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User-Agent: Mozilla/4.0 (compatible; MSIE 5.01; Windows NT)
Description of problem:
When I use light sources with look_like statement in internal animation
loop (the light source positions depend on time), they disappear (or just
don't illuminate anything, or no_shadow stops working) in all frames
except the first. When I use external animation loop and specify the same
times explicite, the light sources are rendered correctly.
Steps to Reproduce:
1. unpack the attached archive disappearing-light.tar.bz2
2. cd into the created directory disappearing-light
$ povray internal.ini
$ povray external.ini
Actual Results: Two images are created by step 3 (disappearing-
light1.ppm, disappearing-light2.ppm) and one by step 4 (disappearing-
light.ppm), all showing a dark scene with a big red letter G and two shiny
white balls (the only light sources in the scene) whose positions depend
on clock value.
disappearing-light1.ppm is rendered with clock = 0 as first frame in
internal animation loop, the two balls illimunate the G.
disappearing-light2.ppm is rendered with clock = 0.4 as second frame in
internal animation loop, the balls are in different position, otherwise
looking the same, but the letter G is NOT iluminated.
disappearing-light.ppm (this is a reference image) is rendered with
explicitely specified clock = 0.4 showing two balls illimunating the G.
Expected Results: Everything as in actual results, except: The images
disappearing-light2.ppm and disappearing-light.ppm should be identical,
both looking like disappearing-light.ppm.
Created attachment 24927 [details]
scene and initialization files
Small correction: the images are rendered at clock = 0.25, not clock = 0.4.
New observation: povray prints
Scene contains 3 frame level objects; 0 infinite.
when rendering disappearing-light2.ppm (the bad one), while it prints
Scene contains 15 frame level objects; 0 infinite.
when rendering the other (good) images. So the lights seem to `phsically'
Since powertools has been discontinued, there's no future release to fix this in.