In this 3 part Maya workflow tutorial you will learn how to model, texture, and render a Katana, the legendary Samurai sword. For the modeling portion, we will use Maya's basic polygon editing tools, while UVlayout will be used to create the UVs, and of course Photoshop to create the textures. We will also briefly cover Mental Ray for rendering the final image.
Additional Files/ Plugins:
Here we are, beginning from where we left off in Day 1. In this part of the series we will prepare our meshes for texturing by laying out the UVs. For this, we are going to use Headus UV layout to make the boring process of laying UVs, much easier and quicker. First let us subdivide our mesh so that we get less distortion later.
Go to "Edit > Delete All by Type > History".
Select all of the pieces, and under "Polygons" go to "Mesh > Smooth".
To use the pieces in UVLayout we will need to export them as .obj files. To do so, first we need to make sure that the plug-in is loaded. Go to "Window > Settings/Preferences > Plug-in manager".
In the plug-in manager, make sure that "objExport.mll" is loaded. If it isn't, check the boxes near its name.
Select the blade, and go to "File > Export Selection..."
In the new window, for file type choose OBJexport(*.*), and for the file name use "bladeUV_out". By default it will save it in the "data" folder of your current project. Click "Export".
Repeat these steps for the Saya and the Handle. The Cloth Bow will need some work first, and the Tsuba, Habaki, and Fuchi will need only a Maya or Mental-ray material, and thus will not need to be UV'd.
Because we will never see the inside of this part, we will delete the faces that can't be seen. Be sure to leave enough faces to hold the edge. Note: To make selecting the faces easier, start by selecting the edge loops that are in the middle.
Hold the Ctrl key, now right click and hold and select "to faces". This will convert the selection from edges to faces.
After the faces are selected, delete them. This will make your scene lighter and laying out the UVs easier. Now you can export it like the others.
Now we are ready to work in UVLayout. For those of you who haven't worked with UVlayout before, you have nothing to worry, I will take you through it as we go. After it loads up, press the load button.
Click the dir button and navigate to your data directory. Press OK.
In the load window, all the obj files will be shown. In the "Load Options" windows, make sure that "Poly" and "New" are pressed. Then click on the name of the blade obj, and click load.
Now you are in the edit window. You can move in it just like in Maya. The first step is "cutting" (defining the seams). First we will cut out the blood grooves. Place your pointer over the edge that you want to cut out, and press 'c' on your keyboard. This will define the edge that will be cut later.
Add another selection line on the other side of the groove.
To deselect a part of an edge that you don't want, place your mouse pointer over the edge and press 'w' on your keyboard.
Make sure the selection line is all the way to the end of the blade. If it stopped somewhere along the edge, just place your pointer and press 'c' to continue it.
Place your mouse pointer over the piece that you want to cut out and press 'Enter' on your keyboard. Now you have successfully cut out a piece. Repeat the same process for the blood groove on the other side.
To move the cut out piece out of the way, place your mouse pointer over it, press the space key on your keyboard, middle click, hold, and drag.
Next, we will cut out the back piece. Start at the tip of the blade, again make sure it goes all the way to the end.
All that's left is to separate the sides of the blade. Start at the tip of the blade, make sure it goes all the way to the end.
In the main window of UVLayout, press on the display button to open up few more options. Now you can switch between the edit window and the UV window.
To flatten a piece first you need to drop it to the UV space. To do this, place your pointer over a piece and press the 'd' key on your keyboard. Next, press the UV button under the display options.
When in UV view, place your pointer over the piece and press and hold the 'f' key on your keyboard. With this you will start to flatten the piece. A green color indicates no distortion, a blue color indicates stretching, and a red color indicates pinching. If you notice any light blue or red areas, don't mind them, as they probably won't be noticeable.
Go back to the Edit window and drop the next piece, then go back to the UV window and flatten it. Repeat this for all of the pieces.
After you have flattened all of the pieces, press the 'save' button. Where it says bladeUV_out, replace the word 'out' with 'in', and then press the 'save' button.
Load the clothbowUV_out.obj. For this piece we only need one cut. Make sure it's selected all the way around to the inside.
Drop this piece in the UV space and flatten it. Note: If you don't want to hold the 'f' key all the time, click the 'optimize' button and press the 'run for' button.
You may have a little distortion, but it's OK since its going to be within the folds and it won't be noticeable. Save it as clothbowUV_in.obj.
Load the handleUV_out.obj. For this piece we will need only two cuts. One to cut out the bottom...
and another cut along the side of the handle.
Flatten it, and save it as hanadleUV_in.obj.
Load the sayaUV_out.obj, and first cut out the tip.
Cut out the extruded part on the beginning.
You don't need to flatten this piece. There won't be any texture on it.
Add another cut along the length of the Saya.
Flatten it, and save it as sayaUV_in.obj. With this you have finished laying out the UVs in UVLayout.
Go back to Maya and delete the Blade, Handle, Cloth Bow, and Scabbard.
Go to "File > Import". In the "Import" window, navigate to your "data" folder, and import the "_in.obj" files one by one .
Now we have our new meshes with laid out UVs. Select the Blade and go to "Window > UV Texture Editor".
As you can see the UVs are all over the place. To properly use them we will need to fit them in the 0 to 1 space.
Before that, we need to do some more work on the Blade UVs. We will connect the side pieces with the back piece. Zoom in to the back piece, and go to edit edge mode (Right click > edge).
Select one of the outer edges, press and hold the Ctrl key then "right click and hold > to edge loop".
In the UV texture editor go to "Polygons > Move and sew UV edges" or press the move and sew edges icon. This will move the piece and sew the shared edges.
Go to UV edit mode "right click > UV ". Select some UVs of the new piece and press and hold the Ctrl key, then "right click and hold > to shell".
With the rotate tool, rotate the shell, so that it stands vertical.
Grab the shell of the blood groove, and set it vertical next to the blade. Do this for both pieces.
Select the shells, and using the scale tool, scale them to fit into the 0 to 1 space. Scale all of the pieces together, so that the proportions remain the same.
In the UV texture editor go to "Polygons > UV snapshot". In the new window, for file name enter "outUV_blade", for the size in x and y enter 2048, and for image format choose JPEG. Press the OK button. With this you have created a UV snapshot, which you can use as a guide when painting the textures.
Select the Handle, and open the UV texture editor.
Select both shells and scale them in the 0 to 1 space.
Make a UV snapshot. For file name enter "outUV_handle"; x and y size = 1024.
Select the Cloth Bow, and open the UV texture editor.
Grab the shell and scale it down into the 0 to 1 space.
Make a UV snapshot. For file name enter "outUV_cloth"; x and y size = 512.
Select the Scabbard, and open the UV texture editor.
Select the 3 shells and scale them into the 0 to 1 space.
Make a UV snapshot. For file name enter "outUV_saya"; x and y size = 2048.
We are finished with laying out UVs and preparing for texturing. Next time we will discuss the texturing and rendering!