CAD, GIS, or both?

... to sell the capacities of What does Free software is more difficult than convincing an official to commit a criminal offense (piracy) By What does not Expensive software.

Cad dog Recently Bentley has launched a campaign to promote Bentley Map, using as an argument, that it is not necessary to be thinking separately if both can be handled by a single tool. On this, several comment that we are very close to reducing the gap and stop using the words CAD / GIS separately.

There are different points of view, some by economic aspects, others by specialty, others by stubbornness, but in practice with so much technological advance, we continue to struggle with the same problem.

1 The practical case It happens that to implement a cadastre (To use an example), the vector construction, of lines that stretch, cut, rotate, drag, load images, etc. continue to be done in AutoCAD or Microstation. If we ask the technicians why they prefer it they will say:

ArcGIS is not practical for that

GvSIG has tools but runs very slow (on Windows)

Manifold is very unknown and does not have enough tools

Line editing is easier than polygon editing

Support for IntelliCAD is not the same

Then we must do all the construction of spaghetti, in the levels, colors, respective thicknesses, to then pass it to ArcGIS and there build the polygons. When we do this we find Topological errors (That does not recognize CAD), we make modifications and we return to make the changes in the vector, with a cycle that in massive processes ends someday. But in the daily routine of permanent updating, to be changing the CAD and the GIS is a can that finally becomes inconsistent data.


Then, if we want to do something further, we put it into a spatial database (I insist, by way of example), the CAD coordinates, which we see in three decimals but have an accuracy of more than 10 decimals, only have three, which means that the vector is no longer exactly the same, as long as it does not affect the speed of processes in the database. Here the update without topological criteria is much more complex.

And as for the economic, a small municipality should invest in A software To construct precise vectors and Another for make beautiful maps. If the municipality is stingy or (believes that) does not require an engineering program to use at least one AutoCAD Lite and one ArcGIS plus two extensions; however cheap it is, they are more than $ 4,000 (Without training). Those who have worked with municipalities will know how much it costs to sell this amount to a treasurer who commands more than the mayor.

I know, there are municipalities that do not have these barriers, but the generality of the Hispanic context ... lives that reality for reasons of wanting to do GIS and CAD without smoking astral.

2 The GIS should have CAD capabilities

I understand that when there was ArcView 3x it was not possible to implement vector building tools with topology management, but at this point, I do not understand why we do not have tools in the GIS that only do what the CAD does (30 stuff)

  • 12 buttons to create (lines, arcs, circles, polylines, points ...)
  • 12 buttons to edit (parallel, copy, move, rotate, extend ...)
  • A handy snap control (sorry for my insistence as well as in the CAD)

Surely these things already have them, but we complain about the procedure. They should be similar to how popularized programs are made, with easy handling of directions, distances, coordinates, extension, drag, clipping ... nothing astral, just as AutoCAD or Microstation do. In this regard, the best thing we have seen has been the effort of gvSIG, which instead of reinventing the way of making vectors, was adapted to the form of Do it with AutoCAD, With millions of users in the world doing so (Aware that AutoCAD has archaic procedures). Work remains to mature in the work speed when heavy images or large files are loaded; sure that in Linux it runs better, but not in Windows, and, a Strong challenge For convincing the world that the open is not to belittle.

3 There is CAD that already does GIS

In the case of Bentley Map and AutoCAD Map, the position has been to create GIS capabilities for the tools that were used for engineering. The advance has been significant, there is no doubt about it, but to date many visualization and publication functionalities (painted maps) are weak in what GIS does (or better) do. I also believe that the practicality of implementation for simple jobs is still ... Hair pull; if not, let's see how many users there are of AutoCAD (millions) and how many (that they would like) of AutoCAD Map (or Civil 3D); not because of price issues, because the comparison could be the same if we do it with users who use licenses in a pirated way. Almost the same behaves with Microstation and Bentley Map, without getting into aspects of publication and interoperability (please).

4 CAD and GIS are two different topics.

There is a (grounded) position that says that both topics are two specialized areas and that there will be no capacity to do both with the same tool; Part of that posture inherits our perception of a few years ago:

... CAD is for making accurate vectors and GIS for beautiful maps.

But this specialty stance, as standards have matured and been appropriated by non-free software, has lost rigidity, initiatives such as OGC on the GIS side, implementation of the concept Topology, use of the xml that advances to the BIM concept on the side of the CAD, among others, that have made the CAD not be seen as the drawing board but part of the work of real specialties (Architecture, Civil Engineering, Topography, etc).

The trend says that the specialty will not be in the software (CAD / GIS) but in the area of ​​application. To give an example, designing roads should be a specialty of software that does that, with the accuracy of CAD and capabilities to serve it to the programs that will use the axis to do cartography under a GIS context. Likewise, the shapefile should go down in history and the GIS data be a graphic or tabular representation of reality whose geometry can be edited from the GIS side, consult its attributes, know its connections to other data; while from the GIS side its wonderful representations, linking to data and being able to edit with the precision that CAD would.

But for that ... we are honestly far away, not because there is not Already formed, Small tools already do a lot of that, but you have to move the big brands of software to implement it in a practical way.

4 As I see it

I think for a while, we will continue using two programs to represent the same property: editing its vector in CAD, analyzing it in GIS and modifying it in both. In my opinion, many things we do we have loaded so much smoked that lost the simplicity of its use for practical purposes and technological marketing (a problem) has made forget the reason for human ingenuity (solving problems).

image42 The drawing board had its glory, because no one invented another way to make the drawings by hand, plus electric drafts were added but the systematization of their practice was not in the material of the table but in what we were doing there. The cartography was to make maps under systematized scale and relevance standards, we thought about printing it but we never doubted its use for human purposes.

