PosadaSpace: a Skeletal Fine Art Virtual Environment

by Mike Mosher (mikemosh@well.com)
and Tim McFadden (tim.mcfadden@thinkone.com)


The 1998 artwork PosadaSpace is a virtual world exhibited in a decorated computer kiosk. Mike Mosher and Tim McFadden built it around the historic cartoon imagery of Jose Guadalupe Posada (and some other Mexican art) to investigate the appeal and narrative power of simple 2D sprites in defining and populating an interactive 3D world.

I. Preface:

In the spring and summer of 1998, Mike Mosher and Tim McFadden created a fine arts VR kiosk artwork called PosadaSpace. Mike designed its environments and component JPEGs, and painted an external facade for its computer. Tim programmed the world in VRML and JavaScript, as well as programming three predetermined paths for the viewer. This work however was the fruition of discussions between the two-an artist and a software engineer-dating back to the First Conference on Cyberspace in Austin, TX, in April 1990.

II. Aesthetic issues:

Art can be said to be the subtle manipulation of limitations. Mike has long held that too many 3D worlds remain kitsch, overly-complicated, overdetermined and overdesigned, splendidly serving to demonstrate the capabilities of a computer's hardware and software but little else. These interactive 3D virtual worlds could best be constructed not by attempting a debatable "realism" of every detail, but by emphasis on selected onscreen objects (sprites) and diminution of detail on others. Lessons are to be learned from the early low-resolution videogames like "Tank Commander" circa 1980, where the interactive experience is probably enhanced rather than diminished by the economy of visual information on the screen. The viewer's attention is thus focused upon a clearly-designed center. With more limited visual information the eye also better follows movement of a sprite. Limited visual information may also aid the viewer in spatially locating oneself as the viewpoint moves. Smoothness of navigation may give the greatest experience of real-world veracity, not the detail of rendering of the objects depicted. Low-resolution depiction on screen may have additional performance benefits (1), and economy of rendering might free up processing power to be better applied to responsiveness and refresh rate. For these reasons it was decided the team would create a 3D world containing 2D JPEGs, nearly-monochromatic cartoon figures standing like flat cut-outs. A visually appealing JPEG of a painting, drawing or photograph can be positioned vertically in a virtual world creates the metaphor of an environment with muralized walls.(2)

III. Content:

PosadaSpace used JPEGs of imagery drawn by José Guadelupe Posada (1852-1913), a hardworking illustrator for forty years of nearly 20,000 cheap, popular broadsides and handbills in Mexico City (3). He frequently used the motif of the calavera, or skeleton, to illustrate humorous social or political commentary. Skeletons were presented dressed in the garb of their owner's role when living-bishop, businessman, fashionable lady, Zapatista revolutionary, etc., or carrying on activities such as reading, eating, bicycling etc. They are visually simple yet powerful and memorable, as the best cartoons and comics artwork must be. (4). Posada was a significant inspiration for Diego Rivera and his generation of Mexican muralists and painters. Mike took the liberty of including Diego's wife the painter Frida Kahlo in the artwork, using Posada's busy skeletons and exaggerated figures as metaphor for the tensions within their marriage. Three tours through the PosadaSpace were designed in hopes in proximity they convey a certain evocative narration whose imagery links artists, love and death. The painted, cut-out facade designed to surround the computer in which PosadaSpace is exhibited is intended to give the work a certain carnival-ride attraction (5). Yet it is also hides or masks the machine, for if the computer is to become more a servant of daily life and become absorbed within other appliances it should certainly do so within artworks as well. It is hoped that works like this then take their place as part of a continuum of complex narrative figurative artwork that includes the architectural frescoes of Michelangelo and Rivera, rather than inhabitant of a separate category "computer art".

IV.The Three Tours

The first tour carries the viewer from an opening "gateway" with a portrait of Posada, he title and explanatory paragraph hovering in space to a "sculpture garden". The viewer moves between the sprites in a sort of star pattern, moving close to investigate each one. Two walls that share a vertex to form a corner are fairly ornate, one having Rivera's "Dream of a Sunday Aftertoon in Alameda Park" mural (which alludes to Posada's calaveras ) mapped upon it, for a free-standing complex graphic image becomes a muralized wall within the architecture of cyberspace.

