Global Mapper v25.0

polygon maps

energy
energy Global Mapper UserTrusted User
edited April 2012 in Suggestion Box
Hi mike
we calculate coal reserve frequently via polygon methods in the projects , before the end of the projects,we created polygon maps periodiacally
first draw a polygon map in corel draw and then open the map in GM and then measure everyone polygon area, also we create thematic map according to area,caloric values,thickness....in GM
the process takes some time and also there are diferrence slightly areas
so is that possible to draw polygone map automatically and measure each borehole's area?

1.jpg

Thanks....
1.jpg 50.1K

Comments

  • global_mapper
    global_mapper Administrator
    edited March 2012
    What is the process to create the polygon area for each borehole? Is it just a rectangular buffer some distance in size around the borehole? If so you could create those by selecting the points with the Digitizer Tool, then doing a range ring calculation with the box checked to create rectangles rather than rings, to get the boxes around the selected points. The measured area of each feature should automatically be added as attributes, or if you have existing polygons you can select those with the Digitizer Tool, then right-click and select the option to add feature measure attributes.

    Thanks,

    Mike
    Global Mapper Guru
    gmsupport@bluemarblegeo.com
    http://www.globalmapper.com
  • energy
    energy Global Mapper User Trusted User
    edited March 2012
    unfortunately mike
    the process is like picture; blue lines and red lines are perpendicular,according to each other.Blue line is between 2 boreholes (they are neighbors) red line is perpendicular to blue line............... so total of the red lines that passed the middle of the boreholes are create polygone map.

    polygon.jpg

    thanks..
  • global_mapper
    global_mapper Administrator
    edited March 2012
    Ah I see. There isn't currently any way to do that, but it does look like a cool feature. I've added this to the todo list.

    Thanks,

    Mike
    Global Mapper Guru
    gmsupport@bluemarblegeo.com
    http://www.globalmapper.com
  • energy
    energy Global Mapper User Trusted User
    edited March 2012
    Thanks mike it will be great ,we use frequently also always , polygon method is used on coal and stratified beds mining,if it is,
    GM will be appreciated to us....
  • ChuckB
    ChuckB Global Mapper User Trusted User
    edited April 2012
    Hello,

    What it looks to me like you are looking for is the "Voronoi Diagram" (or "Polygon Map") that corresponds to the "Delaunay Triangulation" for your point set. Or at least that's the terminology computational geometry books use. A Delaunay Triangulation seems to be what is called a "Triangular Irregular Network" or "TIN" in the context of geography.

    Back around 1995 I wrote routines to do this in the context of electronics, not geography; two electrical dimensions instead of two spatial dimensions. It let me generate contours of a measured electrical parameter, kind of like elevation versus two spatial dimensions.

    I found it a bit tricky to program but got there eventually. It is not computationally unreasonable to do since one can recursively divide the point set in half down to something fairly small which solves fast and then go back up the tree, stitching the solutions together.

    I think one can find code to do this online these days.

    Chuck
  • energy
    energy Global Mapper User Trusted User
    edited April 2012
    I didnt know "voronoi diagram" but I have searched a bit , yes that looks like polygon map, we calculate reserve of sedimentary(tabular) bedded usually via polygon map method which based on:share the distance(space) equally between two points(boreholes),there is the line passing the between two points and ther are other(main) line perpendicular to first line and passed the midle of the first line.

    some great mining software like gemcom products(minex,surpac) are using this method for tabular, bedded minings, for exemple coal mining ,after creating polygon map,we draw edge of the coal spread line(from the last boreholes, the edge polygon areas withstand the edge line) a bit diferrent thing, there arent polygon area for non-coal boreholes.