Hello! My name is Angela and Grant has given me the chance to write a guest entry in his blog. I thought I would talk a little bit about UV mapping.
What is UV mapping?
UV mapping “is the 3D modeling process of making a 2D image representation of a 3D model” (UV mapping, 2011). If you want to get technical with it, it is hard to explain and there are even math equations to for finding UV coordinates for a sphere. The reason why the letters U and V are used, is because “X, Y, and Z are already used to describe the 3d object in model space” (UV mapping 2011). Once your 3D model is mapped out, you can then save this file and export it into Photoshop to apply textures or colors. Then, you bring it back in to Maya and lay the texture on top of your model.
Let me show you a quick example of how to texture a sphere with the world map.
The first thing I did was create a simple sphere.
Then I clicked on WINDOW > UV TEXTURE EDITOR
You should get something that looks like this.
Once the window UV Texture Editor window is open, I held the right mouse button and clicked UV. Then I highlighted all of the white squares. The image of the world map is not square but a rectangle shape so after clicking all of the white squares, or the UV’s, I scaled it to the best of my judgment to match the shape of the world map image.
Then within the UV Texture Editor window, click POLYGONS > UV SNAPSHOT and save it to somewhere you can easily find it, like the desktop. The UV’s must be selected or else it won’t let you save the image.
Next open the UV Snapshot and the image of the world map with Photoshop.
Copy the image of the world map, and paste it onto the UV Snapshot image.
Next what I did was, take the UV Snapshot image, and invert it (Ctrl or Cmd + I) so that it is a white image. I placed the image of the world map layer on top of the UV snapshot image. Then scale the image of the world map to within the borders of the UV snapshot.
Next, save this image to an easily locatable file. Make sure that the UV Snapshot image is NOT visible, or else you will see lines on your 3D model texture.
Next I right clicked on the sphere in Maya, and clicked on ASSIGN NEW MATERIAL.
I decided to use a Phong shader. After that under the color tab, you click on the 4 checkered box on the right side, and then click on FILE. Then choose the file where you saved your Photoshop image and hit “6” on your keyboard.
There you have it! You have textured the world!