Prima::Drawable::Gradient(3pm)

1Prima::Drawable::GradieUnste(r3)Contributed Perl DocumenPtraitmiao:n:Drawable::Gradient(3)
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NAME

6       Prima::Drawable::Gradient - gradient fills for primitives
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DESCRIPTION

9       Prima offers primitive gradient services to draw gradually changing
10       colors.  A gradient is requested by setting of at least two colors and
11       optionally a set of quadratic spline points that, when, projected,
12       generate the transition curve between the colors.
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14       The module augments the "Prima::Drawable" drawing functionality by
15       adding "new_gradient" function.
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SYNOPSIS

18               $canvas-> new_gradient(
19                       palette => [ cl::White, cl::Blue, cl::White ],
20               )-> sector(50,50,100,100,0,360);
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API

23   Methods
24       new $CANVAS, %OPTIONS
25           Here are %OPTIONS understood in the gradient request:
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27           clone %OPTIONS
28               Creates a new gradient object with %OPTIONS replaced.
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30           widgetClass INTEGER
31               Points to a widget class to resolve generic colors like
32               "cl::Back", that may differ from widget class to widget class.
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34           palette @COLORS
35               Each color is a "cl::" value. The gradient is calculated as
36               polyline where each its vertex corresponds to a certain blend
37               between two neighbouring colors in the palette. F.ex. the
38               simplest palette going from "cl::White" to "cl::Black" over a
39               polyline 0..1 (default), produces pure white color at the start
40               and pure black color at the end, filling all available shades
41               of gray in between, and changing monotonically.
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43           poly @VERTICES
44               Set of 2-integer polyline vertexes where the first integer is a
45               coordinate (x, y, or whatever required by the drawing
46               primitive) between 0 and 1, and the second is the color blend
47               value between 0 and 1.
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49               Default: ((0,0),(1,1))
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51           spline \@VERTICES, %OPTIONS
52               Serving same purpose as "poly" but vertexes are projected first
53               to a B-spline curve using render_spline and %OPTIONS. The
54               resulting polyline is treated as "poly".
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56           vertical BOOLEAN
57               Only used in bar, to set gradient direction.
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59           See also: bar, stripes .
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61       bar X1, Y1, X2, Y2, VERTICAL = 0
62           Draws a filled rectangle within (X1,Y1) - (X2,Y2) extents
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64           Context used: fillPattern, rop, rop2
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66       colors BREADTH
67           Returns a list of gradient colors for each step from 1 to BREADTH.
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69       ellipse X, Y, DIAM_X, DIAM_Y
70           Draws a filled ellipse with center in (X,Y) and diameters
71           (DIAM_X,DIAM_Y)
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73           Context used: fillPattern, rop, rop2
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75       sector X, Y, DIAM_X, DIAM_Y, START_ANGLE, END_ANGLE
76           Draws a filled sector with center in (X,Y) and diameters
77           (DIAM_X,DIAM_Y) from START_ANGLE to END_ANGLE
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79           Context used: fillPattern, rop, rop2
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81       stripes BREADTH
82           Returns an array consisting of integer pairs, where the first one
83           is a color value, and the second is the breadth of the color strip.
84           bar uses this information to draw a gradient fill, where each color
85           strip is drawn with its own color. Can be used for implementing
86           other gradient-aware primitives (see examples/f_fill.pl )
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AUTHOR

89       Dmitry Karasik, <dmitry@karasik.eu.org>.
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NAME

DESCRIPTION

SYNOPSIS

API

AUTHOR

SEE ALSO