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Electronic Topographic Map Design

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Electronic Topographic Map Design Powered By Docstoc
					                Performance of Map Symbol and
                Label Design with Format
                and Display Resolution Options
                Through Scale for The National Map

                Follow-up on AutoCarto 2011 talk


    Cynthia A. Brewer, Pennsylvania State University

    Penn State Research Assistants:
    Paulo Raposo, Chelsea Hanchett, Andrew Stauffer



C. Brewer, NationalMapping.us                         CEGIS, June 2011
             Multiscale topographic map design

• Draft design for mapping from The National Map data
• Suited to multiple resolutions
    – Onscreen 91 ppi (desktop)
    – 120 ppi (laptop)
    – Print 400 ppi
• Suited to multiple formats
    –   PDF
    –   ArcMap
    –   Cached tile (web)
    –   Print
• Supports hydrographic generalization evaluation

C. Brewer, NationalMapping.us              CEGIS, June 2011
                     Quality rating categories

A - Label appearance and readability
B - Label positioning and generalization
C - Point symbol appearance
D - Point generalization
E - Line symbol appearance
F - Line generalization
G - Area symbol appearance
H - Area generalization
I - Terrain appearance
J - Terrain generalization
K - Vertical integration between layers
L - Overall appearance of map (Goldilocks)


C. Brewer, NationalMapping.us                CEGIS, June 2011
                     Quality rating categories

E - Line symbol appearance
    – Line appearance too similar to other line symbols
    – Line too wide (or too narrow)
    – Line form is jagged (due to rendering)
    – Poor pattern choice (e.g., dash)
    – Poor multilayer pattern combination (e.g., dash, centerline, line
      casing)
    – Poor color(s)
    – Interference from other features above or below line
    – Poor symbol-level drawing (line should be above or below
      another feature type)



C. Brewer, NationalMapping.us                           CEGIS, June 2011
WV
1:24K




C. Brewer, NationalMapping.us   CEGIS, June 2011
WV
1:50K




C. Brewer, NationalMapping.us   CEGIS, June 2011
WV
1:100K




C. Brewer, NationalMapping.us   CEGIS, June 2011
WV
1:250K




C. Brewer, NationalMapping.us   CEGIS, June 2011
WV
1:500K




C. Brewer, NationalMapping.us   CEGIS, June 2011
WV
1:1M




C. Brewer, NationalMapping.us   CEGIS, June 2011
                  Example ratings aggregation




C. Brewer, NationalMapping.us             CEGIS, June 2011
                          Experiment design

5-inch map patches examined:
• by 3 raters
• at 6 scales
• for 8 subbasins
• at 2 resolutions
• in 2 file formats

• 3 x 6 x 8 x 2 x 2 = 576 evaluated (June 2011)




C. Brewer, NationalMapping.us                 CEGIS, June 2011
                      Quality ratings – results
                     Comments on problems:    #     %
A - Label appearance and readability         398    15
                                                              Labels 28%
B - Label positioning and generalization     335    13
C - Point symbol appearance                  270    10
D - Point generalization                      74     3
E - Line symbol appearance                   436    17
                                                              Lines 26%
F - Line generalization                      251    10
G - Area symbol appearance                   179     7
H - Area generalization                      124     5
I - Terrain appearance                       121     5      Labels and lines
                                                            together 54%
J - Terrain generalization                   111     4
                                                            of issues
K - Vertical integration between layers      146     6
L - Overall appearance of map                182     7
                          Total comments:    2627
C. Brewer, NationalMapping.us                            CEGIS, June 2011
                      Quality ratings – results
                                            %
E - Line symbol appearance                  17 = 10 Arc + 6 PDF
A - Label appearance and readability        15 = 10 Arc + 6 PDF
B - Label positioning and generalization    13 = 7 Arc + 6 PDF
C - Point symbol appearance                 10
F - Line generalization                     10
G - Area symbol appearance                   7    Overall, 1.4x
L - Overall appearance of map                7    as many
K - Vertical integration between layers      6    problems in
                                                  ArcMap views
H - Area generalization                      5
                                                  than PDF
I - Terrain appearance                       5
J - Terrain generalization                   4
D - Point generalization                     2


C. Brewer, NationalMapping.us                   CEGIS, June 2011
                       Quality ratings – results

• Largest differences between Arc and PDF ratings in
  “appearance” categories:
         Category                Arc Comments   PDF Comments
         Label appearance        240            158
         Line appearance         273            163
         Point appearance        170            100
         Terrain appearance      86             35

• Less difference on more data-driven issues:
        Category                 Arc Comments   PDF Comments
        Vertical integration     75             71
        Terrain generalization   61             50


C. Brewer, NationalMapping.us                          CEGIS, June 2011
                      Quality ratings – results

• Most issues at middle scales:
                     Scale        % share of all comments
                      24K                   14
                      50K                   16
                      100K                  19
                      250K                  18
                      500K                  18
                      1M                    15




