Deterministic Calculation Properties without Photon Map
This page describes the parameters to set when wanting to create a deterministic inverse simulation without generating a photon map.
The deterministic algorithm allows you to perform determinist simulations. This type of simulation produces results showing little to no noise but that are considered as biased.
The deterministic simulation is entirely appropriate to analyze and render simple optical paths with unidirectional contributions.
When contributions and optical interactions are multiple, it is recommended to use Monte Carlo algorithm or generate a photon map.
Algorithm
_Simulation_Settings_Inverse_03.png)
Example of simulation without photon map
Propagation Properties
_Simulation_Settings_Inverse_07.png)
Use Rendering Properties as Optical Properties
Activating this option allows you to automatically convert appearance properties into physical parameters according to the following conversion table.
|
Appearance Parameters |
Physical Parameters PP(l) |
|
Intensity + Color[RGB] |
Lambertian L(l) |
|
Ambient + Color[RGB] |
Lambertian L(l) |
|
Shine |
Gaussian Angle a |
|
Highlight + Highlight[RGB] |
Gaussian Reflection |
|
Reflection |
Specular reflection SR(l) |
|
Transparency + Highlight[RGB] |
Specular transmission ST(l) |
Ambient Sampling
This parameter defines the sampling. The sampling corresponds to the quality of the ambient source. The greater the value, the better the quality of the result, but the longer the simulation. The following table gives some ideas of the balance between quality and time.
|
Ambient Sampling = 20 Reference Time / 3 |
_Example_Ambient_Sampling_20RefTime3_01.png) |
_Example_Ambient_Sampling_20RefTime3_02.png) |
|
Default value Ambient Sampling = 100 Reference Time |
_Example_Ambient_Sampling_100RefTime_01.png) |
_Example_Ambient_Sampling_100RefTime_02.png) |
|
Ambient Sampling = 500 Reference Time x 4 |
_Example_Ambient_Sampling_500RefTime4_01.png) |
_Example_Ambient_Sampling_500RefTime4_02.png) |
Maximum Number of Surface Interactions
This number defines the maximum number of impacts a ray can make during propagation. Once the ray has interacted N times with a surface, it is stopped.
Anti-Aliasing
The anti-aliasing option allows you to reduce artifacts such as jagged profiles and helps refine details. However, this option tends to increase simulation time.
_Antialiasing_Deactivated.png) |
_Antialiasing_Activated.png) |
|
Anti-aliasing deactivated Reference Time / 2 |
Default Value Anti-aliasing activated Reference Time |
Specular Approximation Angle
The specular approximation angle option allows you to replace the specular reflection by a gaussian reflection to increase the probability of the propagated rays to reach the sources.
This option also allows you to decrease the noise in the simulation's results and improve simulation time.
The typical application is the rendering of automotive tail lamps lit appearance. For this application, a typical value would be 5 to 10 degrees.