Page 3 of 9

Posted: Fri Feb 06, 2009 12:24 am
by DaddyHoggy
:lol: :lol: :lol: 8)

Posted: Fri Feb 06, 2009 7:15 am
by Thargoid
Captain Hesperus wrote:
Oh dear, seeing the kiddie drawing on it as it floats through space might be a bit hard for me....
S'ok, if it's small wreckage it'll go kaboom after a few seconds...

Posted: Fri Feb 06, 2009 9:13 am
by JensAyton
Griff wrote:
yeah, they are all crinkly like that, you can use a texture map to nibble away at the polygon using the 'discard' command in the shader.
Hmm… you could even have parts of the edges burn away over time. (If time * burniness map * scaling factor > threshold, discard)

Posted: Fri Feb 06, 2009 9:18 am
by Eric Walch
Thargoid wrote:
Captain Hesperus wrote:
Oh dear, seeing the kiddie drawing on it as it floats through space might be a bit hard for me....
S'ok, if it's small wreckage it'll go kaboom after a few seconds...
It's not okay.
The picture on the fridge means that there was a caring father that now died together with its fridge and left an orphaned child behind. Very sad indeed.

Posted: Fri Feb 06, 2009 9:22 am
by JensAyton
Eric Walch wrote:
The picture on the fridge means that there was a caring father parent that now died together with its fridge and left an orphaned child behind.
Let me fix that for you. (Also, that seems a bit optimistic to me.)

Posted: Fri Feb 06, 2009 10:08 am
by Griff
I'll change the picture, it does seem quite sad now in hindsight. It's not a proper kids picture or anything though, i drew it myself!
The idea of an animated map burning away the objects sounds great! sort of like how the vampires vanished in buffy the vampire slayer!
*ponders formula*
Image

Posted: Fri Feb 06, 2009 10:50 am
by Gimi
Griff wrote:
The idea of an animated map burning away the objects sounds great! sort of like how the vampires vanished in buffy the vampire slayer!
Aluminium burns quite violently at very high temperatures when the oxidisation layer is breached, and oxidisation would not occur in space anyway.

Duraluminum could be more heat resistant and glow for a while and then be scoped. Makes a plausible explanation for why some of the metal burns and the other parts only glow.

Posted: Fri Feb 06, 2009 11:07 am
by JensAyton
Gimi wrote:
Aluminium burns quite violently at very high temperatures when the oxidisation layer is breached, and oxidisation would not occur in space anyway.
Yes, but that includes burning. :-) Still, “flaking away due to being bloody hot” strikes me as plausible.

Posted: Fri Feb 06, 2009 11:16 am
by Gimi
Ahruman wrote:
Gimi wrote:
Aluminium burns quite violently at very high temperatures when the oxidisation layer is breached, and oxidisation would not occur in space anyway.
Yes, but that includes burning. :-) Still, “flaking away due to being bloody hot” strikes me as plausible.
Quite right, as that is what would happen in Space with no oxygen.

Posted: Fri Feb 06, 2009 8:19 pm
by Griff
*emerges from shader development lab*
Image
hmm, the effect seems to fizzle out a bit towards the end, i'll have to make sure to paint a clip map that's burnt away most of the object by then so it can be removed from the Ooniverse without it suddenly blinking out of existance, or i suppose if i knew what i was doing, i could just clamp the effect to a suitable maximum value and leave the object floating in space?
here's the relevant bit of the fragment shader *beams with pride*

Code: Select all

// Make the crinkly edge, use effects map Red channel as clipmap 
   float burnawayeffect = clipMap.r * timeElapsedSinceSpawn;  
   if (burnawayeffect > 0.9)  discard; //clip the polygons if the burn effect is over the threshold of 0.9

// Calculate the lighting 
   vec4 color = diffuse * colorMap;
   color += colorMap * specular * 6.0 * specIntensity;

/* Add the glowing metal effect, use the clip map but multiply it a bit so 
it runs ahead of the clip effect giving us a burning edge */ 
   float HeatMask =  clipMap.r * burnaway * 27.0;
   color += MetalGlow(HeatMask) * colorMap;

Posted: Fri Feb 06, 2009 8:27 pm
by Gimi
Griff wrote:
*emerges from shader devekopment lab*
Image
hmm, the effect seems to fizzle out a bit towards the end, i'll have to make sure to paint a clip map that's burnt away most of the object by then so it can be removed from the Ooniverse without it suddenly blinking out of existance, or i suppose if i knew what i was doing, i could just clamp the effect to a suitable maximum value and leave the object floating in space?

I'm looking forward to this.....

Posted: Fri Feb 06, 2009 8:32 pm
by JensAyton
Griff wrote:
hmm, the effect seems to fizzle out a bit towards the end, i'll have to make sure to paint a clip map that's burnt away most of the object by then so it can be removed from the Ooniverse without it suddenly blinking out of existance, or i suppose if i knew what i was doing, i could just clamp the effect to a suitable maximum value and leave the object floating in space?
Yes, I was thinking something like float time = max(uTime, kMaxTime);

There are a lot of built-in functions like that. I use this handy reference sheet to look them up; page numbers there refer to this version of the GLSL specification.

Posted: Fri Feb 06, 2009 10:07 pm
by DaddyHoggy
Griff wrote:
*emerges from shader development lab*
Image
hmm, the effect seems to fizzle out a bit towards the end, i'll have to make sure to paint a clip map that's burnt away most of the object by then so it can be removed from the Ooniverse without it suddenly blinking out of existance, or i suppose if i knew what i was doing, i could just clamp the effect to a suitable maximum value and leave the object floating in space?
here's the relevant bit of the fragment shader *beams with pride*
:shock: Griff, you are a god. Can we expect this effect to appear in Cataclysm Version 2.... :)

Posted: Sat Feb 07, 2009 12:53 am
by Captain Hesperus
Griff wrote:
*emerges from shader development lab*
Image
hmm, the effect seems to fizzle out a bit towards the end, i'll have to make sure to paint a clip map that's burnt away most of the object by then so it can be removed from the Ooniverse without it suddenly blinking out of existance, or i suppose if i knew what i was doing, i could just clamp the effect to a suitable maximum value and leave the object floating in space?
here's the relevant bit of the fragment shader *beams with pride*
That actually seems reasonable. As the metal disintegrates, it'd lose a lot of heat rapidly into the stellar environment so it would have a rapid disintegration, that 'fizzles out' to a slow burn.

Captain Hesperus

Posted: Sat Feb 07, 2009 7:37 am
by Commander McLane
Captain Hesperus wrote:
As the metal disintegrates, it'd lose a lot of heat rapidly into the stellar environment...
I would like to ask that as a question to the people who know more about physics than I do. Would it really? Lose a lot of heat rapidly into what exactly? How would heat dissipate in vacuum? Objects on earth cool because their heat dissipates into the surrounding medium, be it air, water, earth, whatever. But in a vacuum there is by definition no surrounding medium. So my gut tells me that a hot object would not lose a lot of heat rapidly, but stay hot for a long time. Or am I wrong here? :?: