The Info channel kernel evaluates scene data and renders the data as color images that can be used in post processes for compositing. Figure 1 shows the Info channel settings in the OctaneRender settings tab.
Figure 1: The Info Channel settings in the OctaneRender settings.
Info Channel Kernel Parameters
Sets the maximum number of samples per pixel before the rendering process stops. The higher the number of samples per pixel, the cleaner the render. There is no rule as to how many samples per pixel are required for a good render, it is subjective and may vary depending on the content and complexity of the scene being rendered.
Sets the filter size in terms of pixels. This can improve aliasing artifacts in the render. However, if the filter is set too high, the image can become blurry.
Is the distance between the geometry and the light ray when calculating ray intersections for lighting and shadowing. Larger values push rays away from the geometry surface. Lower values are more accurate, but can cause artifacts on large or distant objects. Ray Epsilon is similar to raytracing bias in other rendering engines. Adjust Ray Epsilon to reduce artifacts in large scale scenes.
This option removes background images or colors created by the SunSky environment node from the rendered image while not affecting any lighting cast by the environment. This can be useful if the user wants to composite the render over another image and does not want the background to be present. Note that objects appearing in the RGB channels will have a bleeding edge which may appear as noise artifacts however these edges are not included in the alpha channel itself.
Alllows any object with transparency (specular materials, materials with opacity settings and alpha channels) to cast a shadow accordingly instead of behaving as a solid object.
Info Channel Type
This parameter specifies the various passes that can be rendered and used in the compositing process.
- Geometric normals: the vectors perpendicular to the triangle faces of the mesh.
- Shading normals: the interpolated normals used for shading. This does not take into account the bump map of the object. The result is less faceted and smoother than Geometric normals.
- Position: A color coded image that shows the position of the objects in the scene, often used in compositing to help position 3D rendered images from different renders..
- Z-depth: An image shaded based on the distance between the objects in the scene and the position of the rendering camera.
- Material ID: Every material assigned in the scene is represented as a separate color.
- Object Layer ID: A color coded image, each object is colored based on their Object Layer Id settings. The Layer ID setting is found in the Octane Attributes section in the object’s shape node tab.
- Texture Coordinates: A color coded image showing a gradient map based on the direction of the object’s UV texture coordinates.
- Wireframe : Shows the mesh as represented by triangles outlined in black lines.
- Ambient Occlusion (AO): A render shaded using ambient occlusion calculations. Recessed areas of the surfaces are shaded darker than their surroundings.
- Interpolated Vertex Normal: A color coded image shaded based on the direction of the object’s vertex normals.
- Render Layer ID: A color coded image, each object is colored based on their Object Layer Id settings. The Layer ID setting is found in the Octane Attributes section in the object’s shape node tab. Render layers are covered in more detail in the Render Layers section of this guide.
- Render Layer Mask: A mask rendered based on an object’s Layer ID and render layer membership. Render layers are covered in more detail in the Render Layers section of this guide.
- Environment: Renders just the background image as set by the Sun Sky node
Determines the maximum depth as shown in the shading of the Z-depth info channel pass.
Sets the maximum value that can be shown for the texture coordinates.
Bump and Normal Mapping
Enables bump and normal map rendering in images created with Info Channel renders.
Wireframe Backface Highlighting
Enables the highlighting of back-faces in the wireframe channel.
Sets the maximum distance of the spread of ambient occlusion shading
Controls how many samples are calculated in parallel. Smaller values require less memory to store the samples state but may cause the render to be a bit slower. High values require more memory but can reduce render time. The change in performance depends on the scene and the GPU architecture.
Max Tile Samples
Controls the number of samples per pixel that Octane will render before storing the result in the render buffer. A higher number means that results arrive less often in the film buffer.
Minimize Net Traffic
Distributes only the same tile to the net render slaves until the max samples/pixel has been reached for that tile and only then will the next tile is distributed to slaves when enabled. Work done by local GPUs is not affected by this option. This way a slave can merge all its results into the same cached tile until the master switches to a different tile.
AO Alpha Shadows
Takes the opacity of the surface as determined by its shader into account when rendering using the Ambient Occlusion info channel. Ambient Occlusion shading is based on the opacity of the surface.
Sets the opacity value minimum of the surfaces when rendering with AO Alpha Shadowing enabled.