New SQL functions supporting Circles and Ellipses introduced in 4.1.0
MakeCircle ( cx, cy, radius ) MakeCircle ( cx, cy, radius, srid ) MakeCircle ( cx, cy, radius, srid, step ) Will return a closed Linestring approximating a circle.
| ![]() SELECT MakeCircle(0, 0, 100, -1, 1); | |
MakeEllipse ( cx, cy, x_axis, y_axis ) MakeEllipse ( cx, cy, x_axis, y_axis, srid ) MakeEllipse ( cx, cy, x_axis, y_axis, srid, step ) Will return a closed Linestring approximating an ellipse.
| ![]() SELECT MakeEllipse(0, 0, 100, 50, -1, 1); |
![]() SELECT MakeEllipse(0, 0, 50, 100, -1, 1); |
MakeArc ( cx, cy, radius, start, stop ) MakeArc ( cx, cy, radius, start, stop, srid ) MakeArc ( cx, cy, radius, start, stop, srid, step ) Will return a Linestring approximating a circular arc.
| ![]() SELECT MakeArc(0, 0, 100, 30, 150, -1, 1); |
![]() SELECT MakeArc(0, 0, 100, 30, 150, -1, 1); |
MakeEllipticArc ( cx, cy, x_axis, y_axis, start, stop ) MakeEllipticArc ( cx, cy, x_axis, y_axis, start, stop, srid ) MakeEllipticArc ( cx, cy, x_axis, y_axis, start, stop, srid, step ) Will return a Linestring approximating an elliptic arc. | ![]() SELECT MakeEllipticArc(0, 0, 50, 100, 30, 150, -1, 1); |
![]() SELECT MakeEllipticArc(0, 0, 50, 100, 150, 30, -1, 1); |
MakeCircularSector ( cx, cy, radius, start, stop ) MakeCircularSector ( cx, cy, radius, start, stop, srid ) MakeCircularSector ( cx, cy, radius, start, stop, srid, step ) Will return a Polygon approximating a circular sector. | ![]() SELECT MakeCircularSector(0, 0, 100, 330, 30, -1, 1); |
![]() SELECT MakeCircularSector(0, 0, 100, 30, 330, -1, 1); |
MakeEllipticSector ( cx, cy, x_axis, y_axis, start, stop ) MakeEllipticSector ( cx, cy, x_axis, y_axis, start, stop, srid ) MakeEllipticSector ( cx, cy, x_axis, y_axis, start, stop, srid, step ) Will return a Polygon approximating an elliptic sector. | ![]() SELECT MakeEllipticSector(0, 0, 100, 50, 330, 30, -1, 1); |
![]() SELECT MakeEllipticSector(0, 0, 100, 50, 30, 330, -1, 1); |
MakeCircularStripe ( cx, cy, radius_1, radius_2, start, stop ) MakeCircularStripe ( cx, cy, radius_1, radius_2, start, stop, srid ) MakeCircularStripe ( cx, cy, radius_1, radius_2, start, stop, srid, step ) Will return a Polygon delimited by two circular arcs sharing the same centre but having different radii. | ![]() SELECT MakeCircularStripe(0, 0, 100, 90, 45, 315, -1, 1); |
![]() SELECT MakeCircularStripe(0, 0, 50, 150, 315, 45, -1, 1); |
Any function supporting circles and ellipses could obviously be nested with any other Spatial SQL function so to get more elaborate results. e.g. RotateCoords() and ShiftCoords() could be invoked in order to apply an arbitrary roto-translation. | ![]() SELECT RotateCoords( MakeEllipse(0, 0, 100, 20, -1, 1), 45); |
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