Light

A light entity represents a light source in the environment.

• light_type: The type of light source
  • Ambient: An uniform light source.
  • Directional: A directional light source, lighting everything in front of it.
  • Point: A point light source.
  • Spot: A spot light source, akin to a focused light or a torchlight.
• light_flags:
  • Static: Whether the light is static. A static light can be further optimized. For example it could be baked in a lightmap or its shadow map can be precomputed instead of updated every frame.
  • Specular: Whether the light produces specular reflections.
  • CastShadows: Whether the light cast shadows.
  • SecondDepthShadows: Whether to use the back faces to update the shadow maps.
  • Cookie: Whether to use a projected texture.
  • CookieProbe: Used in with Cookie specifies that the projected texture is a light probe, aka that it contains some precomputed lighting information to be used by the light.

Color

• intensity (bound): The light intensity.
• diffuse (bound): The light's diffuse color component.
• specular (bound): The light's specular color component, this is the color used to similuate the light's reflections.

Attenuation

• mode: Indicates the type of attenuation, the attenuation is the light's intensity falloff over distance.
  • None: the intensity is constant all over the light's influence area.
  • Linear: the intensity of the lights falloff linearly to reach 0/no intensity at the light's far_end distance.
  • Bicubic: the intensity of the lights falloff following a bicubic curve to reach 0/no intensity at the light's far_end distance.
  • Complex: a more complex fallback setup by near_start, near_end, far_start, far_end, this is similar to 3DSMax's standard light's setup.
• cosine_bias: The cosine bias indicates how much back faces are lit, at zero backfaces are not lit at all, as it reach one back faces are lit in the same way as front faces. Note by not lit what is really meant is "take the shadow_color".

Shadow

• shadow_color (bound): Specifies the color used for back faces and shadowed areas.
• filter: The type of shadow filter when the light cast shadows.
  • LowQuality: The cheapest filter available, produces a blocky, usually single sample, low quality filter.
  • MediumQuality: A decent compromise between speed and quality, produces a decently smoother shadow border, usually using 4 shadow samples.
  • HighQUality: The "best quality" filter available, usually at least 16 shadow samples, note that it procudes a much sharper shadow edge on most platform.
• cookie: Name of the projected texture associate with the light, this can be a 2d texture for spot lights, or a cross cubemap if using a CookieProbe.
• size: Resolution of the shadow map.
• bias: The shadow map bias factor.
• near_plane_distance: The near clipping plane distance used to build the shadow map.