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Scholarly Works (3 results)

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UC Santa Cruz Electronic Theses and Dissertations (2019)

Artists, musicians, writers and designers use tools to be creative, whether they are designing a personal opus or producing work for hire. There are many more people who are neither paid professionals nor historic geniuses, but who also enjoy being creative in a casual way. Can we design systems to help these casual users engage with their creative sides?

In this dissertation, I define and describe a genre of systems, "casual creators". Casual creators are interactive, generative systems in which the user explores a possibility space of artifacts, in a way that feels easy, pleasurable, and expressive. Casual creators do not provide the user with the total control of a "traditional" creativity tool like Maya or Photoshop. Instead, they empower the user with some combination of automation, generativity, surprise, or social/community features. Crucially, casual creators is not a genre of new systems, but a lens for looking at many existing (and emerging) systems that share these properties, including digital systems like Kid Pix and Spore, as well as non-digital systems like the Spirograph and Mad Libs.

Contemporary creativity theory provides clues about where creativity happens (’environmental’ and ’embedded'; theories of creativity), and when creativity happens (’flow’ theory, improv). These theories have already been used to design creativity-augmentation systems in the field of creativity support tools and computational creativity. This dissertation combines these theories of creativity with theories of interactivity and generativity, to anticipate and catalog common patterns that can be seen when a user is creatively exploring a generative space.

The dissertation concludes with an initial set of ten patterns, including patterns that emerge from technical aspects of the system’s design and others that emerge from the system’s position in a social environment. Along the way, a couple hundred systems that are casual creators in some way are noted and analyzed. The primary contribution of this dissertation is that the term "casual creators" (and its associated frameworks) has been shown useful for understanding existing and new systems, and that it has seeded a community of practice around such systems.

    Cover page: Casual Creators: Defining a Genre of Autotelic Creativity Support SystemsCreative Commons 'BY-NC-ND' version 4.0 license
    • Article
    • Peer Reviewed
    UC Riverside Previously Published Works (2011)
    Routing resources in modern FPGAs use 50% of the silicon real estate and are significant contributors to critical path delay and power consumption; the situation gets worse with each successive process generation, as transistors scale more effectively than wires. To cope with these challenges, FPGA architects have divided wires into local and global categories and introduced fast dedicated carry chains between adjacent logic cells, which reduce routing resource usage for certain arithmetic circuits (primarily adders and subtractors). Inspired by the carry chains, we generalize the idea to connect lookup tables (LUTs) in adjacent logic cells. By exploiting the fracturable structure of LUTs in current FPGA generations, we increase the utilization of the existing LUTs in the logic cell by providing new inputs along the logic chain, but without increasing the I/O bandwidth from the programmable interconnect. This allows us to increase the logic density of the configurable logic cells while reducing demand for routing resources, as long as the mapping tools are able to exploit the logic chains. Our experiments using the combinational MCNC benchmarks and comparing against an Altera Stratix-III FPGA show that the introduction of logic chains reduce the average usage of local routing wires by 37%, with a 12% reduction in total wiring (local and global); this translates to improvements in dynamic power consumption of 18% in the routing network and 10% overall, while utilizing 4% fewer logic cells, on average. Copyright 2011 ACM.
      • Article
      • Peer Reviewed
      UC Riverside Previously Published Works (2012)
      In floating-point datapaths synthesized on FPGAs, the shifters that perform mantissa alignment and normalization consume a disproportionate number of LUTs. Shifters are implemented using several rows of small multiplexers; unfortunately, multiplexer-based logic structures map poorly onto LUTs. FPGAs, meanwhile, contain a large number of multiplexers in the programmable routing network; these multiplexer are placed under static control of the FPGA's configuration bitstream. In this work, we modify some of the routing multiplexers in the intra-cluster routing network of a CLB in an FPGA to implement shifters for floating-point mantissa alignment and normalization; the number of CLBs required for these operations is reduced by 67%. If shifting is not required, the routing multiplexers that have been modified can be configured to operate as normal routing multiplexers, so no functionality is sacrificed. The area overhead incurred by these modifications is small, and there is no need to modify every routing multiplexer in the FPGA. Experiments show that there is no negative impact in terms of clock frequency or routability for benchmarks that do not use the dynamic multiplexers. © 2012 ACM.
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