In the second part of the Thor Hammer tutorial, Chandan Kumar will show you how to unwrap each element of the model and pack the UVs before moving into Photoshop to create the textures. You'll wrap up the project by heading back into Maya to create shaders, setup scene lighting and do the final render.
1. Unwrapping the Head
Open the file, which we saved at the end of part 1.
We will first unwrap the head of the hammer. So, with the head of the hammer selected, press Shift + I, to isolate the selection.
Now, go to Create UVs > Planar Mapping, and click on its option box.
This opens the Planar Mapping Options window.
Now, go to Face selection mode and select the top and bottom faces as shown. These are the parts that we will apply planar mapping to.
After selecting the faces, look at the axis direction of the selected faces. And then set the same axis in the Project From: field of the Planner Mapping options, according to the axis of the selected faces in the viewport.
As you can see in the image, the direction of the selected faces is the Y-axis. Therefore set the same Y-axis in the planar mapping options.
Now click on the Apply button to apply the planar mapping to the selected faces, and then minimize the option window. After applying the planar mapping, you will see a red T shape in the viewport.
When you click on this T shape, it turns a yellow color and the manipulator appears in the viewport. The Manipulator is a tool, in which you have three combined tools - The Move tool, Scale tool and Rotate tool. Choose any one according to your needs.
Now, go to Edit UVs > UV Texture Editor, to open the UV Texture Editor window.
You can see the unwrapped faces in the UV Texture Editor window, but the width of the unwrapped faces is not wide enough, according to the model in the viewport. So, in the UV Texture Editor, press and hold the Right Mouse button and select UV.
Click and drag with the mouse pointer to select all the UVs (as shown in the image), and then Scale them horizontally using the Scale tool.
Select a UV and go to Select > Select Shell, and then move the selected UVs. With the help of this option, you can select and move all the overlapped UVs.
With the overlapped UVs selected, go to the Tool menu and click on the Smooth UV Tool.
Now you can see that the Unfold and Relax options appear on the screen. Use the Unfold option to unfold the overlapped UVs.
Just click on Unfold, and then drag to the right side. Drag until all the UVs are unfolded.
I would like to tell you how to check whether your UVs are overlapped or not. There is a switch that will show which UVs are currently overlapped. On the main menu bar there is an icon called Toggle shaded UV display. After clicking it, it will show non-overlapping faces in Blue, and overlapping faces in Red.
Let’s unfold the other UVs just like we did before. When you try to unwrap the other UVs set, you can see that the UVs are getting twisted. This is happening because this UV set is from the bottom of the hammer. So we need to flip it vertically, and then unfold it.
There are two options in the menu bar of the UV texture editor. The first one is Flip Horizontally, and the other is Flip Vertically. So select all of the UVs and then Flip them vertically. After that you can unfold it.
Now, select the side faces of the hammer and follow the same procedure from Step 2.
The selected side faces are unwrapped as shown in the image below.
Here we don’t need to unfold the UVs, because there are no overlapping faces here.
Now, select the remaining faces on both sides and unwrap them.
Now, since you already have an idea on how to unwrap a plane surface. Unwrap the remaining faces following the same procedure.
After unwrapping the faces, Scale them to make their width the same as the other faces.
First repeat Step 6, and then go to Tool > Smooth UV Tool, and then unfold the overlapped UVs the same as we did in Step 7.
This is the current position of the UVs in the UV Texture Editor. Let’s change the sequence of the UV sets.
So position the UV sets as shown in the image below.
Look at the below images. In the first image, I have selected the top and left side UVs. And in the second image, I have selected the bottom and right side UVs of the hammer. Keep the UVs together in the UV texture editor, as they are connected together in the viewport. This is quite necessary for texturing later in Photoshop.
So, this is the time to check whether the Hammer UVs are flattened perfectly or not. Go to Window > Rendering Editor > Hypershade to open the Hypershade window.
In the Hypershade window, pick the Checker material.
You will see a Checker 1 node in the work area. Now, with the hammer selected in the viewport, Right-click on the Checker 1 node, and choose Assign Texture’s Material to Selection from the fly out menu.
