Indigo Renderer Forum

..not an essential one, but should be useful for some of us to have an alpha map optional output, showing in black the plane sky areas and in white anything else!

Does it sound possible and/or useful to anybody here (excepted me)?

This can be simply done by using your main 3D app,
rendering an Mask or your alpha map should be possible there in seconds
with some few clicks... merging this mask/alpha Map with Indigos rendering output in the gimp or PS should get fast too...

..sorry Zomb..
I didn't get what you mean..

He means, since you model your scene in some 3d app (I'm assuming you don't model in indigo's xml... ) you can render the scene in that program, with alpha output, and just use that. I dunno which program you use to model, but it shouldn't be too hard to figure out.

yes, exactly alex... sorry for the confusion, english isn't my native language

Heh, no problem. (actually, you do fine, I can understand your post ok.)

Some minor mistakes (as in everyone's posts), but fully readable

..sorry..
i didn't understand perhaps because i use SketchUp as a modeler, so i can't do any rendering of the scene with alpha map!

Sorry i didn't get it at first glance..

Pibuz wrote:..sorry..
i didn't understand perhaps because i use SketchUp as a modeler, so i can't do any rendering of the scene with alpha map!

Sorry i didn't get it at first glance..

You can do an alpha render with SU (kind of..)

1) Change your background color to 100% white
2) Change your front face and backface color to 100% black
3) Switch to monochrome face style
4) Export the image and edit it (invert) if required

There is a way to render alpha using SkIndigo monochrome mode too:

1) Change your background color to 100% white
2) Create a 100% black diffuse material
3) Change your render settings environment to 'SketchUp Background Color'
4) Switch to monochrome face style
5) Render the scene - hint: use camera tonemapping to get a pure-white background
6) When asked what material to use for monochrome render, select the 100% black material
7) You might have to do some post image editing of your render (contrast, invert) to get the final alpha image you want.

It's an annoying workaround -- especially with scenes with a lot of geometry, that take a while to render. Also, it can be hard to match the depth of field settings in Indigo and in the renderer used to make the alpha channel -- particularly if the other renderer doesn't support non-circular apertures. The transparency of atmospheric effects (smoke, fog, etc.) would also be impossible to reproduce properly with another renderer. I really have to go with Pibuz on this one; any professional renderer should have an alpha output option, and Indigo is no exception.

Thinking about this request a little more,
the ultimate goal is to composite Indigo-rendered images over an existing background, correct?

"Thinking about this request a little more, the ultimate goal is to composite
Indigo-rendered images over an existing background, correct?"

YES!



take care
psor

Ok, I'm gonna have a think about how to do this best.

Yeeehaaaa! Finally!

Thanx! ;o))



take care
psor

Ok, I've thought of one way.
It would involve two master buffers; I wonder if using 2x the amount of memory for the buffer than usual will be alright for people?