Nice to see some progress with your protect!
- can we change the coordinates of the item's spawn on the kart ?
- that seems that my nitro emitter's position change, i haven't check how yet, but maybe you can tell me?
Unfortunately, you can only change the position of the nitro emitter. I think the placement of the other attachments can not be affected manually.
- does STK take care of normalMap today ?
Yes and No. Yes, normal maps are supported in STK, but no, only for tracks and library objects. Someone should correct me if I'm mistaken, but normal maps applied to karts won't render within the current state of the game.
- does the gloss map equals to metallic ?
Not directly. Adding a gloss map to your object just means controlling the specularity and glossiness of the material manually with an image/texture. So you are able to create metallic like material (amonng other things). I will get a little bit more specific further below.
- how do you link AO/gloss if STK can't handle more than one applied UV map ?
As you noticed correctly, STK cannot handle multiple UV maps. So it uses just one and the same for all maps -> texture, gloss map and normal map. That means for you, that when you create gloss or normal maps, you have to be aware of the correct UV coordinates. Thereof results that your gloss maps just differs from your texture by its color. Example:
You can see that the positions of the UV faces has not changed -> the gloss map is equal positioned as the texture. But the color is different:
STK Wiki wrote:
- Red channel: is the specular map. It means how shiny a surface is
- Green channel: is the gloss map. It means how the shininess behave. For instance a wet surface will have a high gloss coefficient, while rubber or latex might be a bit more hazy.
- Blue channel: is the emission map. It means how much the material will emit light. If the light intensity is strong enough it will start to bloom (glow). Important notice: This is only localized and will affect only THE TEXTURE. Not the surrounding area. It's not an equivalent of point light. Usually it's used to force bloom in some particular cases like neons, light bulbs, lanterns, etc.
This is the declaration of gloss maps from the SuperTuxKart Wiki. Let me split it up a little:
The colors of the gloss map defines the material of the textured object. A material can have three parameters: specularity, glossines
. Since every color in a texture is a combination of red, green
, STK just interprets every color channel as the strength of the specific parameter. Example:Black areas
in your gloss map lead to dull material (amount of colors: red = 0, green = 0, blue = 0)Red areas
in your gloss map create a very shiny material. The more deep the red color is, the more brighter your material will reflect.Green areas
in your gloss map will be glossy/plastic like. The more deep the green color is, the more glossier your material will be.Blue areas
in your gloss map will let your texture emit its color. The more deep the blue color is, ... ah you see where this is going.
You can mix colors of course: yellow = red + green amount, purple = blue + red amount, white, orange... whatever you like.Have also a look at this image.How to tell STK to use a gloss map for a texture?
In Blender, you should see the "STK Image Properties" label somewhere in your inspector:
You can there link your gloss / normal maps to your texture. You don't have to open it in Blender nor edit the UVs somehow. Just copy the gloss and normal map you have linked into your kart folder, so STK will find it.
It is good practise to name the gloss and normal map files sensible according your texture filename. Let's say filname.png
is your texture -> I would go with filename_gloss.png
for your gloss map and filename_normal.png
for your normal map.Tips for making gloss maps
You will soon realise that making gloss maps is a pain and incredible time-consuming
. The only way to test your created gloss maps is to test them ingame. Meaning: you have to start STK, view your car on a track, close STK, edit map, save map, start STK, ..... over and over again. There is no preview option for now. Also, the look of gloss map really depends on the lighting conditions of the environment, so consider testing them on different tracks.
What I always do is: move all karts from STK's data to a different location which prevents STK from reloading them on every startup (making it much faster to start). In Photoshop or GIMP or wathever you use, I usually start with the original texture of the object and turn the saturation to zero (making it black / white). Then I fill it with a dark red color (some specularity) as a base for my gloss map. From there I experiment with lighter red colors and green colors (multiplication) until I'm happy with the result in STK.
Just find a way you're comfortable with.
I hope this answer will help you moving on. I'm excited to see with what you come up!