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• [[en:infra-convert:user:terms#Drawing sheet]]\\ | • [[en:infra-convert:user:terms#Drawing sheet]]\\ | ||
• [[en:infra-convert:user:terms#Drawing data format]]\\ | • [[en:infra-convert:user:terms#Drawing data format]]\\ | ||
+ | **F**\\ | ||
+ | • [[en:infra-convert:user:terms#Font]]\\ | ||
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• [[en:infra-convert:user:terms#Measurement (sizes-)]]\\ | • [[en:infra-convert:user:terms#Measurement (sizes-)]]\\ | ||
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==== Drawing data format ==== | ==== Drawing data format ==== | ||
- | Different data formats have been established for the exchange of →[[en:infra-convert:user:terms#Zeichnung (Technische)|Technical drawings]]. All exchange formats transport at least the graphic information of a drawing printed on paper. Vector formats and specially developed drawing formats in particular also store information, which facilitate automated reading by computer programs. | + | Various data formats have been established for the digital exchange of →[[en:infra-convert:user:terms#Drawing (technical)|technical drawings]]. Each data format transports at least the graphic information of a drawing printed on paper. In addition, vector formats and especially specially developed drawing data formats store information that facilitates automated readout by computer programs. |
- | A drawing is put together based on standards from graphic elements linear in shape as well as text elements. These standards are now widely recognized on an international level. The meaning is conveyed to the reader from the arrangement of the individual elements to each other. However, implementing this type of interpretation work in terms of software is complex and only possible to a very limited extent. Drawing formats therefore offer an additional means to store such information. | + | Basically, a technical drawing is constructed according to largely internationally defined standards from linear graphic elements as well as text elements. The reader derives the meaning from the arrangement of the elements in relation to each other. However, this kind of interpretation work can only be implemented by software to a very limited extent. For this reason, additional information is stored in drawing data formats, which indicates to a software that the elements belong together and what they mean. |
- | We have to initially differentiate between raster-bound and vector-based formats. | + | The suitability of different data formats for automated interpretation can be generalized as follows: |
+ | |||
+ | {{ :en:infra-convert:user:terms:uebersicht_zeichnungsdatenformate.png?nolink&600 |}} | ||
+ | |||
+ | > In #@IC_HTML@#, a CAD exchange format is the minimum requirement for fully automatic feature recognition. | ||
<WRAP group> | <WRAP group> | ||
- | <WRAP column half> | + | <WRAP column 40%> |
- | **Raster graphics** such as JPG, PNG, BMP, TIFF and GIF only transport graphical information addressed to the reader. Software can only retrieve the stored information by referring to the pixels (//Pattern recognition//). The technologies that are actually implemented focus on the text recognition, the so-called //Optical Character Recognition// (OCR). They have, at least in the area of technical drawings, a recognition rate of around 50%. | + | **Raster graphic formats** only transport the graphic information addressed to the reader. Software can only retrieve the stored information ("pattern recognition") by relating the pixels to one another. Actually used technologies concentrate on text recognition, the so-called "Optical Character Recognition" (OCR). They have a recognition rate of about 50 to 70 %, at least in the area of technical drawings. |
- | The adjacent illustration shows the structure of a raster graphic as an example. | + | > In #@IC_HTML@#, drawings in raster graphic format can be stamped manually using the quick input dialog.\\ \\ **See**\\ Functions > Characteristics > [[en:infra-convert:user:functions:ballooning_man|Manually stamp]] |
</WRAP> | </WRAP> | ||
- | <WRAP column half> | + | <WRAP column 55%> |
- | {{ :en:infra-convert:user:terms:rastergrafik.png?direct&300 |}} | + | {{ :en:infra-convert:user:terms:rastergrafikformat.png?nolink&450 |}} |
</WRAP> | </WRAP> | ||
</WRAP> | </WRAP> | ||
- | **Vector formats**, in contrast, store graphic elements as unique, mathematically depicted graphic primitives (basic geometric elements such as straight lines, circular arcs and splines as well as surfaces such as circles, polygons and spline surfaces) as well as texts using character encoding. The //Portable Document Format// (PDF) supports vector-based data storage, for example. | + | Vector graphic formats, on the other hand, store graphic elements as unique, mathematically described graphic primitives. The latter mean basic geometric elements such as straight lines, arcs, and splines, as well as surfaces such as circles, polygons, and spline surfaces. Texts are stored either as polylines or with the help of character encoding. |
+ | |||
+ | > In #@IC_HTML@#, character-coded texts are a prerequisite for automatic feature recognition. | ||
<WRAP group> | <WRAP group> | ||
- | <WRAP column half> | + | <WRAP column 40%> |
