Author Topic: Reflection point still images (photo-mode)  (Read 1396 times)

Lars

    Reputation: 12
Reflection point still images (photo-mode)
« on: October 10, 2011, 03:16:58 pm »
October 10, 2011, 03:16:58 pm
How do I set the reflection point for images in  photo-mode?

I'm having trouble setting up some still images renders. The reflection of the windows doesn't seem to work, it's just a dark grey area.
When setting up the reflection point in movie mode switching back to build then photo mode, the reflections show a bit of clouds as it should be. But after pressing the generate photo buttons these reflections disappear when generating the image?!

I hope it's clear without example images.
Version SP2 build7.

Re: Reflection point still images (photo-mode)
« Reply #1 on: October 10, 2011, 03:25:04 pm »
October 10, 2011, 03:25:04 pm
It's difficult to say without seeing the scene (and in particular where you place the custom reflection point with the "Reflection control" effect).

In any case, the way to ensure that the reflections use a custom reflection point is to apply a "Reflection control" effect to your clip in Movie mode. Then select "Custom Position" and click on "Set reflection point". Move the camera to the position in your scene that you would like to use for the 360 degree reflection map, and click on "Back".

It sounds like you're already doing this, but perhaps you're not placing the custom reflection point in a suitable place? Try moving the position of the custom reflection point to various places in your scene. In some cases, you're also better off with "Land + Sky" reflections instead of "All objects".

When you're happy with the way the reflections look in Movie mode, go directly to Photo mode, since this mode "inherits" the effects/weather settings of whichever mode was last active (ie, Build or Movie mode).

In Build mode, reflections are only updated (once) when you change the weather settings. Alternatively, you can press (CTRL) + U to update the reflections manually. Build mode relies on the camera position for reflections, and all objects are reflected by default (well, apart from certain particle effects, but that's a known limitation). For that reason, some situations will require the "Reflection control" effect in Movie mode, since it allows you to choose whether you want a custom reflection point or not, and whether you want all objects to be reflected or just the land and sky.

Lars

    Reputation: 12
Re: Reflection point still images (photo-mode)
« Reply #2 on: October 11, 2011, 01:50:58 pm »
October 11, 2011, 01:50:58 pm
It got it to work.
I think the step I made going through build mode was not correct.
When switching from movie mode directly to photo mode the reflections stay the same.
It's still a bit of a struggle to get the right look though. Much to be improved for future versions!

I switched to build mode first because I wanted to use the image presets. Now I just make these presets as different movie clips with the reflection control attached.

Thanks Morten!

Re: Reflection point still images (photo-mode)
« Reply #3 on: October 12, 2011, 09:14:39 pm »
October 12, 2011, 09:14:39 pm
Reflective cans like in that video would require 3 separate 360 degree reflection maps from positions at the centre of each can. At the moment, Lumion only uses 1 x 360 degree reflection map rendered either from the camera position, or from a custom position if you use the "Reflection control" effect in the Movie section.

A reflective floor would require a different technique known as planar reflections :) In Lumion, this means that the 3 cans would have to be rendered twice (the second time mirrored). If you have a large scene with lots of objects, it can have a dramatic impact in performance which is why you really only see this technique in scenes with few objects.

If you combined planar reflections with separate 360 degree reflection maps for reflective objects the result would be a reasonably realistic approximation (but still not perfect raytraced reflections).