> Hi,
> I'm using values below for higher quality render of a kitchen. I copied them off
> the net somewhere. For normal quality render I skip below code and use regular
> light values of povray. Now what I want to do is put up a slider bar from
> 1 to 5 and change render quality.
> 
> 1- Which value/values below needs to be changed to match the slider?
> 2- Is this the code below right for  higher quality render?
> 
>  global_settings {adc_bailout 0.003922
With reflections and transparence. Can have some effect on the quality. 
Smaller values gives more acurate results, but take longer and may not 
be obvious. You can often use a larger value to get faster renderings 
with no realy dicernable effect on the quality.

>  ambient_light <1.0,1.0,1.0>
NO effect on the quality. Usefull to alter the colour of objects having 
a non-zero ambient finish. Artistic side.

>  assumed_gamma 1.9   hf_gray_16 off
REMOVE assumed_gamma. It is been phased out and will NOT be supported in 
any future version.
hf_gray_16 is user to create a special gray scale image usefull to 
generate hightfields.

>  irid_wavelength <0.247059,0.176471,0.137255>
Not a quality parameter.

>  max_intersections 64   max_trace_level 10
max_intersections is rarely used and normaly don't need to be changed 
from the default value. You can leave out.

max_trace_level dictate how many surfaces you can encounter befor 
stoping and returning black. Importent quality parameter whenever you 
have several reflection and transparences. Works with adc_bailout. Can 
be set to up to 255.

>  number_of_waves 10
Not a quality affecting parameter. Affect the waves and ripples patterns.

>  radiosity {brightness 0.3
Brightness affect the overall brightness of the radiosity scene. Not a 
quality parameter. Lower if the scene is to bright, increase if the 
scene is to dark.

>  count 100 distance_maximum 0.0
count is a very importent quality factor in radiosity. Default to 35. 
Should not be set lower than that. Highest possible value = 1600.

distance_maximum IS NOT a proper key word and is NOT supported by any 
official versions of POV-Ray. It will cause an undefined user variable 
fatal error and abort the parsing of the scene.

>  error_bound 0.4 gray_threshold   0.5
error_bound is another very importent quality parameter. Default to 1.8.
A lower value normaly demands that you increase the count value. Have an 
effect to the "deepness" and sharpness of the shadows.

gray_threshold affect the saturation of the radiosity effects. More 
artistic than quality.

>  low_error_factor 0.8 minimum_reuse    0.015
Both affect the quality.
low_error_factor affect the error_bound during the last pretrace step. 
Usualy, only a slight effect.
minimum_reuse sets the relative distence between radiosity samplse to be 
reused and averaged toghther. Don't set to a value larger than 0.18. 
Smaler value often require a higher count.

 >  pretrace_start 0.08 pretrace_end 0.04
Controls the pretrace passes. can be used to reduce some artefacts. The 
value is a ratio of the horizontal dimention of the image been rendered.
There is no point to set pretrace_end to anything lower than 
2/image_width meaning a last pretrace step of 2x2 pixels tiles.

>  nearest_count    6 recursion_limit  1
nearest_count helps to get smoother results. Maximum value = 20

recirsion_limit set the number of radiosity bounces. Depends on your 
particular scene. Normaly, 1 is good for most exterior scenes, but some 
may need a value of 2 or 3.
Interior scenes ferquently need a value of 2 to 4. If the radiosity 
evvect need to take into acount something behind a pane of glass, and 
you do a single pass rendering, you need at least a value of 3, 2 levels 
been used to get through the pane.

> 
> Thank you very much.
> 
> 
> 



Alain

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