al_draw_polyline - Allegro 5 API
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#include <allegro5/allegro_primitives.h>
void al_draw_polyline(const float* vertices, int vertex_stride,
int vertex_count, int join_style, int cap_style,
ALLEGRO_COLOR color, float thickness, float miter_limit)
Draw a series of line segments.
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- vertices - Interleaved array of (x, y) vertex coordinates
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- vertex_stride - the number of bytes between pairs of vertices (the
stride)
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- vertex_count - Number of vertices in the array
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- join_style - Member of ALLEGRO_LINE_JOIN(3) specifying how to render the
joins between line segments
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- cap_style - Member of ALLEGRO_LINE_CAP(3) specifying how to render the end
caps
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- color - Color of the line
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- thickness - Thickness of the line, pass <= 0 to draw hairline
lines
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- miter_limit - Parameter for miter join style
The stride is normally 2 * sizeof(float) but may be more if the
vertex coordinates are in an array of some structure type, e.g.
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struct VertexInfo {
float x;
float y;
int id;
};
void my_draw(struct VertexInfo verts[], int vertex_count, ALLEGRO_COLOR c)
{
al_draw_polyline((float *)verts, sizeof(VertexInfo), vertex_count,
ALLEGRO_LINE_JOIN_NONE, ALLEGRO_LINE_CAP_NONE, c, 1.0, 1.0);
}
The stride may also be negative if the vertices are stored in
reverse order.
al_draw_polygon(3), ALLEGRO_LINE_JOIN(3), ALLEGRO_LINE_CAP(3)