线段:line 函数
CV_EXPORTS_W void line(CV_IN_OUT Mat& img, Point pt1, Point pt2, const Scalar& color, int thickness=1, int lineT ype=8, int shift=0);
- img: 要绘制线段的图像。
- pt1: 线段的起点。
- pt2: 线段的终点。
- color: 线段的颜色,通过一个Scalar对象定义。
- thickness: 线条的宽度。
- lineType: 线段的类型。可以取值8, 4, 和CV_AA, 分别代表8邻接连接线,4邻接连接线和反锯齿连接线。默认值为8邻接。为了获得更好地效果可以选用CV_AA(采用了高斯滤波)。
- shift: 坐标点小数点位数。
椭圆:ellipse 函数
CV_EXPORTS_W void ellipse(CV_IN_OUT Mat& img, Point center, Size axes,double angle, double startAngle, double endAngle, const Scalar& color, int thickness=1,int lineType=8, int shift=0);
- img: 要绘制椭圆的图像。
- center: 椭圆中心点坐标。
- axes: 椭圆位于该Size决定的矩形内。(即定义长轴和短轴)。
- angle: 椭圆旋转角度。
- startAngle: 椭圆开始绘制时角度。
- endAngle: 椭圆绘制结束时角度。(若绘制一个完整的椭圆,则startAngle=0, endAngle = 360)。
- color: 椭圆的颜色。
- thickness: 绘制椭圆线粗。负数表示全部填充。
- lineType、shift:同上。
矩形:rectangle 函数
CV_EXPORTS_W void rectangle(CV_IN_OUT Mat& img, Point pt1, Point pt2, const Scalar& color, int thickness=1, int lineType=8, int shift=0);
- pt1: 矩形的左上角坐标。
- pt2: 矩阵的右下角坐标。
- 其余同上。
圆:circle 函数
CV_EXPORTS_W void circle(CV_IN_OUT Mat& img, Point center, int radius, const Scalar& color, int thickness=1, int lineType=8, int shift=0);
- center: 圆心坐标。
- radius: 半径。
- 其余同上。
填充多边形:fillPoly 函数
CV_EXPORTS void fillPoly(Mat& img, const Point** pts,const int* npts, int ncontours, const Scalar& color, int lineType=8, int shift=0, Point offset=Point() );
- pts: 多边形定点集。
- npts: 多边形的顶点数目。
- ncontours: 要绘制多边形的数量。
- offset: 所有点轮廓的可选偏移。
- 其余同上。
显示文字:PutText 函数
void putText(Mat& img, const string& text, Point org, int fontFace, double fontScale, Scalar color, int thickness=1, int lineType=8, bool bottomLeftOrigin=false )
- img – 显示文字所在图像.
- text – 待显示的文字.
- org – 文字在图像中的左下角 坐标.
- font – 字体结构体.
- fontFace – 字体类型, 可选择字体:
FONT_HERSHEY_SIMPLEX, FONT_HERSHEY_PLAIN,
FONT_HERSHEY_DUPLEX, FONT_HERSHEY_COMPLEX,
FONT_HERSHEY_TRIPLEX, FONT_HERSHEY_COMPLEX_SMALL,
FONT_HERSHEY_SCRIPT_SIMPLEX, or FONT_HERSHEY_SCRIPT_COMPLEX,
以上所有类型都可以配合FONT_HERSHEY_ITALIC使用,产生斜体效果。
- fontScale – 字体大小,该值和字体内置大小相乘得到字体大小
- color – 文本颜色
- thickness – 写字的线的粗细
- lineType – 线型.
- bottomLeftOrigin – true, 图像数据原点在左下角。否则, 图像数据原点在左上角.
