[polynurb]

when doing a montage on a backplate image, it would really help if it was possible to get fire with masked background so we see a correct preview of the composite image.

i am not sure if this more a plugin or core issue though...

thanks,
daniel

[JDHill]

Sorry, it's not supported by the render engine. Part of making Fire fast is cutting out all the conditional logic associated with render channels, so I doubt you'll ever see this.

[polynurb]

thanks for the fast response..

what about doing it the "cheap" way.. like via HDR background channel load a certain (pure rgb) color, which could be used on the plugin side to read it out and create a mask for the overlay in rhino? ..in theory

[JDHill]

I guess I don't understand -- are you asking for this so that an alpha image would be shown by the plugin, overlayed on Rhino's viewport? Please let me know more precisely what you are trying to do.

[polynurb]

ok.. sorry; i'll try to be more on point:

right now, i am trying to fit a 3d bridge onto a photo of an existing landscape.
the bridge is quite small if seen on the background bitmap/wallpaper on the screen. (wide angle lense, far away)

i have to fit exactly the paths streets etc. from the 3d geometry to the back plate but i can hardly see what i am doing as on screen it shows only a few pixels wide.. and i can't zoom in because rhino's background bitmap is static.

the actual back plate is very large at 8k. so if you zoom in photoshop there is lot of detail i can't see if i fit everything on screen.(like in the rhino viewport)

i just thought of that idea because you have some way of defining the fire-overlay we see on screen;
thought it could probably be clipped by a mask coming from the image just being rendered.. if it can't be done internally.

*with fire the rendered area could be much smaller, maintaining the camera/viewport setting, thus showing all details necessary to see.


"cheap green-screen":
a- background HDR channel "pure Green"
b- "screenshot" through the film size rectangle in the rhino viewport area catching background bitmap
c- pure green is continuously read by the plugin while fire is rendering
d- a realtime mask is used to clip the fire output
e-the background bitmap is revealed in the clipped parts of the fire preview.

hope it makes sense now..

daniel

[JDHill]

I still don't quite understand. Let's pretend the plugin could do your greenscreen, and you are looking at this bridge you've modeled in Rhino. You put a green MXI in your IBL background, start Fire, and enable the viewport overlay. The plugin cuts out the green background, such that you see a Maxwell-rendered bridge in your viewport, overlayed above your Rhino OpenGL-rendered bridge*. No matter how you move your camera, Maxwell-rendered pixels cover your Rhino OpenGL-rendered bridge; elsewhere, you see OpenGL-rendered pixels, whether they contain Rhino wallpaper, background bitmap, or just 3D space. This being the case, I don't understand how the greenscreen feature would help you accomplish your goal. If I understand correctly what you want to acheive, it seems more like you need a viewport zoom feature, which does not affect the 3D view, and instead zooms/pans in 2D, in and across the view's image plane. Basically, a blow-up region feature for the Rhino viewport. Please let me know if/how I've misunderstood your scenario.

* this assumes alpha bitmaps are supported for overlay; never having tried to use one, I'm not sure if that's the case.

[polynurb]

Basically, a blow-up region feature for the Rhino viewport.

exactly, and fire, or to be more precise the fire window being the compositor.
-because that window can be scaled up and set to highest quality. and the plugIn could read the background from the original wallpaper, so all the available resolution would be seen.

ok, geometry changes need and relaunch, but if it is more about fitting separate elements, other geometry can be turned off, so that reload would be quite fast.

but even leaving the modelling/fitting issue aside, it would be great to see the final composition in the fire window.
because rendering it out in full maxwell doesn't help either.. so that part of the work, if working with back plate images is not very interactive, because one can only see the whole thing much later in PS.

[JDHill]

Now I get it, you want the Rhino wallpaper composited into the background of the fire window. Then, you will use pick film size rectangle to simulate the blow-up feature. The problem is how to place the Rhino wallpaper behind the now-clipped fire image in the fire window, because the image in the fire window is what the camera's film sees. So the wallpaper image needs to be zoomed/panned according to your film size/offset, as compared to the theoretical Rhino viewport film size. And after all that, you are still limited to +/- 100% lens shift in the pick film size rectangle tool.

I have to say, this would be way too much messing around for far too little benefit, and this, when the feature you are actually looking for, 2D viewport blow-up, is not related to Maxwell at all, and is something that would more appropriately exist in the Rhino viewport itself. Best case, you would actually be able to set one viewport to show the zoomed/panned image of another; in other words, given this camera (in blue), with wallpaper set, you could set a different viewport to interactively show the small rectangle:

• 

[kami]

I've got another request which comes along similar:
I often use the fire render to check if the perspective matches the photo (usually i overlay it with 50%, so I don't have to cut out any background as in daniels request). This works pretty fast, as I can adjust the camera, copy the new image into photoshop until i've got it right. There only is one step which is quite annoying: Every time I want to have my fire output in photoshop, I have to save it as a file and then open it in Photoshop. It would be a great help, if you could just copy the image from the fire window to the clipboard and then paste it in photoshop, which would be much faster. Would that be possible to implement?
Thanks, Christoph

[JDHill]

Yes, that is a good idea, and should not be too difficult to implement.

[polynurb]

this is what you can use in the meantime, great application in anyway:

http://getgreenshot.org/

you can assign a hotkey for re-capturing the same part of your screen > don't move fire window

-daniel