Wow, quite a list. Okay, I'll take a stab at answering as much as I can. The first thing I'd recommend if you're using GIMP is to download the GIMPshop plugin, which will rearrange the menus and options so that GIMP behaves like Photoshop. After that, you'll be able to use almost all the Photoshop tutorials that are out there without having to do any rethinking or translating.
As for the terminology thing, I totally understand how you feel. When I started in digital arts, having come from a traditional art background, a lot of things didn't make sense at first. For now, all I can say is try to stick with tutorials that actually teach, rather than the ones that just give you step by steps with no explanation as to the why's behind them. It seems daunting at first, but you'll be suprised how quickly your brain will adjust to pick up the lingo. I can't reveal any details yet, but I do have a large project currently in the works designed to help people with this exact situation, among other things, but until it's out, scour the web and keep asking lots of questions. There is good information out there, and there are plenty of people right here who are always willing to help.
Okay, let me get to some of your specifics:
From: BlueWillow Kipling
My problem is that I can't put the studs on a normal texture to be applied to each of the prims because the studs would go all over the place. Or I'd have to upload a texture for each prim half a dozen times in trial and error to get the studs to end right where the next prim begins.
Well, actually you wouldn't have to do any of that. By adjusting the repeats per face and the offsets in SL, you can place the studs where you want on each prim by using just one texture. Have each prim display only a part of the texture, and line up the parts so they form a whole.
To manipulte textures on individual sides of prims, make sure the editor window is expanded by clicking on the blue "more" button. The click the "Select Texture" radio button. At that point, you'll be able to select individual prim faces, one at a time by clicking on them, or more than one at a time by shift-clicking them.
Click on the texture tab in the editor window, and you'll see options for how many times a texture should repeat on a selected face, and how it should be offset. It's pretty straight forward what the numbers mean. Let's say you want to spread a single texture across 2 prims so that the appear to be one seamless whole, and let's say they're arranged side by side. Well, forst you'd set the repeats per face to 0.5 instead of 1.0. At this point, they'll both be showing one half of the texture, but the image will be centered on each one instead of aligned between the two. To fix this, just offset the texture by 0.25 horizontally on one prim and by -0.25 on the other.
The reason you need to go with offsets of 0.25 is simple. Before applyint the offsets, the center of the texture is the center of the prim face. You want to move the texture so that it's center is on the edge of the prim in order for it to align with the prim right next to it. The center therefore has to travel across half the face. Since the prim face is currently displaying one half the texture (0.5), the center has to move half of that distance, which is 0.25. I'm sure you figured that out, but you did say to explain it as if to a six year old.
From: BlueWillow Kipling
The solution I've thought of, and I don't know if it's a good one, is to add a rectangular, phantom prim on the side and construct my texture so that it's a picture of the side of the chair as it should be, where it should be, and transparent everywhere else.
That can be a good solution. I build that way often. It's a great way to build complex shapes. You might not want to stop with just the studs though. You could have the whole side of the chair on a transparent background, and then use prims to extrude it. Depending on how the chair is shaped, three-dimensionally, that could work great.
From: BlueWillow Kipling
The first thing I need to know, doing it that way, is how to copy the studs off my scanned in model chair to apply them to my own chair. I'm not good enough to get the studs right building them from scratch.
There are several methods to do this. The first is to simply to erase the parts you don't want with the eraser tool. Alternately, you could select the parts you do want with any of the marquee tools and then either copying and pasting the selection or else inverting the selection to delete everything else.
What I'd recommend though is simply creating your own studs. It's simpler than you think. Here's how to do it quickly in Photoshop. I'm sure there's a similar method for GIMP, but I don't know it.
1. Make a New LayerOn the layers palette, click on the button at the bottom for "make new layer". In Photoshop, it's the one that looks like a square sticker being peeled off its backing. I haven't played around with GIMP in well over a year, so I'm not sure what the button might look like there, but it's gotta be there.
2. Make a Circle Click on the eliptical marquee tool to use it. Draw a circular selection on the canvas by clicking and dragging the mouse diagonally. Hold shift while drawing to keep it uniform so that it's a circle and not an elipse. When you've got a good large circle, let go of the mouse. You'll see a flickering line, known in graphics lingo as "marching ants", in the shape of a circle, indicating that a selection has been made.
3. Fill the CircleUse the paint bucket to fill the circle with a solid yellowish color, similar to brass. Click on the Select menu at the top of the screen and then click "Deselect" to kill the marching ants.
