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Multiple Representations with Overrides, Multiple Representations with Overrides, and their relationship toand their relationship to

DLM/DCM GeneralizationDLM/DCM Generalization

Paul HardyPaul HardyDan LeeDan Lee

phardy@esri.comphardy@esri.comdlee@esri.comdlee@esri.com

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ContextContext

•• This is a forwardThis is a forward--looking presentation, looking presentation, and much of the capabilities it describes and much of the capabilities it describes are still under development.are still under development.

•• As such, it is intended to give guidance As such, it is intended to give guidance as to likely future direction and should as to likely future direction and should not be interpreted as a commitment by not be interpreted as a commitment by ESRI to provide precise capabilities in ESRI to provide precise capabilities in specific releases.specific releases.

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Representations and Representations and OverridesOverrides

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Five Stages of Symbolization ControlFive Stages of Symbolization ControlStage 1 -Linear Features

(Tracks)

5 - FreeRepresentation

Stage 2 -GIS Dash symbol

Bad joinsand bends

4 - ManualOverride

3 - AutomaticRepresentation

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Solution ConceptsSolution Concepts•• One environment through GIS to finishingOne environment through GIS to finishing•• Cartographic RepresentationsCartographic Representations

–– HighHigh--quality rules for visualizationquality rules for visualization•• Stored in the databaseStored in the database

•• OverridesOverrides–– Exceptions to the rulesExceptions to the rules

•• Human knows better than machineHuman knows better than machine•• Can sometimes automate (culCan sometimes automate (cul--dede--sac roads)sac roads)•• Stored in the databaseStored in the database

•• Representation editing toolsRepresentation editing tools–– Intuitive, similar to IllustratorIntuitive, similar to Illustrator

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Screen or Print

Shape

GIS Feature

Symbol

Representation PipelineRepresentation Pipeline

Geometric Effect

Basic Symbol

RepresentationRule ID

Overrides(if any)

Rule Geometric Effect

Geometric Effect

Basic Symbol

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DemonstrationDemonstration

Representations & OverridesRepresentations & Overrides

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CulCul--dede--sac Processingsac Processing

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Free Representation Free Representation --editing of dashes for clarityediting of dashes for clarity

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Cartographic EditingCartographic Editing

•• See [Eicher & Briat 2005] ICA paperSee [Eicher & Briat 2005] ICA paper–– ““Supporting Interactive, Manual Editing of Supporting Interactive, Manual Editing of

Cartographic Representations in GIS Cartographic Representations in GIS SoftwareSoftware””

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Road crossingsRoad crossings

Road intersections ambiguousRoad intersections ambiguous

Use crossing areas as maskUse crossing areas as maskAutomatically calculate crossingsAutomatically calculate crossings

Can add parapets automaticallyCan add parapets automatically

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Escarpment Escarpment –– Stages of ControlStages of Control

2GIS symbol

3Representation

4Manual Override

1Line features

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Swiss topographic map Swiss topographic map representationrepresentation

Data copyrightswisstopo

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DatabaseDatabase--centered Workflowscentered Workflows

ViewsViews

AnalysisAnalysis

Mission CriticalMission CriticalApplicationsApplications

UpdatesUpdatesMapsMaps

EnterpriseEnterpriseGeodatabaseGeodatabase

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Simple case Simple case –– existing featuresexisting features

CartographicRepresentation(Clearer roads)

Town Plan Map

Feature Class

(Roads)

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CartographicRepresentation(Clearer roads)

Feature Class

(Roads)

Multiple RepresentationsMultiple Representations

Town Plan map

AnotherRepresentation(Special roads)

Leisure map

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Enterprise (DLM) CaseEnterprise (DLM) Case

DLMFeature Class

(Detailed Roads)

CartographicRepresentation(Better roads)

Town Plan map

AnotherRepresentation(Special roads)

Leisure map

Feature Class

(Roads)

Extract via Geoprocessing:•Copy•Select Subset•Generalize

Cartographic Database

Landscape Database

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Landscape Models, Cartographic Models, and ProductsLandscape Models, Cartographic Models, and Products

1:200K Atlas

1:50K Topo

1:100K Topo

1:250K Sheet

1:10K Sheet

1:10K PDF

VisualProduct

Cartographic Model

DCM_Small

DCM_Mid

DeriveFeatures

DeriveFeatures

DCM_Basic

Cartographic Generalization

DeriveFeatures

DLM Fine(Master)

