This standard specifies the technical regulations and accuracy requirements for surveying and mapping 1:500, 1:1000, and 1:2000 digital topographic maps using field data collection machine-assisted mapping methods. This standard applies to the surveying and mapping production of 1:500, 1:1000, and 1:2000 digital terrain. Digital topographic maps based on standard surveying and mapping can be used by various departments of the national economic construction for survey, planning, design and construction. GB 14912-1994 Specification for machine-assisted cartography of large-scale topographic maps GB14912-1994 Standard download and decompression password: www.bzxz.net

National Standards of the People's Republic of China
Specifications for computer-aided mappingfo large-scale topographic maps1 Subject content and scope of application
GB14912—94||tt ||This standard specifies the technical regulations and accuracy requirements for surveying and mapping 1:500, 1:1000, and 1:2000 digital topographic maps using field data collection machine-assisted mapping methods.
This standard applies to the surveying and mapping production of 1:500, 1.*1000, and 1:2000 digital topographic maps. The digital topographic maps surveyed and mapped in accordance with this standard can be used by various departments of national economic construction for survey, planning, design and construction. 2 Reference standards
GB79291:5001:1000.1:2000 Topographic map schemas GB148041:5001:10001:2000 Topographic map element classification and codes GB2312 Basic set of Chinese character encoding character set for information exchange SJ2347 General technical conditions for micro digital electronic computers ZBY306.1 Computer Peripheral Equipment Interface Uniform Regulations Part 1 JC-1 Serial Interface 3 General Principles
3.1 Plane and Elevation Control Measurement
3.1.1 Plane Control Measurement. The error of the weakest point of plane control at all levels below the fourth level relative to the starting point should meet the following requirements: 1:500 topographic map surveying does not exceed 5cm
1:1000, 1:2000 topographic map surveying does not exceed More than 10cm. 3.1.2 Elevation control measurement. Regardless of whether leveling or electromagnetic wave ranging triangulation elevation measurement is used, the error of the weakest point in elevation control at all levels below level 4 relative to the starting point should not be greater than 2cm. 3.1.3 For plane and elevation control measurements, on the premise that the accuracy is no less than the above, each professional department can use the standards promulgated by the professional department to carry out operations according to needs.
3.2 Coordinate elevation system and projection
3.2.1 The coordinate system generally adopts the 1980 Xi'an coordinate system, but can also use the 1954 Beijing coordinate system or an independent coordinate system. The elevation system adopts the 1985 national elevation datum. When an independent elevation system is used, it should be measured jointly with the 1985 National Elevation Baseline. 3.2.2 Plane control adopts Gauss-Krüger projection and calculates the plane rectangular coordinates according to the 3° zone. When the projection length deformation is greater than 2.5cm/km, the Gauss-Krüger projection 3° zone or any zone plane rectangular coordinate system can also be used, but the projection surface can use the 1985 national elevation datum, offset elevation surface or survey area average Elevation surface. 3.3 Fractionation and numbering of topographic maps
The map is divided into rectangles (or squares), and its specifications are 40cm×50cm, or 50cm×50cm. The map frames are numbered according to the kilometer coordinate of the gallery point in the southwest corner, with the X coordinate in the front and the Y coordinate in the back. They can also be numbered in the same order as the survey area. For the measurement areas approved by the State Bureau of Technical Supervision on January 14, 1994 and implemented on October 01, 1994
comGB14912-94
, the original divisions and numbers can be used . 3.4 Classification of terrain categories
Flat land: most areas with ground slopes below 2°; hilly land: most areas with ground slopes between 2° and 6°; land: most areas with ground slopes between 2° and 6° In areas between 6° and 25°, alpine areas: most areas with ground slopes above 25°. 3.5 Basic contour distances of topographic maps
The basic contour distances of topographic maps are selected according to the requirements of Table 1 according to the terrain category and the needs of the map. Table 1
base
ratio
this
etc
example
height
foot
ground
Distance
1+500
1:1000
1:2000
Class
Speciality
Note: brackets The contour distance within is selected according to the drawing needs. FlatwwW.bzxz.Net
0.5
Land
0.5(1:0)
1.0(0.5)
Hills
Land
1.0(0.5)
1.0
1. 0
山
1.0
1.0
地
2.0(2.5 )
m
Shangshandi
1.0
2.0
2.0(2.5)
The same scale should be used for each survey area. Contour distance. When the basic contours cannot show the landform features, half-distance contours should be drawn.
