LionFish glow in the dark!!!

[James]

I saw this strange effect when foreground light is compltely off....
it happens when the lionfish is turing.....

normaly the lion fish looks like this while turning..


but sometimes it has the glow in the dark effect....
look carefully on the edge of its fins


looks really weird but cool eh?

here are some more examples






I wonder why it's like this.......
any idea Jim?

[Jim Sachs]

It's the order that the polygons get put on the screen. Say a fin gets painted first, then the body. The fin edges get antialiased into the background color, and since the body is farther away, the z-buffer prevents the body pixels from covering the edges of the fins. For the Lionfish, the painting order changes with the angle of the fish. With a fish this floppy, it is difficult to determine at what angle to change the order of polygon rendering. It's a chicken-and-egg kind of thing -- A needs to be after B, which needs to be after C, which needs to be after A.

[James]

thnaks for the lession ...I got more idea about how the order of screen pixel painting now....
so it just like a loop ABCABCABC.....in a ring.....this is the troublesome always appears in programming.....I've experience that b4 as well.....:

sometimes I found that Yellow Tang's tail become black when it's turning.....but the foreground and background light are all completely on......and sometimes Golden Butterflyfish too...
guess it's for the same reason?


btw,I found another strange effect on starfish.....
I turned on the wireframe mode when my starfish in on the glass...a few seconds later....the starfish suddenly "teleport" itself off the glass and start floating down....it all happens in wireframe mode.....then I switch back to normal mode...and the starfish really floating down to the bottom....
then I go check into the control panel.....
the starfish allow on glass is still checked......
I wonder why......