Loading ...
Sorry, an error occurred while loading the content.

Review of a new computer tool

Expand Messages
  • Christopher Miller
    For those interested in urban design tools, a review of CityCAD software at Planetizen: http://www.planetizen.com/node/39940
    Message 1 of 1 , Aug 3, 2009
      For those interested in urban design tools, a review of CityCAD
      software at Planetizen:



      Visualizing and Analyzing Plans with CityCAD

      30 July 2009 - 9:00am
      • Charles A. Donley, AICP
      Planning technology expert Charles A. Donley reviews a new piece of
      software that combines the worlds of Computer-Aided Design and
      Geographic Information Systems to help site planners visualize and
      analyze their plans.

      CityCAD is a conceptualization tool for urban design. The standalone
      software integrates simple drawing tools with impact analysis. CityCAD
      combines elements of Geographic Information Systems and Computer-Aided
      Design, targeting the interests of site planners without a lot of
      extraneous features and functions.

      CityCAD offers a tool for exploring urban design concepts and
      evaluating the impact of a plan. You can design streets, massing, and
      density while concurrently calculating floor areas, costs, emissions
      and other factors.

      The main display of CityCAD.
      The CAD acronym in the product name acknowledges the software
      developer’s orientation: they wanted a simple design tool. But they
      also wanted a smart tool to measure the impacts of a project: this is
      GIS. The software is a hybrid of GIS and CAD, wisely adapted to urban
      design, yet there is little acknowledgement of the GIS relationship.

      But the software approaches the CAD-GIS hybrid in a user-friendly way.
      Users sketch in streets to define blocks, assign land uses and
      densities, and then identify potential impacts in real time. CityCAD
      automatically generates a plan based on user defined design standards.
      A simple street centerline generates pavement, sidewalks, setbacks and
      trees from a selected cross section. Relocating the centerline
      recalculates the block area, dwelling units, non-residential space,
      and the associated impacts. Resetting density, unit dimensions or
      total units recalculates the other parameters.

      Project drawing is done in a simple 3D perspective view, an important
      feature for those unskilled in translating a flat map into the real
      world. The resulting image is cartoonish, not photo real. Creating
      more complex geometry requires imports from other software such as
      AutoCAD or SketchUp.

      CityCAD can import AutoCAD files, but the typical complexity of CAD
      drawings limits their usefulness in this decidedly less sophisticated
      software. If you have a CAD drawing that you’d like to use, it may
      make more sense to import only a few basic elements. For example,
      maybe you just import the street centerlines, eliminating most of the
      lines, points and labels. Alternatively, you could import a site plan
      as an image and digitize in the streets. The drawing process in
      CityCAD is quick and intuitive.

      Better yet, use CityCAD’s tools for conceptualizing the plan from
      scratch. A range of standard graphic elements can identify edges,
      landmarks, nodes, and linkages. You can then draw the streets by type,
      thereby defining the blocks and review the resulting impacts. CityCAD
      also allows you to refine the design standards and layout to achieve
      the desired results. Ideally the design process could begin with a
      georeferenced aerial photo to illustrate existing conditions.

      The software has a British orientation as evidenced by the urban
      design features, default unit of measures and the accents in the
      tutorial (not that that is bad). You can adapt the software to many US
      standards -- and most urban design principles are universal. But my
      initial results still have a UK feel to them.

      For example, I would like to see an automated method for depicting
      detached buildings with sloped roofs, such as single family units or
      townhomes. Breaking up a building around the entire perimeter of a
      block involves importing CAD drawings or manually editing individual
      structures. Adding inputs to the detached block category could include
      building separation, number of units per building and maybe roof
      slope. This will greatly expand the software’s usefulness in the U.S.

      Below are some of the analysis tools that would be of most use to

      • Impact analysis topics include energy consumption, water demand,
      trash generation, parking spaces, and CO2 emissions. The quality of
      life topics expand with a couple clicks.
      • Appraisal tools identify project costs and revenues. Adding the
      phasing function can produce a great, draft project pro forma.
      Developers can quickly explore the cost and revenue of multiple
      scenarios. The Triggers highlight infrastructure concurrency issues.
      • Livability measures residential proximity to community facilities
      (e.g. bus stops or schools). The analysis uses straight-line distance,
      which can be misleading in areas with poor pedestrian circulation.
      Future versions should consider measuring the routed distance (e,g,
      following sidewalks). I understand this is a very complex feature, but
      straight line just does not represent reality.
      • Activity is a cool analysis tool that depicts daily patterns of
      land use activity. The problem with Activity tool is you must assign
      the hours of operation for each activity, a time consuming effort, but
      perhaps there is a work around. The Holistic City website includes 10
      project downloads including Central Park in New York. Marketing to the
      US market could benefit from another US project with the multipliers
      and factors adjusted to US standards. This includes land uses
      completed with activity settings; dollars, acres, and gallons as units
      of measure; and typical appraisal values. New users could explore the
      software results and start editing the values. Then they could delete
      the layout and start their own design with the US standards already in
      The new version also adds a route and tree manager. Creating a
      customized street cross section from a simple centerline is powerful.
      But I wonder how you deal with turn lanes.

      Rather than list all the functions and techniques, I encourage you to
      watch the video tutorials at http://www.holisticcity.co.uk/citycad/onlinehelp/
      . In an hour you will gain a good feel for the components and basic
      operation. An 8 hour trial version is also available. Then release
      your creative energies to decide how CityCAD can benefit your
      professional practice.

      CityCAD targets neighborhood-level design. Current computer processors
      would struggle with an entire city. The drawing tools lack the
      complexity to explore architectural details. You can try to do more,
      but the sweet spot is probably 4 to 40 blocks.

      The usability is good. It took me a couple hours to make sense of the
      software, but I may be more modeling- and technology-oriented than
      most planners. The button count at start-up is on the high side and
      some buttons are unnecessary for first time users. There is no Apple

      The Help suggests the user can customize the model with AutoCAD
      imports and XML code, but I refuse to accept the challenge. As a
      planner, I want technology to work right out the box.

      Relatively young software (first release, June 2008) typically
      contains many bugs. I found only one bug (start errors with Vista
      operating system are addressed in Help). The software is not built as
      an extension of other software (AutoCAD or ArcGIS), so it is not
      subject to changes in the parent software. My experimentation with
      CityCAD was limited and simplistic, but Holistic City seems to have
      stable product. Regardless, be forewarned that your creative
      application of CityCAD may find new issues.

      For planners looking to integrate GIS-based analysis into their
      existing CAD drawings, CityCAD offers a fairly straightforward option.
      It allows users to easily explore urban design concepts and understand
      how plans will play out once in place – two critical activities that
      have been compartmentalized too long.

      Charles A. Donley, AICP is an urban planner who specializes in
      applying technology to planning issues. Chuck is president of Donley &
      Associates, where he has worked on projects nationally and
      internationally. Chuck brings 25 years of experience in public and
      private sector planning, working on current and long range processes.
      As Technical Director for CommunityViz, he guided training,
      professional services, technical support, and software development.

      Chuck is also the instructor of a variety of instructional Planetizen
      webinars, teaching planners such technologies as Google Earth,
      SketchUp, CommunityViz, and GIS concepts. Learn more athttp://www.planetizen.com/courses


      Christopher Miller
      Montreal QC Canada
    Your message has been successfully submitted and would be delivered to recipients shortly.