Creating Animated Pupil Reflex
Setting up the basic shape
1. Create a sphere
2. Rotate the Pitch (P) 90 degrees.
3. Make the sphere editable by clicking the Make Object Editable Tool or hit "c" on your keyboard.
4. Rotate the axis Pitch back to 0 degrees, using the Object Axis Tool.
This way, the iris that we are going to make is facing you, with appropriate polygons to shape it.
5. Save as "pupil project" on your desktop
Shaping the iris
1. Select the Polygon Tool to go into the so-called Polygon Mode.
2. Zoom and rotate within the view so we can see the first three rings of polygons.
3. Select the Knife. In the Attributes Manager, change the Mode from line to loop.
4. Make a cut just outside the second polygon ring by clicking the mouse once you've dragged the yellow line into the right position.
5. Select the Live Selection Tool
6. Select the first two rings of polygons by dragging the cursor over them.
7. Drag the selected polygons towards you along the arrow on the Z-axis (it will turn yellow when the cursor is in place) a little bit or type -95m in the Z-Axis Position Box.
Renaming and setting up the shape for the cornea
1. In the Object Manager rename "Sphere" to "inside eye".
2. Create a HyperNURBS cage and drag the "inside eye"-object into it
3. Select the HyperNURBS cage and copy it by dragging it downward in the Object Manager while holding down the Control-key.
4. Double-click the new "inside eye"-object and rename it "outside eye".
5. Hide "outside eye" for now: click both small grey dots next to it until they turn red
6. Still in the Object Manager, select the "inside eye"-object
Shaping the opening for the pupil
1. Select the inside eye object. With the two rings of polygons selected, go to the main menu and choose "Shrink Selection" from the Selection-menu, or hit u and k quickly after each other on your keyboard. Only one ring of polygons will remain selected.
2. Change the Z-position to -90.
3. In the main menu, choose "Edit > Delete" to delete these polygons and make a hole.
4. In order to give some thickness to the edge of the iris like in real life, we'll extrude the eye: Select the Extrude Selected-tool and make sure "create caps" is active. We want the whole eye to have some thickness. In Offset, type "-3" and hit Apply.
5. Not all polygons are now pointing outward. Select them all (Selection > Select All) and choose Function > Reverse Normals.
Applying the iris-texture
1. From the totalTextures 4 CD copy the "heye007_psd.psd"-texture onto your desktop
2. Make a New Material (in the file-menu in the lower left side of the screen) and double click its icon in the Material Manager. In the Material Editor, change its name from "Mat" to "eye" .
3. Go to the Color channel. It is already activated. Click the ...-button, locate the iris-texture on your desktop and click Open. The texture is now loaded into the Color channel and its icon in the Material Manager is showing a thumbnail of the texture
4. Close the Material Editor
5. Drag the "eye"-material on top of the "inside eye"-object in the Object Manager. What you see there has something spiderish, doesn't it?
6. Next to the "inside eye"-object is a new, small Texture Tag that shows the iris-texture. In the Attribute Manager, change Projection from UVW Mapping to Flat. The projection is udated immediately and shows the iris placed upon the eye-object almost perfectly
6. Almost, because when you go to Camera > Right you can see the texture has also been applied to the back of the eye. Hit Render > Render View to see it better. Go back to Perspective (Camera > Perspective), hit the h-key to frame the scene in the viewport and you'll also see that the hole for the pupil is too big for the pupil in the texture. We'll do something about the pupil first
Tweaking the pupil shape to fit the texture
1. Zoom in and rotate the view until you have the edge of the pupil filling the viewport.
2. Choose Selection > Loop Selection, drag over the edge polygons until they're highlighted yellow and click.
3. We'll create some new polygons to fit the texture better: Select the Extrude Selected -tool and make sure "create caps" is inactive. Drag in the viewport and see a new ring of polygons being born. Continue until you can see the first bit of the pupil in the iris-texture appearing on the new polygons.
Attaching the texture to the polygons and making the pupil reflex work
1. With the inside pupil edge polygons selected, choose Selection > Grow Selection or hit u~y
2. From the Object Manager > File menu select Cinema 4D Tags > Stick Texture. A Stick Texture Tag is created next to the "inside eye"-object
3. Now choose the Scale Tool, place the cursor somewhere in the viewport and drag from right to left and back to see the pupil reflex in working. Beautiful.
4. In the Selection menu, choose Set Selection. A selection tag is created for the object. Click it, and in the Attributes Manager, rename it "reflex"
Solving the double texture projection
1. Switch to Camera > Right. Select the Rectangle Selection tool. Make sure Only Select Visible Elements is switched off and drag around the polies of the front of the eye as shown
2. In order not to overwrite the Selection Tag we've just made with the one that we are going to make now, click the blue triangle of the "inside eye"-model.
3. Go to Selection > Set Selection. A second Selection Tag is added to the model. Click on it in order to select its Attributes
4. In the Name box rename the tag to "front".
5. Next, select the Texture Tag and drag the rightmost Selection Tag (the one that is called "front") to the Selection box in the Attributes Manager. Immediately the portion of texture that was projected onto the back of the eye is removed
Making the cornea
1. Select the outside eye object. Unhide it from the viewport and the renderer by clicking on the small red dots next to it until they turn grey. There are still polygons selected but we need none selected. So, In Selection, choose Deselect All
2. Select the Polygon Tool to go into polygon mode if not already selected.
3. Select Extrude Selected and in the Attributes Manager type "3" in the Offset box. Make sure Create Caps is switched back on. Click Apply.
4. When you hit the render button now, you can see the eye is encapsulated by the cornea but it is grey and opaque. We need to make a glassy texture.
Making and applying the cornea texture
1. In the Material Manager, select File > New Material. Double-click the new material thumbnail (next to our iris material).
2. In the Material Editor, activate the Transparancy channel. Set Brightness to 90%. In the Refraction box, type 1,33 and activate Fresnel
3. Activate the Reflection channel and leave Brightness to 100%
4. Rename the Material "cornea"
5. Close the Material editor
6. Drag the cornea texture to the "outside eye"-object
A final small tweak
1. Now, when you hit the render button, it doesn't look quite right. That is because the polygons of the inside of the cornea are in the exact same location as the outside polygons of the eye. We need to ever so slightly change the size of the cornea
2. Select the Model Tool. In the XYZ-Scale, change size to Scale. Change the input from 1 to 0.999 in all three dimensions and hit Enter or Return. Now, when you render, everything should look just fine.
3. Select the "inside eye"-object in the Object Manager. Click the Polygon Tool to go into polygon mode. Next, click the Selection Tag for the pupil reflex (the leftmost one) and in the Attributes Manager, click Restore Selection. With the Scale Tool you can now change the diameter of the pupil.