4. Use Blending Options for Depth and ColorThe instructions in this step are very Photoshop specific. I know this will translate to GIMP, but I don't know exactly how, since I haven't played with GIMP in a long time.
In the Layers Palette, right click on the name of the layer with your circle on it and then click on "Blending Options". A dialog will open with a lot of options for applying special effects to the layer. Make sure the checkbox for "Preview" is checked so you can see what happens to the image in real time. Click on the words "Bevel & Emboss". You'll see that clicking on the name of an effect opens up the options for it and turns the effect on.
You should now be looking at the settings for Bevel & Emboss. You'll notice that the window is sectioned into two main headings, Structure and Shading. In the Structure box, set the Style to Inner Bevel, the Technique to "Smooth", and the Direction to Up. For Size, watch what happens to the image as you drag the slider back and forth (make sure the dialog window is moved so it's not covering your circle; you want to see what's happening). You'll see that as you move the slider to the right, the shading changes on the circle. at low settings, the circle is shaded kind of like a button you might find on a leather jacket, flat in the middle and curved around the edges. As the Size setting increases, the flat area will get smaller and smaller. When the setting is about half the width of the circle (in pixels), the shading will make the circle appear spherical. That's the setting you want.
In the Shading box, make sure "Use Global Light" is checked. This will make sure that whatever changes you make to the light source for this layer will affect all layers. This is very useful for making sure that the whole image appears to be lit from the same direction. It's not entirly necessary for just this simple yellow sphere, but it's good practice. You can set the light angle and altitude to whatever you want, depending on the eddect you're going for, but I find 90,30 is usually a good neutral setting for viewing from all angles in SL. For Gloss Contour, you can play with the presets to see what they do, but I'd recommend leaving it at the default setting. Make sure Anti-Aliased is checked to avoid any jaggies along the diagonal edges.
Now for the finesse, the Highlight and Shadow settings. By default, Highlight Mode should be set to Screen, and Shadow Mode should be set to Multiply and the Opacity for both is 75%. Leave them that way. Next to Highlight Mode, you'll see a white square, indicating that the color of the highlight is white. Leave it that way. Next to Shadow Mode you'll see a black square. Click on it to bring up the color picker. This is how we're going to transform our shpere from yellow to brass. You see, shadows on brass are not black; they are orangy brown. Pick an orange color. You'll see your yellow circle now looks like a gold sphere.
Gold's not what we want though, we want brass. So, as a finishing touch, click on the words "Gradient Overlay" in the Blending Options column. You should now see Gradient settings for the layer. Make sure Blend Mode is set to Normal (I realize I've gone twice now without explaining what the modes are, but that's a whole chapeter in and of itself. Stay tuned for more info on that, but it's way beyond the scope of this tutorial.) and the opacity is set to 100%. By default, the gradient will be black to white. That's not what we want at all. We want yellow to brown, the colors of brass. Click on the shaded box next to the word Gradient to bring up the Gradient Editor. Leave all the settings as they are, but change the colors. About 3/4 of the way down the Gradient Editor window, you'll see a shaded horizontl strip, illustrating what the gradient currently looks like. At the 4 corners, you'll see 4 little boxes, called stops. The top ones are for opacity. Leave those alone. The bottom ones are for color, and those are the ones we want to change. Click on the black one to select it. You'll see the box that says "Color" at the bottom of the window change to black. Click on the box to bring up the color picker and change it to a nice light yellow. Now click on the white color stop and change the setting to a dull greenish brown. Click OK to acceopt the color change. This will close the Gradient Editor so you can go back to the previous window. Set the Style to Radial. This will cause the gradient to start in the middle of the circle instead of at the side. Make sure "Align with Layer" is checked. The circle should now look very much like a spherical brass stud. If it's too dim, increase the Scale on the gradient a bit so there is more yellow and less green-brown. When you're satisfied, click OK.
Now you've got one brass stud. You can either use it as a stand alone texture and just repeat it a bunch of times in SL, or you can copy it a bunch of times in Photoshop or GIMP and lay the copies out in whatever pattern you like.
From: BlueWillow Kipling
The problem I'm having is there's this black checked liney thing, like coarse burlap, over the scanned chair and I'm too new to GIMP to understand why.
Sounds like you're seeing the grain of the paper in your scan. Try scanning at lower resolution. For screen images, 72 DPI is all you need. If the image is too small for 72 DPI to work, meaning it needs to be blown up, then you're gonna have to use some artistry to get rid of the grain. I could write a whole chapeter about how to do that. For now, I'll say learn about blur options, painting, healing, and clone stamping. I realize that's vague, but you're kind of asking for an entire semester's worth of digital art instruction in one post. I've got something in the works for that sort of thing, but I can't put it right here right now.
