Hi, just evaluating Vray for Blender for the moment, I wanted to ask 2 questions:
1. When watching tutorials for Vray for Max, for example, there’s not just the Frame Buffer during rendering, but another window as well, that shows a progress bar, estimation of remaining time, but also allows you to recompute just the denoiser pass with new settings. Is there a way to get this in Blender as well?
2. I’ve seen, that it’s possible to get object and Material ID as color passes, also to randomize the colors, but unless I get the ID output as a B&W pass for a single ID, or at the most as a color pass, that contains at most 3 different IDs in the R, G and B channels respectively, the borders of the masks stop working and I get fringes around objects, when I try to mask them by extracting the mask from a colored ID pass. So is there a way to output a B&W pass for every single object and material ID?
Hi bdancer, thanks for your reply.
Is there another way to re-compute the denoiser pass only after the render is finished? Also, is it possible to stop a progressive render a a desired time and let the Denoiser do it’s magic afterwards? Right now, if I’m not mistaken, if I stop the render, the Denoiser pass doesn’t get computed
Basically, here’s what I’m trying to get. I have a render and want to mask a part of it for post-production, the stone path, in this example. It’s as easy as applying the the output as a mask directly and works perfectly. This example was made in Modo, where I can attach a render output like this to every single material, or create masks like this for items or groups of items. In vray, I only managed to get a single pass so far, that outputs all of the available IDs as random colors. so in this example, I would get… let’s say for argument’s sake a purple color for the grass and cyan for the stones. Now I could use the magic wand in photoshop, or select by colour, but the few antialiased pixels on the border of these two areas are going to be very problematic to select correctly. In Vray, I’ve come across the option to set the ID color, which would allow me to set the desired colors to R, G and B, this would allow me to get 3 separate greyscale masks out of one output, one per channel, but I would have to make sure, that all other IDs are black, otherwise, if I got a random Orange next to my Red channel, the Red component in the color Orange would mess up my Red mask. But even if this worked, I could only get 3 mask per render, but if the scene is more complex, I’d have to re-render it a few times to get all the masks I need for post.
Material ID colors are black by default, so change them for materials you need to get BW material pass. Or postpro, just BW the whole material render pass.
And there is a max.render time value to stop render.
As for the Material ID Color, that would mean, I would have to manually set up the scene, so that only the materials I want in my mask are white, all others are black. Also, I’d have to re-render the whole scene for every mask I want to use in comp.
The MultiMatte node seems to be very close to what I’m used to. I can also imagine using just one color channel per node, which would allow me to output properly named masks directly from vray while rendering the scene just once. The conversion of the designated channel to a greyscale mask could probably be done in post… haven’t found a way to do this in the Render channels node tree yet. I could also imagine a script, that would look through the available IDs and create the correct amount of output channels set to the corresponding IDs.
One thing that I ran across though, is that currently, the border between an Object and the scene Background doesn’t seem to get antialiased in the MultiMatte channel, while it works for borders between 2 objects. Is there a setting I’m missing?
Thank you very much in advance.
EDIT: ok, AA against background seems to start working if the background isn’t completely black.
EDIT2: setting the background to a dark grey fixed the AA sampling around the background border regions, this in turn revealed some problematic areas in object/object borders, those disappeared, when I changed the Sampler Type from Progressive to Adaptive DMC.
There’s a tool to automatically assign a random material ID color to standard materials, so if you use the standard material node, that’s a nice time-saver. (Seems you have to press the randomize material ID button more than once to get it to work, or do another command before the color shows up.)