In flat areas and urban built-up areas, depending on the needs of the map, contour lines may not be drawn and only elevation points may be used. 3.6 Density of elevation note points
Elevation note points are generally selected on obvious ground objects or terrain feature points, and their density is 5 to 20 per 100cm\ on the map. 3.7 Accuracy of topographic map
3.7.1 The error in the plane position of the feature points
The error in the position of the feature points on the topographic map relative to the adjacent root point and the error in the distance between adjacent feature points The error shall not exceed the requirements in Table 2.
3.7.2 The mid-elevation error of elevation annotation points
The mid-elevation error of an elevation annotation point relative to the adjacent map root point shall not exceed 1/3 of the basic contour distance. Table 2
Land
District
Division
Town, industrial building area
Flat land and hilly land
Difficult and hidden areas|| tt||Class
Scale
1:500
1:1000
1:2000
1:500
1:1000
1*2000
Point error
±0.15(±0.25)
±0.30(±0.50)
±0.60(±1.00)
±0.23(±0.40)
±0.45(±0.80)
±0.90(±1.60)
Note: The error in the points in brackets is the same as the adjacent ground The error in the object point is selected according to the accuracy requirements of the survey map. 3.7.3 The height error of the contour interpolation point
The height error of the contour interpolation point relative to the adjacent graph root point shall not exceed the requirements in Table 3. Neighboring features
Error in point spacing
±0.12(±0.20)
±0.24(±0.40)
±0.48(±0.80)
±0.18(±0.30)
±0.36(±0.60)
±0.72(±1.20)
m
Terrain category
Height error Ha
Note: Ha is the basic contour distance.
3.8 Topographic map symbols and notes
flat
GB14912—94
Table 3
land
1/3||tt ||Topographic map symbols and annotations shall be in accordance with the provisions of GB7929. Hilly land
1/2
Mountain
Land
2/3
Alpine land
1
There are no prescribed features and landform symbols in the formula. Each professional department may make additional provisions based on the needs of the map. However, it should be stated in the technical design document or technical summary.
3.9 Limit error
This specification uses the medium error as the standard for measuring accuracy, and twice the medium error as the limit error. 3.10 Accuracy requirements and inspection of instruments
When the distance measurement involved in this specification is carried out with a distance meter, the nominal accuracy of the distance meter shall not be lower than the accuracy of the first-class distance meter (|mp| ≤ 20mm ); the accuracy of its theodolite is no less than that of the DJ6 type theodolite. The surveying and mapping instruments used must be inspected and calibrated in a timely manner, and maintenance must be strengthened to keep them in good condition. 4 Graph root control measurement
4.1 Accuracy of graph root point
The accuracy of graph root point is measured by the error relative to adjacent control points. The point error shall not be greater than 0.1 × M × 10-3 (m) (in this standard, M is the denominator of the surveying scale); the elevation error shall not be greater than 1/10 of the basic contour distance of the surveying map. 4.2 Map root Burial of point mark stones
An appropriate number of mark stones can be buried at the root point of the map as needed. The burial of landmark stones in urban construction areas or industrial construction areas should be considered to meet the needs of topographic map revision and survey.