From: BlueWillow Kipling
I'm going to need to know how to manipulate the size of the studs to make them right as I apply them (preferably in small strips so the stud to stud spacing is uniform).
Manipuations to size, rotation, skew, etc., are called "transforms". Changing size specifically is called "transforming scale" or "scaling". In Photoshop, you'd go Edit -> Transform -> Scale. I don't know what the command sequnce is in GIMP, but it's gotta be similar.
If you're going to scale the stud we made in the aboce exercise, make sure you change the Bevel & Emboss size as well. Remember, it only looked spherical when we set the size to half the width of the circle. If you change the size of the circle, you're gonna need to change the size of the bevel proportionally. An alternative is to bake in the effects by creating a new empty layer underneath the circle and then merging the two (Layer -> Merge Down), but I'd recommend against that. It will save you a few seconds time upfront, but it will limit your flexibility later.
To make strips of studs, first select the Move Tool. In Photoshop, holding alt and dragging the mouse will produce a copy, similar the the way shift-dragging in SL will copy an object. (I'm sure there's a similar hot command in GIMP, but again, I don't know what it is.) Just alt-drag out new studs one at a time, and then place them where you want them. Each one will spawn neatly on its own layer, so it will be really easy to move them around individually later on if you need.
From: BlueWillow Kipling
One of the things I need to know to do my shading and highlights is how to get the color the same as my chair just with the slider bar that adds more black or more white to change shades. The highlights and shadows where light isn't gleaming off the leather appear to be variants of the underlying color. The highlights where it shows that the leather is glossy and light is gleaming off it look like they're white.
I'm not following you here. To what slider bar are you referring? Please explain.
You are correct that highlights and shadows are not black and white. Until you get to the very extremes, highlights and shadows are ALWAYS brighter or deeper shades of the base color they affect. If your chair is brown, then the shadows should be deep brown. The highlights should be light brown. The most intense highlights on a glossy surface will be white, but only the most intense ones. The most intense shadows on all surfaces are black, but again, only the most intense ones.
From: BlueWillow Kipling
I also desperately need an explanation-for-dummies on background and foreground colors and how they work and what they mean and how they impact what happens when I use a tool.
For most tools, the background color is meaningless. It's only for cetain things like rendering clouds, noise, fibers, etc. that the foreground and background colors ever interact. In most cases, only the foreground color is active. I usually use the background color as kind of a reserve. For simplicity, let's say I'm painting a blue sign with hand-written yellow lettering. I'd keep the 2 colors I'm using stored in background and foreground. I'd put the blue on the foreground to paint bucket the canvas blue, and then I'd switch the foreground and background colors to bring up the yellow to paint brush my lettering. If I make a mistake, I can switch again to paint blue over the yellow mistakes. That's a really over-simplified explanation, but I think you get the idea.
From: BlueWillow Kipling
I need to understand how to make sure a given layer is transparent except for the non-white pixels I'm putting on it--and how to make sure the white pixels of my glossy highlights are white and not transparent.
Layers are always transparent until you start painting on them. They remain transparent in all unpainted areas. If you paint white, it will come out white.
It sounds like what you're really asking is how to use values of black and white to create transparency in alpha channels. This has nothing to do whatsoever with what you paint into layers. The confusion between layers and channels is rampant on this board because for some reason I can't fathom, this is the one place on the whole of the internet where people insist on using the two words iterchangeably, even though they have absolutely nothing whatsoever to do with eachother. Please see
this thread for a detailed explanation of what they both are.
Also, here's my standard 10-Step tutorial for creating transparency with Alpha channels, which you'll find all over this board, since transparency is the number one most asked question on the forums, and I answer it the same way every time. Again, the instructions are Photoshop specific, but the concepts apply to all professional grade graphical editors. My girlfriend was able to follow it and she had never before used Photoshop in her life (her computer skills consist of MS Word and Internet Explorer) so I know it's foolproof. That having been said, if you can't follow any of it, come back & ask.
Color Space & ChannelsImages designed to be shown on a color screen are comprised three colors (red, green, & blue). The relative brightness of each of these primary colors in each pixel determines each pixel's actual color. For example, a pixel comprised of equal values of red and blue without any green would appear to be purple.
