The study and practice of making maps.

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12
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3answers
4k views

Cartographic techniques for symbolizing routing data

Some common problems with displaying routes created from street data, such as bus routes, include: Routes may overlap themselves, such as when a route takes the same road in opposite directions ...
19
votes
10answers
3k views

Discontinuous or Interrupted map projections?

Do any of the current open source GIS softwares support discontinous projection systems? E.g. sinusoidal, dymaxion, butterfly, etc? If not, are there any affordable commercial ones that do (affordable ...
27
votes
4answers
3k views

How to use directional shading on boundaries for cartographic effect?

The attached screenshot of a National Geographic map shows some beautiful directional shading of boundaries. I'm trying to reproduce this sort of shading for a burn perimeter map, as I want to ...
8
votes
2answers
676 views

Creating summary table of symbology of all datasets in multiple MXDs?

This is related to the following Retain ESRI symbology in Mapinfo TAB . As an initial step (in arcpy) I want to access the symbology of all the datasets and create a document which has the details of ...
24
votes
9answers
3k views

Effectively displaying demographic data on a printed map

I would like to plot the following per zone (30 zones total) data on a printable/non interactive map: Average age Average household income Number of households Population density Number of people ...
17
votes
7answers
4k views

Creating trade flow maps in ArcGIS for Desktop (or any free software)?

I am trying to represent trade flows on a world map where the size and direction of arrows indicate the exports/imports of a given country. This type of map is commonly found in magazines and ...
6
votes
4answers
10k views

How to reproject base layers in OpenLayers?

The issue is: I have vector/topo/image tiled maps for some places in north america which were published as ArcGIS Server REST service. These maps (A) are based in EPSG26912 projection. Now I wanna ...
22
votes
9answers
2k views

Good Symbology for Interactive Web Mapping

When a user clicks on a map what should they expect to see? I would say a symbol for where they clicked. A pushpin seems to be the most accepted icon for generic data. Google has pushed the upside ...
11
votes
7answers
1k views

How to implement value-by-alpha map in GIS?

I've been doing some background reading about cartograms recently and stumbled upon interesting alternative - value-by-alpha maps. Concept is described in more details here and full paper is ...
17
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3answers
779 views

How much Water on Earth(USGS) : A Wrong Map representation?

I happened to read a USGS article, How much water is there on, in, and above the Earth? showing a representation of all the water(which includes water from Oceans, Seas,Bays,Ice caps, Glaciers, ...
5
votes
6answers
8k views

How to represent several points with same coordinates on map? [duplicate]

I'm working on Arcgis 10. I have a point shapefile representing events with several points having coinciding coordinates (They have the same coordinates). For representing them in a dynamic way, I ...
22
votes
3answers
5k views

How to hide “internal” polygon boundaries?

We've been scratching our heads over how to tackle this for some time, and are no more illuminated than when we started. I hope you can help. Our task is thus: how to draw a lake with a solid outer ...
47
votes
8answers
2k views

One dimensional map of the world?

Bit of a strange question but hope this is OK to ask here. Has anyone heard of a '1-dimensional' projection of the world map - that is mapping all the points on the globe to a single line? I was ...
8
votes
3answers
559 views

How do I compare two maps to determine which is better?

I'm trying to do an objective comparison of two different maps for the same region. At the moment, I'm struggling with defining criteria that will allow me to do a dispassionate evaluation. Does ...
6
votes
2answers
166 views

Removing features whose labels are not displayed?

Using ArcMap 10.0, I am working on a map that shows many villages. Each village has a name attribute that I want to use for a label, but in some areas there are so many villages that not all can be ...
6
votes
1answer
446 views

locating latitude-longitude point in a piste-map with matrix transforms

I am trying to plot points of a particular latitude longitude on this image of a Swiss mountainous landscape. What I am doing is I have some 54 known location-points plotted on this image (not ...
82
votes
13answers
4k views

How to account for Colour Blindness when designing maps?

Depending on what you read, 7 to 15% of the general population has some form of colour blindness. That's a significant amount of people. Do you try to account for this in your map designs? If so, how? ...
25
votes
2answers
10k views

How to style beautiful road maps with QGIS?

