Based on the author's working experience in MICROSTATION software application for many years, taking the design and production technology of MICROSTATION map symbol library as the research object, this paper first briefly introduces MICROSTATION, and then discusses the basic methods and ideas of creating map symbol library based on MICROSTATION. The full text is the theoretical sublimation of the author based on his long-term work practice, which is believed to have important reference value and significance for colleagues engaged in related work.

Keywords: MICROSTATION map symbol library design

China Library Classification Number: TP3 Document Identification Number: A Document Number:1672-3791(2012) 05 (a)-0048-02.

Introduction to 1 Microstation

Microstation is a CAD software and powerful graphic design system introduced by Bentley Company. The secondary development on it mainly benefits from its drawing tools and development language (UCM). Through the extensive application of the software, the author thinks that the software system has the following functions and characteristics.

(1) The user environment is graphical, so people can operate the software flexibly and conveniently, and it is also convenient for people to master the usage of the software. (2) Relevant dimensions, patterns and section lines can change with the change of graphic boundaries and be updated automatically. (3) There are a variety of line types, including smart lines, user-defined lines and multi-line drawing tools, which can not only simplify the operation, but also realize what you see is what you get. (4) Unique reference file function, which can be used by people in a design team to communicate and coordinate, that is, the latest design drawings can be used for interoperability. (5) Software can also be customized, that is, software users can adjust the interface according to their own specialties and habits. As easy to use as the software we developed ourselves. (6) The software has eight views, and the switching, adjustment and switching of these views are very arbitrary, which is extremely arbitrary for people who need to operate across views in many cases.

Analysis on the basic idea of creating symbol library

In cartography, map symbols are divided into three categories: point symbols, line symbols and area symbols. No matter what kind of symbol is displayed in the figure 1, it can be distinguished by the difference of shape, size, direction, brightness, density and color. These symbols are used to express the quality, quantity and distribution properties of different things, thus expanding the expressive power of maps.

2. 1 Preparation before establishing symbol library

2.1.1MicroStation unit setting

The maximum accuracy of the map is determined by the work unit, which is the first thing to set when entering MicroStation software. In map making, the main unit and sub-unit are generally set to: mm. 1, and the sub-unit is 1000 minimum resolution, so the accuracy in the design file is 0.001mm. The operation steps are as follows: when making symbols, first open the reference grid, set the main point spacing to 1 mm and the secondary point spacing to 0. 1mm, then lock the grid, and lock the cursor step size to 0.66.

2. 1.2 Determination of symbol unit name and line name

In MicroStation, the unit name and line name cannot exceed 6 characters, and the quality of symbol names is related to the convenience of use, such as: (1)R00 1, the capital of residential class. (2)T2 10 traffic layer railway.

Here, the element layer code adopts the method of combining letters with element identification codes.

2.2 point symbol creation based on MicroStation

Point symbols have fixed graphics and exact orientation, so there are some independent point objects on the map, which are generally represented by point symbols.

To create a symbol in the symbol library, you must have some elements of the symbol, such as the range of the symbol, the coordinate origin of the symbol, the type of the symbol and so on. When using symbols in the symbol library in MicroStation (if you want to draw a symbol at a certain point (x, y)), the use process is as follows.

First, find the symbol library linked to the vector diagram, and then locate the symbol to be drawn. Take x and y as the origin of the position of the symbol, and you can draw the symbol at this point. The definition of origin is set by the cell origin in the cell tool. The range is defined by the fence box.

When you create a symbol in the symbol library, you can draw the symbol yourself, which is similar in nature to drawing. You can also use various drawing tools in the software, mark them with text, or use existing symbols in the symbol library. In other words, the symbols in the symbol library can be made very beautiful and three-dimensional by fully applying the drawing tools.

The steps to create a point symbol can be summarized as follows.

(1) First, in MicroStation, the subfile is referenced as the file name stored after the dot symbol is created. Then set the properties of the symbol, including color, line type used, work unit, scale and the layer where each element of the unit is located. (2) selection of cell bank. You can connect to an existing cell library in MicroStation. Click Element in the menu and select Cell to open the Cell Library dialog box. Click File and Connect to connect an existing cell library or create a new cell library. Click File in the dialog box, and then click New to create a new cell library. (3) Use drawing tools to draw the shape of the symbol according to its actual size. (4) Determine the constituent elements of the symbol, which can be selected by using the selection function or the fence function. (5) Defining the cell origin can be realized through the cell origin in the cell tool. (6) Open "CellLibrary" and a dialog box will pop up. Click the "Create …" button to open the "New Cell" dialog box, where you can specify the cell name and comments, select the cell type, and finally click the "Create" button to complete the creation of the cell.

2.3 Establishment of Linear Symbol Library Based on MicroStation

You can use MicroStation predefined linear library to realize the symbolization of linear elements. Linear symbols can be decomposed into several straight lines, dotted lines and point symbols, and symbols can be drawn by entity positioning coordinates. It refers to the symbol of elements that express the length according to the scale on the map and define the width according to the requirements on the map. You can customize the linetype to design and draw line symbols. The definition of line type is completed through the line type editor. MicroStation has powerful user-defined linetype function, and can design any linetype we need. For example, dash-dot lines and interval lengths can be controlled by users, and symbol placement, line offset, line width and color setting can be automated. In the symbolic description of linear features, the name, layer and color of lines can be recorded, and attributes such as drawing commands can be set freely. These programs can be called when drawing.

The general process of making linear symbols is as follows.

(1) Determines which basic components represent the composition of linear symbols. (2) Open or create a new line library in the online editor. (3) Establishment and customization of basic components. Composite components should be customized to form line components and point components. (4) Create the name of the linear symbol, which can be created in the linear library and linked with the linear member representing the symbol. (5) The saved line type is shown in Figure 2.