Best Like Content

  • Getting Error when launch

    First, make sure you have the latest version of Global Mapper.  If the problem persists in the latest version, please send a description of your workflow, a copy of your data (if possible), and the results to Blue Marble Geographics Support (geohelp@bluemarblegeo.com).  This will ensure that the support team will be notified of the problem and can work on a solution.
    savardajs
  • Cast shadow analysis

    I am currently wondering about the analysis of cast shadows based on the the terrain.

    My background is, that I am trying to simulate the near shading effects by trees, buildings and other elevated objects onto lower terrain to see if the terrain behind / below will be shaded during specific hours of the day.

    I figured out, that the shaded relief function allows for setting of different sun angles and azimuth and so I tried to work with this. However, it appears to me, that this functionality will only display, whether or not a specific area would in theory receive direct sunlight but it does not cast / show the shadow, which an object will throw.

    So for example, I am attaching a view from a 3D model, where I overlaid three hill shading options. The model is located in Yamagata, Japan.

    Option 1 (10:00 am)
    Sun angle 24.5°
    Azimuth 155°

    Option 2 (12:00 pm)
    Sun angle 28.5°
    Azimuth 180°

    Option 3 (14:00 pm)
    Sun angle 20°
    Azimuth 215°

    I am aware, that the above numbers are not 100% correct, but it is accurate enough for my purposes.

    My point is, that the programm just creates dark areas, where there is no direct sunlight, but it does not cast shadows. In this case, there are two buildings in the centers, which are roughly 30m and 40m high and they would probably cast quite far shadows behind them.

    Is there a way to do this? I would like to see, how far shadow is reaching but right now it seems that the programm is not doing that.

    Regards,

    Jakob

    AmitKumar
  • Point Cloud Classification Settings

    When you open the case study and receive the file-not-found screen, edit the address to remove the characters after ".pdf" and the file will then open fine.
    Natscurtisneufeld
  • Point Cloud Classification Settings

    Thanks for response, Katrina.  I have seen the excellent webinar.  The issue seems to be with the higher point densities of the photo generated point cloud.  I will continue to work with smaller sections.  I don't know if there are any recommended settings for such a file as a starting point.  Using '1 point' spacing for the gridding seems to tight, and 1 or 2 meters may be to large.  There are so many settings, it is a little daunting. I know there is personal training available; however, is there a chance to just talk with someone on the phone for a short conversation?  BTW, the link for the case study above did not work.  
    Nats
  • Precision of buffered areas

    Hi there,

    I'm running this technically under a script, but it's also happening in gui mode so under here it goes. Version is 17.2; can provide dongle details if required.

    I'm creating a bunch of buffer areas that have to be precisely on the whole metre. I find, though, that when I create a buffer - be it from the little button or LAYER_BOUNDS_EXPAND, it's always up to 35cm or so out (yes, when checking metadata, not just zooming). My original areas are showing up as precisely on the metre. What's happening?

    We have a bunch of huge projects coming in that require this not to be happening so help would be very very much appreciated, even if just to see what I am missing.

    Alternatively, a way to make elev grids etc line up with the metre is also welcome :)

    Cheers!
    Nats
  • Hydro Flatten with script

    I’ve been playing with the hydro-flattening and have another problem I’m not quite understanding. I’m testing the functionality of different gridding methods and am having some problems when I combine the bin methods with hydro-flattening polygons (note this is just test data). As you can see in the screenshots, the TIN method respects the boundaries of my polygon, whereas the bin method connects parts of the polygon. You see in the screenshot that the bin method has cut part of my data off. The bin parameters are set to only 1m while the gap it is bridging is about 75m.

    Nats
  • GENERATE_CONTOURS function: shader indexing error when generating Iso-height areas

    Tim,

    The issue is that your calculation of the shader levels in meters from the feet value was using a conversion value of 3.2808 hard-coded in the DEFINE_VAR commands. Internally Global Mapper uses 3.2808430145964.

    This discrepancy caused your calculated shader levels in meters to be very slightly higher than they should be, so the area contour heights were just barely below the cut-off in the shader when internally converted from feet to meters using the more exact conversion. Because the shade definition had BLEND_COLORS=NO set, the slight difference caused the lower range to be used rather than the higher range.

