Watch the video: MapBrowser - 3D Viewer & 3D Export
This article describes:
Measuring lines in 3D
- Once you are in 3D view, click the Line tool.
When you access the Line tool you will see a disk that
- Zoom into the property you want to measure, you might want to rotate your view to get the angle you need for a clear measurement.
- Draw a line along the slope you want to measure by clicking the start and double-clicking the destination point.
The measurements include:
- Line length - the distance between the both ends of the line in meters, kilometres, feet, yards, miles, or nautical miles.
- Pitch - the angle of the line relative to the horizon in degrees or rise/run ratio.
- Relative height - the difference in height between both ends of the line in meters, kilometres, feet, yards, miles, or nautical miles.
Measuring areas in 3D
Use the Polygon tool to measure the area, perimeter and pitch of a surface on Nearmap’s 3D content.
- Once you are in 3D view, click the Polygon tool.
- Draw out a polygon by single-clicking on each desired vertex.
When you access the area tool you will see a disk that snaps to the surface nearest to your cursor. Maintain the angle of this disc to ensure you draw the polygon on the one plane.
- To close the polygon, hover over the start of your polygon until you see a small circle, then double-click.
You can see the area, perimeter and pitch of the polygon.
Tips for measuring 3D area
Check the area you have drawn is on the one plane
The area may look fine from your original viewpoint, but because the area tool snaps to the nearest surface, it may accidentally pick up an object, such as a tree or another structure.
Rotate the imagery to ensure the polygon is tracing the surface you want
Drag and drop a vertex to adjust, if needed.
Drawing multiple faces
For best results draw one plane at a time. Drawing several planes at once may give you unpredictable results.
Note the irregular surface produced
Drawing each face separately
Each face is clean and one its own plane.
Ensure the area you draw makes sense
If you draw self-intersecting sides, you will get an error.
Other ways to edit and manage measurements
Unlike measurements on our vertical content, you can only change the values of line length from Inspector Panel.
However, there is a lot you can do on the map, from Inspector Panel and from Layer Manager to edit and manage your measurements.
Refer to the article Common Measurement Actions.
How do I know if my 3D measurement line end point is at the spot I meant it to be at? —
Lines will begin and end on the surface of the 3D mesh. When using the line tool, a disc is used as a guide to the surface you are hovering over. This disc will reflect the surface slope and angles as you move over them and this can help you decide where to start and end your line.
Read more: Measure 3D Content.
Will there be other measurement tools for 3D imagery? —
The 3D tool set will be expanded over time. We would love to hear what tools you would like included in the future. Contact your Customer Service Manager.
Why is the measurement different to the equivalent one I made on the Oblique map? —
The most difficult part of measuring using either method is accurately picking the top and bottom of the object due to shadows, obstructed views and the limits of resolution. With practice behavior becomes more consistent, and in tests of measuring with both 3D and oblique images, results are consistently within about 1 meter of each other.
Which measurement is more accurate, 3D or Oblique? —
Theoretically, the oblique images offer higher accuracy, but in practice, actual measured accuracy will be determined by how well the endpoints of the measurement can be seen and how well the tool is used to place the start and endpoints. This can be affected by zoom level, perspective, and any obstructions.
What geoid models are used with Nearmap's 3D imagery? —
AU: AHD (AusGeoid09)
Do viewing and measuring 3D content consume my data usage? —
No. Viewing and measuring 3D content do not count towards your standard imagery data allowance. (This is unlike viewing 2D content - refer to About Data Usage for more information.)
Are my 3D lines and measurements saved in projects? —
For information on the Projects tool in MapBrowser, read this article: Projects Tool.
I want to retrieve imagery for an area larger than 100 metres. Can I do this with the DSM API? —
To do this, you will need to make multiple coverage calls (i.e. with a Transaction Token for each), make the image calls and stitch together the images.
Find out more here: DSM and TrueOrtho API
What does "Error: invalid aoi claim: requested AOI is not within allowed AOI in transaction token" mean? —
When using the DSM and TrueOrtho API, your coverage radius is smaller than your image call radius. Ensure your coverage radius is as large as you require.
Find out more here: DSM and TrueOrtho API
Can I request the DSM and TrueOrtho image and have the API return an image using the best possible resolution? —
The physical and pixel size of the image are deliberately explicit to give you control over the image that will be returned. This is further complicated by the fact that True Ortho and DSM are of different native resolutions (0.055 m versus 0.15 m).
Request the imagery by inspecting the coverage response and then calculating the pixel size based on the metadata.
How can I control the resolution of the DSM and TrueOrtho image retrieved? —
The image resolution is determined by the image length (2 x radius) and the size in pixels. This allows us to maintain the location as the centre point of the image. Refer to the examples below as an illustration of how radius and size values determine image resolution.
radius: 10 m
length: 20 m
size: 100x100 px
pixel size: 5 m
What if the radius and size I specify in DSM and TrueOrtho means an image of much higher resolution than is possible? —
In this case, the image returned is the highest resolution Nearmap imagery.
Is the radius I specify in DSM and TrueOrtho a true radius ? —
The radius is not a radial dimension with location as centre point. The radius defines a square bounding box with location as the centre. Note also that the units are real world and not Web Mercator metres.