4.3. Density of graph root control points
The density of graph root control points (including advanced control points) should be based on the principle of meeting the needs of mapping, and is generally not lower than the requirements in Table 4. Table 4
Map scale
Density of map root control points, number of points/km*
4.4 Map root plane control measurement
1500
64| |tt||11000
16
1-2000
4
The root plane control measurement can use the root triangle (net) or the root wire (net ), mixed network, polar coordinates and intersection points. Encryption at each level of control points should not exceed two times. In areas where it is difficult to lay closed conductors, branch conductors can be laid. When the measurement area is small, the root triangle and the root wire can be used as the first level control. 4.4.1 Root wire measurement
4.4.1.1 The main technical requirements for root wire measurement shall comply with the provisions of Table 5. Table 5
Attached wire length
m
1.3M
Relative closure error
.1/2500
Note: n is Number of measuring stations.
Side
Length
Not greater than 1.5 times the maximum measurement distance of the survey map
Error in angle measurement
General||tt ||±30*
First level control
±20%
Number of measurement rounds
DJ6
1
Azimuth angle closure error| |tt||General
±60\n
First level control
±40\n
GB14912—94
4.4.1.2 Figure root wire The side length is measured using a rangefinder in one direction. Four readings are taken in one test round, and the difference in readings should be less than 20mm. The distance measurement edge should be corrected by weather and addition and multiplication constants. 4.4.1.31: 500.1: 1000 measurement map, when the number of attached conductor sides does not exceed 15, the length can be extended to 1.5 times specified in Table 5. At this time, the azimuth angle closure error should not exceed soil 40\√, and it is absolutely closed. The difference should not exceed 5×M×10-(m). When the wire length is shorter than 1/3 specified in Table 5, the absolute closing difference should not exceed 3×M×10*(m). 4.4.1.4 When the root conductor is laid into branch conductors, its length shall not exceed the length specified in Table 5, and the number of sides shall not exceed 3. Use the DJ6 type theodolite to measure the horizontal angle with one measurement round each for the left and right corners, and the circumferential angle closure error should not exceed 40\. The side length is measured in one direction using a distance meter. 4.4.2 Polar coordinate method measurement
is measured using the polar coordinate method of a rangefinder. Its main technical requirements should comply with the provisions of Table 6. Its side length shall not be greater than that specified in Table 7. Table 6
Number of test rounds
DJ6
1
Side length measurement method
One-way test one test
Ratio| |tt||Example
1500
1:1000
1:2000
4.4.3 Graph root triangulation
Ruler
Half test round is poor
30m
Table 7
test
school
elevation is poor
≤1/7 contour distance
Side
300
Core
Poor ranging reading
20mm
m
Length||tt| |500
700
4.4.3.1 The average side length of the map root lock (network) should not exceed 1.7 times the maximum measurement range of the map. The transmission distance angle should not be less than 30°. Under special circumstances, the individual transmission distance angle should not be less than 20°. The number of triangles should not exceed 12. When the horizontal angle observation direction is more than 3, it should be reset to zero. The tolerances for horizontal angle observation should not exceed the requirements in Table 8. Table 8
Number of measurement rounds
DJ6
1
Note: It is the number of measurement stations.
