Request: Someone do a tutorial on Light faces in gameblender

Ok I know this is a big request. But after four years and reading that “Getting rid of the pink” tutorial at least 20 times. AND after reading the vertex paint,Materials,UV texture, and Face button sections of the 2.0 Guide,the blender game kit and the 2.3 guide AT LEAST 50 times this whole concept still confuses me.

I understand where that you need to UV texture a model to make it look really good in the game engine. I understand that you need to press ALT-Z in order to have that texture show up in the 3d window or before you press P to start a game.

I THINK that i understand how vertex painting works ALTHOUGH the ADD,SUB,MULTIPLY,MIX and FILTER buttons still confuse me. I normally just leave the buttons as they are when I start up blender because I really do not understand what they do. YES I have read the explanations dozens of time.

I will not even go into my confusion about the face buttons. I think I understand most of them except the OPAQUE,ADD,ALPHA,LIGHT and SHADOW. Let me say once again YES I have read the manuals,dozens of times but the explanations just do not make sense.

well, those are for vertex painting

they act like the blending modes in photoshop

add makes things brighter
sub makes them darker
multiply does as well, but differently [more noticable with different colors]
mix will blend the two colors
and filter… I forget

those are face flags

so, the three at the bottom (opaque, add, alpha) determine the blending mode.
so, opaque faces are opaque, alpha faces are alpha blended [so, you can have holes if your image has an alpha channel, or you can see somewhat through it…], and add faces are added to the existing color [it kinda looks like a ghost face… it makes everything behind it brighter]

the other buttons are flags for the face, and some are [or should be] mutually exclusive. Tex for example needs to be pressed to have a texture on the face, if it isn’t pressed Text doesn’t make much sense [why would a box make a good font]

shadow faces are the faces in an object which are treated as a shadow, this should be another tutorial on its own [I doubt I will get to this later]

Tiles isn’t very useful, but iirc it is required for animated textures

Light is pretty obvious

Invisible is pretty obvious

Halo and Billboard faces try to face the camera. Billboard faces will only rotate around the z axis to do it, so they will not necescarily be facing the camera directly. These are best used when the object has only one face [a quad], and last I checked they use the negative X axis as the direction that face should point

well anway, if you want me to ramble about static lighting my way, I’ll do it in 3 images
an environment as seen in control+z (shaded) mode [more-or-less]. Lighting created with spot lamps and sphere lamps, which will not be in a visible layer when the game is run
to make those colors vertex colors:
result [has textures…]

this method does not work with light sensitive faces well, vertex colors define the brightest color that vertex can be if it is dynamicly lit [the face it is in has the light button pressed in the face buttons]

Geez man, RTFM :wink: Ok, I’ll take a stab at this-

Blending modes (Add, Sub, Mult, etc) - These planes were vertex painted with Red, Green, and Blue circles (in that order) with the various blending modes.

Add - The RGB values are ADDED together, so when you paint Red (RGB 1,0,0) and then Green (RGB 0,1,0) , you get Yellow (RGB 1,1,0)

Mix - The RGB values get OVERWRITTEN, so when you paint Red (RGB 1,0,0) and then Green (RGB 0,1,0) , the Green will overtake the red and eventually you will end up with just Green (RGB 0,1,0) Notice how the circles overlap instead of blend together.

Subtract - The RGB values get SUBTRACTED, so if you start off with White (RGB 1,1,1) and then paint Red (RGB 1,0,0), you’ll end up with that blinding shade of Blue we call Cyan (RGB 0,1,1) This blend mode is kinda like painting with watercolors.

Multiply - The RGB values get MULTIPLIED, so if you start off with White (RGB 1,1,1) and then paint Red (RGB 1,0,0), you’ll just end up with Red (RGB, 1, 0, 0) since the Red channel was multiplied by 1, and the Green and Blue channels were multiplied by zero.

Now say you painted Green (RGB 0,1,0) on top of this Red (1,0,0), you’ll actually end up with Black (0,0,0) since the Red channel (the only one remaining at this point) gets multiplied by zero.

Fliter - This one’s kind of the oddball… not very useful and better left untouched :slight_smile:

About the Face Buttons,

Opaque - Makes your faces opaque (non-transparent). The vast majority of your polygons will be set like this since most of our environment isn’t transparent :).

Add - Just like the blending mode for vertex paint, Add mode adds the color of the polygon to whatever’s behind it. Used anywhere you need a brightening effect, like fire, explosions or neon lights.

Alpha - Makes the polygon transparent. The transparency will depend on your texture’s alpha channel (look in your image editor’s help for information on how to make one) or the polygon’s material. This mode is commonly used for smoke and water.

Light - Shades the polygon based on the lights in your scene. It will only respond to lights on the same layer and only up to a maximum of 8 lights. This is used whenever your object will be moving, like for your characters and props. Don’t use it for your environment however- vertex painting is generally better for that.

Shadow - Puts the polygon flat on the floor to simulate a shadow. Say you were making a Mario type game- you’d add a black circle (and move the points upward slightly because you’ll want to seperate it from the ground) and parent it to your character model. Set the faces on the circle to shadow, and now whenever your character jumps, the shadow will stay behind on the ground.

Best way to really understand all of this is to experiment. Good luck!

Oh! Thank’s Guys. :smiley: This is a good Explanation.

Thanks z3R0 d and dmao those explanations were much more clear then in the books that I read. Thank especially dmao for the pictures those helped a lot. As they say a picture is wroth a thousand words.

I am still confused by all of this but these post makes the fog a bit clearer.