It's great that we can do all sorts of glowy effects using particles, light beams using transparent prims, etc. The problem is that the effects don't appear very realistic, because the only alpha blending mode that SL supports is weighted averaging: a pixel on an alpha texture is either opaque, transparent, or somewhere inbetween (see blend1.jpg for a messy example). While this method is great for many purposes, light effects is definitely not one of them. Light effects are not supposed to be opaque, nor should they be able to darken what's behind them.
Additive blending, on the other hand, makes for more realistic light effects by combining the brightnesses of the alpha texture and whatever is behind it (see blend2.jpg). This automatically ensures that the light effect cannot darken or be opaque.
I'd really, really like to see an option for setting prims and particles to additive blend. Practically every modern game out there uses this for light effects -- why not SL?
Welcome to the Second Life Forums Archive
These forums are CLOSED. Please visit the new forums HERE
Additive blend mode for alpha textures ("real" glow effects) |
|
|
Beatfox Xevious
is THOUSANDS OF PEOPLE
Join date: 1 Jun 2004
Posts: 879
|
09-25-2005 23:27
_____________________
My Beatworks: Zephyr Chimes wind chimes, the KanaMaster Japanese kana tutor, and the FREE Invisibility Prim Public. Look for them at the Luskwood General Store in Lusk (144, 165).
"You have been frozen. You cannot move or chat. A pony will contact you via instant message (IM)." - mysterious system message I received after making off with Pony Linden |
|
Strife Onizuka
Moonchild
Join date: 3 Mar 2004
Posts: 5,887
|
09-26-2005 12:46
That could be interesting.
[stamp of approval] _____________________
Truth is a river that is always splitting up into arms that reunite. Islanded between the arms, the inhabitants argue for a lifetime as to which is the main river. - Cyril Connolly Without the political will to find common ground, the continual friction of tactic and counter tactic, only creates suspicion and hatred and vengeance, and perpetuates the cycle of violence. - James Nachtwey |
|
Zodiakos Absolute
With a a dash of lemon.
Join date: 6 Jun 2005
Posts: 282
|
09-26-2005 17:13
Could also add subtractive blending too... all sorts of fake volumetric lighting effects could be possible with both of those blending methods.
|
|
Beatfox Xevious
is THOUSANDS OF PEOPLE
Join date: 1 Jun 2004
Posts: 879
|
09-29-2005 15:33
I've added a proposal for those who'd like to see this implemented:
Prop 631 - Additive blending for improved light/glow effects _____________________
My Beatworks: Zephyr Chimes wind chimes, the KanaMaster Japanese kana tutor, and the FREE Invisibility Prim Public. Look for them at the Luskwood General Store in Lusk (144, 165).
"You have been frozen. You cannot move or chat. A pony will contact you via instant message (IM)." - mysterious system message I received after making off with Pony Linden |
|
RichardEric Collins
Registered User
Join date: 29 Aug 2007
Posts: 16
|
09-05-2007 07:28
I've just given this 10 votes, its a must!!! I was working on games 15 years ago with software renderers that had additive alpha!!! Its really a poor show.
All the need is a type used in the llSetPrimitiveParams to set the alpha type. Just fallback to normal alpha on systems that can't do it, although the last card I saw that could not do modulate or subtractive was a NVidia TNT2!!! (last card before GForce) llSetPrimitiveParam([PRIM_ALPHAMODE,ALPHA_NORMAL]); (src * src alpha) + (dest * inv_source_alpha) llSetPrimitiveParam([PRIM_ALPHAMODE,ALPHA_ADDITIVE]); (src * src alpha) + (dest * one) llSetPrimitiveParam([PRIM_ALPHAMODE,ALPHA_MODULATE]); (src * dest) + (dest * zero) llSetPrimitiveParam([PRIM_ALPHAMODE,ALPHA_SUBTRACT]); (src * one) - (dest * one) //This can be kind of cool for reflective mapping. Give us this and WOW, it will look amazing! |
|
Haravikk Mistral
Registered User
Join date: 8 Oct 2005
Posts: 2,482
|
09-05-2007 13:22
Is there a corresponding JIRA proposals? I spent a while playing with shaders for Quake 3 (Jedi Knight 2 actually but it's a Q3 game) and they are just incredible the effects you can pull off just by mixing two images or playing with alpha blending.
Layered textures obviously isn't quite as likely for SL, due to having to load them, but I'd be all for different modes for applying alpha channels. They're really easy to do in OpenGL as well and complement Windlight pretty damned nicely. _____________________
Computer (Mac Pro):
2 x Quad Core 3.2ghz Xeon 10gb DDR2 800mhz FB-DIMMS 4 x 750gb, 32mb cache hard-drives (RAID-0/striped) NVidia GeForce 8800GT (512mb) |
|
Draco18s Majestic
Registered User
Join date: 19 Sep 2005
Posts: 2,744
|
09-06-2007 06:47
I've just given this 10 votes, its a must!!! I was working on games 15 years ago with software renderers that had additive alpha!!! Its really a poor show. You know that the Vote system is beyond dead, right? |
|
Jopsy Pendragon
Perpetual Outsider
Join date: 15 Jan 2004
Posts: 1,906
|
09-08-2007 11:57
Also
Check out Client -> Debug Settings -> RenderGlow: TRUE While it isn't something you can enable for your guests for them... it does allow for some very atmospheric snapshotography. There are 3 other RenderGlow settings you can tinker with to tune the effect. _____________________
* The Particle Laboratory * - One of SecondLife's Oldest Learning Resources.
Free particle, control and targetting scripts. Numerous in-depth visual demonstrations, and multiple sandbox areas. - Stop by and try out Jopsy's new "Porgan 1800" an advanced steampunk styled 'particle organ' and the new particle texture store! |
|
Day Oh
Registered User
Join date: 3 Feb 2007
Posts: 1,257
|
09-08-2007 12:12
Link to JIRA feature request, please XD
_____________________
 |