draw_circleT_draw_circleDrawCircleDrawCircle (Operator)
Name
draw_circleT_draw_circleDrawCircleDrawCircle — Interactive drawing of a circle.
Signature
Description
draw_circledraw_circleDrawCircleDrawCircleDrawCircle produces the parameter for a circle created interactive by
the user in the window.
To create a circle you have to press the mouse button at the location which is used
as the center of that circle. While keeping the mouse button pressed, the
RadiusRadiusRadiusRadiusradius's length can be modified through moving the mouse.
After another mouse click in the created circle center you can move it.
A clicking close to the circular arc you can modify the RadiusRadiusRadiusRadiusradius of
the circle.
Pressing the right mouse button terminates the procedure. On macOS
draw_circledraw_circleDrawCircleDrawCircleDrawCircle can also be terminated by pressing the escape key.
After terminating the procedure the circle is not visible in the window any longer.
Attention
If used in a buffer window, mouse events have to be supplied by the
application, while the draw operator must be run in another thread.
Execution Information
- Multithreading type: reentrant (runs in parallel with non-exclusive operators).
- Multithreading scope: global (may be called from any thread).
- Processed without parallelization.
Parameters
WindowHandleWindowHandleWindowHandleWindowHandlewindowHandle (input_control) window → HWindow, HTupleHTupleHtuple (handle) (IntPtr) (HHandle) (handle)
Window handle.
RowRowRowRowrow (output_control) circle.center.y → HTupleHTupleHtuple (real) (double) (double) (double)
Barycenter's row index.
ColumnColumnColumnColumncolumn (output_control) circle.center.x → HTupleHTupleHtuple (real) (double) (double) (double)
Barycenter's column index.
RadiusRadiusRadiusRadiusradius (output_control) circle.radius → HTupleHTupleHtuple (real) (double) (double) (double)
Circle's radius.
Example (HDevelop)
read_image(Image,'monkey')
draw_circle(WindowHandle,Row,Column,Radius)
gen_circle(Circle,Row,Column,Radius)
reduce_domain(Image,Circle,ImageReduced)
invert_image (ImageReduced, ImageInvert)
dev_display (ImageInvert)
Example (C)
read_image(&Image,"monkey");
draw_circle(WindowHandle,&Row,&Column,&Radius);
gen_circle(&Circle,Row,Column,Radius);
reduce_domain(Image,Circle,&GrayCircle);
disp_image(GrayCircle,WindowHandle);
Example (HDevelop)
read_image(Image,'monkey')
draw_circle(WindowHandle,Row,Column,Radius)
gen_circle(Circle,Row,Column,Radius)
reduce_domain(Image,Circle,ImageReduced)
invert_image (ImageReduced, ImageInvert)
dev_display (ImageInvert)
Example (HDevelop)
read_image(Image,'monkey')
draw_circle(WindowHandle,Row,Column,Radius)
gen_circle(Circle,Row,Column,Radius)
reduce_domain(Image,Circle,ImageReduced)
invert_image (ImageReduced, ImageInvert)
dev_display (ImageInvert)
Example (HDevelop)
read_image(Image,'monkey')
draw_circle(WindowHandle,Row,Column,Radius)
gen_circle(Circle,Row,Column,Radius)
reduce_domain(Image,Circle,ImageReduced)
invert_image (ImageReduced, ImageInvert)
dev_display (ImageInvert)
Result
draw_circledraw_circleDrawCircleDrawCircleDrawCircle returns 2 (H_MSG_TRUE) if the window is valid and the
needed drawing mode (see set_insertset_insertSetInsertSetInsertSetInsert) is available.
If necessary, an exception is raised.
Possible Predecessors
open_windowopen_windowOpenWindowOpenWindowOpenWindow
Possible Successors
reduce_domainreduce_domainReduceDomainReduceDomainReduceDomain,
disp_regiondisp_regionDispRegionDispRegionDispRegion,
set_coloredset_coloredSetColoredSetColoredSetColored,
set_line_widthset_line_widthSetLineWidthSetLineWidthSetLineWidth,
set_drawset_drawSetDrawSetDrawSetDraw,
set_insertset_insertSetInsertSetInsertSetInsert
Alternatives
draw_circle_moddraw_circle_modDrawCircleModDrawCircleModDrawCircleMod,
draw_ellipsedraw_ellipseDrawEllipseDrawEllipseDrawEllipse,
draw_regiondraw_regionDrawRegionDrawRegionDrawRegion
See also
gen_circlegen_circleGenCircleGenCircleGenCircle,
draw_rectangle1draw_rectangle1DrawRectangle1DrawRectangle1DrawRectangle1,
draw_rectangle2draw_rectangle2DrawRectangle2DrawRectangle2DrawRectangle2,
draw_polygondraw_polygonDrawPolygonDrawPolygonDrawPolygon,
set_insertset_insertSetInsertSetInsertSetInsert
Module
Foundation