1al_draw_filled_polygon_with_holes(3)      al_draw_filled_polygon_with_holes(3)
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NAME

6       al_draw_filled_polygon_with_holes - Allegro 5 API
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SYNOPSIS

9              #include <allegro5/allegro_primitives.h>
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11              void al_draw_filled_polygon_with_holes(const float *vertices,
12                 const int *vertex_counts, ALLEGRO_COLOR color)
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DESCRIPTION

15       Draws  a  filled simple polygon with zero or more other simple polygons
16       subtracted from it - the holes.  The holes cannot  touch  or  intersect
17       with the outline of the filled polygon.
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19       • vertices - Interleaved array of (x, y) vertex coordinates for each of
20         the polygons, including holes.
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22       • vertex_counts - Number of vertices for each polygon.  The  number  of
23         vertices  in the filled polygon is given by vertex_counts[0] and must
24         be at least three.  Subsequent elements indicate the number  of  ver‐
25         tices  in  each  hole.   The array must be terminated with an element
26         with value zero.
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28       • color - Color of the filled polygon
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30       When the y-axis is facing downwards (the usual) the filled polygon  co‐
31       ordinates  must  be ordered anti-clockwise.  All hole vertices must use
32       the opposite order (clockwise with y down).  All hole vertices must  be
33       inside the main polygon and no hole may overlap the main polygon.
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35       For example:
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37              float vertices[] = {
38                    0,   0, // filled polygon, upper left corner
39                    0, 100, // filled polygon, lower left corner
40                  100, 100, // filled polygon, lower right corner
41                  100,   0, // filled polygon, upper right corner
42                   10,  10, // hole, upper left
43                   90,  10, // hole, upper right
44                   90,  90  // hole, lower right
45              };
46              int vertex_counts[] = {
47                 4, // number of vertices for filled polygon
48                 3, // number of vertices for hole
49                 0  // terminator
50              };
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52       There  are  7  vertices:  four for an outer square from (0, 0) to (100,
53       100) in anti-clockwise order, and three more for an inner  triangle  in
54       clockwise  order.   The outer main polygon uses vertices 0 to 3 (inclu‐
55       sive) and the hole uses vertices 4 to 6 (inclusive).
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SINCE

58       5.1.0
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SEE ALSO

61       al_draw_filled_polygon(3),        al_draw_filled_polygon_with_holes(3),
62       al_triangulate_polygon(3)
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66Allegro reference manual                  al_draw_filled_polygon_with_holes(3)
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