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8.5 Rendering Project I: Drop Shadow and Punchout

To illustrate some of the techniques discussed in this chapter, let's apply them to a project using the image shown in Figure 8.23(a).

Figure 8.23: Original Image and Color Corrected Selection of Astronaut

The astronaut in this image is selected from its background using various methods from Chapters 3 and 4. After the selection, methods described in Section 6.1 are used to improve the tonal range, and the result is shown in Figure 8.23(b).

This project uses a drop shadow and a punchout to create a composition with our astronaut. The goal is to create the effect that he has extracted himself from the 2D plane and is wandering off on his own. To start, the selected astronaut is placed over a blue-gray layer. The result of this is shown in Figure 8.24(a),

Figure 8.24: Making a Gray-Blue Background Layer and Creating a Channel Mask from the Astronaut's Alpha Channel

and the associated Layers dialog is shown in Figure 8.24(b).

The most important element of the project is the outline of the astronaut because this is used to create both the shadow and the punchout effects. Thus, the next step is to save the outline as a channel mask. This is done by making the Astronaut layer active, applying the `Alpha to Selection` function found in the Layers menu, and then using `Save to Channel` from the `Image:Select` menu. This creates the channel mask shown in Figure 8.24(c). After the save-to-channel operation, it is important to cancel the selection by typing `C-S-a` in the image window.

The punchout is made first. This is begun by copying the astronaut mask and pasting it into a new layer. This new layer, labeled Punchout, is positioned between the Blue Gray Background layer and the Astronaut layer as shown in Figure 8.25(a).

Figure 8.25: Starting the Punchout

To create the punchout, this new layer is copied into its own layer mask as shown in Figure 8.25(b).

All that remains to finish the punchout effect is to blur the image in the Punchout layer and to offset it. Figure 8.26(a)

Figure 8.26: Finishing the Punchout

shows that a value of 20 is chosen in the `Gaussian Blur (IIR)` dialog, and Figure 8.26(b) shows that values of 8 and 4 have been chosen in the `Offset` dialog. The result is shown in Figure 8.26(c). Note that, for the punchout to be seen in Figure 8.26(c), the visibility of the Astronaut layer has been toggled off, as shown in Figure 8.26(d).

Before moving to the next stage of the project, let's give the punchout a bit more pizzazz by inserting an interesting image pattern. To do this, the Punchout layer is duplicated by first clicking on its thumbnail in the Layers dialog, and then clicking on the Duplicate Layer button. This creates a layer called Punchout Copy just above the original. The image part of the Punchout layer is made active by clicking on its thumbnail. This layer is now filled with the pink marble pattern from the `Pattern Selection` dialog (see Figure 8.27(c)). This is done using the `Bucket Fill` tool, where the fill type is set to Pattern Fill and the Threshold is set to 255. Finally, the Mode menu for the Punchout Copy layer is set to `Multiply`, as shown in Figure 8.27(b).

Figure 8.27: Jazzing up the Punchout with a Pattern Image Background

This produces the result shown in Figure 8.27(a), which makes it appear as if the wall behind the Background layer is made of pink marble.

The final step of this project is to rotate the astronaut, reposition him, and give him a drop shadow. To do this, he is first made visible by clicking on the Eye icon of the Astronaut layer in the Layers dialog. The rest is detailed in the following steps:

1.
  Rotate the astronaut using the `Transform` tool.
2.
  Move the astronaut to a new position using the `Move` tool.
3.
  Duplicate the Astronaut layer, creating a layer labeled Astronaut Copy.
4.
  Set the threshold of the `Bucket Fill` tool to 255 and use it to fill the Astronaut layer with black.
5.
  Blur the Astronaut layer with `Gaussian Blur (IIR)`.
6.
  Offset the Astronaut layer an appropriate amount.

The final result is shown in Figure 8.28(a).

Figure 8.28: The Final Rendered Image

The resulting Layers dialog is shown in Figure 8.28(b).

Next: 8.6 Rendering Project II: Up: 8. Rendering Techniques Previous: 8.4 Shadows
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