contains method
- Offset point
Whether the point specified by the given offset (which is assumed to be relative to the origin) lies inside the rounded rectangle.
This method may allocate (and cache) a copy of the object with normalized radii the first time it is called on a particular RRect instance. When using this method, prefer to reuse existing RRects rather than recreating the object each time.
Implementation
bool contains(Offset point) {
if (point.dx < left || point.dx >= right || point.dy < top || point.dy >= bottom) {
return false;
} // outside bounding box
final RRect scaled = scaleRadii();
double x;
double y;
double radiusX;
double radiusY;
// check whether point is in one of the rounded corner areas
// x, y -> translate to ellipse center
if (point.dx < left + scaled.tlRadiusX &&
point.dy < top + scaled.tlRadiusY) {
x = point.dx - left - scaled.tlRadiusX;
y = point.dy - top - scaled.tlRadiusY;
radiusX = scaled.tlRadiusX;
radiusY = scaled.tlRadiusY;
} else if (point.dx > right - scaled.trRadiusX &&
point.dy < top + scaled.trRadiusY) {
x = point.dx - right + scaled.trRadiusX;
y = point.dy - top - scaled.trRadiusY;
radiusX = scaled.trRadiusX;
radiusY = scaled.trRadiusY;
} else if (point.dx > right - scaled.brRadiusX &&
point.dy > bottom - scaled.brRadiusY) {
x = point.dx - right + scaled.brRadiusX;
y = point.dy - bottom + scaled.brRadiusY;
radiusX = scaled.brRadiusX;
radiusY = scaled.brRadiusY;
} else if (point.dx < left + scaled.blRadiusX &&
point.dy > bottom - scaled.blRadiusY) {
x = point.dx - left - scaled.blRadiusX;
y = point.dy - bottom + scaled.blRadiusY;
radiusX = scaled.blRadiusX;
radiusY = scaled.blRadiusY;
} else {
return true; // inside and not within the rounded corner area
}
x = x / radiusX;
y = y / radiusY;
// check if the point is outside the unit circle
if (x * x + y * y > 1.0) {
return false;
}
return true;
}