This is our standard environment light, a production-ready geometric area light supporting a full feature set.
Specifies the exposure of the area light as a power of 2. Increasing the exposure by 1 will double the energy emitted by the light source. A value of 0 produces an intensity of 1 at the source.RIB: float exposureDefault: 0.0
Environment map to be used for Image-Based Lighting (IBL) using a High Dynamic Range image (HDR). The environment map will be importance-sampled to define a ray distribution respecting the intensity distribution in the image. If the image contains small hot spots (pixel values above 1.0, like 100+) you will get intense illumination with sharp shadows. If the hot spots are large, the shadows will look blurry.
If the image doesn't contain pixel values above 1.0 (Low Dynamic Range image or LDR), the illumination will look like colored ambient occlusion.RIB: string rman__EnvMapDefault: ""
Tint the environment color by this color.RIB: color envTintDefault: | 1.0 1.0 1.0 |
This switch will change the way the environment is computed:
- The resolution of the environment sphere is set by Procedural Resolution. It means, for example, that a 4096x2048 environment image will be re-sampled at 1024x512, if this is the selected Procedural Resolution value.
- The Procedural Color will be evaluated and then multiplied by the Environment Image (if defined). Shading Rate, Tint, Exposure, and Color Temperature will also be applied as usual.
- The resolution of the environment sphere will be defined by the Environment Image's resolution and the Shading Rate.
- Procedural Color is ignored.RIB: float enableProceduralDefault: 1
This is controlling the resolution of the environment.
If set to Automatic, the Environment Images' resolution will be used. If the Environment Image field is empty, a very low resolution will be used instead.RIB: float rman__ProceduralResolutionDefault: 1024 512
This parameter allows you to use a node-based input for the environment map. Use this as an alternative to an explicit map input. This allows you to use a file node and manipulate the colors at runtime.RIB: color proceduralColorDefault: | 1.0 1.0 1.0 |
No environment map and a white procedural color will give you the "Ambient Occlusion" look. Don't forget to set all surfaces to diffuse white and disable indirect illumination.
Turns color temperature on or off.RIB: float enableTemperatureDefault: 0
Unlike the basic light color, this allows the user to easily pick plausible light colors based on standard temperature measurements.
Defaults to 6500K, which should be very close to white on most monitors (D65 illuminant).RIB: float temperatureDefault: 6500
Scale the specular contribution of this light.RIB: color specAmountDefault: | 1.0 1.0 1.0 |
Scale the diffuse contribution of this light.RIB: color diffAmountDefault: | 1.0 1.0 1.0 |
Light sampling is automatic, but you may occasionally have to override the allocated sample budgets to clean up noise in direct lighting.
Fixed Sample Count
Override the automatic sample allocation and use a fixed number instead. Negative values disable this feature.RIB: float fixedSampleCountDefault: -1
Re-balance the automatic sample allocation. An importance of 2 will allocate twice the regular sample budget to this light.
This method is often preferable to Fixed Sample Count, as it only biases the automatic estimates.RIB: float importanceDefault: 1.0
Enable ray-traced shadows.RIB: float enableShadowsDefault: 1
The color of the shadows cast by emitted light.RIB: color shadowColorDefault: | 0 0 0 |
Adaptively sample the lights shadows.
Conservative mode will trace a larger percentage of the shadow rays, which will result in less acceleration, but potentially higher quality shadows.
Aggressive will trace fewer rays, which can result in more significant speedups.RIB: float adaptiveShadowsDefault: 1
Shadow Max Distance
Limits the shadow distance. Any value smaller or equal to 0.0 will be ignored and the shadow distance will be unlimited. Defaults to -1 : unlimited shadow distance. Can be used to optimize shadow rays in very large scenes but may introduce artefacts if set too short. Use a small value with a white environment light to achieve a short-range ambient-occlusion look.RIB: float shadowMaxDistDefault: -1
Shadow Trace Bias
Ray tracing bias for shadow computations. -1 uses the automatically computed bias value.RIB: float shadowTraceBiasDefault: -1
Set of geometry to consider for traced shadow intersection.RIB: string shadowSubsetDefault: ""
Don't Trace Subset
Set of geometry to ignore for traced shadow intersection.RIB: string shadowExcludeSubsetDefault: ""
Specify the group membership used for per-light AOVs.
Legacy. Keep at 1.RIB: float intensityDefault: 1.0