[Radiance-general] Re: panoramic images [was: applied material ...]

[Greg Ward]

I like Thomas' original suggestion of mapping an image to the window  
and using an illum with the appropriate sky distribution.  If you  
simply use the fisheye.cal mapping I recommended earlier and apply it  
to a fisheye capture out the window, all should be well for any  
perspective view.  However, you will need a fairly high resolution  
fisheye image to make this work.  The description goes something like  
this:

# Define sky
!gensky 5 27 12

# Define high frequency view out window
void colorpict west_view
9 red green blue outsideHF.pic fisheye.cal fish_u fish_v -rz 90
0
0

# Apply view to sky only for West elevation
skyfunc mixfunc full_sky_pat
4 west_view void "if(Dx,0,-Dx^.4)" .
0
0

# Apply this to the sky
full_sky_pat glow sky_glow
0
0
4 1 1 1 0

sky_glow source sky
0
0
4 0 0 1 360

# Define window glazing
void glass window_glass
0
0
3 .92 .92 .92

# Window angle affects transmittance, so use approximation to this
skyfunc brightfunc win_func
2 winxmit winxmit.cal
0
0

# Define the window as an illum minus the exterior pattern
win_func illum window_illum
1 window_glass
0
3 1 1 1

I tried it, and it seems to work OK.

-Greg

> From: Thomas Bleicher <tbleicher at arcor.de>
> Date: May 27, 2008 1:48:40 PM PDT
>
> On 26 May 2008, at 19:11, steve michel wrote:
>
>> It occured to me that since cyl.cal already exist, could mkillum  
>> the sky/ground light distribution be applied to the cylinder of a  
>> panaromic view? That would eliminate having to match the viewpoint  
>> angle with the picture. As you no doubt see, I want to avoid  
>> 'forking' renders and get the accuracy and presentation in one  
>> render.
>
> According to the man page mkillum does not work for cylinders (it  
> works for
> spheres, though, but there is no point in creating a sphere to  
> simulate the
> sky).
>
> Perhaps you could use Radzillas 'ghost' material. IIRC that was a  
> material
> that was visible but did not influence the lighting calculations.  
> If this is true
> you can create a cylinder around your scene without compromising  
> the sky
> distribution.
>
> Regards,
> Thomas