Error in angle measurement
±20
Half-measurement regression zero difference
24*
azimuth closure error
±40| |tt||4.4.3.2 When the root triangle is used as the first level control, the relative error of the starting side length should not be greater than 1/10000. Triangle closure error
60m
4.4.3.3 The coordinate closure error of a single triangle lock should not be greater than 1×V×M×10-4(m) (n is the number of triangles). 4.4.4 The intersection method is used to measure
graph root analysis and supplementary points, and the edge measurement intersection and angle measurement intersection with verification conditions can be used. The intersection angle should be between 30° and 150°, and the length of the intersection side should not exceed 0.5×M (m). The coordinates calculated by grouping are poor and should not be larger than 2×M×10-*(m). 4.5 Root elevation control measurement
The elevation of the root point, when the basic contour distance of the map is 0.5m, adopt root leveling measurement or electromagnetic wave ranging triangulation elevation measurement; when the basic contour distance is greater than 0.5m When using analytical trigonometric height measurement. 4.5.1 Graph root level measurement
4.5.1.1 Graph root level can be laid out along the graph root point as an attached route, a closed route or a node network. The root leveling measurement should start and end at an elevation control point with an accuracy of not less than four GB14912-94
, and its technical requirements should comply with the provisions of Table 9. Table 9
Instrument
Type
DS10
Adhesion route
Length, ktm
5
i angle| |tt||()
30
Gage line length
m
100
Observations
number of times
and Joint measurement of known points
Adhering or closed route
One round trip each
Note: L is the length of the horizontal route (km), n is the number of measurement stations. To once
flat
round trip measurement is poor, fit or
loop line closure is poor, mm
ground
±40V
4.5 .1.2 When the horizontal route is laid out as a branch line, round-trip observation should be used, and the route length should not exceed 2.5km. 4.5.1.3 When a horizontal route forms a single node, the length of each section of the route shall not exceed 3.7km. 4.5.2 Electromagnetic wave ranging triangular height measurement
Electromagnetic wave ranging triangular height measurement, its technical requirements should comply with the provisions of Table 10. Mountain | | tt | | Ground | | tt | | ±12Vn | The instrument height and gauge elevation are taken to the nearest millimeter. Its route should start and end at each level of elevation control points. Table 10 | |tt | km).
4.5.3 Analytical triangulation elevation measurement
Poor index difference
(\)
25
Poor vertical angle
)
25
Poor closure of attachment or loop line
mm
±40D
Side length measurement method
One-way measurement one Measurement round
Root analytical triangulation elevation measurement, its route should start and end at each level of elevation control points, and the technical requirements should comply with the provisions of Table 11. Table 11
Instrument Type
DJ6
Side
km
Length
A0.5
Side||tt ||Number
13
Number of test rounds
Medium wire method
1
Note, S is the side length (km), n is the number of sides, Ha is the height distance. The height difference of opposite observation is poor, m
0.4S
The connection or loop closure is poor, m
±0.1Han
When the side length is less than 25m, for The direction observation difference should meet the requirement of 0.1m. The height of the instrument and the height of the gauge should be measured accurately to the nearest centimeter. When calculating the triangular elevation, no correction is required when the spherical aberration and refractive difference are less than 1cm. 4.6 Supplements of measuring points
Topographic mapping should make full use of control points and map root points. When the density of graph root points is insufficient, branch lines, polar coordinates and other methods can be used to add measuring points. No matter what method is used, the point accuracy of the measuring station should not be greater than 2×M×10-4 (m) relative to the nearby map root point; the height error should not be greater than 1 of the basic contour distance of the surveying map. /6.5 Field data collection
Field data collection generally uses automated and semi-automated collection systems. For mapping in non-built-up areas, the visual distance manual input method can also be used, and the visual distance length shall be implemented in accordance with relevant regulations. 5.1 Field data acquisition system hardware configuration and software functional requirements 5.1.1 System hardware configuration
5.1.1.1 Automated acquisition system
a.
Electronic speed tester: || tt||h.
Automatic data recorder:
c. Communication interface with microcomputer.
GB14912-94
5.1.1.2 Semi-automatic acquisition system
a: Ordinary optical theodolite (angle measurement accuracy is not lower than DJ6 type theodolite); b. Photoelectric range finder;
c. Electronic handheld device;
d. Communication interface with microcomputer.
In addition to the basic configuration, the above two systems can also be equipped with portable microcomputers, small plotters and printers. 5.1.2 Functional requirements of data acquisition software
5.1.2.1 Record of measuring station header information, including measuring area code, station number, observation date, time, temperature, air pressure, instrument model, instrument number, observer , addition and multiplication constants for bookkeepers and rangefinders, and station instrument heights. The codes for the above items are defined by yourself, but the corresponding information codes should be explained in the design document or technical summary. 5.1.2.2 Observation of partial points of the measuring station
, directional observation of the measuring station and inspection of tolerances: b. Observation records of partial points, including measuring point number, data collection code, gauge elevation, slope distance, The recording format of vertical angle and horizontal angle can be specified by yourself:
c. Deletion of erroneous data.
