Can anyone explain vrayMultiProjection?

[dougWilkinson]

Hi all

is this a tool to aid matte painting projections?

doug

[vlado]

It blends the result of several different projection nodes based on the distance from the projected camera. Optionally, it can also take as input a z-depth image for each camera to take occlusion into account. If you are interested, I can post a sample scene.

Best regards,
Vlado

[dougWilkinson]

Hi Vlado

This does sound useful. Its hard to imagine how it works without seeing it setup. We may experiment with the node but a sample scene and any thought on the practical purpose of this node would be good. We can imagine using this to project multiple views of the same setting onto the same geo, using different cameras. does that sound right?

[bigbossfr]

Hi Vlado

This does sound useful. Its hard to imagine how it works without seeing it setup. We may experiment with the node but a sample scene and any thought on the practical purpose of this node would be good. We can imagine using this to project multiple views of the same setting onto the same geo, using different cameras. does that sound right?

I have used it :
- i have rendered a lot of spherical camera
- after, i have added all rendered images into this node, and projet all renders in my scene.

All projections were blended. Big camera mapping, fast render.

[dougWilkinson]

ahhh. that sounds really neat. would like to try that on a city block with some HDRs from lots of angles!

doug

[vlado]

I have used it

So did you end up using it for final shots eventually, or you did something else?

Best regards,
Vlado

[bigbossfr]

So did you end up using it for final shots eventually, or you did something else?

Best regards,
Vlado

I have used it for 1 shot (camera movements (columns) were a big problem for others shots), and it works ^^.

[UdushKudush]

Hi! Can anyone post sample scene please?

[hsz]

Vlado is possible to see an example please? Thanks

[vlado]

Yes, let me find it...

Best regards,
Vlado

[vlado]

Here it is:
https://ftp.chaosgroup.com/vlado/vra...multi_proj.rar

The scene has two layers, the master layer uses the VRayMultiProjection node to render the geometry, while the layer1 layer is set to produce the spherical projections (you need to render each of the three spherical cameras in turn).

The "zdepth offset" parameter can be used to deal with artifacts that sometimes appear when blending the different projections.

Let me know if you have any questions.

Best regards,
Vlado