When taken seperately, the individual values for red, green, or blue are represented by a grayscale image called a channel. In an individual channel, white represents the maximum possible concentration of color and black represents the absense of color. Shades of gray represent amounts of color that are less than the maximum. The darker the gray, the lesser the concentration of color. The lighter the gray, the more color is present. So, to go back to the example of combining red and blue values to make a splotch of purple, the splotch would appear white in the Red Channel, white in the Blue Channel, and black in the Green Channel, the reason being that the splotch contains the maximum possible values of red and blue, but no green.
Channels & Transparency (Alpha Channels)Images that have transparency have the same three primary color channels and also have a fourth channel, called Alpha, which represents opacity. In the alpha channel, white represents comlete opacity and black represents the absense of opacity (transparency). Shades of gray represent semi-transparency. The darker the gray, the more transparent. The lighter the gray, the more opaque.
So, for example, if you are making a bikini top for your avatar, the alpha channel would be white in the shape of the bikini top, and black everywhere else. The white part makes the bikini top 100% opaque so that you won't be able to see through it when it's on the av, and the black part makes the rest of the image invisible so that there appears to be nothing on the av's arms, stomach, etc.
How to Create an Alpha ChannelLet's stick with the example of a bikini top.
1. On the Layers Palette turn off all layers except for the layer that has your bikini on it. (To turn a layer off, click the eyeball symbol to the left of its name.)
2. If the bikini layer has any white space around the bikini itself, use the eraser to get rid of the white space. It's very important at this stage that the bikini be on its own layer with nothing else on it.
3. On the Layers Palette, ctrl-click the icon for the layer with the bikini on it. (The icon is the little picture of the layer directly to the left of the layer's name.) This will select everything on the layer. You should see the "marching ants" outlining your bikini now.
4. On the Layers Palette, click the tab that says Channels to switch it to the Channels Palette. What you should see listed here are the three primary channels for your image, labled, "Red", "Green", & "Blue", and a master channel for the three, labelled "RGB". If you see any other channels besides those four, delete them now.
5. In the lower right corner of the Palette Window, locate the button that looks like a square sticker being peeled from its backing. It's the second one from the right. It's immediately to the left of the one that looks like a trash can. It says "New Channel" when you hover your mouse over it. Click it.
6. You should now see a new layer called "Alpha 1", which is currently all black. Make sure all channels except for Alpha 1 are turned off and that Alpha 1 is turned on. This should have happened automatically when you created Alpha 1, but if it didn't, do it now.
7. Your canvas should now appear to be solid black with the exception that you should still be able to see the "marching ants" outline of your bikini. Paint everything inside the outline white and leave everything outside of it black.
8. Click "Select" on the menu bar at the top of the screen to pull down the Select Menu. Click "Deselect" and you should see the marching ants disappear.
9. On the Channels Palette, trun the red, green, & blue channels back on, and turn Alpha 1 off. Now click the tab that says layers to switch back to the Layers Palette. Create a new layer by pressing the same button you previously used to create the new channel. (Just as it created a new channel while you were on the Channels Palette, it will create a new layer while you're on the Layers Palette.) Click on the name of this new layer and drag it underneath the layer with the bikini on it. Paint the new layer 50% gray or darker; black is fine. (The gray/black layer will prevent the white halo sometimes caused when Alphas are created the way we just did it. If you don't know what I mean by that, don't worry about. Just make sure to always put a gray/black layer underneath your work and you'll never have to see that white halo.)
10. Save your file as a 32-bit TGA and upload it to SL.
From: BlueWillow Kipling
It would be nice if I understood some way to tell the GIMP that my chair side is a single "thing" instead of a mass of pixels of various shades of red-brown, undifferentiated from the surrounding mass of pixels that are hopefully transparent but maybe just white.
And it would be nice if my toaster were able to know that it's actually for making toast, and not just for heating up its coils for a specified amount of time and then shutting off, but that ain't gonna happen. Machines are dumb. They only know function. Interpreting that fuinction as meaningful form is up to us.
The best you can do if you want the program to recognize an image element as an object is to put it on its own layer.
From: BlueWillow Kipling
I also need to understand, if I have a transparent layer to do shading or highlights, how the pixels I do on that layer interact with lower layers. When I at the end (after saving my individual layers) merge it all together, do my non-transparent pixels I paint in on the top layer completely replace the corresponding ones on the bottom layer, or is there some additive function I need to be aware of?
When merging, what you see before the merger is exactly what you'll get after the merger. It gets a little more complicated if there are layer blending options in effect, but assuming the bottom layer in the merger has no effects, then WYSIWYG holds true.
