2.1.1798 Part 4 Section 184.108.40.206, shadow (Shadow Effect)
a. The standard states that the values of the type attribute are defined by the ST_ShadowType simple type and some additional values.
Office only allows the values defined in the ST_ShadowType simple type for this attribute.
b. The standard does not specify bounds for the matrix attribute.
In Office, these numeric values may be specified in 1/65536-ths if a trailing "f" is supplied. [Example: A value of "52429f" represents 52429/65536, or 0.8. end example] The minimum and maximum values for are -2147483644f to 2147483647f.
c. The standard does not indicate how the matrix attribute is applied to the shadow.
Office applies this matrix to a point in the following way.
Let be a point in the object (after rotation, if the shape is rotated) described by .
Let and .
A new point is calculated as .
In Office, if and then .
The origin for the coordinate system used here is defined by the origin attribute, which is dependent on the height and width of the shape.
d. The standard indicates that drawingRelative and shapeRelative are valid simple type values for the type attribute.
If the value of the type attribute is drawingRelative or shapeRelative, Office transforms the shadow to use a value of perspective on file save.
e. The standard indicates that emboss is a valid simple type values for the type attribute.
If the value of the type attribute is emboss and the offset or offset2 attribute is defined using fractional values of the shape dimensions, Office transforms the shadow to use a value of perspective on file save.
f. The standard indicates how the obscured attribute is used.
In Office, if the value of the obscured attribute is false, then the shadow is transparent if there is no fill on the shape.
g. The standard indicates that the default value for the on attribute is true.
In Office, if the on attribute value is blank, it is considered to be true. If it is absent, it defaults to false.
h. The standard does not restrict the number of instances of this element.
Office allows at most only one instance of the shadow element in each place where it can be used.
i. The standard states that values of the opacity attribute are defined by the XML Schema string datatype.
Office defines the values of the opacity attribute with the ST_Fraction (§3.9.1, ST_Fraction) simple type.