Print view Previous topic | Next topic

Topic Starter	Topic: Quake 3 Alpha Channel textures
Drummah Recruit Joined: 22 Mar 2008 Posts: 2	Posted: 03-22-2008 08:27 AM                  Hi everyone! For a new project, i need the quake 3 textures. I opened the pk3 file with Winzip. The textures were there in JPG and TGA. But i have a problem. For example, the teleport things (known from the space level). They are JPG but not a invisible, but a black background. I can't find any alpha channel anywhere. Does someone know where te alpha channels are? And another problem: The Bouncer things, they have this moving orange/yellow moving circle on it, but where is it? there is only one at one size. Help me please Thanks Drummah.
Top

Foo Timed Out Joined: 02 Aug 2000 Posts: 38064	Posted: 03-22-2008 10:42 AM                    Only the TGAs have alpha channels (and you should find most of the TGAs inside the PK3s have channels since almost every asset that didn't got converted to JPEG to shave space) The JPGs that are used for effects like your description are usually added on using a shader script with some kind of blendfunc/mask where the black shades have no effect on the output while the lighter shades would show up. I'm crap at explaining this...
Top

^misantropia^ Mentor Joined: 12 Mar 2005 Posts: 3958	Posted: 03-22-2008 12:26 PM                  This topic will probably do better in LEM.
Top

Drummah Recruit Joined: 22 Mar 2008 Posts: 2	Posted: 03-22-2008 01:47 PM                  LEM? Thanks for your response, so the TGA's are alpha, and je JPG's aren't. But what about the animated textures? because they really aren't animated at all. I want the bouncer with the moving yellow circle on it, but i guess there is only one frame. please help me again Thanks
Top

obsidian I'm the dude! Joined: 04 Feb 2002 Posts: 12498	Posted: 03-22-2008 05:14 PM                  First thing, you need to study and learn how to write shaders. Shaders are text file scripts that describe how surfaces interact, behave and appear in the game. Two things you want to achieve are to create transparent textures and also to animate them. To achieve transparency, you will need a shader that uses a blendFunc directive. Depending on the type of blendFunc you are using, you may or may not need an alphachannel. The three common blendFuncs are blend, add and filter (there are some more complicated ones as well). Blend requires the use of an alphachannel, it basically reads the channel and applies that to transparency. It is typically used for grates and to layer various textures on top of one another with see-through bits in between. Add is used for glowing effects like fire/explosion sprites, flickering lights and the glowy bits on jump and launch pads. As Foo was "trying" to explain is that additive effects do not require an alphachannel. Lighter shades in the RGB channels are interpreted as being more opaque while darker shades are more transparent. Filter is typically used by the lightmap. So on surfaces that are affected by lighting, you will need a lightmap stage and a blendFunc filter in there somewhere. Very few textures in Q3 actually have multiple cells of animation since it's really not an efficient way to animate things. Usually only fire and explosion sprites use multiple framed animations. Instead, most animated textures have shaders that modulates the texture coordinates to give the appearance of animation. Jump pad yellow circles for instance just takes a single texture frame and scales it up and down to give it a perceived animation. Best way to learn how to use shaders is to check out the default shaders (open with notepad, etc.) that come with Q3 in /baseq3/scripts and also see the shader manual, linked below... http://robotrenegade.com/q3map2/docs/sh ... index.html
Top

seremtan Etile Joined: 19 Nov 2003 Posts: 34900	Posted: 03-25-2008 10:45 AM                  also, if you use any of the vanilla shaders, make sure to use the ones with a white border in the radiant texture browser (is that correct? it's ages since i opened radiant). i'm thinking specifically of the bouncepad textures or the flames etc.
Top

Quake3World.com | Forum Index | Level Editing & Modeling