Welcome to our new forum platform. We realize there is still some work to do and we appreciate your patience. Please let us know if you have any ideas or suggestions: paul@globalmapperforum.com

Slope Direction Arrow Symbology

longitude105longitude105 Global Mapper UserPosts: 6
edited January 2014 in Vector Data
I exported a 3 meter NED elevation model to a .flt format in order to create a layer that retained the slope direction values. I then generated a 3 meter point grid layer and exported that to a shapefile and keeping the slope direction from the .flt layer in order to keep the slope direction as the elevation attribute for each grid point. I would like to display an arrow symbol applied to the shapefile points based on the rotation of the slope direction value. Is there a way to do that? Even if I have to build seperate arrow symbols for each value - there would only be 360 of them that I hopefully could use again. I am basically trying to symbolize a shapefile that would show a flow - somewhat similar to a weather wind chart. Thanks.

Comments

  • global_mapperglobal_mapper Administrator Posts: 17,238BMG Staff
    edited January 2014
    While we plan to add a "quiver plot" option in the very near future, what you can do is set the symbol for the points to one of the Geology symbols (like a small or medium arrow of the desired color) and name the slope direction attribute as "DIP_AZI" (dip azimuth). That should rotate the arrow symbol the desired number of degrees and hopefully get it pointing where you want it.

    Let me know if I can be of further assistance.

    Thanks,

    Mike
    Global Mapper Guru
    geohelp@bluemarblegeo.com
    Blue Marble Geographics for Coordinate Conversion, Image Reprojection and Vector Translation
  • longitude105longitude105 Global Mapper User Posts: 6
    edited January 2014
    Thanks for the reply. I still am having trouble with the rotation. Using ver. 15.1 I am getting the points (as a shapefile) with the rotation that is listed as the Elevation attribute when I generate the center points and export with the slope direction from the .flt formated elevation model. By right clicking on the shapefile in the 'Overlay Control Center' and clicking on the 'Point Styles' tab, I am able to click on the 'Use Same Style for All Features' option and Select the 'geology arrow' symbol to get the points to display as arrows. I am still a little baffled on how to change the slope direction attribute in order to get the rotation. Can you add a little more info on where I am able to do that? I think I am close.
    Thanks again!






    While we plan to add a "quiver plot" option in the very near future, what you can do is set the symbol for the points to one of the Geology symbols (like a small or medium arrow of the desired color) and name the slope direction attribute as "DIP_AZI" (dip azimuth). That should rotate the arrow symbol the desired number of degrees and hopefully get it pointing where you want it.

    Let me know if I can be of further assistance.

    Thanks,

    Mike
    Global Mapper Guru
    geohelp@bluemarblegeo.com
    Blue Marble Geographics for Coordinate Conversion, Image Reprojection and Vector Translation
  • global_mapperglobal_mapper Administrator Posts: 17,238BMG Staff
    edited January 2014
    It does sound like you are close. Once you have the symbol for all of them set to the Geology arrow (any geology type will work, but the arrow is what you want), you need to right-click on the layer in the Control Center and use the CALC ATTR option to create a new attribute called DIP_AZI and copy the value from whatever attribute has the rotation to there. If it's off by 90 degrees call the attribute STRIKE_AZI instead (really depends on what your angles are relative to). Then the rotation should happen automatically.

    Let me know if I can be of further assistance.

    Thanks,

    Mike
    Global Mapper Guru
    geohelp@bluemarblegeo.com
    Blue Marble Geographics for Coordinate Conversion, Image Reprojection and Vector Translation
  • longitude105longitude105 Global Mapper User Posts: 6
    edited January 2014
    Mike,
    Perfect - that works very well. Just what I was looking to do. As always, thanks for the great support and quick response.
Sign In or Register to comment.