As you can see, the checker material has been applied to the hammer. Sometimes, you might not see the material applied on the mesh in the viewport. So press 6 on the keyboard, to make the texture/material visible in the viewport.
Look at the checkers on the hammer. They all are not of equal size and not perfectly square either. If all the checkers are not of equal size and perfectly squared, it means the UVs are wrong. So we have to fix it by adjusting the UVs further.
Select the UVs in the UV Texture editor and Scale them to make all the checkers an equal size and perfectly square.
Similarly we have to adjust all the UV sets.
2. Unwrapping the Handle
Now, let’s unwrap the handle of the hammer. Select the hammer’s handle and Isolated the selection.
Then go to the Create UVs menu, and click on the Cylindrical Mapping option.
You can see now the cylindrical papping has been applied to the handle.
Now first of all we need to apply the checker material to the handle. With the handle selected, Right-click and go to Assign Existing Material > Checker 1Material. Just like this, you can apply the checkers onto any object.
Go to Edit UVs > UV Texture Editor, to open the UV Texture Editor and then select the UVs for the handle.
Scale the UVs Vertically to make the checkers perfectly square.
Go to Tool > Smooth UV Tool in the UV Texture Editor and unfold the overlapped UVs.
3. Unwrapping the Snake Design
Now, we will unwrap the snake design carving on the hammer. So select a piece of the snake design.
Then go to Create UVs > Automatic Mapping and apply automatic mapping to the snake design. After that, open the UV Texture Editor. Here you can see that the top face of the design is unwrapped perfectly, but the side faces are unwrapped and broken into different pieces. To make it look perfect and seamless, we have to stitch all the separate parts together.
Now, let’s look at how to stitch these side faces together. In the UV Texture Editor, press and hold the Right Mouse Button and then choose Edge. Select an edge of the first UV set from the side faces that have been unwrapped. You can see in the image below, when I select an edge, another edge is then selected automatically. This is the corresponding edge of the selected edge. It means that the second edge will be stitched with the first one. Like this, you can easily find which edges should be stitched together and which ones shouldn't.
After selecting an edge, click on the Move and Sew button, in the Tools menu of the UV Texture Editor.
When you click on the Move and Sew button, the two separate UV sets are then stitched together. Stitch all the UV sets together in this manner.
So, now you can unwrap all the parts of the snake design.
If the length of the side faces are too large. You can divide them into two or three parts.
4. Packing the UVs
After unwrapping all the parts of the hammer. Place all the UVs inside the box in the UV Texture Editor, as shown in the image below. Remember one thing, any instanced objects only need to be unwrapped once and the other duplicates will be unwrapped automatically. You can see in the image below, I unwrapped the handle rings and the snake design only one time, because I don’t need to unwrap their duplicates. So, here is the completely unwrapped hammer.
Now with the hammer selected, go to the Polygons menu inside the UV Texture Editor, and click on the UV Snapshot option.
This opens the UV Snapshot window. Browse to the file location where you want to save the file, and set the file size resolution to 2048 pixels for both the Size X and Size Y columns. Then set the format of the snapshot to PNG. Now, press OK and your UV snapshot will be saved to the location you’ve set.
5. Texturing the Hammer
After completing the unwrapping, we can now start to texture the hammer. Open Photoshop and import the hammer’s UV image.
Now create a new layer by clicking on the New Layer button.
Fill this new layer with a black color and then rename this layer ‘Background’, and also rename the UV layer ‘Hammer UVs’. Keep the UVs layer at the top. Now you can see that the black background layer is below the UVs layer, so the UV layer can be easily seen.
Now click on the color picker and choose a grey color. You can use the color code #9a9a9b, to match with the color I have used.
Now create another new layer and then with the help of the Brush Tool, fill all parts of the hammer parts with the grey color. Remember, always work on a new layer, so you can make changes later to only that texture layer. Also give the layer a suitable name so you can recognize it easily.
Create another new layer, and pick the Polygonal Lasso Tool from the tool bar.
Now make the selection shown in the image below.
Then select this exact color #2b3944 from the color picker.
And then fill the selections with the selected color.
Here I will use this image of scratched steel for texturing.
Put this texture over the hammer’s UVs and rename it "Scratched Texture".
Press Ctrl+T, to select the scratched texture as a transform selection.
