Describes a renderer's sorting layer range.
ScriptableRenderContext.DrawRenderers, FilterRenderersSettings.sortingLayerRange.
| all | A range that includes all objects. | 
| lowerBound | Inclusive lower bound for the range. | 
| upperBound | Inclusive upper bound for the range. | 
| SortingLayerRange | Sets the inclusive range for a sorting layer object. |