doc/tutorials/viz/widget_pose/widget_pose.markdown

   1 Pose of a widget {#tutorial_widget_pose}
   2 ================
   3
   4 Goal
   5 ----
   6
   7 In this tutorial you will learn how to
   8
   9 -   Add widgets to the visualization window
  10 -   Use Affine3 to set pose of a widget
  11 -   Rotating and translating a widget along an axis
  12
  13 Code
  14 ----
  15
  16 You can download the code from [here ](https://github.com/opencv/opencv/tree/3.4/samples/cpp/tutorial_code/viz/widget_pose.cpp).
  17 @include samples/cpp/tutorial_code/viz/widget_pose.cpp
  18
  19 Explanation
  20 -----------
  21
  22 Here is the general structure of the program:
  23
  24 -   Create a visualization window.
  25     @code{.cpp}
  26     /// Create a window
  27     viz::Viz3d myWindow("Coordinate Frame");
  28     @endcode
  29 -   Show coordinate axes in the window using CoordinateSystemWidget.
  30     @code{.cpp}
  31     /// Add coordinate axes
  32     myWindow.showWidget("Coordinate Widget", viz::WCoordinateSystem());
  33     @endcode
  34 -   Display a line representing the axis (1,1,1).
  35     @code{.cpp}
  36     /// Add line to represent (1,1,1) axis
  37     viz::WLine axis(Point3f(-1.0f,-1.0f,-1.0f), Point3f(1.0f,1.0f,1.0f));
  38     axis.setRenderingProperty(viz::LINE_WIDTH, 4.0);
  39     myWindow.showWidget("Line Widget", axis);
  40     @endcode
  41 -   Construct a cube.
  42     @code{.cpp}
  43     /// Construct a cube widget
  44     viz::WCube cube_widget(Point3f(0.5,0.5,0.0), Point3f(0.0,0.0,-0.5), true, viz::Color::blue());
  45     cube_widget.setRenderingProperty(viz::LINE_WIDTH, 4.0);
  46     myWindow.showWidget("Cube Widget", cube_widget);
  47     @endcode
  48 -   Create rotation matrix from rodrigues vector
  49     @code{.cpp}
  50     /// Rotate around (1,1,1)
  51     rot_vec.at<float>(0,0) += CV_PI * 0.01f;
  52     rot_vec.at<float>(0,1) += CV_PI * 0.01f;
  53     rot_vec.at<float>(0,2) += CV_PI * 0.01f;
  54
  55     ...
  56
  57     Mat rot_mat;
  58     Rodrigues(rot_vec, rot_mat);
  59     @endcode
  60 -   Use Affine3f to set pose of the cube.
  61     @code{.cpp}
  62     /// Construct pose
  63     Affine3f pose(rot_mat, Vec3f(translation, translation, translation));
  64     myWindow.setWidgetPose("Cube Widget", pose);
  65     @endcode
  66 -   Animate the rotation using wasStopped and spinOnce
  67     @code{.cpp}
  68     while(!myWindow.wasStopped())
  69     {
  70         ...
  71
  72         myWindow.spinOnce(1, true);
  73     }
  74     @endcode
  75
  76 Results
  77 -------
  78
  79 Here is the result of the program.
  80
  81 \htmlonly
  82 <div align="center">
  83 <iframe width="420" height="315" src="https://www.youtube.com/embed/22HKMN657U0" frameborder="0" allowfullscreen></iframe>
  84 </div>
  85 \endhtmlonly