We should not lose consciousness, because now technology should make things easier for us and promote the same USE. So, there should come a time when the investment stops being about formats, processors, pixels, labels and brands, to invest time in the reason for which they were created: YOUR USE. Product of it, as before, to dedicate ourselves to generate business, wealth and benefit for people.

But the idea is unreal, and in my opinion, the next 5 years, for the majority of projects of the level level raised at the beginning, we will continue to do things the same (see we do not end up doing it in Google Earth). And the CAD / GIS software producers:

  • On the ESRI side, maybe Let's see improvements In the ability of CAD construction, hopefully not have to re-learn to use the drawing table again.
  • On the AutoDesk side, popularize Civil 3D to make Mapping look like part of engineering. Idea that seems right to me.
  • On the Bentley side, promote PowerMap For low-priced CAD to have GIS capabilities, and perhaps to facilitate implementation smoothing.
  • On the side of low-priced software: Manifold, Tatuk GIS, Global Mapper, IntelliCAD, gain ground by doing what brand-name software does not do.

If the Open Source software (sustainable) crosses this barrier, surely we will all look back there, not only by the economic aspect (Which we have already seen), but by solving common problems (which it is already doing) and a more aggressive global marketing than piracy.

Pessimistic, maybe; deluded, sure. And you: How do you see it?

6 Replies to "CAD, GIS, or both?"

  1. hi Cesar

    What happens is that the coordinates of your survey to be UTM are equal to what there could be in 60 possible UTM areas of the world, so you can define which one you are in. Also, the Datum is the reference ellipsoid, to give you an idea, as if the WGS84 was at sea level and another Datum like the NAD 24 passed to 3,000 meters above, the site could be the same and at one point the heartbeat and Length is the same, but the distances projected on these two different spheroids are not equal. That is why the UTM system is often called "projected."

    To do it in ArcGIS, you right-click on the layer that you are interested in georeferencing and choose the "properties" option, then in the panel that appears you choose the "source" tab.
    There, there is a button to choose the "source", then you enter and there you will look for a projected system (UTM), then you choose the corresponding area and if you are in the northern or southern hemisphere.

    With this your file is georeferenced to the datum and respective zone.

    A greeting.

  2. Good morning, I congratulate him for the excellent blog that he handles, I tego a doubt I have converted a dxf file to shp my file in cad this georeferenced and in fact in the gis, that by some use arcgis 9.3, I appear the coordinates but as unidentified , I know that I should put the information of the datum and I know what it is, but I do not know how, I would like to know this since I searched everywhere on the web but I do not find a real answer, I would appreciate it very much, if you could answer my question, please be cordenadas utm With gsw84

  3. «» »Jose maria said: March 16, 2010 - 8: 36 pm
    how to pass a drawing in cad to arc gis or arc view »» »

    Resp: from autocad map you export shapes lines, polygons (creating topologies) and points.

    To solve the problems of topological errors in cad there are many erramients such as the drawing clenup of autocad map help to debug the cad files before export or their use as layers related to objectsdata or in shapes. Also in arcgis as in other software gis as the openjump there are topological validators in my case I use both taking into account that in arcgis is important the resolution xy (tolerance) and q that depends on the quality of the layer, with openjump we can look for polygons With holes or vertices at a minimum distance required smaller angles.

  4. From ArcGIS you load it as a layer, then you make it into Featureclass

  5. How to pass a drawing in arc to gis or arc view

  6. Hello

    I see that you speak from the expertise of a "CADISTA".
    First things already known: Both software have different orinetaciones.El know when using one or the other is things of the user. We do not intend to use a flat of a house (CAD) in a GIS that for me is a software of ANALYSIS more than one that made nice maps (for that this mapublisher or corel etc).

    The implementation of the topology concept on the side of GIS in the years of arcinfo seemed a good solution for the solution of topological errors. From the mythical Arc / Info, esri has those buttons that you talk about:

    -buttons that are used to create (lines, arcs, circles, polylines, points ...) Unless you talk about things you dislike:

    -buttons to edit (parallel, copy, move, rotate, extend ...) Those same ones have them unless you refer to something else.

    -A practical snap control ... «Let the lines that are at a distance of 10 m ... come together.» That? «To be cut where they intersect» ... That? «To extend an arc to intersect another» ... That? As in CAD then?

    On the other hand the desires of software integration go hand in hand with the activity of users, to me for example I call for a greater integration between ARCGIS Splus or Matlab for example ...

    I believe that for the construction of a GIS project, the flowchart for my seria: construction of vectorial base in CAD, alphanumerical database in ARCGIS, construction and analysis of images in ERDAS (that on the contrary I think that a CAD images are only of Background support and no data with information with is in the GIS) and modeling in ARCGIS.

    Since ARCGIS (from ARC / Info, UNIX at least) handles double presicion in the coordinates of the vectors, there would be no problem of loss of precision. So ONLY it is missing that CAD can solve TOPOLOGICAL errors and the union of GIS / CAD would be a honeymoon.

    However, all of that is in the field of software since in liveware, CADISTS will have to learn to manage their projects more ORDERLY (the rivers in one layer and the streets in another) I hate receiving CAD information with polygons that are not such, lines without topological continuity (only graphic), and arches that represent rivers in layers that represent streets….

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