One of the major additions to the game engine was a full terrain editor with support for screen space reflections, allowing for realistic water and polished surfaces.

Terrain Editor Overview

The terrain editor provides artists with intuitive tools for:

  • **Height-based sculpting** of terrain using various brush shapes
  • **Material painting** with layered textures
  • **Water placement** with configurable properties
  • **Environmental object placement** for trees, rocks, and structures

Screen Space Reflections Integration

Screen space reflections (SSR) provide dynamic reflections using only the current frame's color buffer, without requiring expensive cubemap lookups.

How SSR Works

1. Sample the normal of the current pixel from the normal texture

2. Calculate reflection ray from view direction and surface normal

3. Trace ray through screen space, stepping until hitting occluded content

4. Sample color from the color buffer at the intersection point

5. Blend the reflected color with the base surface

Advantages

  • No preprocessing required (unlike cubemaps)
  • Dynamic reflections update every frame
  • Uses existing framebuffer data
  • Cheap compared to real-time cubemap generation

Limitations

  • Only reflects what's already rendered (can't reflect off-screen objects)
  • Limited to geometry within the screen bounds
  • May produce artifacts at screen edges

Implementation in the Terrain Editor

The editor allows terrain artists to:

  • **Toggle SSR** on specific terrain patches
  • **Configure reflection intensity** per surface
  • **Adjust roughness values** which affect reflection blur
  • **Preview in real-time** as they paint and sculpt

The SSR implementation integrates seamlessly with the existing deferred rendering pipeline, allowing multiple layers of reflective surfaces without significant performance overhead.

Results

The combination of a powerful terrain editor with SSR support enables:

  • **Realistic water surfaces** that reflect the surrounding environment
  • **Polished architectural surfaces** with dynamic reflections
  • **Quick iteration** for level designers without shader knowledge
  • **Performance-conscious** reflections that scale with hardware capabilities