The second path moves from the gateway towards the sculpture garden, then veers sharply to the left where it moves towards what appears to be a gravestone or monument. The viewer then descends, the visible walls of the "elevator" proving to be Diego Rivera's mural of millionaires dining. Upon reaching the bottom, the viewer turns to see "Frida's Boudoir", her portrait upon a bed-like floating rectangular object. A bust of Russian revolutionary Leon Trotsky, murdered in exile in Mexico, stands beside it. Images from a "Mexican Art" disk of clip art, of several women drawn by Rivera, were positioned to serve as the walls of Frida's boudoir. This imagery alludes to the fact that Frida Kahlo had a love affair with Trotsky as well as with several women, and Diego had affairs with many women that he painted. The third path takes the viewer to the frontiers, where four Posada images of crowds among buildings appear, finally shooting the viewer upwards to view close-up a moon-like rotating sphere with a crazy face mapped upon it.

V. Engineering Issues:

Tim McFadden relished the opportunity of this project as a great way to learn the languages VRML and JavaScript. In something resembling a movie's director-cameraperson relationship, Mike designed the scenario's storyboard and look and feel of the project while Tim performed the coding. "For a programmer, it was a big thrill to be in control of moving bodies in color" said Tim. Most of the VRML was hand coded, but for creating the navigation paths a table-driven curve generator was written in C. A table would specify start and endpoints, type of curve, rotation, and initial value for splines. The output of the C program would be loaded into MFVec3f arrays in a JavaScript node to be loaded sequentially into eventOut SFVec3f and SFRotation fields on clock ticks. The spline code camedirectly from William Press' Numerical Recipes in C.

VI. Process Issues:

Mike Mosher handed over to Tim McFadden specifications for PosadaSpace, including sketches of proposed positioning of the sprites and the trajectory of the viewer's paths through the world. Upon viewing the results notes on their modification would be presented in action item lists. For an artist and a software engineer to work together efficiently meant a learning process towards a common language, so visual ideas which Mike would otherwise express evocatively yet imprecisely could be quantified for the most precise implementation by Tim. By assigning numerical values to the position of each sprite, Tim could build paths that most accurately resembled Mike's intentions, and then together they could refine them upon viewing of the results in thebrowser.

VII. Further Development:

The initial version of PosadaSpace was exhibited upon an Intergraph workstation in "The Art of Digital Technology", an exhibit curated by Barbara Allie and Barbara Rainforth held at the Santa Clara County Fair in August 1998. All visual development on PosadaSpace had to cease in mid-July prior to Mike's travels (6); coding, of course, continued up until the last possible minute. It was exhibited behind a 4' x 2' painted facade of two skeletons kissing, with another skeleton on each 18"- wide side wing panel. There were significant difficulties encountered with the browser, requiring positioning a strip of black tape on the screen and Tim clicking at precise moment to stop its rotation. It is also suspected the piece may have been down (frozen or shut off) a considerable amount of time during the exhibit. Work has begun on refinement of the Tour paths, with the addition of one or more new Tours under consideration. The optimum goal would be to allow the user total freedom to wander, yet worlds built in this manner traditionally suffer the problem of the user flying out into empty space without sufficient visual clues that allow easy return, unless an invisible bounding box or sphere is in place.

Tim has begun to code PosadaSpace to swap high-resolution JPEGs for conventional ones when the viewer reaches a predetermined distance from a specific JPEG. A later version will use LOD. This would give the illusion of near focus without big pixels' blockiness interfering with reading of the image. Some of the animated movement within the world could not be implemented, due to the browser slowing down. In three instances the swapping of alternatives to specific sprites, so skeletons would appear to strum a guitar or stab a piece of meat with a fork. However tthe standing portrait of Posada by Rivera would momentarily momentarily swap with a version wearing a skeleton head, and a large moon face mapped upon a sphere above him would rotate. The tale of Indra's Net says that the universe is made of an infinite net at whose intersections are jewels, each jewel reflecting all the others. With this image engaging him as a provocative paradigm of cyberspace, Tim hopes to continue the work within it begun in his essay "Notes on Cyberspace and the Ballistic Actors' Model" (7) both in writing and embodied in future collaborative art projects. Tim did not have access to a Java-compliant VRML browser early enough in the PosadaSpace project, but in the future hopes such projects will be networked and multi-user. It is hoped by both Mike and Tim that continued development of VRML, and supportive technologies like MPEG-4, will support continued investigation by many more teams of artists and programmers, pursuing their personal investigations into design and content amidst the burgeoning potential of creative virtual worlds.