5.1.2.3 has the function of querying and displaying (or printing) data records and modifying information encoding. 5.2 Field data collection coding
5.2.1 The general form of field data collection coding is: terrain code + information code. 5.2.2 Terrain code is a code representing topographic map elements. The terrain code can use the corresponding code in GB14804, or can also use Chinese Pinyin shorthand code, keyboard menu, and mixed coding. If a non-standard encoding form is used, it will be converted into a code that complies with the topographic map elements specified in GB14804 after computer processing.
5.2.3 Information code represents the connection relationship between a certain terrain element measurement point and the measurement point. With the different methods of data collection, the information encoding methods (such as sequential numbering method, breakpoint numbering method, etc.) are different. No matter what kind of information encoding is adopted, the following principles should be followed: a. Conducive to computer processing of the collected data, b. Minimize intermediate files.
5.3 Technical requirements for field data collection
5.3.1 Sketch drawing
a. When drawing a sketch, in principle, the symbols specified in GB7929 are used for the features and landforms. Complex graphical symbols can be simplified or defined by yourself. However, the terrain code used in data collection must correspond one-to-one with the symbols drawn in the sketch. b. The sketch must be marked with the measuring point number of the measured point, and the marked measuring point number should be strictly consistent with the measuring point number in the data collection record. ;c The relative positions between terrain features on the sketch must be clear and correct; d. The various names, features, etc. that need to be noted on the topographic map must be clearly and correctly marked on the sketch. 5.3.2 During data collection, the setting of the instrument and the orientation check of the measuring station should meet the following requirements: a. The instrument centering deviation shall not be greater than 5mm
b. Calibrate the direction (starting direction) with the farther measuring point (or other control point), and use another measuring point (or other control point) as the check. The plane position error of the check point is calculated to be no more than 0.2×M. ×10-3 (m); c. Check the elevation of another measuring point (or other control point), and its difference shall not be greater than 1/6 of the same height distance; d. At the end of data collection at each station, the calibration direction should be detected . If the test results exceed the limits specified in items b and c, the results of the parts measured before the test must be retested. 5.3.3 When measuring points, read the horizontal angle and vertical angle to the minimum division of the instrument dial; the difference between the zeroing check and the vertical angle index shall not be greater than 1. The maximum distance measurement length is determined according to the plane position accuracy of ground object points specified in Table 2. When the accuracy of the plane position of the object point is selected from the GB14912-94
accuracy specified in the brackets in Table 2, the maximum distance measurement length should not exceed the provisions of Table 13; otherwise, the maximum distance measurement length should not exceed the provisions of Table 12. 5.3.4 The measuring station header should be recorded according to the content proposed in 5.1.2.1. 5.3.5 Measure the instrument height and gauge height to the nearest centimeter; when the addition and multiplication constant correction is greater than 2cm, the correction should be considered. When measuring ground object points, if the prism deviates from the center point of the ground object by more than 5cm, eccentricity correction should be added . 5.3.6 The spacing between terrain points should not exceed the requirements in Table 14. Ridge line points, valley line points, slope line points, mountain top points, basin bottom points, saddle points, etc. are collected according to their terrain changes.
