GeoFusion, Inc.

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GeoFusion, Inc.

• Digital Earth Visualization
• Paul Hansen
• hansen_at_geofusion.com
• Chuck Stein
• stein_at_geofusion.com

www.geofusion.com
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GeoFusion, Inc.

• Santa Cruz based software technology company
• Based on Paul Hansens work with digital earth
  rendering
• Goals
• Create core technology for the GeoWeb
• Put an interactive digital earth on everyones
  desktop
• License software GeoMatrix Toolkit (SDK)
• Custom application development
• Rendering services

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Accelerating Digital Earth Development

• Early choice application vs. toolkit
• Digital Earth Application Programmers Interface
  (API) allows for a multitude of applications and
  uses
• Promote data sharing with non-proprietary
  projection and data format
• Provide customers the ability to use the Earth
  as an interface to desired functionality
• Platform independence

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GeoMatrix Digital Earth System

• The GeoMatrix Toolkit
• An Application Programmers Interface (API) for
  building digital Earth applications
• Uses a unique projection and global tessellation
  system that facilitates tile generation, texture
  mapping, rendering
• Tile generation and data format that supports
• Multi-resolution representation of source data
• Fast look-up database speeds demand paging of
  data tiles
• Valid/invalid (transparent) pixel determination
• Compression and format options

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GeoMatrix Digital Earth System

• Renders vast amounts of data
• Fast inclusion of data at run-time
• Real-time scene generation
• Continuous level-of-detail while zooming
• Platform independent, OpenGL based graphics
• Low cost hardware, highly optimized software
• Small libraries (DLLs 50-200k)
• API allows for rapid development of applications

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Requirements

• 128 Mb RAM
• 3D accelerated graphics
• OpenGL

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Native Data Types

• Multi-resolution, tiled representation of
• Imagery
• Terrain
• Vector
• Annotation

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GeoMatrix Toolkit Features

• Fully interactive, high performance 3D digital
  Earth platform
• Visualization of image, terrain, vector,
  annotation data
• Continuous level-of-detail while zooming
• Manages a vast number of datasets simultaneously
  attach and detach at will
• Platform independent C, object oriented API

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GeoMatrix Toolkit Features (cont.)

• Draw your own content into the GeoFusion rendered
  world
• Text, lines, 3D models, etc.
• Demand paging of local or remote data tiles
• Blend between image data layers
• Animate events over time
• Output arbitrary resolution images or frames for
  movies

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GeoMatrix Toolkit Modules
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GeoMatrix Applications
scene 1
scene 2
Multiple scenes/viewports
globe 1
globe 2
Coincident, concentric or offset
dataset 1
dataset 2
dataset 3
Image, Terrain, Vector, Annotation
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1km NASA Modus
1km pseudo-color bathymetry terrain
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6 inch aerial imagery draped over LIDAR elevation
data.
70 cm aerial imagery
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CIA map blended with satellite imagery over
terrain.
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Yosemite, California 8m black white DOQ
imagery on 10m DEM
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1km global bathymetry and terrain
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Example application of satellite models drawn on
top of GeoFusion rendered Earth.
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ESRIs ArcGlobe

• Available in ArcGIS 3D Analyst extension
• Tremendous increase in performance
• Interactive, supports layers, 3D models, etc.
• GIS is moving from flatland to the globe
• Allows viewing most data in ESRI geodatabase
• Prepares data on-the-fly, then caches tiles

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GeoMatrix core concepts

• 1. Tiled, multi-resolution data packaging. Tiles
  have a consistent size with a definite
  upper-bound, allowing them to be easily moved
  around and assembled into a view.
• 2. Unique tiling system (GeoMatrix) for the Earth
  globe. Hybrid system--combination of geographic
  projection and square polar projection. Smooth
  transitions across domain boundaries. Efficient
  treatment of polar singularities.

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GeoMatrix core concepts (cont.)

• 3. Fast recursive subdivision and fast,
  aggressive culling of "geometry (surface parts)
  outside the viewing window.
• 4. Fast and fine-grained level-of-detail (LOD)
  calculation allows the minimal collection of
  needed tiles to be accessed.
• 5. Introduction of higher-resolution data before
  it is easily visible. "New data appears
  "between" previously seen data rather than
  replacing it, and, for terrain data, gradually
  morphs to its full extent.

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GeoMatrix core concepts (cont.)

• 6. Fast data coordination and rendering allow a
  realistic Earth to be a 3D canvas for other kinds
  of data visualization. The GeoMatrix provides a
  spherical coordinate space infrastructure.
• 7. Creation of a set of software modules that
  make this technology available to a wide variety
  of applications developers through a set of
  innovative programming interfaces (APIs). The
  GeoMatrix Toolkit.

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Globe Faces
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Polar Projection
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Globe Mapping
top view
full globe
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Polar/Equatorial Congruency
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Mapping Function
90oN
0.0
P
P
1.0
45oN
180oW
90oW
135oW
-1.0
0.0
1.0
PX PX PY PY PY
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Coordinate Spaces

• Face coordinatesnormalized Cartesian
  coordinates per-face.
• Tile coordinatesquad-tree indexing F,L,R,C
• globe face index
• recursion level number
• row index
• column index

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Coded Vertexes

• Peano coding for vertex locations. Except
• no interleaved bits
• LSB is dedicated 1.0 bit
• location is within a particular tile
• Fast conversion between face coordinates.
• Combine vertex coding with tile coordinates.