C. Brewer, NationalMapping.us                     CEGIS, June 2011
                      Quality ratings – results

• About 1/3 comments (34%) seeking to refine
  generalization

• Small difference in generalization comments counts
  between Arc and PDF formats (53 / 47% split)




C. Brewer, NationalMapping.us                 CEGIS, June 2011
                   Format Makes a Difference



                                                    MO
                                                  250K
                                               enlarged



    ArcMap
     120 ppi


                        PDF
                      120 ppi

C. Brewer, NationalMapping.us            CEGIS, June 2011
                                  Resolution
                                   Makes a
                                  Difference


                                             MO
                                           250K
ArcMap
                                        enlarged
  91 ppi


      ArcMap
       120 ppi


                          PDF
                        120 ppi

  C. Brewer, NationalMapping.us   CEGIS, June 2011
                        Example comments:
            Line symbol appearance, area generalization


E/CO/100: line too narrow (flowlines); interference from other
features above or below line (flowline, reservation, roads)
E/UT/50: highway casings deteriorating due to pixelation; railway
ticks not rendered evenly across line; intermittent stream dashes
seem inconsistent due to rendering; river has jagged edge

H/FL/500: areas too small to suit scale (waterbodies); too many
area features (waterbodies); area shapes too complex
(waterbodies)
H/UT/500: Too many area features (reserve); Area shapes too
complex (area hydro and incorp place); Areas too small to suit
scale (NA reservation)
C. Brewer, NationalMapping.us                      CEGIS, June 2011
CO
1:100K




C. Brewer, NationalMapping.us   CEGIS, June 2011
UT
1:50K




C. Brewer, NationalMapping.us   CEGIS, June 2011
                 Example comments on Labels
         appearance/readability, positioning/generalization


A/TX/250: Individual characters unaligned (e.g., county borders);
letter forms jagged
A/STL/24: Different case would better suit feature (change to lower
case)(EMS); Too large (ctr); Poor styling (EMS spacing too wide)

B/ATL/50: some labels conflating with vector symbols underneath;
some local road labels following roads too closely
B/STL/50: Too many features of one type are labeled (schools);
Difficult to understand location of named feature (EMS); Hierarchy
of labels would better suit feature type (pop and incorp place)



C. Brewer, NationalMapping.us                      CEGIS, June 2011
TX
1:250K




C. Brewer, NationalMapping.us   CEGIS, June 2011
 ATL
 1:50K




C. Brewer, NationalMapping.us   CEGIS, June 2011
STL
1:50K




C. Brewer, NationalMapping.us   CEGIS, June 2011
                   Summary of Quality ratings

• Large majority of problems with rendering lines and
  labels, some of generalization of lines

• More issues in Arc than PDF

• Most issues noted at 100K, 250K and 500K

• Worst concentrations of issues in dense urban areas




C. Brewer, NationalMapping.us                CEGIS, June 2011
            Summary of Quality ratings - details

• Patterned and cased lines getting pixelated
• Hydro needing simplification at smaller scales
• Road labels often follow too closely, hydro labels too far
• Labels should have greater hierarchy and consistent use
  of case
• Some local roads need elimination at 100K
• Cluttering of labels at 100K in urban areas, sometimes
  hard to see association to features
• Some conflation between letter forms and linear symbols
  below them


C. Brewer, NationalMapping.us                 CEGIS, June 2011
            Summary of Quality ratings - details

• Highway numbers overrunning shields/ovals, or not
  centered in them
• Vertical integration issues between hydro and admin
  areas (e.g., county borders)
• Intermittent streams too fine, hard to see
• Index contours hard to distinguish; contours not labeled
  often enough in general
• Too many points on map at 100K
• Hillshades sometime appear pixelated and grainy;
  require simplification other times


C. Brewer, NationalMapping.us                 CEGIS, June 2011
                                What’s Next

• Refine design
• Refine hydro LoD 50K~200K
  (e.g., braiding, centerlines, islands)
• More hydro LoDs for 200K to 1M
• Generalize additional layers
• More categories of importance for pruning through
  scale (e.g., airports, populated places, local roads)
• Evaluate Preview of appearance for cached web display
• Attend to vertical data integration



C. Brewer, NationalMapping.us                 CEGIS, June 2011
                      Acknowledgements

Funding:
USGS Center of Excellence for Geospatial Information Science
  (CEGIS), 2007 to present funding

              Thanks to:
              babs buttenfield, CU Boulder
              Larry Stanislawski, Lynn Usery, Tom Hale, USGS-CEGIS
              Charlie Frye, ESRI

                         Penn State Research Assistants:
                         Paulo Raposo
                         Chelsea Hanchett
                         Andrew Stauffer

C. Brewer, NationalMapping.us                         CEGIS, June 2011

				
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posted:12/9/2011
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