Table 12
ratio
example
foot
maximum measuring length
ratio
example||tt| |foot
maximum ranging length
ratio
example
foot
maximum distance between terrain points
1-500||tt| |200
Table 13
1500
300
Table 14
1+500
15
1+1000
350
1:1000
450
1:1000
30
1:2000
500|| tt||1:2000
700
1:2000
50
m
m
m
5.3 .7 Before daily testing, the data collection software should be tested for trial operation to ensure that it is correct before use. The result data of the input control points need to be printed (or displayed) for verification. 5.3.8 Collation and inspection of data
The collation and inspection of field observation data should be carried out in a timely manner after the completion of a day or stage of collection work. The contents include: a: Check the collected data against the sketch. According to the conditions of the equipment, the inspection can be carried out by using explicit and printed data records to check item by item against the sketch, or a small plotter can be used to draw a sketch for verification; b. When a contradiction is found in the comparison check, such as an error in the sketch, the sketch should be modified according to the actual situation. If there is an error in the data record, the measuring point number, terrain code and information code can be modified. For the horizontal angle, vertical angle, distance, etc. in the record, the Observation data such as elevation are prohibited from modification and must be reworked and remeasured:
c. Delete invalid records and supplement tape measure distance points and public point records that were not recorded in time during the actual measurement; d. Save the inspected and modified data to disk or tape in a timely manner. When using tape to save, it should be recorded twice and checked each time; if it is saved on disk, in addition to checking the recorded data, make a backup. 5.4 Selection of surveying and mapping content
5.4.1 The expression methods and selection principles of various elements of land features and landforms, in addition to being implemented in accordance with GB7929, should also comply with the relevant provisions of this section.
5.4.2 All types of buildings, structures and major ancillary facilities should be surveyed and mapped. Houses are based on the outer corners of the walls, and temporary buildings can be left out. The scale size of visual surveying maps of residential areas or the needs of map use should be appropriately integrated. When the contours of buildings and structures are less than 0.5mm on the drawing, they can be connected with straight lines.
5.4.3 If independent features can be represented by a scale, their outer contours should be measured. If they cannot be represented by a scale, their positioning points or positioning lines should be accurately measured. GB14912-94 | 5.4.5. Water systems and their attachments should be surveyed and mapped according to their actual shapes. The elevation of the canal bottom should be measured and the depth of the canal should be marked. The top and slope foot elevations of embankments and dams should be measured. The outlet and well platform elevation of the spring should be measured, and the depth from the well platform to the water surface should be noted. 5.4.6 Landforms are generally represented by contour lines, and obvious characteristic landforms should be represented by symbols. Elevation points should be measured and noted on mountains, saddles, depressions, ridges, valley bottoms and inclination changes.
5.4.7 Outcrops, independent rocks, terraced ridges, etc. should be measured with a high injection ratio. If the specific height of the slope or steep slope is less than 1/2 of the basic contour distance or the length on the diagram is shorter than 5mm, it can be discarded. When slopes and ridges are dense, appropriate choices can be made. 5.4.8 Cultivated land planted with different crops in several seasons a year shall be based on the main crops in summer. When the land category boundary coincides with linear features, the linear features shall be surveyed and mapped.
5.4.9 The names of residential areas, institutions, schools, mountains, rivers, etc. should be noted according to their existing names. 6 Computer processing of measurement data and machine-assisted drawing 6.1 Basic equipment and requirements required for data processing and machine-aided drawing 6.1.1 Computer
a.
should be selected with fast calculation speed, internal and external memory Computer with large capacity and good compatibility: b.
The computer should be equipped with at least one general external storage device for data exchange; c.
The general technical conditions of the computer should comply with the relevant technical provisions of the SJ2347 standard; d. The computer input and output (I/O) interface should comply with the relevant provisions of the ZBY306.1 standard; The display resolution of the computer should be able to meet the basic requirements of large-scale topographic map graphics display and graphics editing accuracy; e.
f. The computer should be equipped with a disk operating system and a series of software such as the supported assembly language, high-level language, Chinese character system and computer diagnostic program.
6.1.2 Plotter
The resolution of the measuring system shall not exceed 0.002mm/stepa.
b.
The addressable resolution shall not exceed 0.025mm/stepThe zero point positioning error shall not exceed 0.04mm;
c.
d.
