Create a Stylized Strawberry Character with ZBrush and Keyshot
In this tutorial you'll learn how to sculpt a stylized strawberry character from scratch using ZBrush and how to render with Keyshot. Topics include modeling with Shadowbox, using radial symmetry to sculpt and position objects, working with subtools, posing with the Transpose tool, retopologizing meshes with Qremesher, as well as working with various brush types and masking techniques in ZBrush. You'll then learn how to export the completed character to Keyshot, and bring him to life with textures and materials.
After completing the project here on Cgtuts+, head over to Psdtuts+ to learn how to create a print ad using this character and Photoshop in:
The following assets were used during the production of this tutorial.
1. Creating the Strawberry Shape
Select the Sphere 3D from the Tools Menu, and convert it into a Polymesh by clicking on the Make Polymesh button. Now go to the Deformation Submenu under the Tool Menu, and adjust the Perspective slider as shown, to a quantity of 100 on the Z-axis.
Increase the resolution of the mesh by pressing Control+D, divide it in until you have 4 subdivisions levels.
Now go to the Transform Menu and activate Symmetry, by clicking on the Activate Symmetry button. Turn on Radial mode (R) for the Z-axis as shown, and set the value of the RadialCount field to 18.
In the Brush Menu, select the Standard Brush, with Alpha 35 and the Drag Dot stroke configured. Now, with Zsub mode active, start sculpting the seed's cavities as shown. Adjust the Brush Size and Z Intensity to a logical size, and alternate the cavities as shown. On the narrower parts, such as the tip and the bottom, start decreasing the RadialCount value to 16, 14 and 12.
Next, go to the Masking Submenu and activate the Mask By Cavity option, this will mask all the cavities. Then press the Blur Mask button to blur the mask edges a bit.
We get the following result.
Finally, go back to the Deformation Submenu, and enter a quantity of 12 in the Inflate Balloon slider on all axes (X,Y and Z).
We get the strawberry shape already.
2. Sculpting the Seeds
Once again, start with a Sphere 3D, and modify its shape applying the following Perspective and Size adjustments in the Deformation Submenu. Notice the corresponding axis where the deformation will be applied.
We will get the following seed shape, in this case it will not be necessary to increase the mesh subdivision level. As they are going to be a very small part of the model, we can leave it at 1.
Place the seed on the canvas in a frontal view, as shown in the previous step. Then open the Brush menu, and at the bottom, convert it to an insert mesh brush by clicking on the Create InsertMesh button.
First, duplicate the strawberry tool and delete all of its subdivisions levels to allow us to use the insert brush.With the just created insert brush selected, again activate Radial Symmetry on the Z-axis with the same Radial Count numbers we use for the strawberry. And start placing the seeds in the corresponding cavities. In the Brush menu, adjust the Depth of the brush to a 0 Imbed amount.
Activate Move Mode and while holding down the Control key, drag on the strawberry surface to create a mask of the whole body. Once done, Invert the mask to mask all the seeds.
Now in the Visibility Submenu press the HidePt button. This will hide all the unmasked geometry. Next go to Geometry > Modify Topology and press the DelHidden button, to delete the duplicated strawberry shape.
Finally we will have two subtools. One of the shape, and one of the seeds.
3. Sculpting the Leaves
For the leaves we are going to use a ShadowBox technique, open the Lightbox browser, and in the Tools Folder there is the ShadowBox128 Ztl. Double click on it to select it, and then drag and drop it onto the canvas. In the Transformation Menu, set the following Symmetry settings.
Start painting the leaf mask, holding the Control/Command key. As we have a RadialCount of 8 for the symmetry, we'll get eight leaves. Once the mask is painted, in the Geometry Submenu, turn off the ShadowBox button to generate the mesh.
Now go to the Deformation Submenu and adjust the Size slider, with only the Z-axis activated, to get the right thickness for the leaves.
Start sculpting the leaves. Use the Move Brush to create the irregular edges, and use the Dam Standard Brush to sculpt the nerves and folds.
Once the sculpting process is finished, append the new leaves tool to the strawberry as a new subtool. Re-size it if necessary
4. Sculpting the Face
First of all, as we will sculpt two different faces, duplicate the strawberry tool. I prefer to do it this way instead of creating layers, to have less restrictions.
