void MgArc::_update()
{
Point2d points[16];
int n = mgAngleArcToBezier(points, getCenter(), getRadius(), 0, getStartAngle(), getSweepAngle());
mgBeziersBox(_extent, n, points);
}
bool MgArc::_hitTestBox(const Box2d& rect) const
{
if (!getExtent().isIntersect(rect))
return false;
Point2d points[16];
int n = mgAngleArcToBezier(points, getCenter(), getRadius(), 0, getStartAngle(), getSweepAngle());
return mgBeziersIntersectBox(rect, n, points);
}
float MgArc::_hitTest(const Point2d& pt, float tol,
Point2d& nearpt, int&) const
{
Point2d points[16];
int n = mgAngleArcToBezier(points, getCenter(), getRadius(), 0, getStartAngle(), getSweepAngle());
float distMin = _FLT_MAX;
Point2d ptTemp;
for (int i = 0; i + 3 < n; i += 3) {
mgNearestOnBezier(pt, points + i, ptTemp);
float dist = pt.distanceTo(ptTemp);
if (dist <= tol && dist < distMin) {
distMin = dist;
nearpt = ptTemp;
}
}
return distMin;
}
bool GiGraphics::drawArc(const GiContext* ctx,
const Point2d& center, float rx, float ry,
float startAngle, float sweepAngle,
bool modelUnit)
{
if (m_impl->drawRefcnt == 0 || rx < _MGZERO || fabs(sweepAngle) < 1e-5f)
return false;
GiLock lock (&m_impl->drawRefcnt);
if (ry < _MGZERO)
ry = rx;
if (!DRAW_RECT(m_impl, modelUnit).isIntersect(Box2d(center, 2 * rx, 2 * ry)))
return false;
Point2d points[16];
int count = mgAngleArcToBezier(points, center,
rx, ry, startAngle, sweepAngle);
S2D(xf(), modelUnit).TransformPoints(count, points);
return count > 3 && rawBeziers(ctx, points, count);
}
bool GiGraphics::drawPie(const GiContext* ctx,
const Point2d& center, float rx, float ry,
float startAngle, float sweepAngle,
bool modelUnit)
{
if (m_impl->drawRefcnt == 0 || rx < _MGZERO || fabs(sweepAngle) < 1e-5f)
return false;
GiLock lock (&m_impl->drawRefcnt);
if (ry < _MGZERO)
ry = rx;
const Box2d extent (center, rx*2.f, ry*2.f); // 模型坐标范围
if (!DRAW_RECT(m_impl, modelUnit).isIntersect(extent)) // 全部在显示区域外
return false;
Point2d points[16];
int count = mgAngleArcToBezier(points, center,
rx, ry, startAngle, sweepAngle);
if (count < 4)
return false;
S2D(xf(), modelUnit).TransformPoints(count, points);
Point2d cen(center * S2D(xf(), modelUnit));
bool ret = rawBeginPath();
if (ret)
{
ret = rawMoveTo(cen.x, cen.y);
ret = rawLineTo(points[0].x, points[0].y);
ret = rawBezierTo(points + 1, count - 1);
ret = rawClosePath();
ret = rawEndPath(ctx, true);
}
return ret;
}