The dynamic error shall not exceed 0.1mm;
The single pen repetition error shall be 0.05mm;
e.
f.The effective drawing area shall not be less than 841mm×597mm (A1 format). 6.2 Basic software and functional requirements for data processing and computer-aided mapping6.2.1 The operation of system software shall adopt menus or prompts. All system software shall have good compatibility. 6.2.2 Data communication software:
Solve the online communication between the field measurement data recorder and the microcomputer to realize the one-way or two-way transmission of data. 6.2.3 Control measurement data processing software;
Decode the original field measurement data file, separate the relevant data, and make various corrections to the observation values; establish the network point data structure file and automatically sort the network points; automatically generate coordinate approximate values ??and calculate the adjustment of each control network and line; print out the result table in a certain format, and draw control networks, line diagrams and other functions. 6.2.4 Fragment measurement data processing software:
Classify the original fragment measurement data, calculate the coordinates of the fragment measurement points, process the data of the map edge and the remaining points, etc., to form a fragment point file. According to the point file information, the various measurement points belonging to the same feature are arranged and processed in a certain format to form a graphic file. And there are data editing functions such as query, modification, appending, and deletion of point files and graphic files. 6.2.5 Contour automatic drawing software:
Use discrete elevation points, and take into account the processing of geomorphic lines and fault lines to automatically establish a digital elevation model; automatically track contour lines, disconnect contour lines, and form contour elevation point record files; can edit contour lines interactively; can output contour maps on a plotter.
6.2.6 Graphics editing software:
GB 14912—94
The main functions of this software include adding, modifying, deleting, translating, rotating and annotating various graphics displayed on the screen; it has a windowing function for displayed graphics; it can edit by layer and superimpose layers. 6.2.7 Batch drawing software:
Process the graphic file data, automatically call the corresponding subroutine, draw the corresponding topographic map element symbols and annotations; can perform layered drawing; can draw map lines and grid lines, and can perform map gallery decoration and annotation content specified outside the map sheet; can automatically divide the content that exceeds the area of ??one map, and process the map sheet edge data and graphics. 6.3 Requirements for data processing and graphic editing 6.3.1 Requirements for data processing
6.3.1.1 When editing the original fragmented measurement data, point files and graphic files, only non-measurement data can be modified. 6.3.1.2 In the graphic file, the data should be stored in layers, and the layers can be carried out according to Table 15. 6.3.1.3 The topographic map element codes in the drawing file should generally be implemented in accordance with GB14804, and other topographic map element codes can also be used.
Table 15
Layer
Surveying control point
Name
Residential areas and fences
Industrial and mining buildings (structures) and other facilities
Transportation and ancillary facilities
Pipeline and ancillary facilities
Water system and ancillary facilities
Boundary
Landform and soil quality
Vegetation
Note
The encoding of the Chinese character information shall be implemented in accordance with GB2312 standard. 6.3.2 Steps and requirements for graphic editing
Layer
1
2
3
4
5
6
7
8
9
10
No.
6.3.2.1 Before editing graphics, draw a monochrome (or multi-color) editing sample map in layers according to a certain scale. 6.3.2.2 Based on the drawn editing sample map, according to the sketch drawn in the field and the actual situation, in accordance with GB7929 and the topographic map editing principles in Section 6.4 of this standard, or according to the user's requirements, determine the content that needs to be modified and added, and then perform layered editing of the map outline, grid and elements.
After the layered editing is completed, a check map of the corresponding scale should be drawn to find out the existing problems, and the relevant layers should continue to be modified until a complete and satisfactory topographic map is edited. 6.4 Editing principles of topographic maps
6.4.1 Residential areas
a. A 0.2mm gap should be left at the junction of a block and a road; b. Buildings built on steep slopes and slopes should be drawn according to their actual positions. When the steep slope cannot be drawn accurately, they can be shifted and shown with a 0.2mm gap;
c.
When a house built on water coincides with the water edge, the house should be shown as usual without interrupting the water edge.7 Batch drawing software:
processes the graphics file data, automatically calls the corresponding subroutine, and draws the corresponding topographic map element symbols and annotations; it can perform hierarchical drawing; it can draw lines and grids Network cable, and can carry out gallery decoration and annotation content specified outside the picture frame; it can automatically segment content that exceeds the area of ????one picture, and handle edge data and graphics of the picture frame. 6.3 Requirements for data processing and graphics editing 6.3.1 Requirements for data processing
6.3.1.1 When editing original part measurement data, point files and graphics files, only non-measurement data can be modified. 6.3.1.2 In the graphics file, the data should be stored in layers. The layering can be carried out by referring to Table 15. 6.3.1.3 The topographic map element codes in the drawing file should generally be implemented in accordance with GB14804, and other topographic map element codes can also be used.
