Global Mapper v25.0

I like to create lines in globalmapper that follows a specific slope. Is it possible?

We like to create lines that follow a specific slope. The application is for all water flows, trenches and gravitational pipelines and so forth.

Answers

  • bmg_bob
    bmg_bob Global Mapper Programmer
    Hello,

    You can create a watershed using the Analysis | Generate Watershed... menu item.  Is that what you are looking for?

    Cheers,

    Bob
  • tjhb
    tjhb Global Mapper User Trusted User
    edited June 2016
    I think the idea is literally like contours, only applied to slope rather than elevation.

    The purpose is to draw lines which, if followed, would give a path of constant 3° downhill slope, for example, to run a trench or pipeline with this degree of constant fall.

    I have thought about this too, but have not yet found what works. I don't think it is as simple as contouring slope, i.e. the first derivative of Z. Bringing the second derivative in too might be promising? Or remapping slope so that target slope maps to 1, with values higher or lower tending to zero (1 - Abs(target - actual)), then using watersheds on the derived raster to create ridge lines?

    How did the Romans do it??
  • thjb, you are correct, we use it in agriculture a lot to create what we call contour walls to take water out of fields.  Think it should be a function in global mapper because it is used in a lot of industries.
  • bmg_bob
    bmg_bob Global Mapper Programmer
    Answer ✓
    Hello,

    I have added feature request #19496 to our task list so we can evaluate this functionality for inclusion in a future version of Global Mapper.  We will post a message on this thread when the status of the request changes.

    Cheers,
    Bob