With the Smooth Brush, remove all necessary seed cavities to create the space needed for the face. Next, with Symmetry activated on the X-axis, paint a mask for the ocular cavities as shown.
Here, there are several ways to achieve this result using different brushes or deformation adjustments. I used the Move Brush to push in the surface to create the cavities. Once you have them created, smooth them a bit with the Smooth Brush.
For the mouth, draw a mask and invert it (Control+Left Click on the Canvas.) Then in the Deformation Submenu, use the Inflate slider, to apply a negative inflation on the Y-axis to create a cavity.
To sculpt the corner of the lips, start masking the lower lip, and then with the Move Brush, bring the upper lip down.
To sculpt the lips, follow the previous techniques to create masks to isolate each one. With the Inflate Brush, create the volumes, following with the Move Brush to create the shapes. Use the Dam_Standard Brush with Zadd mode activated, to sculpt crisp edges, and use the Pinch Brush to close them on the extremes.
5. Replacing the Seeds
Once the face is sculpted it will be necessary to relocate and delete the necessary seeds. To delete the unwanted seeds (those that are in the ocular cavities), activate Move or Rotate Mode and a Transpose Line will appear. Then while pressing the Control/Command key and dragging on the desired seed, start masking all the seeds one by one.
Using the technique we used before to delete the selected seeds, hide and delete the unmasked seeds.
Now, it will be necessary to sculpt the cavities again (which we remove when sculpting the face.) Again select the Seed Tool we created before, and place in on the canvas facing its front view. Then go to Alpha > Transfer > GrabDoc. With this we will grab the depth information of the seed and use it as an Alpha. Select the Standard Brush and the Drag Rectangle, and set the Seed as the Alpha. Then sculpt the cavities again, but this time place them following the face forms.
Use Move or Rotate Mode with the Transpose Line, to relocate each seed to its cavity.
Finally using the Inflate Brush, adapt the cavities to the seeds and to the face forms.
6. Sculpting the Chocolate Hat
On the strawberry Tool, draw a mask over the upper part and extract the geometry using the Extract button in the Subtool Menu, with the following settings (shown below). Before extracting, first select the lowest subdivision level to get a lower poly count mesh that's easier to handle.
Now in the Geometry Submenu, use the Qremesher option to create a more homogeneous mesh of the hat's extraction.
Subdivide some more levels the mesh, and then activate Radial Symmetry on the Z-axis. A Radial Count of 8 will be enough. Use the Form Soft Brush to create the volumes of the chocolate swirls.
To create the swirl shape, go to the Deformation Submenu and adjust the Twist slider with only the Z-axis activated.
Finally, using masks and the Move and Inflate Brushes, sculpt the mesh creating folds and forms.
7. Adding the Eyes and Eyelids
Append a 3D Sphere to the Subtool Menu, and by using the Deformation Submenu, re-size it with the Size slider. Then using the Transpose Line in Move Mode, position it in the ocular cavity. Once in place, hit the Duplicate button to create the other eye, now go back to the Deformation Subpalette and Mirror it on the X-axis. Finally Subdivide each mesh a bit to have a smoother surface
To create the eyelid, mask a portion of the 3D Sphere we created before, and hit the Extract button with the following settings (shown below). Don't forget to press the Accept button to create the new geometry.
Now the eyelid is created and appended to the Subtool Menu. Use the Transpose Line in Move Mode to push it a bit forward, now change to Rotate Mode and tilt it up a bit.
Again, Duplicate and Mirror it to create and place the other eyelid.
Finally we will create the cornea of the eye. For it, Duplicate the eye 3D Sphere and in the Deformation Submenu, apply a value of -8 to the Inflate slider. Use Transparent Mode, from the Transform Menu, to see the result better. You will see two spheres, an outer and an inner one. Finally Subdivide each mesh a bit to have a smoother surface.
8. Refining the Expression
Getting to this stage, I thought that eyebrows would enhance the overall expression. To create them, use the Extract technique we saw in the previous steps - painting a mask, extracting new geometry, and positioning it with the Transpose Line.
Tip: Once the new mesh has been extracted, use the Polish slider in the Deformation Submenu to clean up the mesh and make it more homogeneous.
With the Move and Inflate Brushes, refine the expression, marking the cheeks, and adjusting the eye contours.