Table 15
layer
measurement control points
name
residential areas and gates
industrial and mining buildings (structures) and Other facilities
Transportation and ancillary facilities
Pipelines and ancillary facilities
Water system and ancillary facilities
Environment
Boundary
Landform and quality | |tt | 6.3.2 Graphic editing steps and requirements
layer
1
2
3
4
5
6
7
8
9
10
No.
6.3.2.1 Before graphic editing, according to a certain scale, Draw single-color (or multi-color) editing samples in layers. 6.3.2.2 Based on the drawn editing sample map, based on the sketch drawn by the field and the field conditions, in accordance with the topographic map editing principles in GB7929 and Section 6.4 of this standard, or in accordance with the user's requirements, determine the content that needs to be modified and added. Then perform hierarchical editing of outlines, grids and elements.
After layered editing, an inspection map of the corresponding scale should be drawn to identify existing problems and continue to modify the relevant layers until a complete topographic map that meets the requirements is edited. 6.4 Principles for editing topographic maps
6.4.1 Residential areas
a. At the connection between blocks and roads, o.2mm spacing should be left: b. Buildings built on steep slopes and slopes are drawn according to their actual positions. When the steep slope cannot be drawn accurately, they can be represented by shifting and leaving a 0.2mm space;
c.
When a house built on the water coincides with the water line, the house will be displayed as usual, and the water line will be cut off.7 Batch drawing software:
Process the graphic file data, automatically call the corresponding subroutine, draw the corresponding topographic map element symbols and annotations; can perform layered drawing; can draw map lines and grid lines, and can perform map gallery decoration and annotation content specified outside the map sheet; can automatically divide the content that exceeds the area of ??one map, and process the map sheet edge data and graphics. 6.3 Requirements for data processing and graphic editing 6.3.1 Requirements for data processing
6.3.1.1 When editing the original fragmented measurement data, point files and graphic files, only non-measurement data can be modified. 6.3.1.2 In the graphic file, the data should be stored in layers, and the layers can be carried out according to Table 15. 6.3.1.3 The topographic map element codes in the drawing file should generally be implemented in accordance with GB14804, and other topographic map element codes can also be used.
Table 15
Layer
Surveying control point
Name
Residential areas and fences
Industrial and mining buildings (structures) and other facilities
Transportation and ancillary facilities
Pipeline and ancillary facilities
Water system and ancillary facilities
Boundary
Landform and soil quality
Vegetation
Note
The encoding of the Chinese character information shall be implemented in accordance with GB2312 standard. 6.3.2 Steps and requirements for graphic editing
Layer
1
2
3
4
5
6
7
8
9
10
No.
6.3.2.1 Before editing graphics, draw a monochrome (or multi-color) editing sample map in layers according to a certain scale. 6.3.2.2 Based on the drawn editing sample map, according to the sketch drawn in the field and the actual situation, in accordance with GB7929 and the topographic map editing principles in Section 6.4 of this standard, or according to the user's requirements, determine the content that needs to be modified and added, and then perform layered editing of the map outline, grid and elements.
After the layered editing is completed, a check map of the corresponding scale should be drawn to find out the existing problems, and the relevant layers should continue to be modified until a complete and satisfactory topographic map is edited. 6.4 Editing principles of topographic maps
6.4.1 Residential areas
a. A 0.2mm gap should be left at the junction of a block and a road; b. Buildings built on steep slopes and slopes should be drawn according to their actual positions. When the steep slope cannot be drawn accurately, they can be shifted and shown with a 0.2mm gap;
c.
When a house built on water coincides with the water edge, the house should be shown as usual without interrupting the water edge.
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