Blender 3D: Noob to Pro/Using an empty object for coordinates of the textures
So, you've read the tutorials on how to model, or you've used Blender before... Cool. Now what? You've created a nice model, you know how to animate it, but you want your textures in a way that Blender won't let you use by default.
Well, don't despair. Blender's not out of resources for you just yet.
I'll take a simple model, and I'll assume you know how to set the camera, render settings to default and add an object.
I'm going to create a simple representation of our planet Earth. Images for that can be found on the web, and there's a finished blender file ready linked at the bottom of this tutorial which has the textures packed in it.
First you get rid of the cube from the default scene. Keep the light and the camera as is. Next add a sphere, go back to object mode and add an empty from the add menu (screenshot below).
Once you added it, you want to add a material to the sphere. Look at another page on how to do that. Once you have the material added, add a texture to the material. Once added, select the type, image.
Load the image (in this case the image is packed within the example blender file) as the texture. Use whatever options you want for the image to appear correct in the preview window.
Once the texture applies to the material, go back to the materials tab (red sphere). There, look for the Map Input tab, and open it. Select Object, and enter the name of the empty object. In this case it will be "Empty" (it is case sensitive, so watch out).
Now try and animate a rotation on the empty, say 360 degrees in 360 frames. (See another tutorial to learn how to do that). Don't move the sphere, and render the animation.
TADA! The earth seems to rotate, but the object doesn't... Now parent the empty to the sphere, so that when you grab the sphere you don't forget to move the empty accordingly. (alt-p after selecting first the empty then the sphere). You can now create really cool animations, where the earth rotates around the sun and on itself, but you only need to worry about the revolution of the earth, not its own rotation. I haven't done that part of the animation, but give it a try, and admire your skills at making earth go round around the sun... Or not!