Which technique helps maintain performance when rendering distant vegetation in a terrain?

• A. Render all vegetation with high detail.
• B. Use billboards for distant vegetation to reduce GPU load.
• C. Increase shadow distance for all vegetation.
• D. Disable occlusion culling.

Answer: (B)

When distant vegetation is rendered, the goal is to keep the scene visually convincing without overloading the GPU with geometry. The best approach is to swap far-away vegetation for billboards—flat 2D sprites that always face the camera. From a distance, the exact 3D shape isn’t noticeable, but the overall silhouette and density remain, so you still see a lush terrain. Because billboards use far fewer vertices and simpler shading, they dramatically reduce GPU work and fill rate, which keeps frame times lower as the number of distant plants increases. It's also common to pair billboards with distance-based LOD transitions so objects switch from full 3D to billboards smoothly as they move farther away. By focusing on cheaper representations for distant geometry, you maintain performance while preserving the expected look of the terrain.