![]() |
![]() |
![]() |
Goffice Reference Manual | ![]() |
---|---|---|---|---|
#include <goffice/graph/go-geometry.h> #define GO_GEOMETRY_ANGLE_TOLERANCE enum GOGeometrySide; enum GOGeometryRotationType; GOGeometryOBR; #define GOGeometryAABR void go_geometry_cartesian_to_polar (double x, double y, double *rho, double *theta); double go_geometry_point_to_segment (double xp, double yp, double xs, double ys, double w, double h); void go_geometry_AABR_add (GOGeometryAABR *aabr0, GOGeometryAABR const *aabr1); void go_geometry_OBR_to_AABR (GOGeometryOBR const *obr, GOGeometryAABR *aabr); gboolean go_geometry_test_OBR_overlap (GOGeometryOBR const *obr0, GOGeometryOBR const *obr1); GOGeometryRotationType go_geometry_get_rotation_type (double alpha); GOGeometrySide go_geometry_calc_label_position (GOGeometryOBR *obr, double alpha, double offset, GOGeometrySide side, GOGeometrySide anchor); GOGeometrySide go_geometry_calc_label_anchor (GOGeometryOBR *obr, double alpha);
typedef enum { GO_SIDE_LEFT = 1 << 0, GO_SIDE_RIGHT = 1 << 1, GO_SIDE_LEFT_RIGHT = 3 << 0, GO_SIDE_TOP = 1 << 2, GO_SIDE_BOTTOM = 1 << 3, GO_SIDE_TOP_BOTTOM = 3 << 2, GO_SIDE_AUTO = 15 } GOGeometrySide;
typedef enum { GO_ROTATE_NONE = 0, GO_ROTATE_COUNTERCLOCKWISE = 1, GO_ROTATE_UPSIDEDOWN = 2, GO_ROTATE_CLOCKWISE = 3, GO_ROTATE_FREE = 4 } GOGeometryRotationType;
typedef struct { double x,y; /* Center */ double w,h; /* Edges */ double alpha; /* Angle from x axis to w edge, in radians */ } GOGeometryOBR;
void go_geometry_cartesian_to_polar (double x, double y, double *rho, double *theta);
Converts cartesion coordinates to polar coordinates.
|
cartesian coordinate |
|
cartesian coordinate |
|
polar coordinate |
|
polar coordinate |
double go_geometry_point_to_segment (double xp, double yp, double xs, double ys, double w, double h);
Computes the distance between a point and a segment.
|
point coordinate |
|
point coordinate |
|
segment start coordinate |
|
segment start coordinate |
|
extent of segment |
|
extent of segment |
Returns : |
void go_geometry_AABR_add (GOGeometryAABR *aabr0, GOGeometryAABR const *aabr1);
Computes the Axis Aligned Bounding Rectangle of aabr0 and aabr1, and stores result in aabr0.
|
a GOGeometryAABR |
|
a GOGeometryAABR |
void go_geometry_OBR_to_AABR (GOGeometryOBR const *obr, GOGeometryAABR *aabr);
Stores Axis Aligned Bouding Rectangle of obr
in aabr
.
|
a GOGeometryOBR |
|
a GOGeometryAABR |
gboolean go_geometry_test_OBR_overlap (GOGeometryOBR const *obr0, GOGeometryOBR const *obr1);
Overlap test of Oriented Bounding Rectangles by the separating axis method.
|
a GOGeometryOBR |
|
a GOGeometryOBR |
Returns : |
TRUE if OOBRs overlap
|
GOGeometryRotationType go_geometry_get_rotation_type (double alpha);
Calculates rotation type for handling of special angles (alpha = n * pi / 2)
|
angle in radians |
Returns : |
a GOGeometryRotationType |
GOGeometrySide go_geometry_calc_label_position (GOGeometryOBR *obr, double alpha, double offset, GOGeometrySide side, GOGeometrySide anchor);
Convenience routine that computes position of a label relative to an axis.
|
bounding rectangle of label |
|
angle of axis |
|
minimum distance between label and axis |
|
side of label with respect to axis |
|
where to anchor the label |
Returns : |
the computed anchor if anchor == GO_SIDE_AUTO, or anchor value.
|
GOGeometrySide go_geometry_calc_label_anchor (GOGeometryOBR *obr, double alpha);
|
bounding rectangle of label |
|
angle of axis |
Returns : |
computed label anchor, to be used by go_geometry_calc_label_position. |