That having been said, it sounds like you're falling into the trap of thinking you have to flatten your image before saving. Don't ever do that. You want to keep your layers intact for later in case you ever have need to edit. When you save as TGA before upload to SL, the TGA will save out as a copy, and your layered master document will remain intact. TGA is an inherently flat format, so pre-flattening is completely unnecessary. I have no idea how that step began floating around this board as the thing to do, but I can assure you it serves no purpose.
From: BlueWillow Kipling
One of the reasons I ask that last is that I noticed in erasing the non-chair stuff from around the chair, at 800% magnification, that the eraser would often make pixels at the edge just lighter instead of gone and I'd have to click it several times to actually make the unwanted pixel go away. What I'm worried about is, if I missed some am I going to have some nearly-white pixels at the edges of my chair forming a white fog around the edges? Maybe with just a stray pixel it won't matter, but I'd like to know before I upload.
Good observation. The lightned pixels you're noticing are due to what's called "anti-aliasing", the process by which computers combine colors to minimize the appearance of jagged edges. When using multiple layers, what happens as you erase is that the pixels along the edge of the eraser become semi-transparent so they can combine their color with the color of the corresponding pixels on the layer below. If you're erasing above a white background, the pixels will appear to lighten. If you're erasing above a dark background, they'll appear to darken. Their color hasn't really changed though, just their opacity. If you change the color of the layer below a couple times and watch those pixels, you'll see.
You'll notice a great many images with transparency in SL are plagued with white halos around image elements. Follow the tutorial I just gave you, and you'll never have that problem. Whatever you do, don't ever use one of those auto-alpha tools like the one mentioned that "End Your Alpha Channel Woes" thread on this board. If you do, it'll be white halo city for you for all eternity. I keep hoping that thread will die, but it keeps getting revived every so often.
From: BlueWillow Kipling
How many times do you usually have to upload a texture on an item to get it right?
Depends how experienced you are. Not to toot my own horn, but it's pretty rare these days that I ever have to do more than one upload to get things the way I want them. As you get better and better at what you're doing, you'll develop an intuition for how to "see" in 3D as you're painting in 2D. That's something that can't be taught. It can only come with practice.
From: BlueWillow Kipling
Any tips on aligning the textured phantom prim to the chair?
Place the phantom prim first, and build the rest of the chair right on top of it. In other words, use it as a construction template.
From: BlueWillow Kipling
Anything else you think I should know? Tips? Pitfalls? Confusing terms?
Plenty. You're learning the equivilent of a new language here. Ask as many questions as you can. Sorry, I don't have any specific answers to this question right now, but I think it's better to baby step it. I just gave you a ton. If you don't understand anything I've said so far, please come back and ask. Once you have a mastery of what we've talked about so far, you'll have new questions you never would have thought of before.
From: BlueWillow Kipling
BTW--I hope you can tell, I'm not looking for a quick buck. I've always wanted to make stuff like this but have been daunted by the costs of materials and tools (okay, so I'm cheap). But if you already use a computer for a living, pixels are cheap.
So I'm kind of fulfilling a lifelong fantasy of making neat stuff for sale. I have an artistic temperament (I'm an author) but I'm also new to the visual arts.
Hey, quick buck or no quick buck, fulfilling fantasies is exactly what SL is for. And there's never any reason to feel guilty for making a healthy profit, so don't eve apologize when you do.
From: BlueWillow Kipling
Forgive me for copying someone's existing furniture pieces, but I have to have a starting point to learn how to use the tools, how to do the shading and highlights, how the prims combine to make more complicated shapes, etc.
I'm glad your conscientious, but I wouldn't worry about it. There are certain things you definitely shouldn't knock off, but I don't believe furniture is one of them. Even in the real life furniture business, there's almost no originality. A die hard enthusiast might disagree, but generally speaking, everything looks like everything else. Pick any style chair, and you'll find a hundred manufacturers who make their own version. You're just one more.
Besides, from a practical sense, what could you possibly be infringing upon? A chair is not a character, not a logo, not a book. You can't trademark it, can't copyright it. One could certainly patent any novel elements of the construction or the function, but there's no way you'd ever replicate any of that in SL, so there's no danger of patent infringement. All you can do in SL, really, is slap a few imaginary boxes together and paint them to look meaningful. The debate about whether it's really even a chair could go back and forth until the stars burn out. It's certainly a representation of one, but so's a painting, and no one would ever get mad at you for painting someone sitting in a certain chair over some other chair.
Anyway, I hope this was helpful.
