This plugin provides a basic volumetric path tracer that can be used to compute approximate solutions of the radiative transfer equation. This particular integrator is named “simple” because it does not make use of multiple importance sampling. This results in a potentially faster execution time.
On the other hand, it also means that this plugin will likely not perform well when given a scene that contains highly glossy materials. In this case, please use volpath or one of the bidirectional techniques.
This integrator has special support for index-matched transmission events (i.e. surface scattering events that do not change the direction of light). As a consequence, participating media enclosed by a stencil shape (see Section 8.1 for details) are rendered considerablymore efficiently when this shape has no 16 BSDF assigned to it (as compared to, say, a dielectric or roughdielectric BSDF).
• This integrator performs poorly when rendering participatingmedia that have a different index of refraction compared to the surrounding medium.
• This integrator has difficulties rendering scenes that contain relatively glossy materials (volpath is preferable in this case).
• This integrator has poor convergence properties when rendering caustics and similar effects. In this case, bdpt or one of the photon mappers may be preferable.
16 this is what signals to Mitsuba that the boundary is index-matched and does not interact with light in any way. Alternatively,
the mask and thindielectric BSDF can be used to specify index-matched boundaries that involve some
amount of interaction.
- Max. path depth : integer
- Specifies the longest path depth in the generated output image (where -1 corresponds to ∞). A value of 1 will only render directly visible light sources. 2 will lead to singlebounce (direct-only) illumination, and so on. (Default: -1 -> 24 @ blender)
- Russian roulette starting depth : integer
- Specifies the minimum path depth, after which the implementation will start to use the “russian roulette” path termination criterion. (Default: 5 -> 10 @ blender)
- Strict Normals : boolean
- Be strict about potential inconsistencies involving shading normals? See page 154 for details. (Default: no, i.e. false)
- Hide Emitters : boolean
- Hide directly visible emitters? See page 149 for details. (Default: no, i.e. false)