Set the Colour field to define the colour of the light source. The colour is defined as an array of four 32-bit floating point values between 0 and 1.0. The array elements consist of Red, Green, Blue and Alpha values in that order.

If the algorithm supports it, the Alpha component defines the intensity of the light source.

The default colour is pure white, 1.0,1.0,1.0,1.0.

In the Phong lighting model, this field specifies the kd value in diffuse mode, or ks value in specular mode.

This field defines the exponent value for specular lighting, within a range of 1.0 to 128.0. The larger the value, shinier the end result.

Indicates the intended distance in current filter units (i.e. as determined by the value of PrimitiveUnits) for dx in the surface normal calculation formulas.

By specifying value(s) for UnitX, the kernel becomes defined in a scalable, abstract coordinate system. If UnitX is not specified, the default value is one pixel in the offscreen bitmap, which is a pixel-based coordinate system, and thus potentially not scalable. For some level of consistency across display media and user agents, it is necessary that a value be provided for at least one of ResX and UnitX.

Indicates the intended distance in current filter units (i.e. as determined by the value of PrimitiveUnits) for dy in the surface normal calculation formulas.

By specifying value(s) for UnitY, the kernel becomes defined in a scalable, abstract coordinate system. If UnitY is not specified, the default value is one pixel in the offscreen bitmap, which is a pixel-based coordinate system, and thus potentially not scalable. For some level of consistency across display media and user agents, it is necessary that a value be provided for at least one of ResY and UnitY.