Ducky's InfoVis Project Proposal

Proposal specs

Participants

Only me, Kaitlin Duck Sherwood, ducky@csDELETEthisTEXT.ubc.ca

Description

I plan to do a Google Maps mashup that overlays semi-translucent images on Google Maps in order to show area-based data.

Personal expertise:

• I did a project integrating maps, floorplans, and a virtual walkthrough years ago at UIUC.
• I have investigated several maps/census schemes in the past 10 years, but never gotten past the exploratory stages.
• I am sort of aware of
• I have never written anything in Javascript before, nor any dynamic client-side code of any kind, but would like to learn.
• I am not a graphics whiz. I am not sure what algorithms to use to select what data is likely to be visible. OTOH, I have not only a copy of Foley and Van Dam, but also Google, within easy reach.
• This could be a really cool project.

Proposed solution

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Scenario

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Interface mock-ups

@@@ illustrations of what the interface will look like

Implementation approach

I plan to use Javascript and the Google Maps API to serve maps, capture pan/zoom events, and to overlay area data on top of the Google Maps.

I plan to use the gd library, probably with a perl wrapper, to generate a transparent PNG image to overlay on top of the maps.

I plan to use C language Shapefile C library to parse a variant of the TIGER/Line data -- the ESRI shapefile data.

@@@ library for dBASE files

Milestones

Include a list of project milestones with dates, breaking down the work into a series of smaller chunks.

Tasks (not milestones):

• Figure out how to overlay one png on static map
• Figure out how to overlay another png when map is recentered
• Figure out if Google Maps can overlay maps fast enough.

• Find good shapefiles
• Develop a simple test suite for PNG manipulation
• Write code to create PNG from one known polygon extracted from shapefile; overlay on Google Maps
• Write code to create PNG from several known polygons extracted from shapefile; overlay on Google Maps
• Write code to create PNG from several known polygons, shaded with data from dBASE file; overlay on Google Maps

• Given zoom level and map lat/long boundaries, figure out how to tell which polygons are visible
• Write code to retrieve a polygon based on lat/long.
• Write code to create PNG from lat/long boundaries at default zoom level
• Figure out how to aggregate data from multiple polygons
• Write code to aggregate data
• Modify code to create PNG from lat/long/zoom data
• Overlay images dynamically on Google Maps

• (aggressive) Add sliders to allow changing the parameters of the image (e.g transparency, hue)
• (aggressive) Add radio buttons to change data sets