Now, increase the size of the scratched texture using transform selection.
Pick the Clone Stamp Tool, or press the S key on your keyboard.
Now start cloning the texture to fill the ends of the image.
Select the snake design background layer (the blue color layer), and place it above the scratched texture layer.
Just like this, texture all parts of the hammer head.
Select all the scratch texture layers, and then press Ctrl+E to Merge all these layers into one.
Now turn off the scratch texture layer by clicking on the eye icon for that layer.
Now we have to make some spots on the grey texture to make it look dirty. Select the Brush Tool and then click on the Arrow button, that I’m showing below marked with a red arrow.
This opens a new window on screen. Now click on the Arrow icon marked below, to open the Brush menu. Here select the Wet Media Brushes at the very bottom. This will open the wet media brushes list. Select the Dry Brush on Towel preset.
Create a new layer and Rename it "black spots". Increase the Brush Size to 200 units, and decrease the Opacity to 51% and the Flow to 30%.
Use this brush very carefully to make dirt spots on the grey texture.
Now put the scratched texture layer over the Black spots layer, and then change its Blending Mode from Normal, to Overlay.
Repeat the same procedure to texture the cylinder cap on the top of the hammer.
Now, let’s move onto the handle of the hammer. Create a new layer and rename it ‘Handle’. Make a selection around the handle using the Polygon Lasso Tool, and then fill the selection with an orange color (#632f0a) as shown in the image below.
Create a new layer and rename it "handle cap", and fill it with the grey color.
Similarly, add the grey color to the handle rings, and handle cap UVs.
Now we’ll texture the snake design. First of all, pick the same color #9a9a9b, which you can see in the image below.
Make the selection of the snake design with the help of Polygon Lasso Tool.
Then fill the selection with the grey color.
See the blue texture on the hammer. It looks very plain and too clean. So we need to make it a little dirty. Pick the Clone Stamp Tool and then place the scratch texture layer, above the snake design background layer.
Reducing the Opacity of the tool to 65%, and clone the scratch texture over the blue color textures to make it dirty.
Now pick the Dry Brush on Towel preset from the Brush Menu, and draw some light strokes on the blue texture.
Now only one part is remaining for texturing, and that is the leather strap. I’m using this leather texture to texture the strap, but you can use your own.
Decrease the size of the texture by pressing the Ctrl+T, and then transform the selection. After that, move the leather texture layer below the UVs layer.
Select the leather texture and press Ctrl+J to make a duplicate copy of the texture, because one copy of this texture will not be enough as you can see.
Select all the copies of the leather texture layer, and then press Ctrl+E to Merge them into one layer. And rename this layer ‘Leather Strap Texture’. In the image, you can see a faint line between the copies of the leather. So pick the Clone Stamp Tool and fix this problem by cloning the texture over those lines.
Delete the extra texture, because it is covering the hammer UVs and also increasing the file size.
Pick the Dry Brush on Towel preset from the Brush Menu, and then draw a line with a dark green color on the UVs of the cylinder (which is the top on the hammer.) The color should not be too dark, it should look like rust from the corners.
Create a new layer and rename it ‘rust’. Now create a circle selection and press Ctrl+Shift+I to inverse the selection. Now pick the Rough Ink Brush from the Wet Media Brushes, and reduce the brush's Opacity to 70%. Then draw on the border of the circle from the outside according to the image shown below.
We also have to add some rust to the bottom of the hammer, where the handle attaches. Make some spots on the bottom using the Dry Brush on Towel preset, from inside the Wet Media Brushes menu. You need to use the rust layer when making these spots.
Now the texturing work is complete. Save the texture in .jpeg format. And then select all the layers, except for the UVs and background layers. And go to Layer > Duplicate Layer to duplicate the selected layers, and then press Ctrl+E to Merge them into one.
After merging the layers, rename the layer 'bump map'. Then go to Image > Adjustments > Desaturate, to convert the bump map layer into a greyscale image. This will become the Bump map for the hammer.
6. Creating the Shaders
Go back to Maya and open the Hypershade window by going to Window > Rendering Editor > Hypershade.
Pick a Lambert shader from the materials list.
