1. More Graphics

2. Hit Testing Mouse clicked here What did I click on?

3. Hit Testing easygl does not know what you drew –“Immediate mode” graphics –Draws the pixels for a line, etc. –Does not remember the line! Hit testing: you must code –act_on_button_press (x, y, button_info) –What is closest to that (x,y)? Code demo … –Hit testing & highlighting

4. Milestone 2 Overview

5. Milestone 2 Interactive map visualization Open ended –Specification is loose  you fill in the details –Taught: basics of graphics, data structures and using OSM data For best solution: must learn more & come up with own ideas Different than (most) labs –Labs: apply what you have learned in lecture –Design: go beyond what you have been taught

6. Milestone 2: API Layers Two layers of database interface Layer 2: used in milestone 1 –Must visualize all data in this layer –Streets, street names, one-way, points-of- interest, features, … FeatureType = Park FeatureType = Building

7. Layer 1 API New layer 1 API –All OSM data –Less structure –Optionally can use to visualize more –E.g. subway stations –Requires reading OSM docs & experimentation

8. M2 Basic Requirements Visualize everything in the layer 2 (StreetsmapDatabaseAPI.h) API Click on an intersection for extra data Find button to locate intersections by name Load any map without recompilation Graphics must be fast & interactive Detail must not overwhelm user  key info understandable at each zoom / option level Challenge: user can find all the detailed info (somehow in some view) and the big picture is still clear

9. M2 Grading Basic features: 5/12 Responsiveness, usability, aesthetics: 4/12 –Sample challenge: display street names well Which streets to label at which zoom? How often to label along the street? Special feature(s): 3/12 –Display more information from layer 1 API? –More “clickable” features (streets, parks, …)? –More Find by name features? –Your ideas? Don’t hard-code: we will test many maps

10. Good Special Feature? Change colour scheme? –Pinkify button –Difficulty matters!

11. Graphics Proposal & Milestone 2 Starting a new project  make a proposal 1.Survey the landscape –Background research How do others make GIS’ interactive and detailed? What makes user interfaces intuitive? How fast must a UI be to feel interactive? 2.Make a plan –What will you do? –How will you use or differ from the background research? 3.How will you measure success? –Goals / Testing –Does the background research give you ideas here? Use credible research Never skip this step!