Added sample code for tutorial - cpp

samples/cpp/tutorial_code/Basic/Drawing_1.cpp

@@ -0,0 +1,172 @@
+/**
+ * @file Drawing_1.cpp
+ * @brief Simple sample code
+ */
+
+#include <opencv2/core/core.hpp>
+#include <opencv2/highgui/highgui.hpp>
+
+#define w 400
+
+using namespace cv;
+
+/// Function headers
+void MyEllipse( Mat img, double angle );
+void MyFilledCircle( Mat img, Point center );
+void MyPolygon( Mat img );
+void MyLine( Mat img, Point start, Point end );
+
+/**
+ * @function main
+ * @brief Main function
+ */
+int main( int argc, char **argv ){
+
+  /// Windows names
+  char atom_window[] = "Drawing 1: Atom";
+  char rook_window[] = "Drawing 2: Rook";
+
+  /// Create black empty images 
+  Mat atom_image = Mat::zeros( w, w, CV_8UC3 );
+  Mat rook_image = Mat::zeros( w, w, CV_8UC3 );
+
+  /// 1. Draw a simple atom:
+  /// -----------------------
+
+  /// 1.a. Creating ellipses 
+  MyEllipse( atom_image, 90 );
+  MyEllipse( atom_image, 0 );
+  MyEllipse( atom_image, 45 );
+  MyEllipse( atom_image, -45 );
+
+  /// 1.b. Creating circles
+  MyFilledCircle( atom_image, Point( w/2.0, w/2.0) );
+
+  /// 2. Draw a rook
+  /// ------------------
+
+  /// 2.a. Create a convex polygon
+  MyPolygon( rook_image );
+
+  /// 2.b. Creating rectangles
+  rectangle( rook_image,
+	     Point( 0, 7*w/8.0 ),
+	     Point( w, w),
+	     Scalar( 0, 255, 255 ),
+	     -1,
+	     8 );
+
+  /// 2.c. Create a few lines 
+  MyLine( rook_image, Point( 0, 15*w/16 ), Point( w, 15*w/16 ) );
+  MyLine( rook_image, Point( w/4, 7*w/8 ), Point( w/4, w ) );
+  MyLine( rook_image, Point( w/2, 7*w/8 ), Point( w/2, w ) );
+  MyLine( rook_image, Point( 3*w/4, 7*w/8 ), Point( 3*w/4, w ) );
+
+  /// 3. Display your stuff!
+  imshow( atom_window, atom_image );
+  cvMoveWindow( atom_window, 0, 200 );
+  imshow( rook_window, rook_image );
+  cvMoveWindow( rook_window, w, 200 );
+
+  waitKey( 0 );
+  return(0);
+}
+
+/// Function Declaration
+
+/**
+ * @function MyEllipse
+ * @brief Draw a fixed-size ellipse with different angles
+ */
+void MyEllipse( Mat img, double angle )
+{
+  int thickness = 2;
+  int lineType = 8;
+
+  ellipse( img,
+	   Point( w/2.0, w/2.0 ),
+	   Size( w/4.0, w/16.0 ),
+	   angle,
+	   0, 
+	   360,
+	   Scalar( 255, 0, 0 ),
+	   thickness,
+	   lineType );  
+}
+
+/**
+ * @function MyFilledCircle
+ * @brief Draw a fixed-size filled circle
+ */
+void MyFilledCircle( Mat img, Point center )
+{
+  int thickness = -1;
+  int lineType = 8;
+
+  circle( img, 
+	  center,
+	  w/32.0,
+	  Scalar( 0, 0, 255 ),
+	  thickness, 
+	  lineType );
+}
+
+/**
+ * @function MyPolygon
+ * @function Draw a simple concave polygon (rook)
+ */
+void MyPolygon( Mat img )
+{
+  int lineType = 8;
+
+  /** Create some points */
+  Point rook_points[1][20];
+  rook_points[0][0] = Point( w/4.0, 7*w/8.0 );
+  rook_points[0][1] = Point( 3*w/4.0, 7*w/8.0 );
+  rook_points[0][2] = Point( 3*w/4.0, 13*w/16.0 );
+  rook_points[0][3] = Point( 11*w/16.0, 13*w/16.0 );
+  rook_points[0][4] = Point( 19*w/32.0, 3*w/8.0 );
+  rook_points[0][5] = Point( 3*w/4.0, 3*w/8.0 );
+  rook_points[0][6] = Point( 3*w/4.0, w/8.0 );
+  rook_points[0][7] = Point( 26*w/40.0, w/8.0 );
+  rook_points[0][8] = Point( 26*w/40.0, w/4.0 );
+  rook_points[0][9] = Point( 22*w/40.0, w/4.0 );
+  rook_points[0][10] = Point( 22*w/40.0, w/8.0 );
+  rook_points[0][11] = Point( 18*w/40.0, w/8.0 );
+  rook_points[0][12] = Point( 18*w/40.0, w/4.0 );
+  rook_points[0][13] = Point( 14*w/40.0, w/4.0 );
+  rook_points[0][14] = Point( 14*w/40.0, w/8.0 );
+  rook_points[0][15] = Point( w/4.0, w/8.0 );
+  rook_points[0][16] = Point( w/4.0, 3*w/8.0 );
+  rook_points[0][17] = Point( 13*w/32.0, 3*w/8.0 );
+  rook_points[0][18] = Point( 5*w/16.0, 13*w/16.0 );
+  rook_points[0][19] = Point( w/4.0, 13*w/16.0) ;
+
+  const Point* ppt[1] = { rook_points[0] };
+  int npt[] = { 20 };
+
+  fillPoly( img,
+	    ppt,
+	    npt,
+            1,
+	    Scalar( 255, 255, 255 ),
+	    lineType );			
+}
+
+/**
+ * @function MyLine
+ * @brief Draw a simple line
+ */
+void MyLine( Mat img, Point start, Point end )
+{
+  int thickness = 2;
+  int lineType = 8;
+  line( img, 
+	start,
+	end,
+	Scalar( 0, 0, 0 ),
+	thickness,
+	lineType );
+}
+
+