Render Selected not visible to Cameras

[grasshopper]

Being able to used viewport selection or Object ID as a selection for rendering with the selected object set to invisible to camera would be awesome for patch rendering and fixing animations.

We use xrefs to build up our master scenes so don't have geometry in our render scenes. The ability to drop some geometry into a render scene and use it as a mask for rendering selected on ID would allow to render a very specific areas through an animation. Currently if renderable is unchecked or invisible to camera is set in the properties that object cant be used as a selector. This would allow you to create geometry larger than your target to include shadows and GI, you could link such an object to animated models in your scene and re-render allowing enough render data to feather results into previously rendered footage.

Hope this makes sense. :)

[maru]

I am not sure if I understand this request correctly, but so far I was able to come up with just one workaround: creating a material with full refraction and 1.0 IOR. It will show objects behind it when it's used as the render selected > viewport selection.
It is possible that it would require further tweaking - for example using the rayswitch material to only show this transparent material directly, and excluding it from reflections, refractions, GI (I am not sure about this though, since technically it should be completely invisible to all rays).

[Frood]

The ability to drop some geometry into a render scene and use it as a mask for rendering selected on ID

So you would like to have both? Area rendering and selected only? Assuming you have everything animated (moving objects + moving cam) you could:

- Xref the object of interest from one of your xref scenes additionally into your main scene
- Set it's renderable property to off
- Create a sphere with a radius covering the area you want to render
- Set the spheres renderable property to off (and "See-through" to on, makes it easier)
- Align and link the sphere to the xref object
- Use "Area to Render" -> "Region" with "Auto Region Selected" ticked in render setup
- Select Sphere
- Render sequence

Additionally you now could add Corona Object GBuffer ID render selected feature to mask the object(s) (by setting the object ID in the xref scene).

Problem with all "selected" methods is: you cannot send the scene to a farm. In this case I would try the workaround maru mentioned but using the Include/Exclude list feature instead.


Good Luck

[grasshopper]

Hi Guys, Thanks for your responses, sorry it has taken me a wee while to look back at this.

Frood, you are right it needs to work on a scene with everything animated. They are heavy complex scenes too hence trying to save time on rendering patches in. I had never tested with the auto region select, in fact its not a feature I have every used before. Would work well but it does need to work on a network render.

I have been testing this for a while and never came up with a satisfactory solution. I was setting refraction to 'thin' thinking it was the same as 1.0 but it would then render nothing. Setting full opacity would render nothing too. I found that setting visibility to 0 in obj props rendered nothing too but now after looking at your suggestions and with further testing I must of been combining that with zeroing the refraction.

What I find now is that unless refraction is turned up from 0 neither opacity or visibility work but as long as refraction is at 0.001 or above it will render the selected objects area so I will progress along this route with a full test animation and see how it works.

I still stand by my feature request though a simple dummy render object in scene would be awesome it could even have a fall off for feathering in in post.

[Frood]

as long as refraction is at 0.001 or above it will render the selected objects area

Yes, your material should look like Maru mentioned: Opacity 1, IOR 1, and "Thin" unchecked. In the object properties disable "Visible in Reflection/Refraction and "Cast Shadows" (you could do that with a rayswitch material as well). Then add the object to the include/exclude list in "Render selected" from Corona scene setup and it should work even as a network job.

I also see the need for a better solution, it's just a bad workaround. And as soon as you want some render elements, you are lost anyway with this method (v6 will probably solve the latter).


Good Luck