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DanUR
03-01-2005, 10:31 AM
Hello. I have created an object with a glow, then cloned it many times to recede into the distance.

My problem is that the glow does not scale proportionally with distance, the way that the geometry does.

I've searched the forums but found no threads on the subject. I assume I'm overlooking something obvious.

Any advice is appreciated.

Thanks

spec24
03-01-2005, 11:35 AM
there is an envelop button next to the glow effect in the surface panel. Use this to make the glow change with distance.

DanUR
03-01-2005, 11:44 AM
I am quite embarrassed for not thinking of that.

spec24
03-01-2005, 12:04 PM
no need :)

rikardlassenius
03-03-2005, 03:02 PM
didn't quite follow...
how do i use the envelope to do that?
basic stuff, huh?
:confused:

DanUR
03-03-2005, 03:20 PM
I replied before I tried it. I misunderstood, and thought the Texture editor would be available, and I could use "distance from camera" or some such gradient parameter. But apparently all you can adjust is the envelope.

I've attached a JPEG of the issue I'm having... a two point poly 100m along the Z, one point in the foreground and the other point quite distant. It's got a heavy glow assigned to it. I want it to appear to recede into the distance, but the glow does not scale or diminish.

It doesn't seem like an envelope would solve this.

toby
03-03-2005, 03:26 PM
I'd try a 'distance to camera' gradient in the luminosity channel. Also, the Corona post-process filter has more options than the standard glow.

toby
03-03-2005, 03:48 PM
I replied before I tried it. I misunderstood, and thought the Texture editor would be available, and I could use "distance from camera" or some such gradient parameter. But apparently all you can adjust is the envelope.

I've attached a JPEG of the issue I'm having... a two point poly 100m along the Z, one point in the foreground and the other point quite distant. It's got a heavy glow assigned to it. I want it to appear to recede into the distance, but the glow does not scale or diminish.

It doesn't seem like an envelope would solve this.

You might have trouble with a 2 point polygon because it doesn't get skinnier with distance.... you might get it to work by using the 'edges' panel under properties, it has some distance parameters, or make an object with some thickness

spec24
03-04-2005, 08:29 AM
if you use the envelop to adjust the glow intensity then it will work. You can either do this manually or by linking the channel to the objects distance from the camera using expressions.

DanUR
03-04-2005, 11:16 AM
I thought I understood envelopes, but maybe I don't. I thought envelopes only effect changes over time, and don't really serve a purpose in building a still image.

I did, however, get fairly good results with Toby's suggestion of using the 'distance to camera' gradient in the luminosity channel. So thanks Toby... good call.

spec24
03-04-2005, 07:44 PM
I thought I understood envelopes, but maybe I don't. I thought envelopes only effect changes over time, and don't really serve a purpose in building a still image.

I did, however, get fairly good results with Toby's suggestion of using the 'distance to camera' gradient in the luminosity channel. So thanks Toby... good call.

My apologies DanUR - I thought you were trying to make an objects glow lessen in an animation. :D

mgrusin
03-06-2005, 10:00 AM
If I understand what you're after, glow may not really be what you want. AFAIK, glow is a post process effect; it takes anything bright in your finished image and spreads it out a certain number of pixels. It doesn't care about how far away the object is.

I'd consider not using glow but adding extra geometry to your object, and surfacing the extra geometry to appear glowing (edge transparency may help here). This should fade out with distance the way you want.

Hope this helps, -MG.

toby
03-08-2005, 02:42 PM
Actually, even in real life, glow depends more on intensity, camera lens and film than distance - glow never exists on the object you see it on, it's only in your eye or on the film - so you should be able to get good results with a post-process.