1 #ifndef __NR_FILTER_PRIMITIVE_H__
2 #define __NR_FILTER_PRIMITIVE_H__
4 /*
5 * SVG filters rendering
6 *
7 * Author:
8 * Niko Kiirala <niko@kiirala.com>
9 *
10 * Copyright (C) 2006 Niko Kiirala
11 *
12 * Released under GNU GPL, read the file 'COPYING' for more information
13 */
15 #include "display/nr-filter-slot.h"
16 #include "libnr/nr-pixblock.h"
17 #include "libnr/nr-matrix.h"
18 #include "svg/svg-length.h"
20 namespace NR {
22 class FilterPrimitive {
23 public:
24 FilterPrimitive();
25 virtual ~FilterPrimitive();
27 int render(FilterSlot &slot, NRMatrix const *trans);
28 virtual int render(FilterSlot &slot, Matrix const &trans) = 0;
29 virtual int get_enlarge(Matrix const &m);
31 /**
32 * Sets the input slot number 'slot' to be used as input in rendering
33 * filter primitive 'primitive'
34 * For filter primitive types accepting more than one input, this sets the
35 * first input.
36 * If any of the required input slots is not set, the output of previous
37 * filter primitive is used, or SourceGraphic if this is the first
38 * primitive for this filter.
39 */
40 virtual void set_input(int slot);
42 /**
43 * Sets the input slot number 'slot' to be user as input number 'input' in
44 * rendering filter primitive 'primitive'
45 * First input for a filter primitive is number 0. For primitives with
46 * attributes 'in' and 'in2', these are numbered 0 and 1, respectively.
47 * If any of required input slots for a filter is not set, the output of
48 * previous filter primitive is used, or SourceGraphic if this is the first
49 * filter primitive for this filter.
50 */
51 virtual void set_input(int input, int slot);
53 /**
54 * Sets the slot number 'slot' to be used as output from filter primitive
55 * 'primitive'
56 * If output slot for a filter element is not set, one of the unused image
57 * slots is used.
58 * It is an error to specify a pre-defined slot as 'slot'. Such call does
59 * not have any effect to the state of filter or its primitives.
60 */
61 virtual void set_output(int slot);
63 void set_x(SVGLength &length);
64 void set_y(SVGLength &length);
65 void set_width(SVGLength &length);
66 void set_height(SVGLength &length);
68 /**
69 * Sets the filter primitive subregion. Passing an unset length
70 * (length._set == false) as any parameter results in that parameter
71 * not being changed.
72 * Filter primitive will not hold any references to the passed
73 * SVGLength object after function returns.
74 * If any of the parameters does not get set the default value, as
75 * defined in SVG standard, for that parameter is used instead.
76 */
77 void set_region(SVGLength &x, SVGLength &y,
78 SVGLength &width, SVGLength &height);
80 /**
81 * Resets the filter primitive subregion to its default value
82 */
83 void reset_region();
85 protected:
86 int _input;
87 int _output;
89 SVGLength _region_x;
90 SVGLength _region_y;
91 SVGLength _region_width;
92 SVGLength _region_height;
93 };
96 } /* namespace NR */
101 #endif /* __NR_FILTER_PRIMITIVE_H__ */
102 /*
103 Local Variables:
104 mode:c++
105 c-file-style:"stroustrup"
106 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
107 indent-tabs-mode:nil
108 fill-column:99
109 End:
110 */
111 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :