Object Drawing/Data Base-technologies (OD/DB) in CAD
Perhaps, the following has been already described, named and analyzed. Appreciate the information about it. Any criticism is welcome, including that of the terms used.
OD/DB overview
There is almost an infinite number of custom CAD applications, branded "vertical" CAD applications’ modules with common principles, objectives and purpose.
The terms «OD/DB», «OD/DB-technologies» are used hereinafter as the general representation of such solutions.
OD/DB, OD/DB-technologies – software, applications, solutions, methods for drawing with the possibility of object selection from the menus (lists, classifications, toolbars, palettes, etc.), with automatic activation of proper drawing parameters, with the identification of graphical elements as proper object types and with the possibility of its characteristics values input, edit.
OD/DB – Object Drawing/Data Base:
- OD, Object Drawing – object drawing, drawing with the automatic assignment of graphical elements with proper graphical properties, graphical elements identification as objects, and
- DB, Data Base – database of these objects and its characteristics, databases and information systems models creation.
OD/DB can be implemented in different ways and by different tools, with different completeness, consistency and adequacy degree. Therefore, the term "technologies" is used.
Examples of object menus in some real custom OD/DB-applications.
To date, the presence of common features in such solutions was not fixed or has not become widespread notion. Thus the common approaches and criteria and common, universal solutions have not been developed. This is largely due to the initial CAD purpose, mainly as the drawing tools, i.e. the tools to create graphical models. Largely due to the narrow specialization of custom OD/DB-solutions and branded "vertical" solutions. At the same time, for example, Map 3D (“vertical” solution for AutoCAD) Feature classes tool (Object classes) can be used in principle for drawing in any subject area. Alternatively, it is said by piping engineers that the possibilities of Electrical (another "vertical" solution for AutoCAD) suit them well. But some of such custom solutions’ creators realize its potential versatility.
Generally, OD/DB – any software and technological solutions of main tasks:
- drawing with simultaneous graphical properties and parameters assigning,
- identification of graphical elements as objects,
- objects characteristics definition.
The main goals achieved with OD/DB:
- speed up and ease the drawing,
- standardization of objects’ drawing representation, drawing standards correspondence and propagation,
- essential improvement of drawings quality,
- additional capabilities of data manipulation,
- creation of new type of output – drawings-models with better object information completeness and more suitable for software analysis, data preparation for vertical applications and external information systems.
Object drawing and the database of the drawn objects and their characteristics are linked not randomly and not arbitrary. This is actually the same task viewed from different angles – the task of creation drawings/models with better drawing/modeling object compatibility.
Consistent and complete solution of the object drawing task and consistent and complete solution of graphical elements identification as objects and objects’ characteristics determination task have three common key intersection.
First, both object drawing and objects and their characteristics database require the same – object types definitions. The appearance of object types definition with complete solution of any of the foregoing tasks makes it possible to describe all other object information – from their graphical properties to their characteristics parameters and other object types parameters.
Second, object types and their characteristics definition naturally includes the definition of graphical elements properties and settings used to display these object types. Availability of drawing tools to create graphical elements determined with certain object types (object drawing) is obvious.
Third, the best and consistent solution of the object drawing task involves graphical elements assignment with non-graphical IDs of the object types. These help to carry out the most complete and unambiguous audits of graphic elements’ graphical properties validity, provide additional valuable opportunities to manipulate graphical data. In other words, complete solution of the object drawing task involves the use of database possibilities.
OD/DB tasks solution can be actually carried out not only with varying degrees of completeness and consistency, but also with a variety of combinations of different solution methods.
In particular, drawing with the given set of graphical properties can be made through the menu of object lists, classified object lists, through palettes, panels with buttons, etc. Identification with objects can be carried out by means of layers for each object type, unique sets of graphical properties for each object type, using CAD built-in extended data, by means of external databases. Definition of object characteristics can be made with text attributes of elements or even plain text elements, using CAD built-in “extended” data, by means of external databases.
For example, there are Tool Palettes in AutoCAD since 2004, which allow building objects menus –necessary object lists for drawing directly with proper primitives and graphical properties desired. This CAD addition is obviously refers to OD/DB-technologies but solves only one task – drawing with proper parameters. Or, for example, CAD is known to use the possibilities of external databases. Or, for example, many CAD have built-in abilities to add descriptive data to graphical elements. The use of external databases and internal databases creation generally allows to store and describe the characteristics of object IDs, i.e. allows solving these OD/DB tasks.
That is, CAD themselves contain or may contain OD/DB possibilities and gradually the number and completeness of these possibilities may be increased.
The emergence and existence OD/DB for CAD is caused by the fact that CAD themselves are not originally and mostly designed to solve these tasks or they solve them incompletely or this is too demanding. Accordingly, it is impossible to reach the OD/DB goals completely and technologically with basic CAD features.
Therefore OD/DB, OD/DB-technologies are almost coeval with CAD themselves. There are hundreds, perhaps thousands of custom applications implementing OD/DB-technologies. For all or most of the drawing subject areas custom OD/DB applications were created and constantly are created – depending on the country, company, organization, CAD version, etc. Almost every branded "vertical" CAD application contains OD/DB for its subject area. In some cases, one "vertical" application may contain two or more different OD/DB solutions.
Furthermore, almost simultaneously with CAD (and sometimes even before they appear!) the independent specialized programs for thematic drawing were developed directly on the basis of OD/DB – for architects, various engineering areas, mapping, etc. The OD/DB principles were often laid in the architecture of such programs and, unlike CAD, there may be no possibility to draw simple graphical elements (line, circle, etc.). It may be possible only as a graphical representation of the object of particular type – that is the continuity of graphics and its object identification.
Drawing standards & subject area objects definition
To solve object drawing task (OD/...) in CAD, the definition of object types and all the required drawing parameters for each object type must be created: graphical primitive types, graphical properties, the parameters of drawing process and generated elements. To solve object identification and their characteristics determination tasks (.../DB) in CAD, the definitions of all object types are also required: object types IDs, characteristics, parameters and their possible values.
Full description of object types and drawing parameters of certain subject area compose the drawing standard definition.
Often used capabilities of existing OD/DB-solutions shown black, rarely used or not used capabilities are shown blue. In most cases, the drawing standards definitions come down to objects definition.
Using full drawing standards definitions provides a number of additional features that are not available in CAD and help to automate many processes and produce many actions programmatically.
Often used capabilities of existing OD/DB-solutions shown black, rarely used or not used capabilities are shown blue. In most OD/DB implementations only a minority of capabilities is used.
Drawing standards definitions (or only that of objects) can be implemented in different ways and with different user convenience. The methods of drawing standards definitions can be divided into definitions in external files and internal program definitions. The definitions in the form of external text files allow the users to create and edit them directly with simple text editors. Internal program definitions are available for editing only by programmers, but such programs can have built-in plugins for object definitions editing by users.
The creation of drawing standards definitions is the most time-consuming and responsible process for users in OD/DB-technologies. For many subject areas the number of object types may run to hundreds or even thousands. A number of well-established drawing or layout standards might be used in one subject area as well as there might be an urgent need to create and edit drawing standards definitions depending on customer requirements. Therefore, drawing standards definitions must be as transparent as possible, sufficiently complete and require minimum efforts when creating and editing for the successful use of OD/DB. Furthermore, it is necessary to be able to describe a number of different drawing standards.
Despite the complexity and the responsibility of drawing standards definitions (object definitions) creation, these definitions can be quickly accumulated and can be shared among any number of users. In this case, the goal of subject area common drawing and layout standards distribution can be achieved quite quickly. The latter can greatly facilitate the data exchange between different organizations, companies, users and can facilitate and accelerate drawings creation of the required drawing standards.
The purposes of OD/DB
OD/DB compared to conventional CAD capabilities allow to speed up drawing, to improve drawings quality, it extends the capabilities of data manipulation, enables data analysis, allows object characteristics description in a form convenient for software analysis.
Drawing speed up with OD/DB is achieved by:
- automated set of all necessary drawing settings on the basis of drawing standards definitions,
- objects drawing directly with necessary commands, with all necessary properties and parameters as per objects definitions,
- additional data manipulation capabilities,
- full drawing checks for compliance with the selected standards,
- automated drawing fixes in accordance with the selected standards.
When using drawing standards definitions, OD/DB provide the support of all necessary CAD settings and parameters, drawings "on-the-fly". This saves users’ time for CAD and drawings setup, including the creation of necessary layers, layouts, loading of all the necessary drawing resources – block libraries, line types, text styles, hatches, etc.
When drawing one element with common CAD tools it takes three to fifteen settings to set the desired properties and plot options. In case of complex drawings with many object types, manual set of the desired object properties is sufficiently complex and time-consuming. OD/DB drawing with all necessary parameters and properties already set as per object definitions, release users from the labor costs for manual setting of these parameters and properties.
In sum, setting default options "on the fly" and drawing objects already with the desired properties provide the creation of the drawings with high level of compliance with the selected standards. This significantly reduces the complexity of drawings checks and corrections thanks to OD/DB.
Additional OD/DB data manipulation capabilities – additional capabilities of object selection, assignment graphical elements with necessary properties, substitution of graphical properties, etc. as per object descriptions. These advanced capabilities allow themselves to speed up and facilitate drawing creation.
Integral drawing checks for compliance with the selected standards and drawing fixes with OD/DB allow speeding up drawings’ customer preparation.
From general considerations, from the experience of OD/DB-solutions usage it is possible to estimate weightily the potential complexity reduction and speed growth due to full and proper OD/DB implementations to the value of 20% to 50-100%.
At the same time OD/DB help to achieve the highest quality of the created drawings automatically, i.e. OD/DB provide full correspondence between drawings and the selected drawing or layout standard. Using typical CAD tools, such quality can only be achieved with meticulous manual checks.
OD/DB provide the creation of more informative graphic models than conventional CAD-drawings, i.e. provide the creation of models pointed at objects and its characteristics software analysis. This allows the creation of CAD models designed for information systems, “large” databases and vertical CAD applications.
The development of such models is achieved in OD/DB by the identification of graphical elements as objects of the desired type, by determining values of the objects’ characteristics.
Identification of graphical elements as objects can be accomplished by using layers (one layer for one object type) and unique sets of graphical properties for each object type. If all subject area objects can be represented as units (block, cell, etc.), IDs may be the names of the units. Object identification can be done by adding non-graphical data with object types designation (object type names, codes) to the graphic elements. These non-graphical data can be implemented with the help of built-in CAD non-graphical data definition capabilities or by means of external databases.
Objects characteristics definition can also be done in different ways and with different completeness – not completely with text attributes or even with text elements, and completely – with internal CAD descriptive data, using external databases tools.
Integral OD/DB implementations are possible with the help of native CAD additional data or by means of external databases as full-fledged objects characteristics’ definition can be done in general only by these means. Furthermore, the use of external or internal databases allows identifying graphical elements as objects using the non-graphical tokens. That gives additional possibilities to manipulate data as compared to merely graphic characteristics usage. Again, the use of non-graphical object type IDs gives the users almost complete object graphical representation independence, allows changing graphical representation methods quickly.
In order to determine the values of object characteristics a set of capabilities may be implemented for automation of the values input, edit, view, search, etc.
To provide data transfer (other formats, other CAD systems, information systems, for the use of other software) the capabilities of data export/import are preferable.
OD/DB CAD implementation
OD/DB is implemented with software additions to CAD. One of the OD/DB features in CAD – the possibility to use them simultaneously, parallel to conventional CAD tools. The optional usage gives a greater degree of freedom for the users. In other words, the users can always draw not only with objects from object menu, but also with native CAD commands and primitives. OD/DB-objects can be mostly manipulated with native CAD tools along with this additional software.
Complete OD/DB solutions in custom applications are rare; almost every OD/DB solution is highly specialized –limited in their capabilities in accordance with the drawing subjects. Most of full OD/DB implementations in branded vertical CAD solutions are also highly specialized and not universal.
In addition to incompleteness and specialization of the available OD/DB solutions, most of the custom solutions do not allow the creation and edition of drawing object definitions by users. Thus, almost every custom OD/DB solution is not universal, can’t be applied to different drawing subject areas.
Most CAD-companies use OD/DB-technologies fully or partially in its vertical applications. To date, there are no braded complete and universal OD/DB solutions for CAD.
In general, the situation with CAD OD/DB-technologies is paradoxical, and was paradoxical almost with the appearance of CAD themselves. OD/DB-technologies are in demand, have noticeable advantages and specific benefits, have countless incarnations as custom applications, used in most "vertical" solutions. Nonetheless, there are no branded complete and universal CAD OD/DB-solutions (vertical applications of one CAD may contain different OD/DB implementations, of different completeness, made with different tools, etc.). For basic CAD versions, OD/DB capabilities are scarcely used.
Another CAD OD/DB paradox is that user demand for not only graphical but also analytical models grows and will only increase. CAD-companies basically respond with constant expansion of their assortment and the capabilities of vertical applications. The companies develop or buy the most powerful object modeling tools with high-quality object properties imitations, realistic interactions modeling, dynamics modeling, etc. But basic CAD capabilities remain unmodified since the beginning of their appearance. That is, CAD basis – drawing, creation of drawings as graphical models generally remains at their original already archaic level. While basic CAD consists the majority of users.
Successful, i.e. complete, convenient, universal OD/DB CAD implementation could be such a variant of drawings creation and CAD workflow modernization, giving the users additional significant opportunities – acceleration, quality improvement, models creation for better computer analysis. But there is no information about such plans of CAD-companies.
Therefore, it can be assumed with high probability that sooner or later, there will be high-quality custom OD/DB-applications for basic CAD, which can claim universality, completeness of features, usability and the presence of convenient ways to define drawing standards.
On the one hand, the appearance of quality custom OD/DB-applications for CAD support CAD common interest and can add CAD users. On the other hand, a number of such custom OD/DB-solutions describing drawing standards differently can appear simultaneously or nearly simultaneously. If first such decisions are successful there will inevitably appear many new ones. Many different drawing standards definition structures will reduce the effect of OD/DB usage and distribution – such definitions will be created and distributed more slowly, it will be more difficult to find the relevant already made standard definition for concrete OD/DB-solution. Variously identified objects and its characteristics can result in conflicts or data losses in assembly drawings. Data converters from one OD/DB implementation method into another for the same CAD will be needed and so on.
For these and many other reasons, the emergence of successful branded universal common OD/DB CAD solutions would be the best way out because it would give:
- basic CAD features modernization,
- CAD functionality expansion due to the possibilities of software analysis models creation,
- increased CAD utilization efficiency,
- high-quality solution and additional features without any extra costs for users.
Adding branded, complete, convenient and universal OD/DB-solutions outrunning custom developments to CAD can lead to significant reputational winnings for CAD-companies.
Unfortunately, CAD implementation of full-fledged OD/DB is significantly late – it would be well-timed in the begging-middle 2000s.
Universal CAD OD/DB-solution
Universality here is the possibility of OD/DB usage when drawing in any subject area, but not the possibility to solve all the drawing problems.
To date, OD/DB is used by CAD-companies mainly in vertical applications, i.e. as specialized (not universal) solutions. Most custom OD/DB applications are not universal and almost always were created as specialized ones. Obviously, the question rises up: is complete, quality and universal OD/DB CAD solution possible at all?
Positive response is already laid in the assortment and quantity of the existing custom and branded OD/DB-solutions – OD/DB-applications exist or may be developed for every subject area.
The second argument for the possibility of the universal solution is that all specialized OD/DB-solutions make use of the same basic tools and methods. While these tools are independent of drawing subject. Object menu, the possibility to identify graphical elements as objects, characteristics determination – all of these is independent of subject areas.
The third pro argument – CAD have the possibilities to describe object non-graphical additional data, which can be used both to identify graphical elements as objects and to determine objects’ characteristics. These are the capabilities of "extended data" and external databases connection. "Extended data" is used in CAD mostly for internal auxiliary purposes, for internal descriptions of graphical primitives and are used in vertical applications among other things for its OD/DB. This "extended data" can be used for almost any descriptive, non-graphical information for any graphical elements.
All this leads to the conclusion about the possibility of universal common OD/DB-solution in CAD, for CAD.
Obviously, universal common OD/DB-solution will not allow to carry out the task of creating specific models for any subject area, with non-standard CAD primitives. But this is not the subject of OD/DB for CAD. The will always be the need for specialized applications. Modeling with special, non-standard primitives, created for specific subject areas, is the subject of special drawing applications (including ones using OD/DB).
It is advisably to create basic CAD OD/DB for solution of common for all subject areas tasks with the use of standard CAD primitives in order to enable its manipulation with standard CAD tools.
Graphical elements object identification and object characteristics determination tools should not cause unnecessary difficulties for the users. In particular, it makes sense to use internal CAD non-graphical additional data tools instead of external databases. The former is much more advanced – does not require additional third-party software, additional computer capacity, additional user training and additional operations. Finally, it allows to store all the data in CAD files what is usual and very convenient for data storage and transfer.
Despite OD/DB software analysis model creation for basic CAD capabilities, these should not be considered as an alternative to vertical applications’ possibilities in the creation of databases. OD/DB models with identified objects and its determined characteristics are the extended counterparts to conventional CAD drawings.
Therefore, since the main CAD task is drawing, creation of drawings and models, OD/DB database capabilities are advisable to limit with the optimal minimum sufficient to fill the databases, collect data, check their completeness and correctness.
One of the key tasks in the development of OD/DB for basic CAD is the creation of the simplest and the most transparent structure and a way of drawing standards, objects and its characteristics definition. The simplest and most convenient way to define drawing standards could be, first of all, one single definition file and, secondly, text format file. The simplicity of drawing standard definitions creation allows users to describe subject areas rather fast and easily, enables to make urgent edits of the definitions, if any. The appearance of complete and quality drawing standard definitions and its distribution among CAD users with the help of OD/DB enables to improve dramatically the distribution and support of actual (common, governmental, agency, corporate, etc.) standards in the drawings produced.
Continuous and extensive experience in OD/DB use shows that even an incomplete OD/DB implementation (only using object menus for drawing and some additional features of data manipulation and some checks) speeds up drawing creation significantly and improves drawings’ quality dramatically.
In summary: the addition of a complete, quality, universal OD/DB to CAD can play the role in the upgrading of CAD main features – drawing capabilities, drawing creation becomes much more convenient, fast and quality. Furthermore, OD/DB will help to expand basic CAD products assortment – will help to create drawings not only as graphical documents, but also as models suitable for direct software analysis, as the data ready for external, large databases, for analytical information systems. For any basic CAD drawing subject areas.
15.03.16
Alexander Sharov
Translation: Sheviakov Sergei
