Rhino7 Cycles Rendering Start Delay: Contributing Factors List

In this thread, we’ll discuss the notable delays observed in the starting times of Rhino Cycles rendering.

  1. Invert: Form 12~ seconds to 0 using Photoshop.
    Bug Report: RH-75378
    A primary contributor to this issue appears to be the inversion of glossiness textures to roughness textures, which is a process inherent to the PBR Metallic workflow utilized by Rhino Cycles. Every texture using the inversion option in the texture color adjustment section adds approximately 15 or more seconds for a 4K image to the rendering start time. This can lead to significant delays when multiple textures are involved.

    [SOLUTION] Use Photoshop to invert the texture image.

  2. Gray: Form 11~ seconds to 0 using Photoshop.
    [SOLUTION] Use Photoshop.

  3. Clamp: Form 10~ seconds to 0 using Photoshop.
    [SOLUTION] Use Photoshop.

We will list these and other factors contributing to increased start times. And explore potential solutions to streamline the process.

basically, you are enumerating specific examples of a more general principle: when you use a procedural texture, or a decal, or request alterations to a bitmap texture, or especially, use the WCS/OCS mapping modes, rhino is going to bake textures to facilitate what you have requested

you can find the baked textures showing up here:

as you are finding, to avoid this, you have to avoid asking rhino to make such changes (invert, clamp, etc), and avoid creating scenarios that require per-object textures