I am trying to design a beautiful map using Qgis. As I'm a software developer not a designer, I was hoping that this will be easy, but it isn't! There is a similar question here Qgis tutorials and ...
14
votes
4answers
2k views

Is there a name for deformation-based maps?

I have already seen maps using deformation to visualize information. For example, this map shows temporal distance between some French cities when traveling by train: Is there a name for this kind ...
24
votes
2answers
2k views

Why do we use the terms “longitude” and “latitude” for a spherical body?

To specify a geographic coordinate we use the terms “longitude” and “latitude”. Far as I know, these terms derive from the Latin latitudo (= breadth) and longitudo (= length). In German we use the ...
7
votes
2answers
283 views

How to display nebulous boundaries between regions with indistinct edges?

I'm trying to map the boundaries between regions which don't necessarily have a hard edge. For example, areas where languages predominate don't have a distinct edge, but instead have a degree of ...
6
votes
5answers
3k views

Manually classifying graduated data outside of range in ArcGIS for Desktop?

I have two shapefiles representing grids with values that are symbolized with graduated colors, shown below: You can see that the two shapefiles encompass similar ranges of data, but assign ...
5
votes
2answers
244 views

Which true type editor do you use to create/modify point symbols for GIS?

Which true type editor do you use to create/modify point symbols for GIS and what are the advantages and disadvantages of the tool? I am looking for a true type editor to create/modify custom point ...
7
votes
3answers
6k views

QGIS- How to create an “area of interest” polygon mask

I've created a GP tool using ArcGIS that creates an "area of interest" mask from selected features. Effectively it creates a new donut polygon layer where the hole was the previously selected ...
11
votes
7answers
2k views

Color palette conventions

I wonder if there is a "unified" source for map color conventions, that GIS map builders are encouraged to follow? EDIT To clear up my question a bit. I'm more interested in the color <-with ...
3
votes
1answer
347 views

Is it possible to draw a 3D Choropleth Map in ArcGIS?

What I have in mind is something like these two examples below: Also, if it is not possible to create a 3D choropleth map in ArcGIS, is there some other GIS software package that can draw 3D ...
5
votes
1answer
513 views

what dictates the drawing order of overlapping features with in the same layer/feature class in ArcGIS?

I know that in ArcGIS drawing order is controlled by layers, and if I want to make some features be drawn on top of other features I can use definition queries to separate them into different layers ...
4
votes
1answer
1k views

Getting a constant background color for transparency

I am creating a series of tif files at 1:10k scale over a vast area (760 tiles) using arcpy.mapping.ExportToTIFF and then stitch them together to create a single ecw. The output looks ok but when I ...
16
votes
5answers
2k views

Rendering overlapping lines

I am making a map containing information about public transportation: busses, trams, etc. The map will have a layer containing for example the tram lines. Each line has its own colour, and is ...
41
votes
4answers
7k views

Why has Web Mercator (auxiliary sphere) become the web map standard?

I understand what the difference is between the Web Mercator projection and Web Mercator Auxiliary Sphere (WMAS). I also understand that both Google and Esri have adopted this projection as their ...
17
votes
5answers
11k views

How to produce a better inset map?

Attached is an example of a generic inset map designed in ArcMap 10. For all the wonderful things that this software can accomplish, there has to be a more sophisticated way to produce better looking ...
24
votes
5answers
2k views

Coloring thousands of polygons so each is distinct from its neighbors?

I am using ArcGIS 10, and I have layers of the 2010 Census blocks, block groups, and tracts. There are thousands of polygons in these layers. I want to color them so that each is distinct from its ...
11
votes
1answer
2k views

How to create desire lines in QGIS?

