Computational Geometry and Geographic Information Systems · HIT
CG

0-66122 · HIT · Elective Course · Semester B · Year of Study 2025

Computational Geometry and Geographic Information Systems

גיאומטריה חישובית ומערכות מידע גיאוגרפי

GIS concepts taught through computational geometry primitives, spatial data structures, and map algorithms

Course work: semester GIS project with three student presentations Downloads: HIT catalogue DOCX files

HIT Catalogue Documents

Downloadable DOCX catalogue documents for course approval and publication.

About This Course

This elective combines Geographic Information Systems knowledge with the computational geometry primitives that make GIS systems work. Students learn GIS as an integrated system for capturing, storing, managing, querying, analyzing, visualizing, and communicating spatial information. Core GIS concepts such as maps, coordinate systems, projections, vector and raster layers, terrain, imagery, geodatabases, cartography, and web maps are taught alongside the geometric representations and algorithms behind them.

The course treats every GIS topic as both an application and a computation. A parcel layer becomes a set of polygons; a road network becomes a graph embedded in the plane; a terrain model becomes a triangulation or raster surface; an orthophoto becomes georeferenced imagery; a spatial query becomes a geometric predicate, index lookup, or range search.

The goal is for students to understand GIS practice and the computer-science foundations underneath it: robust geometric primitives, spatial predicates, planar subdivisions, triangulations, nearest-neighbor search, range queries, map overlay, spatial indexing, shortest paths, approximation, and scalable map processing.

Maps As GeometryGIS layers represented as points, polylines, polygons, rasters, grids, surfaces, and planar subdivisions.
Coordinate FoundationsMap scale, geodesy, datums, projections, coordinate systems, and the computational consequences of spatial reference choices.
Geometric PredicatesOrientation tests, point-in-polygon, segment intersection, topology checks, containment, adjacency, and map validation.
GIS AlgorithmsConvex hulls, triangulation, Voronoi diagrams, Delaunay triangulation, map overlay, polygon clipping, and simplification.
Spatial Data StructuresQuadtrees, k-d trees, R-trees, geodatabases, range queries, nearest-neighbor search, and spatial joins.
Applied GIS SystemsCartography, symbology, GPS, LiDAR, aerial photography, remote sensing, orthophotos, web maps, and routing.

Course Objectives And Learning Outcomes

By the end of the course, students will be able to explain GIS as a complete spatial-information system, connect GIS knowledge with computational geometry primitives, and use that connection to design, explain, and evaluate spatial analysis workflows.

1SExplain GIS as a system: spatial data capture, storage, management, querying, analysis, visualization, and decision support.
2MRepresent GIS layers as geometric data: points, polylines, polygons, rasters, grids, and terrain surfaces.
3CExplain how scale, projections, coordinate systems, datums, and geodesy affect spatial computation.
4PUse geometric primitives, predicates, and orientation tests to reason about spatial objects.
5IApply point-in-polygon tests and line-segment intersection methods to containment, crossing, and layer-cleaning tasks.
6TUse triangulation, Voronoi diagrams, Delaunay triangulation, and TIN models for proximity, terrain, and interpolation contexts.
7XDescribe map overlay, polygon clipping, and planar-subdivision operations behind layered GIS analysis.
8DCompare quadtrees, k-d trees, R-trees, and geodatabase indexes for spatial query workloads.
9QAnalyze nearest-neighbor search, range queries, spatial joins, and routing queries in map data.
10VUse cartography, symbology, simplification, image pyramids, and tiled maps for scalable GIS visualization and communication.

Semester Project

The running project is the center of the course. Each team chooses a GIS problem, represents the data geometrically, and applies computational geometry primitives or spatial data structures to solve it. The project should include a real or realistic spatial dataset, a clear GIS question, explicit geometric representation choices, at least one core algorithmic method, and a final map, query workflow, prototype, or analysis artifact.

Teams may use QGIS, PostGIS, GeoPandas, Shapely, CGAL, Python, JavaScript mapping libraries, or another approved toolchain. The point is not tool volume; it is the ability to explain the GIS meaning, the geometric model, the algorithmic method, and the limitations of the result.

P1Student Project Presentation 1 · Proposal

20% of the grade · week 5 · problem, data, representation, and plan

P2Student Project Presentation 2 · Interim

30% of the grade · week 8 · working foundation and spatial-method review

P3Student Project Presentation 3 · Final

50% of the grade · week 13 · complete project and oral defense

Example Project Ideas

Each idea below combines GIS knowledge with computational geometry. Teams may take one as-is or propose a variant of comparable scope.