示例
#include
#include
#include
using namespace cv;
#define WINDOW_NAME1 "[绘制图1]" //为窗口标题定义的宏
#define WINDOW_NAME2 "[绘制图2]" //为窗口标题定义的宏
#define WINDOW_WIDTH 600 //定义窗口大小的宏
//绘制不同角度。相同尺寸的椭圆
void DrawEllipse(Mat img, double angle)
{
int thickness = 2;
int lineType = 8;
ellipse(img, Point(WINDOW_WIDTH / 2, WINDOW_WIDTH / 2),
Size(WINDOW_WIDTH / 4, WINDOW_WIDTH / 16), angle,
0, 360, Scalar(255, 129, 0), thickness, lineType);
}
//绘制实心圆
void DrawFilledCircle(Mat img, Point center)
{
int thickness = -1; //线粗
int lineType = 8;
circle(img, center, WINDOW_WIDTH / 32, Scalar(0, 0, 255),
thickness, lineType);
}
//实现凹多边形绘制
void DrawPolygon(Mat img)
{
int lineType = 8;
//创建一些点
Point rootPoints[1][20];
rootPoints[0][0] = Point(WINDOW_WIDTH / 4, 7 * WINDOW_WIDTH / 8);
rootPoints[0][1] = Point(3 * WINDOW_WIDTH / 4, 7 * WINDOW_WIDTH / 8);
rootPoints[0][2] = Point(3 * WINDOW_WIDTH / 4, 13 * WINDOW_WIDTH / 16);
rootPoints[0][3] = Point(11 * WINDOW_WIDTH / 16, 13 * WINDOW_WIDTH / 16);
rootPoints[0][4] = Point(19 * WINDOW_WIDTH / 32, 3 * WINDOW_WIDTH / 8);
rootPoints[0][5] = Point(3 * WINDOW_WIDTH / 4, 3 * WINDOW_WIDTH / 8);
rootPoints[0][6] = Point(3 * WINDOW_WIDTH / 4, WINDOW_WIDTH / 8);
rootPoints[0][7] = Point(26 * WINDOW_WIDTH / 40, WINDOW_WIDTH / 8);
rootPoints[0][8] = Point(26 * WINDOW_WIDTH / 40, WINDOW_WIDTH / 4);
rootPoints[0][9] = Point(22 * WINDOW_WIDTH / 40, WINDOW_WIDTH / 4);
rootPoints[0][10] = Point(22 * WINDOW_WIDTH / 40, WINDOW_WIDTH / 8);
rootPoints[0][11] = Point(18 * WINDOW_WIDTH / 40, WINDOW_WIDTH / 8);
rootPoints[0][12] = Point(18 * WINDOW_WIDTH / 40, WINDOW_WIDTH / 4);
rootPoints[0][13] = Point(14 * WINDOW_WIDTH / 40, WINDOW_WIDTH / 4);
rootPoints[0][14] = Point(14 * WINDOW_WIDTH / 40, WINDOW_WIDTH / 8);
rootPoints[0][15] = Point(WINDOW_WIDTH / 4, WINDOW_WIDTH / 8);
rootPoints[0][16] = Point(WINDOW_WIDTH / 4, 3 * WINDOW_WIDTH / 8);
rootPoints[0][17] = Point(13 * WINDOW_WIDTH / 32, 3 * WINDOW_WIDTH / 8);
rootPoints[0][18] = Point(5 * WINDOW_WIDTH / 16, 13 * WINDOW_WIDTH / 16);
rootPoints[0][19] = Point(WINDOW_WIDTH / 4, 13 * WINDOW_WIDTH / 16);
const Point* ppt[1] = { rootPoints[0] };
int npt[] = { 20 };
fillPoly(img, ppt, npt, 1, Scalar(255, 255, 255), lineType);
}
// 绘制线
void DrawLine(Mat img, Point start, Point end)
{
int thickness = 2;
int lineType = 8;
line(img, start, end, Scalar(0, 0, 0), thickness, lineType);
}
int main()
{
//创建空白的Mat图像
Mat atomImage = Mat::zeros(WINDOW_WIDTH, WINDOW_WIDTH, CV_8UC3);
Mat rookImage = Mat::zeros(WINDOW_WIDTH, WINDOW_WIDTH, CV_8UC3);
//----------- 绘制化学中原子的示例图-----------
//1.先绘制出椭圆
DrawEllipse(atomImage, 90);
DrawEllipse(atomImage, 0);
DrawEllipse(atomImage, 45);
DrawEllipse(atomImage, -45);
//2.再绘制出圆心
DrawFilledCircle(atomImage, Point(WINDOW_WIDTH / 2, WINDOW_WIDTH / 2));
//----------- 绘制组合图形----------------
//1.线绘制出多边形
DrawPolygon(rookImage);
//2.绘制矩形
rectangle(rookImage, Point(0, 7 * WINDOW_WIDTH),
Point(WINDOW_WIDTH, WINDOW_WIDTH), Scalar(0, 255, 255), -1, 8);
//2.绘制一些线段
DrawLine(rookImage, Point(0, 15 * WINDOW_WIDTH / 16),
Point(WINDOW_WIDTH, 15 * WINDOW_WIDTH / 16));
DrawLine(rookImage, Point(WINDOW_WIDTH / 4, 7 * WINDOW_WIDTH / 8),
Point(WINDOW_WIDTH / 4, WINDOW_WIDTH));
DrawLine(rookImage, Point(WINDOW_WIDTH / 2, 7 * WINDOW_WIDTH / 8),
Point(WINDOW_WIDTH / 2, WINDOW_WIDTH));
DrawLine(rookImage, Point(3 * WINDOW_WIDTH / 4, 7 * WINDOW_WIDTH / 8),
Point(3 * WINDOW_WIDTH / 4, WINDOW_WIDTH));
//3.显示绘制出的图像
imshow(WINDOW_NAME1, atomImage);
moveWindow(WINDOW_NAME1, 0, 200);
imshow(WINDOW_NAME2, rookImage);
moveWindow(WINDOW_NAME2, WINDOW_WIDTH, 200);
waitKey(0);
return 0;
}