How can I show the flow coming from an Origin-Destination matrix as desire lines? I need a result like the one in the picture below. I need to scale them proportionally to its value (coming from a ...
14
votes
3answers
709 views

Using GIS tools for non-geographical problems

Many other fields have visual/"spatial" problems that can potentially be solved with GIS tools. I know I've used GIS tools for the odd non-geographical task and was wondering how much this happens and ...
12
votes
3answers
1k views

Crime mapping symbology

Are there any standard, publicly available symbol sets for crime mapping? What are their intended applications and their strengths and weaknesses?
7
votes
2answers
2k views

Can shaded relief be “blended” with DEM colour ramp in ArcGIS to produce a more visually dramatic result?

Not being able to use true transparencies with ArcGIS colour ramps where only solid colours are allowed has me always wondering about how to improve the look of the surface in my maps without ...
5
votes
3answers
4k views

How to style points in QGIS based on multiple attributes

While trying to find a useful way having earthquakes displayed, I noticed that it isn't that easy to manage. I'd like to be able to recognize the "Magnitude", "Date", and "Depth" from the style of ...
6
votes
5answers
746 views

Provincial Base Mapping Data Sources in Canada

I'm very familiar with the Ontario Base Mapping Data, and am looking for similar data for other Canadian Provinces. Perhaps we can start a list of resources here? I'm looking for something at a larger ...
9
votes
3answers
401 views

Setting symbol descriptions of ArcMap layout legends from table?

ArcMap has the ability to show an extended description for each item in the symbol list. How can I populate that property from a table? The goal is to avoid having to edit each symbol one by one in ...
17
votes
1answer
3k views

How to represent overlapping lines in ArcGIS for Desktop? [duplicate]

I have lots of lines (in one feature class) which share the same location but I want to represent them as lines that are next to each other because they have different properties (different OWNERS). ...
7
votes
2answers
828 views

How can I make segmented roads appear as one line?

I am footling around with Quantum GIS and the British OS Strategi dataset. If I render the roads with a simple line style they look fine: However, if I apply something slightly fancier, it looks ...
2
votes
1answer
305 views

Gdal_polygonize: How to filter pixels above a given value (elevation)?

Given a topographic GIS raster of one country: Given an elevation threshold n = 50 (meters) How to polygonize pixels when z >= n ? gdal_polygonize.py is not clear on this point. It states This ...
14
votes
2answers
1k views

Polygon gradient fills / tint bands in QGIS

Is it possible to use a gradient fill on a polygon in QGIS? I would like to have my polygons with a colour at the edges, fading to clear/white as it moves away from the edge. The majority of the ...
6
votes
3answers
2k views

How to normalize choropleth maps of census information?

I'm trying to improve on the census-based maps on this site, which shows census values at 5 scales from Collection Districts through to State. Currently the maps show whole numbers (eg total ...
3
votes
1answer
206 views

Declination Diagram

What point on a UTM map does the declination diagram refer to? Is it the centre? Is it the edges? Is there a standard? The central meridian on a UTM map points to true north. Are grid north and true ...
0
votes
1answer
728 views

How do i create a flow line map for my data? [duplicate]

I am trying to illustrate a passenger travel flow map from a road terminal to several destinations on a road layer. I have QGis and ArcGIS, but I don't know much on how to start the work. I already ...
6
votes
2answers
2k views

Retain ESRI symbology in Mapinfo TAB

Is there anyway to retain/easily transfer symbology from ESRI to Mapinfo? The only process I found was posted in 2010 - https://groups.google.com/group/mapinfo-l/browse_thread/thread/883223ff4ae56809 ...
5
votes
2answers
769 views

What does Scale mean in the reference of Desktop GIS or WebGIS?

I'm having trouble understanding the meaning of the concept of scale when it comes to maps on screen, i.e. either in a Desktop GIS or in a WebMap. When it comes to paper maps, the idea is very clear. ...
3
votes
2answers
261 views

Display two-dimensional color gradient for two different quantities

I have two overlapping raster layers. One contains quantity A from 0 to 100, and the other contains quantity B from 0 to 100. I'd like to create a map displaying both sets of data at once based on a ...
2
votes
0answers
40 views

Generating a map from a shapefile using ms4w mapserver [duplicate]

I am trying to generate a map from a shapefie. Through some initial searching, I wrote the code below but I am getting just a white page. Below is my code: MAP # To enter comments into a mapfile ...