Change in Real World

Landscape Model

Fine Routing

DLMMedium

DeriveFeatures

Model Generalization

DLMCoarse

DeriveFeatures

Course Routing

DataProduct

Derive Reps

Derive Reps

Rep250SRep200A

Rep100TRep50T

Derive Reps

Rep10SRep10P

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Geoprocessing and GeneralizationGeoprocessing and Generalization

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GeoprocessingGeoprocessingCore tools

Python Scripts and AMLs

Models (including other tools)

ArcToolbox

Any executable

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GeneralizationGeneralization•• Generalization is about abstractionGeneralization is about abstraction

–– exaggerate the importantexaggerate the important–– subdue or remove irrelevant detailsubdue or remove irrelevant detail–– move reality to make spacemove reality to make space

•• Needs pattern recognitionNeeds pattern recognition–– Humans find hard, while computers find harder!Humans find hard, while computers find harder!

1:10,000 1:50,000 1:250,000

Crow

n Copyright, C

ourtesy OSG

B

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Aggregate polygons

Aggregate buildings avoiding streetsSimplify buildings Displace buildings

from roads

Collapse double-line roads to centerlines Displace linear features

Generalization AlgorithmsGeneralization Algorithms

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Generalization Process ModelsGeneralization Process Models

Data Ordnance Survey GBCrown Copyright

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New Generalization ToolsNew Generalization Tools• Four New tools to Generalize Database Features

– Simplify Polygon - Simplifies a polygon by removing small fluctuations or extraneous bends from its boundary and preserves its essential shape

– Simplify Building - Simplifies the boundary or footprint of a building polygon while maintaining its essential shape and size

– Aggregate Polygon - Combines disjoint and adjacent polygons into new area features based on a distance

– Collapse Dual Lines to Centerlines - Derives centerlines (single lines) from dual-line features

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Simplify PolygonsSimplify Polygons

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Simplify BuildingsSimplify Buildings

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Aggregate PolygonsAggregate Polygons

Non-orthogonal

Orthogonal

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Collapse DualCollapse Dual--Lines To CenterlineLines To Centerline

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Generalization is HardGeneralization is Hard•• CanCan’’t do it a feature at a timet do it a feature at a time

–– Involves relationships with neighboursInvolves relationships with neighbours•• CanCan’’t do it a layer at a timet do it a layer at a time

–– Relationships are with features of many classesRelationships are with features of many classes•• CanCan’’t do uniformlyt do uniformly

–– Even features of one class have different surroundingsEven features of one class have different surroundings•• CanCan’’t do it across whole map at oncet do it across whole map at once

–– Must localize or partitionMust localize or partition•• CanCan’’t do it just on geometryt do it just on geometry

–– Needs understanding of topology and of attributesNeeds understanding of topology and of attributes

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Possible Generalization FlowPossible Generalization Flow

Data Structure

Enrichment

Meso area Classification

Context Analysis

Dispatch to Appropriate Algorithm

PartitioningPattern &

Group Detection

Reclassify, Aggregate Exaggerate, Simplify, Displace, Typify, …

Loop until Done

Check

If worse, undo

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UpdateUpdate

•• Change at largest scale then propagate Change at largest scale then propagate incremental differencesincremental differences

•• See [Briat, Monnot, Kressmann 2005] See [Briat, Monnot, Kressmann 2005] ICA paper:ICA paper:–– ““Incremental Update of Cartographic Data Incremental Update of Cartographic Data

in a Versioned Environmentin a Versioned Environment””

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SummarySummary

•• Advanced cartographic representation mechanisms Advanced cartographic representation mechanisms and cartographic editing tools will soon become and cartographic editing tools will soon become available in a commodity GIS. available in a commodity GIS.

•• Together with production automation and graphics Together with production automation and graphics capabilities they will dramatically change the scope of capabilities they will dramatically change the scope of automated cartography, facilitating the generation of automated cartography, facilitating the generation of multiple products from a central database. multiple products from a central database.

•• The human freedom enabled by the override system, The human freedom enabled by the override system, combined with the symbolization rule pipeline, will combined with the symbolization rule pipeline, will permit highpermit high--quality attractive cartography within a quality attractive cartography within a databasedatabase--centered environment.centered environment.

•• The representation and override mechanisms, together The representation and override mechanisms, together with the geoprocessing framework also form the with the geoprocessing framework also form the foundation for generalization processes and foundation for generalization processes and incremental update propagationincremental update propagation

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Questions and Comments?Questions and Comments?

phardy@esri.comphardy@esri.com