Material and Illumination - Essentials of Interactive Computer Graphics - page 469

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Material and Illumination

In this appendix, we demonstrate how to work with the default illumination model
implemented in all of today's graphics hardware. This model is known as the
Phong illumination model. An illumination model computes a pixel color based
on the visible geometry and the lighting conditions of the scene. Typically, input
to an illumination mode includes:

• Object geometry. Describes the shape of the geometry. This information
is typically defined as a normal vector at each vertex.

• Material property. Describes the appearance of the visible object (e.g.,
how incoming light is reflected).

• Scene lighting conditions. Describes the light sources that illuminate the
scene.

In a traditional computer graphics textbook, the Phong illumination model and
the associated lighting computation are typically covered extensively in dedicated
chapters. With the recent advancements in graphics hardware technology, the
future of a pre-defined default illumination model across all hardware platforms
is becoming uncertain. This appendix includes examples that demonstrate how to
work with the existing graphics hardware without in-depth discussions.

Figure A.1. Tutorial

A.1.

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