The OpenStudio project began in 2006 as a direct-to-EnergyPlus plug-in for the 3D drawing tool SketchUp. SketchUp’s popularity—and the fact that it was free for commercial use—helped EnergyPlus find a footing in the industry and spurred further OpenStudio development. When Trimble Navigation acquired SketchUp and began charging for commercial use, BTO “froze” the OpenStudio SketchUp plug-in and began looking for a free and open source strategy for creating energy modeling geometry input. That strategy debuted in the recent OpenStudio 2.3.0 release.
OpenStudio application users may have noticed a new geometry tab with an embedded graphical 2D floor-plan editor. Called FloorspaceJS, this new editor was developed by Denver based web-software shop Devetry. FloorspaceJS is grid based and resembles the BEopt geometry editor and supports story-by-story floor-plan definition and extrusion. It is “aware” of spaces, thermal zones, and other energy modeling concepts. A modeler can draw on a clean sheet, or over imported floor-plan images, maps, and drawings of previous stories. She can label interior spaces, assign space types, and collect spaces into zones. She can also assign surface constructions and properties such as outdoor boundary conditions and place doors, windows, shades, and daylight sensors. Features like multi-story spaces, skylights, pitched roofs, and PV will be available in follow-on versions, allowing FloorspaceJS to support many BEM projects. Designs with more complex geometry elements like pitched walls, non-rectangular windows, or non-perpendicular shading devices, can be created in full-featured CAD or BIM geometry authoring tools and imported into OpenStudio using gbXML. The modeler can view pan, zoom, and rotate both FloorspaceJS and imported geometry in 3D using OpenStudio’s View Model Measure.
Second, FloorspaceJS transitions away from integrated geometry editing towards an “import-merge” interaction model. OpenStudio does not interact with FloorspaceJS while the modeler is editing. Instead, OpenStudio “imports” the JSON file when the modeler saves the drawing, translating it to its own internal “2.5 dimensional” geometry representation. OpenStudio uses space and zone name tags to “merge” geometry changes with its internal model without losing track of non-geometry information like schedules and HVAC systems, supporting iterative geometry editing. OpenStudio already uses “import-merge” in gbXML, IFC, and GeoJSON based geometry workflows. Unifying “embedded” geometry editing with this path allows the OpenStudio development team to focus on a smaller, simpler set of capabilities, leaving geometry editing—especially the 3D variety—to other developers.
With FloorspaceJS up and running, the OpenStudio SketchUp plug-in will be deprecated over the next several releases. BTO hopes that, like its predecessor, it finds a new home.