Among the most complex of Photoshop's filters is 3D Transform. Found with the Render filters, it is used to manipulate a selection to make it appear to be wrapped around a cylinder, ball, or cube. Until you're familiar with the controls, using the filter can be a frustrating experience.
The 3D Transform filter will apply its effect to an active layer or to a selection. For this explanation, we'll look at working with the entire contents of a layer. (The bottle is PhotoSpin image #0150003.)
After selecting the menu command Filter> Render> 3D Transform, the dialog box appears, showing you a small preview window depicting your selection. There are four basic steps to applying the filter:
- Setting the 3D object.
- Editing the 3D object.
- Manipulating the selection.
- Adjusting the camera (view).
Select one of the three basic 3D shapes. Drag with the appropriate tool to delineate the dimensions of the 3D surface around which the selection will be wrapped. The 3D object will appear as a wireframe.
The Selection Tool (black arrow, keyboard shortcut V) can be used to reposition the 3D wireframe. The Direct Selection Tool (white arrow, keyboard shortcut A) can be used to alter the basic shape of the wireframe. There are specific points, called vertex points, on each of the three wireframes that can be manipulated. They are hollow square points along the paths of the 3D object. They are shown here marked by red dots.
The lower vertex point on the cylinder and cube can be used to tip the "object" up or down. If you try to create an object that couldn't exist in nature, the wireframe will turn red and you'll not be able to execute the filter.
The Add Anchor Point Tool and Delete Anchor Point Tool can be used to add and subtract additional points from the wireframe. (The Delete Anchor Point Tool cannot be used on the existing vertex points, only on round or diamond-shaped anchor points.) The 3D Transform dialog box's tools also include the Convert Anchor Point Tool for changing anchor points from smooth to corner (and from corner to smooth), and a Hand and Zoom tool to change your view in the Preview window.
The goal is to create the object as it would appear when oriented to match the selection as it is now. It this case, we want to create a bottle shape that is perfectly horizontal to the point of view. In other words, the label we have created, which we want to match the bottle as it exists in the image, is straight in the image.
Therefore, we want to create a wireframe of the bottle that is also straight. While it is only necessary to create that part of the object that is the size and shape of the selection, we'll work with a wireframe that represents the majority of the bottle.
Once the 3D wireframe's shape represents the surface around which you want to bend your selection, it's time to make the selection become "3D." The Trackball Tool is used to manipulate the "object" and the selection in three dimensions. Now we want the label and the wireframe to match the orientation of the bottle in the image.
The Pan Camera tool is used to reposition within the window. (Remember that the 3D manipulation (Trackball Tool) and the movement within the window (Pan Camera Tool) affect only the selection, not anything on other layers (or outside the selection) in the image.)
Keep in mind that any part of the "back" of the 3D object (or top or bottom) that appears in the preview window will be created as a grayscale object in your image. (If unwanted, it can be selected and deleted. It will appear on the active layer. This is one of the reasons that I suggest making a copy of the layer or selection before using the 3D Transform command.)
Once we've got the wireframe and selection positioned, we can use the controls on the right side of the dialog box to adjust the final appearance. The Field of View slider ranges from 1 degree to 130 degrees. It represents the "camera lens."
The Dolly slider zooms the view in and out. It can go from 1 to 99.
The Options button allows you to choose low, medium, or high resolution, as well as low, medium, high, or None for anti-aliasing. You can also choose to hide or display the background in the preview window. Be aware that higher quality rendering and anti-aliasing add considerable time to the application of the filter.
When it all looks just right, click the OK button. After the filter is applied, matching highlights and shading will add realism to the image.
Because you cannot see the entire image in the preview window, exactly matching a background, such as this bottle, can be difficult. However, with some practice, and an understanding of how the 3D Transform filter works, it can be used efficiently to manipulate a selection in simulated 3D.