'Alias' material modifier questions...

radiance-general
1

Hello all,

So I hate to ask a stupid, basic question (yet again :slight_smile:
however I've read all I can, and not being able to find
a copy of the 'Rendering with Radiance' book anywhere,
this is the only place I can turn to.

I can't figure out what application the 'alias'
material modifier is for. I understand how to
apply modifiers, and patterns, and I've read the old
tutorial, the new tutorial, the help files,
and the man pages, and still can't get my head
around what this is for or where you would apply
it.

If anyone could point me to a help file,
or just give a few quick examples of what the
alias modifier would be used for in application,
I would be incredibly grateful.

Thanks a ton,

Jeffrey

2

Alias, in its basic mode, creates an additional name for a material.
I often use materials descriptions written in French. Without changing
the original file ids, I simply add a line:

!xform French_mat_file.rad

void alias red rouge
# modifier alias additional_id original_id

The function has additional benefits. If the alias command is modified,
only the new identifier acquires these modifier properties. I use this
method as a convenient way to combine picture data from a colorpict
description with a predefined material.

!xform picture_descriptions.rad
!xform paint_surfaces.rad

picturedata alias painting canvas

Of course there are other ways to achieve the same end, but when working
with several large material description libraries, I find that alias
provides the most convenient method.

-Rob Shakespeare
Indiana University

路路路

-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Jeffrey
McGrew
Sent: Tuesday, October 07, 2003 12:37 PM
To: [email protected]
Subject: [Radiance-general] 'Alias' material modifier questions...

Hello all,

So I hate to ask a stupid, basic question (yet again :slight_smile:
however I've read all I can, and not being able to find
a copy of the 'Rendering with Radiance' book anywhere,
this is the only place I can turn to.

I can't figure out what application the 'alias'
material modifier is for. I understand how to
apply modifiers, and patterns, and I've read the old
tutorial, the new tutorial, the help files,
and the man pages, and still can't get my head
around what this is for or where you would apply
it.

If anyone could point me to a help file,
or just give a few quick examples of what the
alias modifier would be used for in application,
I would be incredibly grateful.

Thanks a ton,

Jeffrey

_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general

3

First off, that you so very much in your clear
explanation of this. It was a great help!

Now I've got one other question, and then I
promise to leave everyone alone for a while
with my basic ignorance. :slight_smile:

When using RAD to generate Radiance .pic
files, I have experimented with the various
options and understand them on a basic level;
all but the difference between the
'Medium' and the 'High' quality settings.
I know that these change what options
are passed onto rpict, which I'm in the
process of learning more about, however
I'm unable to find documentation that
explicitly lists what options are changed
when one goes from the 'Medium' setting to
the 'high' setting. Seeing that I tend to
get awful artifacts and spotting whenever
I use the 'high' setting, things I feel I
could get rid of if I understood what's getting
passed onto rpict better, I would love if someone
could point me to a resource that outlines
this, or sell me a copy of the Radiance
book :slight_smile: (that I can't seem to find to
save my life).

Thanks again!

Jeffrey

4

I'm a newbie as well :stuck_out_tongue:

this link has helped me understand the parameters more
http://radsite.lbl.gov/deskrad/param_table.htm

The manpages of rad explains the Quality, variability, detail and other
settings.
though I don't know exactly which setting affect which rpict option

I have notice they change -ar, -ad, -as -ab
Rob Fitz

路路路

-----Original Message-----
From: Jeffrey McGrew
To: [email protected]
Sent: 10/10/2003 10:59 AM
Subject: [Radiance-general] RE: 'Alias' material modifier questions...

First off, that you so very much in your clear
explanation of this. It was a great help!

Now I've got one other question, and then I
promise to leave everyone alone for a while
with my basic ignorance. :slight_smile:

When using RAD to generate Radiance .pic
files, I have experimented with the various
options and understand them on a basic level;
all but the difference between the
'Medium' and the 'High' quality settings.
I know that these change what options
are passed onto rpict, which I'm in the
process of learning more about, however
I'm unable to find documentation that
explicitly lists what options are changed
when one goes from the 'Medium' setting to
the 'high' setting. Seeing that I tend to
get awful artifacts and spotting whenever
I use the 'high' setting, things I feel I
could get rid of if I understood what's getting
passed onto rpict better, I would love if someone
could point me to a resource that outlines
this, or sell me a copy of the Radiance
book :slight_smile: (that I can't seem to find to
save my life).

Thanks again!

Jeffrey

_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general

5

Hi Jeffrey,

I probably posted this advice already a long time ago on this list, anyway, again:

Peter has published an interesting comparison study which -amongst other details - contains a section on (especially ambient) parameter settings which is quite helpful for beginners, its available from his website:

http://www.pab-opto.de/radiance/render_vergleich/report.en.pdf

The Rendering with Radiance book is of course a valuable resource (yeah, this book really exists, I'm
one of the few who has one ..), but the manpages e.g. contain lots of infos, too, about the meaning of
every parameter. Don't be 'afraid' of messing with the parameters, the sooner you leave the overall Quality/Variability etc.. settings and start experimenting with the different parameters directly, the quicker you will gain an understanding of the program.

-Carsten

路路路
6

Rob said:

this link has helped me understand the parameters more
Rendering Parameters: What are they and what do they do

Thank you! this is dead-on for what I was looking for.

The manpages of rad explains the Quality, variability, detail
and other
settings.
though I don't know exactly which setting affect which rpict option
I have notice they change -ar, -ad, -as -ab

right this is the same boat I was in, until everyone's help.

Carsten said:

Peter has published an interesting comparison study which
-amongst other
details - contains a section on (especially ambient)
parameter settings
which is quite helpful for beginners, its available from his website:

http://www.pab-opto.de/radiance/render_vergleich/report.en.pdf

I've read that. I understand the basics of what's going on
within the Radiance rendering engine, and the basic workflow.
I need a better understanding of the rpict perimeters.

Don't be 'afraid' of messing with the parameters, the
sooner you leave the overall Quality/Variability etc.. settings and
start experimenting with the different parameters directly,
the quicker
you will gain an understanding of the program.

This is the point I'm at now; I'm trying to make the
jump from blind RAD settings to understanding RPICT and
being able to feed it what it needs to get the images
I want.

Thanks everyone for making this a lot easier.

Jeffrey