido ao formato baseado em texto, os arquivos STEP podem ficar muito grandes ao salvar dados 3D complexos no formato. Os arquivos STEP também podem levar algum tempo para serem carregados no software de edição, portanto, reserve um tempo adicional ao editar esses arquivos.
