Hi,
I want to project a video on a plane - no problem (e.g. video as texture).
But: How can I project a video on a plane like a beamer? That is, if actors walk between the beamer (source of light) and the plane through the beams, the video should also be partially visible on the actors and other objects.
Does anyone have any ideas?
Greetings, Ulrich

Interesting problem.

What you can do is create a Spot Shadow, which is a spotlight that only produces a shadow.

https://manual.reallusion.com/iClone-8/Content/ENU/8.0/20-Scene/Light/Shadow_Caster.htm


Adjust it so that the shadow is cast on the screen. It would not completely block the light from the screen so I don't know how will it works.  

Another idea is to render just the shadow on a white screen of the same proportions as your video and place the resulting video in the Blend channel, set to Multiply. The black will suppress the image from your video.

https://manual.reallusion.com/iClone-8/Content/ENU/8.0/30-Set/Video/Applying_Videos_into_Texture_Channels.htm 

---

Hi animagic,
thank you very much for your quick reply.
I will try it  - and report.
Ulrich

Hi animagic,
it's a pity I wasn't successful. I probably made a mistake or misunderstood something. My test setup:
Horizontal plane as floor, vertical plane 16:9 with an image, cylinder as moving object (later), spot shadow caster.

Your suggestion 1: The shadow of the cylinder is cast on the vertical plane; the cylinder does not receive an image section as would be the case with a beamer.; nsert the image as a texture of the cylinder; the UV adjustment would be extremely complex for a moving cylinder (screenshots #1 & #2)

Your suggestion 2: Shadow (with shadow caster) on a white screen (screenshot #3); "...render just the shadow on a white screen of the same proportions as your video and place the resulting video in the Blend channel, set to Multiply. The black will suppress the image from your video." I do not understand what to do: How can I render just the shadow?

I also tried to solve my problem with the "Signal Light.iProp", replacing the bat with another image - no success so far.

Nevertheless, thank you for your suggestions, Ulrich

I see. Of course, the video projection would be on the object blocking the screen. I didn't think of that and would not know how to do that...:unsure: 

---

Well, is this something like you are looking for?

If so, I'd assume that it can not be done in iClone because, AFAIK, iClone does not use real ray tracing.

I put together this little video in Cinema 4D: a single light is projecting the image with the car onto a vertical plane with a few objects moving in between the plane and the light. The objects have different materials. The figure has a non-shiny material and the bucky ball is reflective; both cast solid shadows whereas the pyramid is semi-transparent (so some of the projected light still hits the plane).


My YouTube channel: Animations made with Cinema 4D and Reallusion Products

Hi Nirwana,
that would be the result I need. Too bad it doesn't work in iC.
Thanks for th hint.
Greetings, Ulrich

Hello, I've been thinking of how to do this and came up with a partial solution (your mileage may vary) using a GI Emissive Plane - Square as the 'projection source'. 

• I scaled the GI Plane to match the 'Screen' dimensions, then loaded the video into the Diffuse channel (make sure you have 'Emissive Side' selected in the Materials tab)
• Go to 'UV Settings' and flip it horizontally (otherwise it 'projects' a mirror image)
• Start with Self-Illumination at 100 (you can always back this off)
• IMPORTANT!  Set GI Plane as 'Dummy'.  It will still emit but won't be visible in the scene

For the Screen:

• Scale a plane to 16:9 and imported the video to the Diffuse channel, with Self-Illumination set to 100

Reallusion Certified Director / Reallusion Best Visual Award / Reallusion Certified Content Developer
See all the G-Tools Plug-Ins available for iClone here: G-Tools Plug-Ins

I have made it with UV projection.
Unfortunately, it's only good for a single material object where object texture does not matter much.

I used cylinder in this case.
First I unwrapped the cylinder "projected from view" in Blender and placed it's UV in one corner (preliminary applying a video to the diffuse channel so that I could estimate proper placement).




Then in iClone applied the same video to a plane and cylinder.
Moved the cylinder in front of the plane screen at the timeline.
Also applied some bump map to the cylinder as well to stop the illusion that cylinder is rotating.
Finally at the end, when cylinder stops, I set the offset by U to the value of -0.9 (could be positive or negative depending on the direction).
This is done for the diffuse channel only. The value itself controls where at the map to stop sliding the texture (video in this case).





I use a single directional light with strong shadow.
Spotlight with volumetric for a beamer.
Camera placement and angle also play an important role and should be figured experimentally.

Thank you very much (gordryd & 4u2ges) for your interesting suggestions. I will try out and report the results.
Unfortunately, I don't have enough in-depth experience yet (and I'm not that fast anymore); so it will probably take a while.
But it is very encouraging for me to receive professional help from users here in the forum so quickly.
Thanks a lot.
Ulrich