Process of creating geometric polygon features.

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5
votes
6answers
11k views

Points to Polygon

I've millions of points collected for lithology layer. They have used a coding for different types of rocks. I need to create a polygon around the extent of similar points. What is the easiest way to ...
4
votes
2answers
659 views

Extract all pixels of given RGB value and render as MultiPolygons

Given a geotiff image with a colortable in it, what is the easiest way to extract each color as its own "layer or shapefile or multipolygon object"? Specifically, I am looking for a programmatic ...
14
votes
3answers
2k views

Producing building shadows?

How would you generate building shadows from building footprints? I have attribute values for the heights of buildings. So would preferably like to have the shadows' sizes vary based on that. The best ...
1
vote
1answer
2k views

How to create a circular sector in Mapinfo?

I want to build a tool that creates a cell sector from data like that below. The sector diagram should be like the second picture. The first picture shows a Mapinfo tab file with the required fields ...
5
votes
3answers
1k views

How to find line length in QGIS while editing?

I am using QGIS (before, I used ArcView). I would like to know if there is any way during the editing phase of a vector (line or polygon) to know the length of the line (total and partial) that is ...
2
votes
1answer
386 views

insert maximal number of circles into polygons [duplicate]

Possible Duplicate: algorithm to place maximum number of points within constrained area at a minimum spacing I'm trying to fit as many 30ft diameter circles into polygons of certain land ...
5
votes
2answers
406 views

ArcMap Draw Camera Range with ArcPy

i am working on some camera data. I have some points which consist of azimuth, angle, distance, and of course coordinate field attributes. In arcmap I want to draw shapes like this: The shape is ...
2
votes
0answers
172 views

How to add address block on Google Mapmaker?

Is it possible to mark a block of addresses for example B-block, xyz colony, which is a logical block of addresses on Google Mapmaker? If possible, how do I do it? I want to add a polygon feature ...
4
votes
2answers
2k views

ArcGIS 10.0/arcpy: How to create a polygon geometry from inner and outer ring point arrays?

I have two arrays, each containing a closed ring of points, one for an outer ring and the other for an inner ring, the latter running counterclockwise, of course. I am using the arcpy.Polygon() ...
6
votes
3answers
2k views

ArcScene: creating 3D polygon features from a DEM

I have a DEM with a lot of topographic variance and a separate layer of polygon features (w/o Z values)throughout. When I use 3D Analyst to convert features(polygon) to 3D, only a portion of the ...
4
votes
1answer
1k views

Create overlapping polygons from contour lines

Working in ArcGIS 10, I have a set of contour lines representing density of commercial square footage, and I have a set of points representing local maxima for each peak of the dataset. For each ...
5
votes
1answer
1k views

How to create a polygon from other polygon boundaries?

I want to write an algorithm that creates a polygon inside a hole made by a set of other polygons. It's something like a flood fill and it's like the "boundary" tool in Autocad. The image shows an ...
8
votes
1answer
2k views

Polygon overlay with Shapely

I'm trying to capture all the non-overlapping polygons indicated below using Shapely (given polygons A,B & C). Moreover, I'm hoping to do so without iteration, testing for intersect etc. The ...
1
vote
1answer
88 views

Online resources for creating shp files performing basic GI functionality

I am looking to build polygons, based on files containing a grid of points. The representation of the polygon would be an aggregation of the points. As the end wares are ESRI, I was wondering if ...
2
votes
1answer
465 views

convert SDE table to polygon feature class with Arcobjects

I figure there's a few ways to convert a table to polygon feature class, but what's the fatest and cleanest way to do it? My table has lat, long, azimuth, and beam width and based on all this info I ...
15
votes
4answers
743 views

Why do valid polygons repeat the same start and end point?

In the GIS world, for most modern formats and Standards (e.g., Shapefiles, WKB/WKT, GML, KML, etc.), valid polygons need to have closed linear rings, which is a linestring of coordinates where the ...
1
vote
0answers
273 views

Spatial Reference and Area/Length Attributes relationship

I currently allow users to add a shape file in. From the shape file, allow the user to generate a new layer base on the polygons from the shape file's polygon they imported. Generating the new ...
1
vote
1answer
626 views

Converting LinestringM to Polygon PostGIS

I'm working with PostGIS and plotting polygons on a Google Earth plugin. I've found a few examples via Google on how to convert a LinestringM to a Polygon for rendering, but none of them, including ...
3
votes
3answers
5k views

How to create a polygon buffer from a line?

I have connected a series of points into a line in ArcMap 10 with the Points to Line tool in the ArcToolbox. The line is, of course, in its own layer, and I added a 5 meter buffer around the line. It ...
3
votes
5answers
585 views

Create a Polygon

I'm working with ArcGis to create a habitat mapping, so I have digitized the most part of my area with different polygons. I would like to create another one but it's really difficult because it is ...
3
votes
4answers
354 views

Creating Polys and Displaying geo points within. ( Where to start? ) [closed]

Hey all, I'm somewhat of a newb when it comes to creating mapping solutions. I've stayed on a pretty high level playing with openlayers and pulling data from various webservices. The first part of ...
4
votes
3answers
2k views

Creating collection of polygons from collection of points?

I have a set of points, which are spread over a wide geographical area. I need to be able to create a set of polygons which best represent the clustered points. In parts, some points may simply lie ...
10
votes
4answers
804 views

Algorithm to calculate coverage + overlaps from a set of arcs

I have a shapefile containing arcs representing the path travelled by a truck spreading fertiliser onto a farm. Let's say I know the spread width is 30m, i.e. the truck can spread fertiliser 15m ...
11
votes
6answers
3k views

How to find the boundary co-ordinates from a given set of co-ordinates

Given a set of coordinates, How do we find the boundary coordinates. <== Figure 1 Given the coordinates in the above set, How can I get the coordinates on the red boundary. Boundary is the polygon ...
2
votes
2answers
2k views

Creating fixed width polygons in ArcMap

I've been adding easements, which typically have a fixed width. Are there any existing tools or scripts that would allow me to define one edge and automatically create the other? The buffer tool is ...
16
votes
1answer
5k views

How to divide a polygon into specific sizes using ArcGIS?

I have several thousand irregularly shaped polygons in a shapefile. I want to be able to split each polygon into three areas, and to specify what the size of those areas (they sum to the previous ...
0
votes
0answers
296 views

How to convert two line to polygon [duplicate]

Possible Duplicate: Lines to Polygons Hi all, this is first my Q, so can any one help me, how to convert two line to one polygon feature, thank you.
12
votes
5answers
8k views

How do I create a convex hull in ArcGIS Desktop?

I would like to be able to create a convex hull in ArcGIS Desktop 9.x, but I cannot find an appropriate tool. How does one go about creating one? I am interested in answers for all license levels: ...