(1) First proposed by Mike Mosher in "Objects in Mirror May Be Larger: On Designing Low-Rez Virtual Worlds" a poster installation at the Second Conference on Cyberspace, Santa Cruz CA, 1991.

(2) Mike's experience painting murals in San Francisco,and living in its mural-rich Mission neighborhood 1981-84, inspires this direction.

(3) Berdecio, Robert and Applebaum, Stanley, Posada's Popular Mexican Prints (Dover Publications, New York NY, 1972), Preface and Acknowlegements.

(4) When Tim wore a Posada calavera t-shirt to a breakfast meeting at Hobee's Restaurant, Mountain View, in February 1998 Mike realized the appropriateness of Posada's simple,powerful imagery for their first virtual world.

(5) Two recent public sculptures in Mountain View, California that are larger-than-life cut-out figures in metal by Joe Sam stand at the City Hall and at the Whisman Sports Center. Mike acknowleges the influence of works like this upon PosadaSpace's "sculpture garden". Mike painted mural panels in 1990 for Laguna Honda Hospital, San Francisco, cut to the contours of the composition of multiple figures, and since 1992 has exhibited multimedia and hypertext software in kiosks whose screen is cut into shaped, painted facades.

(6) While in Memphis TN in August 1998, Mike organized and painted a collaborative mural panel "Transistor Healing Elvis", described in "Elvis Healed! A Report From His Conference" in BAD SUBJECTS #39 (HTTP://eserver.org/BS/39) .

(7) Published in Benedikt, Michael, Cyberspace: First Steps (MIT Press, Cambridge MA 1991).


Anders, Peter, Visualizing Cyberspace (Macmilliian and Co., New York NY, scheduled 1/99). Includes mention of PosadaSpace plus a screenshot.

Bad Subjects Production Team, Bad Subjects (NYU Press, New York NY, 1998). Includes Mike Mosher's essay "Towards Community Art Machines".

Benedikt, Michael, Cyberspace: First Steps (MIT Press, Cambridge MA 1991). Includes Tim McFadden's essay "Notes on the Structure of Cyberspace and the Ballistic Actors Model".

Berdecio, Robert and Applebaum, Stanley, Posada's Popular Mexican Prints (Dover Publications, New York NY, 1972).

Carey, Rick and Bell, Gavin, The Annotated VRML 2.0 Reference Manual (Addison-Welsey Publishing Co., Reading, MA, 1997). Tim found this book especially a joy to read and use.

Press, William et. al., Numerical Recipes in C (Cambridge University Press, Cambridge UK, 1988).

Rothenstein, Julian, J. G. Posada: Messenger of Mortality (Moyer Bell Limited, Mt. Kisco, NY, 1989).

Mike Mosher is an Adjunct Professor in the University of San Francisco College of Professional Studies Information Systems Program, Cupertino, California U.S.A.. He has taught in the San Francisco State University Art Department, the SFSU Inter-Arts Center and the SFSU Multimedia Studies Program. His multimedia artwork has been exhibited at the Franklin Institute in Philadelphia, the Rochester Institute of Technology, and Artists' Television Access in San Francisco.

Tim McFadden is a software engineer at ThinkOne, Brisbane, California, U.S.A., where he is currently networking MPEG-4. Please note that PosadaSpace is unrelated to any work done by Tim for ThinkOne, and does not in any way represent the efforts of ThinkOne in VRML or MPEG-4. Tim is also working privately on a sonar cyberdeck, and will continue to develop fun art to upload into cyberspace.

Mike Mosher and Tim McFadden would like to thank Barbara Allie and Barbara Rainforth for exhbiting PosadaSpace in the Art of Digital Technology exhibition, and Trudy Reagan for help with its installation there.

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