3D Game Programming All in One

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3D Game Programming All in One

• By Kenneth C. Finney

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Chapter 12Terrains

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Terrains

• For outdoor game environments
• Terrain is a topography model combined with
  ground cover textures

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Terrains

• Terrains Explained
• Tiles are the basic terrain unit
• Terrain tiles are a collection of polygons, like
  any other 3D model

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Terrains

• Terrains Explained
• Fidelity accuracy of terrain
• Spread uniqueness of terrain areas, related to
  tile repetition
• Freedom ability of player characters to move
  within the terrain

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Terrains

• Terrains Explained
• Terrain Data can be obtained from
• U.S. Geological Survey
• Formats
• Digital Elevation Model (DEM)
• Digital Terrain Model (DTM)
• Spatial Data Transfer Standard (SDTS)

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Terrains

• Terrain Modeling
• External modeling method terrain as another
  object in the game world
• Internal method game engine contains specialized
  terrain rendering code

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Terrains

• Height Maps
• Grayscale images (8 bits per pixel) that
  represent terrain
• Similar to topographical maps
• Resolution is an issue (leads to either small
  tiles, or poor fidelity)

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Terrains

• Terrain Cover
• Textures used to represent soil types, flora,
  debris, and litter
• Grass, Flowers, Dirt, Pebbles
• Rocks, Trash, Litter, Pavement
• Concrete, Moss, Sand, Stone

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Terrains

• Tiling
• Issues similar to those found in structure
  textures
• seamless transitions
• appropriate lighting

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Terrains

• Lab 1 Terrain
• Use paint program to create height map from a
  contour map
• Mathematically determine required image sizes
• Use the Terraform Editor to add height map game
  world

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Terrains

• Applying Terrain Cover
• Cover textures look best when created for tiling
• Use grid textures to assist with sizing and sight
  lines
• Paint terrain using the built-in Torque Terrain
  Texture Painter

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Terrains

• Lab 2 Terrain Cover
• Use images to create terrain cover
• Use the Terrain Texture Painter to apply terrain
  cover
• Add terrain cover (materials) to available
  selection
• Use guide images to apply cover

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Summary

• Terrain topography cover
• Terrain characteristics fidelity, spread,
  freedom
• Source data USGS (real world), maps, onsite
  measurement
• Height-maps are like topographical maps
• Adjust height-maps to match game world size