CHAPTER 4
314
Graphics
11 0 obj
<< /FunctionType 2
/Domain [ 0.0 1.0 ]
/C0 [ 0.929 0.357 1.000 0.298 ]
/C1 [ 0.631 0.278 1.000 0.027 ]
/N 1.048
>>
endobj
12 0 obj
<< /FunctionType 2
/Domain [ 0.0 1.0 ]
/C0 [ 0.929 0.357 1.000 0.298 ]
/C1 [ 0.941 0.400 1.000 0.102 ]
/N 1.374
>>
endobj
Example 4.26
% First subfunction
% Second subfunction
316.789 140.311 m
% Move to start of leaf
303.222 146.388 282.966 136.518 279.122 121.983 c
% Curved segment
277.322 120.182 l
% Straight line
285.125 122.688 291.441 121.716 298.156 119.386 c
% Curved segment
336.448 119.386 l
% Straight line
331.072 128.643 323.346 137.376 316.789 140.311 c
% Curved segment
W n
% Set clipping path
q
% Save graphics state
27.7843 0.0000 0.0000
−27.7843
310.2461 121.1521 cm
% Set matrix
/Sh1 sh
% Paint shading
Q
% Restore graphics state
Type 4 Shadings (Free-Form Gouraud-Shaded Triangle Meshes)
Type 4 shadings (free-form Gouraud-shaded triangle meshes) are commonly
used to represent complex colored and shaded three-dimensional shapes. The
area to be shaded is defined by a path composed entirely of triangles. The color at
each vertex of the triangles is specified, and a technique known as
Gouraud
interpolation
is used to color the interiors. The interpolation functions defining
the shading may be linear or nonlinear. Table 4.32 shows the entries specific to
this type of shading dictionary, in addition to those common to all shading dic-
tionaries (Table 4.28) and stream dictionaries (Table 3.4 on page 62).