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Messages - karnak

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General Discussion / Re: Names of corona map types
« on: 2019-04-25, 12:31:56 »
I'm glad I could help you!

General Discussion / Re: Names of corona map types
« on: 2019-04-25, 11:53:02 »
I haven't thought about the implications of your request, but I have two workflow suggestions.

The first suggestion is that you can type c*b to quickly find a CoronaBitmap map in the Material/Map Browser's search field.

The second suggestion requires some preparation. Open the Material/Map Browser's drop down menu and create a new material library and name it for example favourites.mat, then drag and drop in this new library a CoronaBitmap and rename it as CBitmap. You can now type cb to quickly find a CoronaBitmap map.

General Discussion / Re: VrayuHDRI map rotation
« on: 2019-02-25, 09:42:06 »
I would also open the Curve Editor and double check what's going on with the animation curve associated with the VrayHDRI map.

To move a window between screens I use Win + Shift + Left/Right Arrow.

Feature requests / Re: The most wanted feature?
« on: 2019-01-02, 10:09:01 »
Thank you lolec, I think your message has very good insights and is very respectful of both consumers and the development team.

Interesting findings Juraj, thanks for sharing.

During a project early this year, I also found out something.
I was testing my project for performance and found out the following:

Code: [Select]
    CoronaBitmap    8bit image   38 sec
    CoronaBitmap   16bit image   46 sec <<<

(Default) Bitmap    8bit image   41 sec
(Default) Bitmap   16bit image   41 sec

This measure was taken (average of multiple measurements) by looking at the UHD cache precom time, the loaded images were in TIF format but I can't find in my notes how many channels. Corona was version 1.7.4.

Work in Progress/Tests / Re: dubcats secret little hideout
« on: 2018-09-28, 19:41:55 »
That would be extremely cool to have.
What X-Rite device you have? I can help you on the software side if you want to read some surfaces.
I know it's not the same as BSDF scanners, but at least it's something.


I forgot to say that I get the same values with calibrated polarised photography and with spectrophotometer with manual removed specular.

What happens outside F0 is a totally different matter though and depends on other factors, some of them are well approximated by the BRDF models used inside the shader, others are not.

Work in Progress/Tests / Re: dubcats secret little hideout
« on: 2018-09-28, 18:52:24 »
I'm not sure about the libraries, but in my previous example what I get from the instrument is the energy that the surface reflects, without distinction between diffuse reflection and specular reflection. Therefore to get only the diffuse you need to subtract the specular reflection and you can do this easily if you know the IOR of the surface (and if you don't care that much about it, you can just remove 4% which is equal to the energy that the default IOR adds).

I think a good way to remove 4% from RGB colors might be to use Lab mode and only work with the L component.

Work in Progress/Tests / Re: dubcats secret little hideout
« on: 2018-09-28, 16:32:22 »
I don't know much about these Nix products (first time I hear of them), but I have been using an X-Rite ColorMunki Photo to get diffuse values.

The ColorMunki Photo is a spectrophotometer that can sample the light spectrum from 380 to 730 nm every 10 nm (or every 3.33 nm in high-resolution mode).
In very simple terms, with the spectral data, you can get RGB values in a color space of your choosing (with appropriate illuminant, primaries and so on).

In my opinion, the data you get from this instrument is good enough, especially considering the price and the size of the device.
I say 'good enough' because the light spectrum is infinite, and with this tool, perhaps we are sampling the bare minimum visible range (380-730 nm) at the bare minimum interval (every 10 nm). I have read a lot of o literature on the subject, and this might lead to slightly inaccurate values in some cases. I feel I have already gone overboard with unrequested details, sorry. :)

Feature requests / Re: Camera modifier panel
« on: 2018-09-17, 17:08:50 »
I also think that something is not right, five seconds is too much.

Anyway, I want to mention that with maxscript you can change the CoronaCamera properties even if the Command Panel is in Create mode, and you can do this with only the camera selected, only the target selected or both.

Mostly the one below. The frames with the errors are not always the same.

Code: [Select]
Error: There are not selected any render elements that can be saved. You need to select at least one.

I also have random errors when working with CoronaImageBatch.BAT and CXR frames of an animation.
I edited the BAT file and added a pause at the end of each frame in the loop, and this reduced the error count.
Might this be related to the hard disk access?

It was an issue on my end.

General CG discussion / Re: Nvidia real-time raytracing
« on: 2018-08-30, 10:48:58 »
@burnin Thank you for the quote.

Work in Progress/Tests / Re: dubcats secret little hideout
« on: 2018-07-06, 15:04:08 »
Let's say that the color was sampled with a spectrophotometer. What you get from that instrument is one reflectance value that contains both diffuse and reflection (with no distinction). So, if you want only the diffuse you have to know the reflection value and subtract it from the value the instrument gave you.

When you read that you have to subtract 4%, it's because they assume the color was sampled from a non-metal surface with the default 1.52 IOR (that at normal incidence equals 4%).

What was the reason to use a point3 controller for the U and V offset in CoronaBitmap?

I was wondering the same.

I want to wire two seperate values to the U and V offset, but both of them use a single controller. So I can't connect up what I want, or is there another method?

You can still use a controller to manage your values separately (see attached image).

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