- | **Drawing formats** also combine vector elements to groups or blocks that belong together and store group and drawing-related metadata in doing so. Views, hatchings, dimensional entries etc. remain identifiable as such. The //Drawing Interchange File Format// (DXF) released by Autodesk has become established as a global, neutral industry standard. Autodesk's own DWG format (from "__d__ra__w__in__g__") is also supported by the majority of CAD systems. #@IC_HTML@# also supports the IGES format (//Initial Graphics Exchange Specification)//. | + | The PDF format (PDF = "Portable Document Format") supports raster-based and vector-based data storage. Coded text characters are stored in text fields, such as "⌀ 20" in the adjacent example. |
- | The adjacent example illustrates vector elements as they can be displayed using a viewer based on a drawing format. The colors code the line widths. The monochrome display (text and graphic elements in one color) is preferred in #@IC_HTML@#. | + | > In #@IC_HTML@#, drawings in raster-based PDF format can be stamped manually using the quick input dialog. Drawings in vector-based PDF format can be stamped automatically* if the characters are coded.\\ \\ * A pro license is required.\\ \\ **See**\\ Functions > Characteristics > [[en:infra-convert:user:functions:ballooning_man|Manually stamp]]\\ Functions > Characteristics > [[en:infra-convert:user:functions:ballooning|Automatic stamping]] |
</WRAP> | </WRAP> | ||
- | <WRAP column half> | + | <WRAP column 55%> |
- | {{ :en:infra-convert:user:terms:zeichnungsformat.png?direct&300 |}} | + | {{ :en:infra-convert:user:terms:pdf-format.png?nolink&450 |}} |
</WRAP> | </WRAP> | ||
</WRAP> | </WRAP> | ||
+ | |||
+ | <WRAP group> | ||
+ | <WRAP column 40%> | ||
+ | |||
+ | With the PDF format it should be noted that not all CAD systems export all characters encoded - usually special characters -, but as geometric elements. The suitability for automated readability is reduced accordingly. | ||
+ | |||
+ | </WRAP> | ||
+ | <WRAP column 55%> | ||
+ | |||
+ | {{ :en:infra-convert:user:terms:pdf-format_schriften_als_geometrien.png?nolink&450 |}} | ||
+ | |||
+ | </WRAP> | ||
+ | </WRAP> | ||
+ | |||
+ | \\ | ||
+ | |||
+ | <WRAP group> | ||
+ | <WRAP column 40%> | ||
+ | |||
+ | **CAD formats** store data largely based on design elements. Views, hatches, dimension entries etc. remain recognizable as such for a processing software, such as the dimension entry for the diameter 20 of the cylinder in the adjacent example. | ||
+ | |||
+ | > In #@IC_HTML@# drawings can be processed in DXF format ("Drawing Interchange File Format", worldwide and neutral industry standard), in DWG format (Autodesk's own format, also supported by most CAD systems) or in IGES format* ("Initial Graphics Exchange Specification").\\ \\ * A license for the IGES module is required.\\ \\ **Note** The multicolored representation of native CAD drawing formats has the background that the colors encode line widths. In the early days of CAD, different line widths could only be displayed poorly on the screen using the technology of the time. An ink pen was assigned to a color on the plotter. An assignment table for line widths ("pentable") is usually not exported to the usual exchange formats. For better legibility, #@IC_HTML@# therefore displays drawings in monochrome ("black on white") as standard. | ||
+ | |||
+ | </WRAP> | ||
+ | <WRAP column 55%> | ||
+ | |||
+ | {{ :en:infra-convert:user:terms:cad-format.png?nolink&450 |}} | ||
+ | |||
+ | </WRAP> | ||
+ | </WRAP> | ||
+ | |||
+ | \\ | ||
+ | |||
+ | ---- | ||
+ | |||
+ | \\ | ||
+ | |||
+ | ==== Font ==== | ||
+ | |||
+ | Non-graphic information is specified in technical drawings using characters. Characters can be letters, numbers, diacritics, punctuation marks, and additional graphic symbols. Due to their frequent repetition, they are grouped into a stock, the character set. In electronic data processing, characters are uniquely identified by coding in a character set. Numerous standards exist worldwide for character coding. "ASCII" is an example of a very small set, "Unicode" an example of a very large set to which characters are continuously added. A digital character set is called a **font**. A font file usually contains a character set with a uniform graphic design. | ||
+ | |||
+ | {{ :en:infra-convert:user:terms:schriftartdatei.png?nolink&700 |}} | ||
+ | |||
+ | In addition to the purely visual representation of characters, the unambiguous definition of characters is important for the automatic analysis of technical drawings. PDF files are generally used to displaying characters correctly. This is because the character definitions used are saved in the file. This is (unfortunately) different with the CAD exchange formats DXF, DWG and IGES. In them only the references to characters are stored in font files. The font files are therefore required for correct display. | ||
+ | |||
+ | > **Significance for #@IC_HTML@#** Fonts are protected by copyright. In most cases, the rights of use are only granted for a fee. The number of fonts used by CAD systems is immensely high. Supplying these fonts would disproportionately increase the cost of #@IC_HTML@# licenses. For this reason, #@IC_HTML@# replaces fonts not installed on the computer with visually similar fonts when loading drawing files. If this is the case, a note message is issued. | ||
+ | |||
+ | {{ :en:infra-convert:user:terms:schriftarten_austauschformate.png?nolink&700 |}} | ||
\\ | \\ |