    I have fixed this in your script by defining the contour intervals using the following:

    DEFINE_VAR NAME="CVT_FT_TO_MT" VALUE="3.2808430146"
    DEFINE_VAR NAME="CONTOUR1" FORMULA="(%START_CONTOUR_FT% +0) / %CVT_FT_TO_MT%"
    DEFINE_VAR NAME="CONTOUR2" FORMULA="(%START_CONTOUR_FT% +1000) / %CVT_FT_TO_MT%"
    DEFINE_VAR NAME="CONTOUR3" FORMULA="(%START_CONTOUR_FT% +2000) / %CVT_FT_TO_MT%"
    DEFINE_VAR NAME="CONTOUR4" FORMULA="(%START_CONTOUR_FT% +3000) / %CVT_FT_TO_MT%"
    DEFINE_VAR NAME="CONTOUR5" FORMULA="(%START_CONTOUR_FT% +4000) / %CVT_FT_TO_MT%"
    DEFINE_VAR NAME="CONTOUR6" FORMULA="(%START_CONTOUR_FT% +5000) / %CVT_FT_TO_MT%"
    DEFINE_VAR NAME="CONTOUR7" FORMULA="(%START_CONTOUR_FT% +6000) / %CVT_FT_TO_MT%"
    DEFINE_VAR NAME="CONTOUR8" FORMULA="(%START_CONTOUR_FT% +7000) / %CVT_FT_TO_MT%"
    DEFINE_VAR NAME="CONTOUR9" FORMULA="(%START_CONTOUR_FT% +8000) / %CVT_FT_TO_MT%"

    The conversion factor is defined in one place rather than repeated. I used a value that was rounded up at the 10th decimal place rather than use the full exact conversion just in case there is some round-off error somewhere. The very slightly larger value will cause your calculated levels to be very slightly above the GM values rather than below as they are now, causing the proper color to be used.

    Let me know if I can be of further assistance.

    Thanks,

    Mike
    Global Mapper Guru
    geohelp@bluemarblegeo.com
    http://www.bluemarblegeo.com/
    timbot
  • Cut and fill volume calculation

    Hi Adam,

    You can use Analysis > Measure Volume Between Surfaces

    Assuming:
    • DTM2 is the layer to subtract from
    • DTM1 is the layer to subtract

    Measurements:

    Total Volume Between Surfaces: 9947.185 cubic meters

    Cut Volume: 8038.4232 cubic meters
    Cut 2D Surface Area: 4931.6 sq m
    Cut 3D Surface Area: -
    Fill Volume: 1908.7617 cubic meters
    Fill 2D Surface Area: 13809 sq m
    Fill 3D Surface Area: -

    LAYER_COMPARE: DTM2.tif
    LAYER_BASE: DTM1.tif
    REPORT_TIME: 01/06/2017 12:23:07
    AVG_Z_DELTA: 0.327 m
    MAX_Z_DELTA: 5.345 m
    MIN_Z_DELTA: -1.599 m


    Steve
    Nats
  • Exporting LAZ to LandXML doesn't export attributes

    Dear support, I am trying to export a LIDAR file from LAS to Land XML.
    The LAS file has all the attributes in it: returns intensity and so on but they don't come across when I export it to LandXML in Global Mapper version 18.2. Any suggestions?
    Thanks
    Nats
  • How to digitize contour line in an efficient way

    1. Make sure you have assigned the elevations first then (Vertex Editing > Edit Feature Vertices)
    2. Select the lines
    3. Right-click
    4. Advanced Feature Creation Options > Create Point Features Spaced Along Selected Features

    Alternatively, if you have reasonably clean contours you may be able to convert them to lines by creating area features based on the contour colour values and then converting those to center lines:

    1. Right-click the raster layer
    2. Create Area Features from Equal Values in Selected Layer
    3. Choose Only Create Areas for Selected Colors and enter the RGB value of your contour e.g. 0,0,0 for black
    4. Select the newly created area features
    5. Right-click > Move/Reshape Feature(s) > SIMPLIFY
    6. Right-click > Move/Reshape Feature(s) > SMOOTH
    7. Right-click > Advanced Feature Creation Options > Create Area Skeletons/Center Lines
    8. Join any gaps in the new contour lines:
    9. Right-click > Crop/Combine/Split Functions > COMBINE 
    10. Repeat steps 5 & 6 to reduce the points and smooth

    This is an example I created using the above workflow - took around 10-15 minutes. Using the Image Swipe Tool I have shown the original raster on the right and the results of the process above on the left. The image below that shows the raster below the new contour lines.






    fgallice