BUT-- i did not have colored circles beside my Materials; my circles are gray and everything stayd gray; no choice of colors shows up;
Hm...you changed the color of the materials to be something other than gray, and then in the Object Mode you looked in the menu where you get "ADD NEW" as an option, and the little circles are still gray? Or are they colored?
However, it turned out to be the Icosphere that ate the universe...
lol! Well, no worries, coloring shouldn't affect size. Just scale the icosphere down to a reasonable size and all should be well.
And Owehn, those trees are to die for! I agree with pappou too; the roots look nice all pointy like that. But if you want to make them more circular, I recommend editing the individual vertices right where the root intersects the ground and shaping them into a rough circle--there's probably an easier way, but I can't think of one at the moment. To reduce shininess, look in the "Shaders" subwindow--it's to the right of the "Material" subwindow (which the three rectangles are located in). Reduce the setting "Spec" to a low value, and your trees should get duller.
Lesson 6
By popular request, today we will be learning about boolean operations.
But first, a bit of review. Rotate around so that you are viewing the cube from a random, off kilter position, and place the 3D cursor somewhere in that view. Create a small icosphere (small enough to fit inside the cube) at this location. Now, using only two "perfect view" commands from the View menu and two translations (use the straight line mouse gesture for this), see if you can position the icosphere in the exact center of the cube. Rotate around to check your work, and then see if you can accomplish the same feat with the 3D cursor, putting it into the center of the cube. Bool, bool, bool
Alright, on to boolean operations! It's easier to show you what these are than to explain abstractly, so let's open up Blender first and try some boolean operations out, and then I'll explain in more detail how they work.
Intersect
We will need two objects, so go ahead and create an icosphere and place it so that it is sticking halfway out of the cube. Now, in object mode, select both the cube and the icosphere. Got that? Okay, then in the 3D view header, choose "Object" and in the menu that opens, select "Boolean Operation..." Select that, and you'll get a little popup window of options with the words "Boolean Tools" at the top. Choose the option "Intersect." Now, I know it looks like nothing happened, but go ahead and move the icosphere and cube out of the way and take a look at what is left!
Yep, whatever parts of the cube and the icosphere were "overlapping" in a 3-dimensional sense have now been made into their own separate object.
Union
Let's try another operation. Place the half icosphere partially inside the top part of the whole icosphere to make a kettle, pot, or vase. Now select both the half icosphere and the whole icosphere and in the "Boolean Tools" popup menu, this time choose "Union." When you move the icosphere and half icosphere out of the way, you'll see that your two objects have been copied and turned into a single object.
Difference
One more operation.
This time, place your whole icosphere into your new vessel (this is the new single object, not the two old separate objects) as though you were trying to shove a basketball into a flower vase--i.e., make sure that some of the rim (which should be nice and even) of your vessel is showing around the edges of the whole icosphere. Use the "a" key to deselect all objects that you currently have selected. (fyi, you can also use the "a" key to select and deselect all objects--give this a try a couple of times. Anyway...) So, got all the objects deselected? Now, FIRST select your whole icosphere, and SECOND select your vessel. Now, in the "Boolean Tools" popup menu, choose "Difference". Move away your vessel and whole icosphere, and what have you got left? A hollowed out vessel. Ah, but what happens when you select the vessel first and the icosphere second, and then do a "Difference"? Check it out and see for yourself... Note that you can tell your most recently selected object by the bright purple outline around it; previously selected objects have a darker purple outline. If you find it hard to remember which object is going to get cut on by which object, just remember: The first-selected object takes a bite out of the second-selected object. So first select the predator, then, its prey.
Some final notes that might be helpful for the modeling practice at the end of the lesson...
1. If you create an object while in Object Mode, you are automatically transferred to Edit Mode. If then you make another object right away in Edit mode, the two objects you created are considered one object. If you try to move them separately in Object Mode, you won't be able to--they're one single object and will move together. If you want your objects to be separate, independent entities, first create one, then go back to Object Mode from Edit Mode, and only then create the other object. Your two objects will then be separate from each other.
2. If a bunch of your objects all turn color when you've only changed the color of one of them, it's most likely because they all share the same material. You'll have to give them different materials if you don't want them all to change color when you change the color of just one of them.
3. Using 2-dimensional objects such as Grids, Planes and Circles in boolean operations can produce interesting results. You might or might not get errors, depending.
Now for some practice...
You don't have to do all of these, by the way.Can you make a gear using a cylinder, a cube, and Union?
Can you make a padlock using a torus, a cube, and Union, and add a keyhole to it using a cylinder, a rectangle, and Difference?
Can you make an orange slice using a cube, a sphere, and Intersect?