Format ilk olarak 1990'lı yıllarda yalnızca 3D içeriğin değil aynı zamanda toleranslar ve malzemeler gibi endüstriyel kullanıma özgü ek verilerin standartlaştırılması amacıyla ortaya çıktı. ISO-10303-21 standardı olarak bilinen STEP dosyaları standardı, ek özelliklerin etkinleştirilmesi için yıllar içinde revize edilmiştir.
STEP dosyasındaki 3 boyutlu veriler, yüzlerden, kenarlardan ve diğer geometrik verilerden oluşan şekillerin bir kombinasyonu kullanılarak metin biçiminde temsil edilir. Belirtildiği gibi, STEP formatı 3D model değişimi için bir standart olacak şekilde tasarlanmıştır; bu, CAD ve 3D modelleme uygulamalarının yanı sıra dosya dönüştürme yazılımı arasında da yaygın bir desteğe sahip olduğu anlamına gelir.
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);
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035#23=TOROIDAL_SURFACE($,#12211,0.1771875,0.0759375);
036#24=(
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065REPRESENTATION_ITEM($)
066SURFACE()
067);
Metin tabanlı format nedeniyle, karmaşık 3D verileri formata kaydederken STEP dosyaları çok büyük olabilir. STEP dosyalarının düzenleme yazılımına yüklenmesi de biraz zaman alabilir, bu nedenle lütfen bu dosyaları düzenlerken ek süre tanıyın.