PParcel containment checker. Test whether addresses, trees, incidents, or sensors fall inside parcel, zoning, or municipal polygons using point-in-polygon and topology validation.
OLand-use overlay analyzer. Combine zoning, flood-risk, land-use, or infrastructure layers using polygon clipping and map overlay operations.
NNearest facility service areas. Use nearest-neighbor search, Voronoi regions, and distance measures to assign demand points to clinics, schools, shelters, or transit stops.
TTerrain and elevation model. Build or analyze a TIN or triangulated surface from elevation points, then visualize slope, drainage, or visibility patterns.
RRoute and reachability planner. Model roads, paths, or utility lines as spatial networks and compute shortest paths or reachable areas.
ISpatial index benchmark. Compare brute-force search with quadtree, k-d tree, or R-tree indexing for range queries, spatial joins, or nearest-neighbor tasks.
SMap simplification tool. Simplify road, boundary, or coastline geometry for multiple zoom levels while preserving shape quality and topology.
MImagery-derived feature map. Use aerial or satellite imagery outputs as GIS layers, then analyze geometry, proximity, area, or spatial distribution.

Weekly Materials

Each week combines the in-class plan with a study trail: lecture focus, practice brief, videos, official documentation, tutorials, and readings. In weeks 5, 8, and 13, the practice slot is a Student Project Presentation.

Weekly plan, lecture focus, and practice focus
Part I · GIS Concepts As Geometric Objects

Week 1GIS layers, maps, and geometric representation

LectureMapping technologies, map scale, vector layers, raster layers, thematic layers, image layers, and GIS as geometric data.
PracticeInspect GIS layers and classify each dataset as points, polylines, polygons, rasters, grids, or surfaces. Define possible semester project domains.
Reading QGIS Training Manual, course introduction and creating a basic map.Tutorial Introduction to QGIS.

Week 2Coordinate systems, projections, and robust predicates

LectureGeodesy, datums, projections, coordinate systems, spatial reference systems, orientation tests, sidedness tests, and degeneracies.
PracticeTransform sample coordinates, compare projected and geographic coordinates, and implement basic orientation and distance predicates.

Week 3Containment, crossing, and topology in vector GIS

LecturePoint-in-polygon tests, ray casting, winding number intuition, segment intersection, parcel containment, network crossings, and topology cleaning.
PracticeImplement point-in-polygon and segment-intersection checks on small parcel, road, or zoning examples.

Week 4Spatial extent, convex hulls, and bounding geometries

LectureSpatial extent analysis, bounding boxes, convex hulls, monotone chain or Graham scan, geographic envelopes, and point-cloud summaries.
PracticeCompute bounding boxes and convex hulls for sample GPS or facility datasets. Prepare project proposal materials.
Part II · Geometric Algorithms For GIS Analysis

Week 5Project proposal presentations, terrain, and triangulation

LectureDigital terrain models, TIN surfaces, polygon decomposition, triangulation, elevation data, and surface representation.
Practice · Project PresentationProposal presentations. GIS problem, dataset, representation, geometric primitive, and planned implementation.
Reading CGAL 2D triangulations.Tutorial QGIS raster module, for terrain and elevation context.

Week 6Proximity GIS, Voronoi diagrams, and Delaunay triangulation

LectureNearest facilities, service areas, proximity regions, Voronoi diagrams, Delaunay triangulation, interpolation intuition, and facility-location examples.
PracticeBuild a proximity analysis for service points or sensors, and relate Voronoi cells to GIS service areas.

Week 7Map overlay, polygon clipping, and planar subdivisions

LectureLayer intersection, polygon clipping, overlay analysis, planar subdivisions, arrangement intuition, and combining thematic GIS layers.
PracticePerform an overlay workflow such as land-use by municipal boundary, buffer by parcel, or environmental zone by road corridor.
Part III · Scalable GIS Queries And Map Systems

Week 8Interim project presentations, geodatabases, and spatial indexing

LectureGeodatabases, spatial database queries, quadtrees, k-d trees, R-trees, bounding boxes, indexing tradeoffs, and map-query acceleration.
Practice · Project PresentationInterim presentations. Prototype, data representation, spatial query strategy, early results, and next steps.

Week 9Spatial queries, nearest neighbors, and remote-sensing layers

LecturePoint location, window queries, proximity search, spatial joins, GPS observations, LiDAR point clouds, imagery-derived features, and query complexity.
PracticeImplement or configure a nearest-neighbor, range-query, or spatial-join workflow using project-style data.

Week 10Spatial networks and shortest paths

LectureRoad networks, graph models embedded in space, shortest paths, routing, network costs, and spatial constraints.
PracticeModel a small road, pedestrian, or utility network and run a routing or reachability analysis.

Week 11Cartography, symbology, and geometric simplification

LectureCartographic communication, symbology, labeling, scale-dependent detail, line simplification, polygon simplification, and geometric approximation.
PracticeSimplify a map layer, compare geometry quality across scales, and design a readable project map.

Week 12Web maps, imagery integration, and scalable spatial products

LectureImage integration, mosaics, orthophotos, image pyramids, tiled web maps, spatial APIs, and scalable geometric processing.
PracticePrepare final project maps, figures, query outputs, or prototype demonstrations for presentation.

