Drawing

List of Operators ↓

This chapter describes operators that allow the user to manually draw geometric shapes. They require mouse interaction and in general block the application until the mouse interaction is finished. For non-blocking interactive creation of geometric shapes, HALCON also provides drawing objects with the operators listed in Graphics / Object.

General Objectives

The draw operators draw_regiondraw_regionDrawRegionDrawRegionDrawRegion, draw_xlddraw_xldDrawXldDrawXldDrawXld, draw_xld_moddraw_xld_modDrawXldModDrawXldModDrawXldMod, draw_nurbsdraw_nurbsDrawNurbsDrawNurbsDrawNurbs, draw_nurbs_moddraw_nurbs_modDrawNurbsModDrawNurbsModDrawNurbsMod, draw_nurbs_interpdraw_nurbs_interpDrawNurbsInterpDrawNurbsInterpDrawNurbsInterp, draw_nurbs_interp_moddraw_nurbs_interp_modDrawNurbsInterpModDrawNurbsInterpModDrawNurbsInterpMod, as well as drag_region1drag_region1DragRegion1DragRegion1DragRegion1, drag_region2drag_region2DragRegion2DragRegion2DragRegion2 and drag_region3drag_region3DragRegion3DragRegion3DragRegion3 return iconic objects. All other draw operators return the geometric parameters that are needed to create regions or contours in the respective shape (see table). Most draw operators have a modifying variant that allows the user to specify the initial parameters of the shown shape.

Drawing in Buffer Windows

Because the draw operators rely on mouse interaction, they generally do not work when used with buffer windows (see open_windowopen_windowOpenWindowOpenWindowOpenWindow), so you should use drawing objects instead. Nevertheless some operators (see table) can be used in buffer windows. These operators are controlled through a mouse state. In order to use these operators (and to not cause a deadlock) the application has to provide the mouse state with the operators send_mouse_double_click_eventsend_mouse_double_click_eventSendMouseDoubleClickEventSendMouseDoubleClickEventSendMouseDoubleClickEvent, send_mouse_down_eventsend_mouse_down_eventSendMouseDownEventSendMouseDownEventSendMouseDownEvent, send_mouse_drag_eventsend_mouse_drag_eventSendMouseDragEventSendMouseDragEventSendMouseDragEvent and send_mouse_up_eventsend_mouse_up_eventSendMouseUpEventSendMouseUpEventSendMouseUpEvent as well as the state of the modifier keys (also by using send_mouse_drag_eventsend_mouse_drag_eventSendMouseDragEventSendMouseDragEventSendMouseDragEvent), whereas the draw operators themselves must be run in another thread. While using the draw operator, the image section must not be changed.

List of Operators

drag_region1DragRegion1DragRegion1drag_region1

Interactive moving of a region.

drag_region2DragRegion2DragRegion2drag_region2

Interactive movement of a region with fixpoint specification.

drag_region3DragRegion3DragRegion3drag_region3

Interactive movement of a region with restriction of positions.

draw_circleDrawCircleDrawCircledraw_circle

Interactive drawing of a circle.

draw_circle_modDrawCircleModDrawCircleModdraw_circle_mod

Interactive drawing of a circle.

draw_ellipseDrawEllipseDrawEllipsedraw_ellipse

Interactive drawing of an ellipse.

draw_ellipse_modDrawEllipseModDrawEllipseModdraw_ellipse_mod

Interactive drawing of an ellipse.

draw_lineDrawLineDrawLinedraw_line

Draw a line.

draw_line_modDrawLineModDrawLineModdraw_line_mod

Draw a line.

draw_nurbsDrawNurbsDrawNurbsdraw_nurbs

Interactive drawing of a NURBS curve.

draw_nurbs_interpDrawNurbsInterpDrawNurbsInterpdraw_nurbs_interp

Interactive drawing of a NURBS curve using interpolation.

draw_nurbs_interp_modDrawNurbsInterpModDrawNurbsInterpModdraw_nurbs_interp_mod

Interactive modification of a NURBS curve using interpolation.

draw_nurbs_modDrawNurbsModDrawNurbsModdraw_nurbs_mod

Interactive modification of a NURBS curve.

draw_pointDrawPointDrawPointdraw_point

Draw a point.

draw_point_modDrawPointModDrawPointModdraw_point_mod

Draw a point.

draw_polygonDrawPolygonDrawPolygondraw_polygon

Interactive drawing of a polygon row.

draw_rectangle1DrawRectangle1DrawRectangle1draw_rectangle1

Draw a rectangle parallel to the coordinate axis.

draw_rectangle1_modDrawRectangle1ModDrawRectangle1Moddraw_rectangle1_mod

Draw a rectangle parallel to the coordinate axis.

draw_rectangle2DrawRectangle2DrawRectangle2draw_rectangle2

Interactive drawing of any orientated rectangle.

draw_rectangle2_modDrawRectangle2ModDrawRectangle2Moddraw_rectangle2_mod

Interactive drawing of any orientated rectangle.

draw_regionDrawRegionDrawRegiondraw_region

Interactive drawing of a closed region.

draw_xldDrawXldDrawXlddraw_xld

Interactive drawing of a contour.

draw_xld_modDrawXldModDrawXldModdraw_xld_mod

Interactive modification of a contour.