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改进平滑曲线

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This commit is contained in:
feiyangqingyun
2021-03-09 09:56:59 +08:00
parent cd0029a6de
commit 3a4b44cd58
9 changed files with 91 additions and 31 deletions
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28
smoothcurve/smoothcurve.cpp
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@@ -1,4 +1,5 @@
#include "smoothcurve.h"
#include "qdebug.h"
QPainterPath SmoothCurve::createSmoothCurve(const QVector<QPointF> &points)
{
@@ -20,6 +21,29 @@ QPainterPath SmoothCurve::createSmoothCurve(const QVector<QPointF> &points)
return path;
}
QPainterPath SmoothCurve::createSmoothCurve2(const QVector<QPointF> &points)
{
//采用Qt原生方法不做任何处理
int count = points.count();
if (count == 0) {
return QPainterPath();
}
QPainterPath path(points.at(0));
for (int i = 0; i < count - 1; ++i) {
//控制点的 x 坐标为 sp 与 ep 的 x 坐标和的一半
//第一个控制点 c1 的 y 坐标为起始点 sp 的 y 坐标
//第二个控制点 c2 的 y 坐标为结束点 ep 的 y 坐标
QPointF sp = points.at(i);
QPointF ep = points.at(i + 1);
QPointF c1 = QPointF((sp.x() + ep.x()) / 2, sp.y());
QPointF c2 = QPointF((sp.x() + ep.x()) / 2, ep.y());
path.cubicTo(c1, c2, ep);
}
return path;
}
void SmoothCurve::calculateFirstControlPoints(double *&result, const double *rhs, int n)
{
result = new double[n];
@@ -41,8 +65,8 @@ void SmoothCurve::calculateFirstControlPoints(double *&result, const double *rhs
}
void SmoothCurve::calculateControlPoints(const QVector<QPointF> &datas,
QVector<QPointF> *firstControlPoints,
QVector<QPointF> *secondControlPoints)
QVector<QPointF> *firstControlPoints,
QVector<QPointF> *secondControlPoints)
{
int n = datas.size() - 1;
for (int i = 0; i < n; ++i) {