An occasional sampling of reader electron-mail, or "keep those waves and particles pouring in, folks!"

DEPARTMENT OF CORRECTIONS: As part of the LLetter's ongoing dialog about Building Information Modeling (BIM) we referred in IssueNineteen's LLLetters to an Autodesk Revit white paper (PDF) and its alleged "spirit of Revit white papers from that product's previous life in the independent Revit Technology Corporation (RTC)"—which we further characterized as seeming "to fly perilously close to a gray zone that [we] call revitas—which contains the same elements as veritas (the truth), just slightly scrambled."

> This opinion was repeated by Martyn Day in IssueTwenty, albeit without our original disclaimer: "As a corporate entity, Autodesk adheres to the highest standards in its public statements, and [we] would be confident that any lingering ambiguities in the Revit white paper will soon be rectified."

> Subsequently, Autodesk's legal department asked us to identify any instances of "revitas" remaining in the white paper so that they could be corrected. We are happy to report that a close re-reading of the latest version of the white paper reveals it to be, indeed, revitas-free. We apologize to the fine folks at Autodesk for any prior misunderstanding.

DEPARTMENT OF CORRECTIONS, PART DEUX: Jan Erik Stoll of Consistent Software (International) of Norway writes:
> "PlanTracer and Plan 2 Model are developed by Consistent Software (International) from Norway, not Consistent Software of Irigny, France, as you mentioned on your web site [IsuueTwenty-One's LLemma]."

> We regret the error and apologize to Mr. Stoll and to Consistent Software (International) of Norway. For the record, we said that Consistent Software (International)'s excellent technology for recognizing patterns (such as columns, walls and doors) in vector drawings is marketed by scanner vendor Ideal as PlanTracer—for AutoCAD output (Ideal also is the US marketer for Consistent's WiseImage raster editing and raster/vector conversion tools and RasterID title block extraction software)—and that Consistent's technology also underlies ArchiCAD vendor Graphisoft's super-slick Plan2Model, which quickly and easily converts plans from any 2D CAD vector-file format to intelligent 3D ArchiCAD building information models. This is important technology because it allows facility owners/managers to liberate their building information from dumb, flat legacy file formats.

DEPARTMENT OF CORRECTIONS, PART C: Landscape architect Barbara Simpson, responding to a point in IssueEighteen's LLemma—Ad BIMinem Argument writes:
> "Mr. Laiserin, You state 'CAD we've known rarely if ever supported schematic design.' This statement does not reflect my work experience at all. As a Landscape Architect I now do most of my schematic design work on [Auto]CAD or Microstation. Also, the acronym 'BIM' sounds a little goofy—kind of like BIMBO without the BO."

> Sounding "goofy" is not the worst thing in the world. By the way, "BIM" need not be pronounced as if it were a word, but could be spelled out—"B-I-M"—as many folks, especially in the UK, still spell out "C-A-D" in conversation.

> To be sure we were describing the same thing when discussing "schematic design," I asked Ms. Simpson what tasks were included in "most of [her] schematic design work," to which she replied:

> "In the schematic phase the work is exploring site layout, pedestrian circulation, parking alternatives, building siting, conceptual grading and drainage alternatives, cut and fill options and relative quantities, planting areas, and open structures such as bus and train station shelters—but not detail work. With CAD it is possible to explore many schemes quickly and accurately, decide on feasibility and then go directly into production with the selected alternative. The other advantage is that schematic alternatives can be forwarded between offices to communicate ideas (although faxing hand drawn sketches still occurs frequently as well). The architects and tunnel and bridge engineers I work with also often explore structure styles, treatments and massing in 3-D early in the schematic phase to show to clients and the public.

> Hmmm? Other than that, not much, eh? —I not only stand corrected, but extremely impressed as well. There is no question that a skilled designer who has taken the trouble to master and integrate the available tools—as Ms. Simpson obviously has—can indeed make "the CAD we've known" work for schematic design. Perhaps my original statement should be amended to read: "the CAD we've known has not easily supported schematic design, except in the hands of skilled and determined users."

DEPARTMENT OF CORRECTIONS, PART IV: Hugo da Cunha, Senior Design Architect with Clive Fredman & John Malina Architects in Caulfield, Victoria, Australia, writes:
> "It is always with great interest that we in the Office read your articles. Keep up the good work.

"We ended up buying ArchiCAD R.7 and are now looking forward to upgrade to R.8. So far so good. We found out that Architect Frank Gehry uses in his office a powerful 3D software called CATIA. Out of curiosity, have you any articles about it?

"Our kindest regards from Down Under."

> Thank you for the kind word, Hugo (even though it's not a correction) and congratulations on your success with ArchiCAD and its 3D "virtual building" implementation of BIM (Building Information Modeling). Regarding CATIA, we have not had the privilege of reviewing it. However, Gehry's firm is one of the few applying this industrial design tool to the design of buildings (and CATIA is not the only design software that Gehry Partners uses). With the recent spin-off of Gehry Technologies to evangelize Gehry Partners' working methods, long-standing rumors of a future "AEC flavor" of CATIA have gained in credibility. We'll keep you posted here in the LLetter if and when there is more news on this front.