9. Posing the Leaves
Now it's time to pose the leaves in an irregular manner. Change to Rotate Mode, then while holding the Control/Command key, create a topological mask on the desired leaf. This means that the mask will follow the polygonal distribution, helping us to place it better. Once the mask is in place, use the Transpose Line to rotate the unmasked area. It will be necessary to do this one by one, and rotate more than one portion of each leaf
Now, with Move (or the Move Topological Brush), create some irregularities to give the leaves a more realistic finish.
10. Merging and Exporting
All the parts are now sculpted, detailed and in place, but to import to Keyshot it will be better to have all of them together. In the Plugin Menu, you will find the Subtool Master plugin, press the Merge button and select the Merge Only option. Before you do this, check that all the subtools are on their highest subdivision level.
Finally to export the resulting merged subtool, go to Tool > Export, and save the Obj file on your hard-disk.
Here is the final ZBrush model, and the optional frightened strawberry. To sculpt that one, just create the cavity of the mouth like we did the ocular cavities, remove the eyelids, transform the position of the leaves to give him a scared expression, and sculpt different forms on the chocolate hat.
11. Keyshot Rendering
Run Keyshot and Open the strawberry Obj file that we export from ZBrush. First, you will get the following window. Under the Advanced menu, check on Keep Individual Parts, and choose Group by Materials.
The model will appear on the screen, but in the wrong orientation. To correct this, place the cursor on the model, right-click and select the Move Object option.
On the bottom of the screen a small menu will appear. Select the Rotate option, and then using the giro controller, rotate the model.
Next select the Translate option, and then using the arrows, translate the model to place it on the ground.
Now, let's start to assign materials. First it will be necessary to unlink each part of the model so we'll be able to assign a different material to each one. Place the cursor over the desired part and with the right mouse button, select Unlink Material, do this over each part.
Attaching materials in Keyshot is quite easy. Open the Library Menu, and select the Materials tab, then just drag over the selected material to the desired part. For the strawberry's body, we can select the Paint material: Paint - gloss red.
To give to the surface a more rough finish, double left-click on the part that has the material assigned, and the Project Menu will appear. In the Material Tab > Texture Tab, check the Bump texture box and a browser will pop up to select the texture. The Cast_Iron_Bump will work for our purposes.
Repeat the same operation again, to assign the material to the seeds. This time the Wood material: Light Oak will work.
Same process for the chocolate hat and eyebrows, the Paint - gloss deep red material will do.
Double click on the part, and in the Material Tab > Properties, apply the following amount of Roughness 0.060, this will give us a less shiny chocolate surface.
For the leaves, the Paint - matte green will work.
Open the Project Menu again and in the Material Tab > Texture, check the Color box. Then browse and select the leaves texture provided in the tutorial assets. Select the Box Map option to apply it to the mesh. It will be necessary to adjust it a bit by activating the Mapping Tool button.
As we have two spheres for the eyes, it will be necessary to hide the cornea first to assign the material to the eye. Place the cursor on the part, then right mouse click and select Hide Part.
Apply the Paint - gloss cream material to the eyeballs.
Now go to the Material Tab, in the Project Menu and in the Labels tab, check the Label box. Browse and select the Eye texture provided with the tutorial assets. Adjust the Scale value as shown, and click on the Position button to place the texture in the right place. Once placed, deactivate the Position tool option and repeat the same operation for the other eye.
To make the cornea visible again, right mouse click and select Show All Parts.
Now apply the Glass basic white material to the cornea.
Here I decided to move the eyelids a bit to open the eyes more. Place the cursor over the eyelid, right mouse click and select Move Part, then use the Translate and Rotate options to reposition them.
Open the Library Menu and go to the Environments Tab, and choose the Hdri Forest by double clicking on it.
Now in the Project Menu (spacebar), hide the image and replace it with a background color. Then apply the following settings to the Environment controls.
Finally to prepare the image for the output render. Go to Render > Render Settings and in the Output menu, set the file and resolution, and things such as the output file format.
In the Quality section, you will find all the relative controls for the final render quality. Go to Help > Online Manual to learn more about how each one works.
We are now finished and our character is complete! Remember to head over to Psdtuts+ to learn how to create a print ad using this character!