Vegetation

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Plants/Vegetation is a common type of prop asset used in environment art, set dressing and level design.

Types of Vegetation

In nature plants evolved to grow in different forms to fill gaps (niche) in their local environment (habitat). In a forest for example a vine grows up a tree to reach light that is less available on the ground.

Vegetation Types:

  • Canopy (Largest trees)
  • Mid story (Small trees, large shrubs)
  • Understory (shrubs)
  • Ground cover (Vines, grasses, herbs)

See Stratification

Biomes

Some general Biome/habitat types include:

  • Forest
  • Rainforest/Jungle
  • Grassland
  • Wetland/Swamp
  • Alpine
  • Desert

There are countless types of habitats which are determined by biogeographic factors.

Modelling Techniques

Missing textures showing foliage billboards in csgo on cs_insertion

Env Artists use a combination of geometry and textured 2d planes to hopefully create a believable presentation of a the plant they are aiming to create.

Geometry / Mesh
Comprises the thick section of a plant such as the trunk and large branches.
Alpha Cards
Double sided non-closed textured mesh with alpha mask (Large, curved and/or undulating leaf margins, ie. Aroids).
Billboards / Imposter Cards
A double sided 2D textured plane with alpha mask (similar to Sprite Cards in Particles). Planes can be fixed to the world or face towards the camera (with particle system). Fixed planes are incrementally rotated (2 = 90°, 4 = 45°, etc.) around Z Axis. (Grass, herbs).
Warning.pngRisk of Confusion: The term billboard technically refers to the camera facing vertical planes but can be interchangeable with alpha cards, ie. Billboard Clouds.
Billboard Clouds
A non symmetrical technique of "billboarding" that maximizes viewable angles while aiming to minimize the amount of billboards (Leaf clumps, bushes).
Shell Texturing
A technique of layering billboards above one another to create the appearance of noisy repetitive 3d geometry (such as short grass) over large areas.

Textures

  • alpha testing

Materials

Animation

LODs

Common Issues

Performance

  • Overdraw

Lighting

Resources

At the end of the video they recommend Tree_It Tree_It (free version on dev website) & Plant Factory Note.pngNote: Website in firefox is bugged