Double click on the Lambert icon. After double clicking, you can see its options on the right side of the screen. Now rename the Lambert material ' hammer_texture'.
Now click on the checker box icon next to the Color option in the attribute editor.
This opens the Create Render Node window. Here select File from the list.
Click on the yellow folder icon, and open the texture of the hammer you saved from Photoshop.
With the whole hammer object selected, Right-click and choose Assign Texture’s Material to Selection.
This will apply the texture onto the hammer model.
Now click on the checker box icon next to the Bump Mapping option in the attribute editor.
Just like we did previously, locate and apply the Bump map to the channel.
Click on that little black arrow marked below, and you'll get an option to set the value of Bump.
You can set the Bump Depth value as your require.
Now it time to do some lighting and shading. For this we will change some shaders. Because the basic materials will not give us exact results, for the chrome or stone at the time of the lighting. Before starting the lighting, shading and rendering, we must smooth all the mesh objects. Now, select the handle of the hammer and Right-click and select Material Attributes.
Change the material attribute from Lambert to Phong.
Then change the Reflectivity value to 0.000, under the Specular Shading rollout.
The handle rubber part is fine according to the Phong material, but now we need to change the shading for the metal parts. So, for this we will create a new Mentalray material.
Go to the Hypershade window and again select a mia material, the select the metal parts of the handle and apply it.
With the mia material1 selected, press Ctrl+A to open its attribute editor. And click on the Presets option to change the mia material to stained material.
Change its Glossiness value to 0.500, under the Reflection rollout.
Select the faces around the top, as shown in the image. And apply the same material (mia material) to them.
Now, it’s time to change the hammer head shader. For this, we need a different material, or we can copy the same Phong material we used for the handle of the hammer earlier. Go to the Hypershade window, select the Phong material and first press Ctrl+C to copy the shader, and then Ctrl+V to paste it. You'll then see the pasted Phong material listed.
Rename it 'head' and assign it to the selected head only.
Now open the attribute editor for the head phong shader, and change it to a Blinn.
After that, we need to make some changes in the options, like the Eccentricity, Specular Roll Off, Specular Color, Reflectivity, etc.
7. Lighting and Rendering
Now the shading work is done and it’s time to do the lighting setup and rendering. Before starting the lighting setup, we need to make a basic scene first to set the camera, or a bookmark for a suitable render angle. So create a Plane object in the Top view, and place the hammer on the plane.
Now change the renderer to Mental Ray.
Now we'll start by doing image based lighting. Open the Render Settings and go to the Indirect Lighting option. Here inside the Environment rollout, click on the Create button next to the Image Based Lighting option.
This opens the Attribute Editor window. Here click on the Create option, and choose any HDRI image from your computer.
This will create an HDRI Sphere in the scene.
Now, go to Create >Lights >Spot Lights.
This creates a new Spot Light in the scene. Select it and place it at a good position.
We need to change some attributes for this light. So press Ctrl+A to open the Attribute Editor. Change the Light Intensity value to 0.500 and turn off the Emit Specular option. Set the Cone Angle to 65.795, the Penumbra Angle to -10.000 and the Dropoff to 6.335.
Now hit the Render button and see the results.
To make it look more effective, we need to place a secondary light. Just like with the first light, we have to create another Spot Light and place it somewhere it can illuminate the hammer efficiently.
This time we will switch on the Shadows option, check the Raytraced shadows box and change the light’s attributes as well.
Now let’s see how the render looks. It still needs some rectifications.
Go to Create >Lights >Area light and place this new Area Light above the hammer.
Now open the Attribute Editor for this Area Light, and give it a light orange color. Set its Intensity value to 0.500 and turn off its Specularity. We also need to turn on the Light Shape option, and change the type to Rectangle and the High Sample value to 16.
Open the Render Settings tab, and change the image size to HD 720.
Now open the Quality tab, and change the Max Sampling Level to 2 and the Multi Pixel Filtering option to Gauss.
And at last, turn on the Final Gathering option.
After fixing some problems/errors/bugs and playing with the parameters of the lights, here is the final render. This looks pretty good, however you can do a lot more. Remember, the higher the quality, the longer the rendering time. After rendering the final version, you can do a small color correction and some touch up in Photoshop to make it look much better.