Week 13Final student project presentations

LectureCourse synthesis: GIS knowledge, geometric primitives, spatial data structures, and map algorithms as one design vocabulary.
Practice · Project PresentationFinal presentations. Completed project, GIS interpretation, computational-geometry explanation, evaluation, limitations, and demonstration.
Reading Review selected project-relevant sections from the QGIS Training Manual, PostGIS workshop, and computational geometry references.Tutorial Final project documentation, map export, and oral defense rehearsal.

Video References

These video resources support the weekly plan. English materials are the primary watch list; Hebrew materials support review, terminology, and local context where a relevant source exists.

English Videos

English GIS
Introduction to Geographic Information Systems · YouTube playlist

Useful for GIS components, vector data, topology, raster data, and introductory spatial analysis.

English GIS
Learn GIS: QGIS Full Course for Beginners · YouTube

Practical GIS workflow support for data loading, layer inspection, styling, and map production.

English CG
Computational Geometry · NPTEL playlist

Algorithmic support for line sweep, visibility, triangulation, Voronoi diagrams, and geometric searching.

English CG
Computational Geometry · Philipp Kindermann

Concise lecture sequence beginning with convex hulls and other core geometric algorithms.

English QGIS
QGIS Coordinate Reference Systems and Projections · YouTube

Direct support for week 2 on CRS and projection choices.

English QGIS
Count How Many Points In An Area In QGIS · YouTube

Direct support for week 3 point-in-polygon analysis.

English QGIS
Voronoi Polygons in QGIS · YouTube

Direct support for week 6 proximity GIS and Voronoi regions.

English QGIS
QGIS Network Analysis: Shortest Path and Service Area · YouTube

Direct support for week 10 routing and spatial networks.

Hebrew Videos

Hebrew GIS
קורס GIS, שיעור 1: מבוא · YouTube

Hebrew introduction to GIS concepts and terminology.

Hebrew GIS
קורס מערכות מידע גיאוגרפיות GIS · Elevify

Hebrew GIS course page covering spatial data types, coordinate systems, cartography, and analysis topics.

Hebrew CG
יחידה 1: מבוא, מהי גיאומטריה חישובית? · YouTube

Hebrew introduction to computational geometry concepts from an Open University style course sequence.

Hebrew CG
קבוצה קמורה ופונקציה קמורה · YouTube

Hebrew support for convexity vocabulary around week 4.

Hebrew CG
גיאומטריה חישובית · Omrit Filtser

Hebrew course page describing geometric modelling with points, segments, polygons, and efficient algorithms.

AI Usage

Using an AI assistant is encouraged in this course for exploration, code review, data-cleaning ideas, map interpretation, and explanation practice. Two conditions keep the learning genuine: students keep full ownership of, and responsibility for, everything they submit, and must be able to explain and defend every GIS decision, geometric method, prompt-assisted result, and line of code.

Every weekly project increment follows a three-part model:

Part A · AI assistant welcomeExplore

Use an assistant to compare GIS workflows, generate small examples, clarify geometric predicates, or identify edge cases in spatial data.

Part B · verification requiredRun And Inspect

Run the workflow, inspect maps and attributes, check coordinate systems, test edge cases, and verify that generated outputs match the spatial question.

Part C · in plain languageReview And Defend

Explain the GIS meaning, the geometric representation, the algorithmic method, and where the result would fail or need better data.

Assessment And Grading

Grading is project-based, with weight on GIS understanding, correct spatial representation, algorithmic reasoning, map quality, validation, and the ability to defend decisions. The running project is the single deliverable, built up through weekly increments and graded at the three Student Project Presentations. There are no written exams.

ComponentWhat it coversWeight
Project · ProposalStudent Project Presentation 1: GIS problem, dataset, coordinate choices, geometric representation, planned algorithm, risks, and work plan (week 5).20%
Project · InterimStudent Project Presentation 2: working prototype or workflow, spatial data model, GIS outputs, algorithmic method, validation examples, and next steps (week 8).30%
Project · FinalStudent Project Presentation 3: complete GIS product or analysis, computational-geometry explanation, final maps or outputs, evaluation, limitations, and oral defense (week 13).50%

Bibliography

The reading list combines GIS foundations with computational-geometry and algorithmic-spatial-analysis references.

GIS Science
Geographic Information Systems and Science · Longley et al.

Fourth edition, 2015.

Intro GIS
Introduction to Geographic Information Systems · Kang-tsung Chang

Ninth edition, 2018 or 2019.

Fundamentals
GIS Fundamentals: A First Text on Geographic Information Systems · Paul Bolstad

Seventh edition, 2022.

Algorithms
Computational Geometry: Algorithms and Applications · de Berg, Cheong, van Kreveld, and Overmars

Core reference for geometric primitives, triangulations, arrangements, Voronoi diagrams, and geometric searching.

Algorithms
Computational Geometry in C · Joseph O'Rourke

Algorithmic reference for polygon operations, convex hulls, triangulation, and implementation-oriented geometry.

Principles
Principles of Geographical Information Systems · Burrough and McDonnell

Third edition, 2015.

ArcGIS Pro
Getting to Know ArcGIS Pro · Esri Press

Edition published in 2024.