Two-dimensional (2D) graphic design commonly lacks the depth, the photorealistic lighting effects, and the perspective perception that the human eye expects when viewing objects in a real world environment.

True three-dimensional (3D) graphic design can fill this gap. However, a true 3D design is often expensive and slow. 3D software is difficult to learn and use. And it requires a great deal of computer resources and time to correctly approximate typical real world effects. Graphic designers without prior knowledge of vector geometry and concepts of camera viewing model will have a very hard time visualizing 3D modeling and rendering techniques.

Even though 2D applications such as Photoshop and Gimp has no true 3D capacity, it provides many effects and transformation mechanisms to approximate and simulate the 3D depth and lighting effects with often strikingly accurate results. The approximation may exhibit obvious errors to a 3D purist, especially in the reproduction of lighting effects such as soft shadows and reflection. However, in a 2D environment, a simulated 3D design has its own merit as artwork and can effectively deliver the designer's message with standard 2D design tools.

The concepts of the following effects illustrated in subsequent pages can be combined to simulate a particular 3D setting. By observing and analyzing the obvious lighting features in a typical 3D scene, a designer can use one or more of these effects to reproduce and empahize the obvious features and omit the non-essential ones.

The results are often dramatic in many cases.

Variation 4: Text with drop shadows.
Drop shadows instantly separate the background from the foreground text object. This effect adds the perception of depth to your two-dimensional shape or text design. The illusion of depth can be enhanced by moving the shadow farther away from the object which is casting it. Additional filters can also be used to create more sophisticated design of soft shadows such as casting subtle hues to the drop shadow based upon the surrounding text color.

The sharpness of the shadow creates the illusion of how far away the light source is from the object. A crisp shadow indicates a close-by light source. Light sources which are further away cast a much softer shadow. You should experiment with the direction of light (the angle at which the light source is located) to make your design more realistic. The distance from the object to its shadow gives the illusion of how close the object to the background having the shadow cast.

The shadow can be placed behind its object using the Cartesian coordinate model by supplying a horizontal and vertical offset amount, measured from the center of the object to the center of its shadow. This model is user-friendly in the sense that most users will specify the same distance for both offsets and quickly achieves good result. This effectively places the light source at the upper left (northwest) corner of the picture, (approximately 135 degrees measured counterclockwise from the 3-o'clock position).

The shadow position can be computed accurately with the Polar coordinate model by supplying two values. One, a distance vector to indicate how far the center of the shadow is from the center of its object. This is equivalent to the radius of the polar coordinate circle. And two, a direction angle to indicate where the light source is (its exact location on the polar circle). The 2D application then computes the correct vertical and horizontal offset.

Distance:
Angle:
X Offset:
Y Offset:
The above illustration converts measurements between these two popular models for the accurate positioning of drop shadows. Click and drag anywhere on the above round button icon to position the drop shadow. On Firefox or non-Internet Explorer browser, click and drag momentarily, and release the mouse button while moving to position the shadow. X-Offset and Y-Offset refer to the horizontal and vertical offset amounts, respectively, measured in the Cartesian coordinate model.