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Why specular component of the Phong model is white?
Visual illustration of the Phong equation: here the light is white, the ambient and diffuse colors are both blue, and the specular color is white, reflecting a small part of the light hitting the surface, but only in very narrow highlights.
Why do we use exponential terms in Phong illumination equation?
The clever thing about Phong’s equation was that it gave a neat way to calculate the specular intensity ‘bump’ around the light reflection vector (R). The larger the exponential power (n) the smaller and more intense the specular intensity bump. Hence specular highlights.
What is specular in terms of rendering?
In computer graphics, it means the quantity used in three-dimensional (3D) rendering which represents the amount of reflectivity a surface has. It is a key component in determining the brightness of specular highlights, along with shininess to determine the size of the highlights.
How is the Phong of a specular highlight multiplied?
The Phong term is multiplied by the light intensity in the lighting equation. The brightness of the specular highlight for a particular viewing direction is based on raising the cosine of the angle between the view direction and the reflection direction to a power.
What does the specular exponent of Phong mean?
The specular exponent can range from (0, ∞). A small exponent makes for a rougher appearance, while a large exponent suggests a shiny surface. The Phong term computed above is then multiplied with the light intensity. This represents the maximum light reflected along the view direction.
When to include specular term in Phong reflection model?
Although the above formulation is the common way of presenting the Phong reflection model, each term should only be included if the term’s dot product is positive. (Additionally, the specular term should only be included if the dot product of the diffuse term is positive.) for the different color channels .
Which is an illustration of the Phong equation?
Visual illustration of the Phong equation: here the light is white, the ambient and diffuse colors are both blue, and the specular color is white, reflecting a small part of the light hitting the surface, but only in very narrow highlights.