Point Cloud sRGB

V-Ray V-Ray for 3ds Max General
1

Hi,

I need to render some pointclouds imported from Autodesk ReCap. When I get them into max they look perfect on screen.

When I render them they look washed out, switching off the sRGB curve in the frame buffer displays the colours correctly There are no lights in my scene

I need to render the scene with other objects created in Max. Is there a way to change the colours in the point cloud or it’s material

I’m using Max 2021 and VRay Next

-Garry

2

Can you get the RGB channel of the point cloud to run through and output node somehow? You could change the gamma in there to 2.2 or 0.54

3

Also I can’t get the Pointcloud to stop casting shadows. Even if the light is set to ignore the point cloud it still casts shadows.

If I apply A VRay material to it it’s fine (But I loose the RGB data, which is important).

Is there anyway to keep the RGB and retain the features of a VRay material (properties etc)

4

Would you have a piece of that PC to share?

5

I tried to do this a while back but could find no way to get the results I wanted with Vray.
This is an old post about the same issue…still unresolved Point Cloud Rendering - General - Chaos Forum

6

Hi Lele,

I’ve sent you a link to the Point Cloud.

Thanks

7

Sent you the file.
In general you’ll need a “VrayPointCloudColor” texture to pick up the PC color, and then you’ll want to feed that to a V-Ray shader of your choice (VrayMtl, LightMtl, PointParticleMtl).
Any issue with gamma, can then be cured with a CC node, if needs be, after the VrayPointCloudColor texture.
Seemingly, with a v-ray material assigned to the PC, shadowing exclusion from the light works fine as well (i forgot to mention this in the message i sent you.).

8

Hi Lele,

Thanks for the input that seems like what I need.

However I don’t have “VrayPointCloudColor” so I think that I need VRay 5 to get this to work (I’m still using VRay Next)

This could be the excuse that I need to upgrade.

-Garry

9

Argh, i didn’t realise that that was the case.
I promise, i wasn’t trying to get you to buy V.5.
Not like i’d be complaining if you did… ^^

10

Cool that it works now though :slight_smile:

11

Hi,

No problem upgrading to VRay 5, it was always going to happen, just a case of when.

Thanks for looking into this for me.

-Garry

12

I also had washed out colors. I only created a VRayMaterial with VRayPointCloudColor in the Diffuse slot and played arround with the values. In my case (a LAS Pointcloud with RGB values) I got a render which was very near to the viewport colors when I changed the “Output amount” to 1,3 and the “RGB-Offset” to -0,25