Render Item: mPath Renderer Settings

Allows you to create and save custom render settings as presets to reuse in other scenes.

• Store Preset - Stores render item channels as a preset. Only selected channels are saved. To select channels, open the Channels tab and Shift or Ctrl/CMD+click on the channels you want to save.

• Remove Preset - Removes the render preset. Built-in presets cannot be removed.

When Renderer is set to mPath, this allows you to choose whether to use a CPU only, or a GPU ray tracing engine. The following options are available:

Note:  A warning icon appears next to the following options if they are not available on your current hardware.

• Foundry SSE (CPU) - Uses only the CPU for ray tracing.

• Intel Embree (CPU) - Offers increased performance for CPU ray tracing, providing you have an Intel processor that supports SSE instructions. See Intel Embree for more information.

Note:  Deformation Motion Blur is currently unsupported with Intel Embree (CPU). An "unable to create Embree scene" warning appears if you attempt to render with this features using Embree. Use Foundry SSE (CPU) if you require these features.

• NVIDIA OptiX (GPU) - Offers increased performance, allowing for multiple buckets to take advantage of GPU raycasting simultaneously.

Note:  If you see an "Unable to create context" warning while trying to render with Intel Embree (CPU) or NVIDIA OptiX (GPU), it may imply a driver or hardware issue. See Intel Embree or NVIDIA OptiX to check for updated driver and hardware support.

Note:  Modo is using the OptiX 7 ray tracing engine. Transform motion blur is supported by this engine, but deformation motion blur is not currently supported.

Tip:  The NVIDIA OptiX option works on non-RTX cards, however true RTX hardware shows increased performance over non-RTX. Be sure to download the latest NVidia drivers, version 435 or higher.

Antialiasing primary quality control. Specifies the minimum and maximum number of samples per pixel. The renderer iterates through a series of passes. When Maximum Quality is set to a low value, you get a quick first iteration, providing a noisy preview of the scene.

Allows you to choose different antialiasing filters. The Antialiasing Filter determines the pattern to use when evaluating a pixel. The default is Gaussian, which performs very well in most cases, and offers a good balance of performance and quality. The other options are:

• Box

• Triangle

• Catmull-Rom

• Mitchell-Netravali

Tip:   Catmull-Rom generally yields slightly sharper results than Gaussian, while Mitchell-Netravali offers good results when dealing with problematic moiré (created by fine texture patterns).

Note:  The Antialiasing Filter option may be hidden. Click the More button at the bottom of the panel to display all controls.

Specifies the degree of noise that's acceptable to determine when a pixel is skipped. If a pixel inside a render bucket achieves a satisfactory level of refinement, it is skipped for each additional iteration, speeding up the render. Higher values lead to faster but noisier renders.

Tip:  The default value of 5% is recommended, however 10-20% can be acceptable if denoising is applied afterwards.

Specifies the maximum number of bounces for Diffuse rays before they are automatically terminated. Higher values increase render time but produce more accurate results.

Specifies the maximum number of bounces for Reflection rays before they are automatically terminated. Higher values increase render time but produce more accurate results.

Specifies the maximum number of bounces for Refraction rays before they are automatically terminated. Higher values increase render time but produce more accurate results.

Eliminates rays that have little or no impact on the final rendered image. As rays are fired, they are assigned an importance value. This value can increase or decrease at each bounce, depending on the surface values contribution. If a ray's importance value falls below the Path Threshold, Modo decides whether to kill the ray or trace it further. Increasing this value can decrease render time at the cost of quality.

Note:  The Path Threshold option may be hidden. Click the More button at the bottom of the panel to display all controls.

Controls the Maximum Radiance carried by secondary rays. This can be helpful in reducing noise and preventing fireflies (single bright pixels) caused by small but very bright features of a scene, such as tight specular highlights or surfaces very close to point light sources.

It acts as a multiplier for the most highly-exposed render output in the scene. Setting the Maximum Radiance to 10.0 (the default value) means that a ray is ten times brighter than the brightest render output. It is recommended to keep this value above 1.

Note:  The Maximum Radiance option may be hidden. Click the More button at the bottom of the panel to display all controls.

Toggles the Adaptive Subdivision function in Modo. When enabled, Modo adaptively tessellates all SDS meshes at render time. Which is to say, depending on the user settings, the mesh is refined repeatedly until all polygonal edges fall within the set subdivision rate.

When an object's surface has displacement applied in the Shader Tree, this checkbox toggles the rendering of micropolygon displacement on a global level.

When Micropoly Displacement is enabled, the Displacement Rate, sets the threshold to which the geometry is subdivided into micropolygons. Similar to the Subdivision Rate, micropolygon displacement is adaptive, evaluating every polygon edge separately.

The distance from the camera to the center of the edge (the focal length), and the render resolution are used to convert the Displacement Rate (in pixels) into a distance in world space. If the edge is longer than this and also longer than the Minimum Edge Length, it is split in half. This process continues recursively until all edges satisfy those requirements.

Note:  The Displacement Ratio option is hidden by default. Click the More button at the bottom of the panel to display all controls.

When set to 1.0, objects are tessellated a consistent amount across their entire surface, but when displacing large areas, such as a ground plane in an environment, where a good deal of the geometry lays outside of the view of the camera, most of those polygons are going to waste, filling up your system's memory. The Displacement Ratio reduces the number of displaced polygons outside the camera's view. The higher the number, the greater the reduction in polygons. Keep in mind though that reflective and refractive objects still are able to see these areas outside the camera's view, so high settings may begin to introduce artifacts to your image.

Note:  The Minimum Edge Length option is hidden by default. Click the More button at the bottom of the panel to display all controls.

Each edge in the mesh is tessellated until polygons satisfy the Displacement Rate setting. Ungoverned, this can go out of control resulting in ridiculous numbers of polygons. The Minimum Edge Length sets a minimum length for any polygonal edge. Once an edge has reached that minimum length it can no longer be split. A simple and effective throttle for controlling the amount of polygons in your scene.

Note:  The Smooth Positions checkbox is hidden by default. Click the More button at the bottom of the panel to display all controls.

When a surface is diced into micropolygons, the initial positions of the micropolygon vertices lie on a curved surface based on the original smooth vertex normals. So, if you start with a regular non-SDS sphere, for example, it'll be diced into a smooth sphere, and then the displacement texture is applied to that. You could even use this as an alternative to subdivision surfaces by just applying a displacement texture that is zero everywhere (although the resulting surfaces are different from SDS in that they actually pass through the original vertices).

The ability to turn off position smoothing, which means that all the initial positions of the micropolygon vertices lie exactly on the flat planes of the original polygons. Doing this in the non-subdiv sphere example would cause the diced version to look faceted. The reason this feature was added was that it's necessary to turn off position smoothing when using a displacement map created by object-to-object baking, since the distances in the map are measured based on the original polygons of the low-poly object and not the smoothed polygons.

Note:  The Displacement as Bump checkbox is hidden by default. Click the More button at the bottom of the panel to display all controls.

When this option is enabled, Modo also applies any displacement maps as a bump map, providing a finer detail evaluation that requires lower number of subdivisions to achieve. This can be used to reduce the amount of memory necessary to render complex scenes when combined with lower subdivision rates.

Note:  The Indirect LOD checkbox is hidden by default. Click the More button at the bottom of the panel to display all controls.

When this option is enabled, Modo holds an additional lower resolution version of displaced geometry used strictly in calculating indirect lighting, reducing overhead in global illumination calculation. However, it may end up using slightly more memory as two distinct copies of the same geometry may be held in memory simultaneously.