VPClip using C#
I assume you want to write code to do the same thing as AutoCAD built-in command "VPCLIP", using .NET API (C# or VB.NET does not matter here), right?
It is rather simple, if you loot at the Viewport class in .NET API document/VisualStudio's Object Browser:
Viewport class has a couple of read/write properties: "NonRectClipEntityId" (ObjectId of a Polyline) and "NonRectClipOn" (boolean).
So, here are what you do:
1. Find the target Viewport's Id (you can ask user to pick, loop through entities in paperspace, ...)
2. Find an existing polyline (closed, of course) in the same space as the viewport. You can ask user to pick. Or you have a set of points that can be turned into a polyline.
3. Once you have both target viewport ID and an existing polyline Id (or a set of point that you can create a polyline by code), you start a transaction, open the viewport object, set its "NonRectClipEntityId" to the polyline's Id, and then set "NonrectClicpOn" to true. Commit the transaction. You are done.
As I said in previous reply, it is quite simple to clip a viewport with an polyline: simply assign the polyline's Id to the viewport.
I suppose you rushed you code so that there are quite a few lines that do not make sense (thus not worked as you expected): although the code asked user to pick a viewport and a polyline, your code somehow created 2 new Viewport objects and only one is added to the database. However, the viewport is added into wrong space - ModelSpace, and then the code is apply the clipping polyline to the not-see-able viewport.
So, the problem with your code is not how to clip a viewport, rather, it is getting a target viewport and clipping polyline PROPERLY/AS EXPECTED.
Anyway, here is some simple code to clip a viewport:
using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.DatabaseServices;
using Autodesk.AutoCAD.EditorInput;
using Autodesk.AutoCAD.Runtime;
using System;
using CadApp = Autodesk.AutoCAD.ApplicationServices.Application;
[assembly: CommandClass(typeof(SetNoRectViewport.MyCommands))]
namespace SetNoRectViewport
{
public class MyCommands
{
[CommandMethod("ClipVp", CommandFlags.NoTileMode)]
public static void RunDocCommand()
{
var dwg = CadApp.DocumentManager.MdiActiveDocument;
var ed = dwg.Editor;
try
{
ClipViewport(dwg);
}
catch(System.Exception ex)
{
ed.WriteMessage("\nError: {0}", ex.Message);
ed.WriteMessage("\n*Cancel*");
}
finally
{
Autodesk.AutoCAD.Internal.Utils.PostCommandPrompt();
}
}
private static void ClipViewport(Document dwg)
{
Editor ed = dwg.Editor;
ed.SwitchToPaperSpace();
//Select a Viewport
var vpId = SelectEntity(
ed,
typeof(Viewport),
"\nSelect a viewport:");
if (vpId.IsNull)
{
ed.WriteMessage("\n*Cancel*");
return;
}
HighlightEntity(vpId, true);
//Select a polyline in the same layout
var polyId = SelectEntity(
ed,
typeof(Polyline),
"\nSelect a polyline in the same layout as the selected viewport:");
if (polyId.IsNull)
{
HighlightEntity(vpId, false);
ed.WriteMessage("\n*Cancel*");
return;
}
HighlightEntity(vpId, false);
ClipViewport(vpId, polyId);
}
private static ObjectId SelectEntity(Editor ed, Type entityType, string msg)
{
var opt = new PromptEntityOptions(msg);
opt.SetRejectMessage("\nInvalid selection: not a " + entityType.Name);
opt.AddAllowedClass(entityType, true);
var res = ed.GetEntity(opt);
if (res.Status == PromptStatus.OK)
return res.ObjectId;
else
return ObjectId.Null;
}
private static void ClipViewport(ObjectId vpId, ObjectId polyId)
{
using (var tran = vpId.Database.TransactionManager.StartTransaction())
{
var vport = (Viewport)tran.GetObject(vpId, OpenMode.ForWrite);
vport.NonRectClipEntityId = polyId;
vport.NonRectClipOn = true;
tran.Commit();
}
}
private static void HighlightEntity(ObjectId entId, bool highlight)
{
using (var tran = entId.Database.TransactionManager.StartTransaction())
{
var ent = (Entity)tran.GetObject(entId, OpenMode.ForRead);
if (highlight)
ent.Highlight();
else
ent.Unhighlight();
tran.Commit();
}
}
}
}
See this video clip showing the code in action:
HTH
The code I showed basically works in the same way as command VPCLIP. If that is not what you expected, sorry, I am afraid that I do not understand what exactly you want to do.
Sorry, I am afraid that I still do not get what you really need to do. Obviously, VPCLIP command has nothing to do with splitting viewport. By splitting, it probably means change the existing viewport and creating new viewports.Maybe, what you want is to change/remove existing viewports, and/or add new viewports, then apply non-rectangle clips to the viewports. If your goal can be achieved manually, it would also be possibly achieved by code. Unfortunately I simply do not know what is it to do.
If you can post some pictures to show the "Before" and "After" the viewport or viewports look like, it may help others to understand your goal.
Seeing your pictures, I felt a bit more confused: it seems just as simple as creating a non-rectangle viewport, but why you made it sound so differently. Let me try to say what I saw from the pictures what you want to do:
1. in the first picture, it is a layout (paperspace) with a regular viewport, set to "PS" state. That is, through the viewport a polygon in the modelspace can be seen, but not touchable (until the viewport is turned to "MS" state). Here the entity seen in modelspace, be it a polyline or anything else, has nothing to do with what you are to do with viewport.
2. In picture 2, you draw a closed polyline on the layout, which is to be used to clip the only viewport on the layout.
3. in picture 3, you probably issued command VPCLICP, in the execution of the command, you pick the viewport first, then you picked the closed polyline you just drew. when the command is done, the viewport is gone (hidden, not erase, not changed), the polyline is used to show as non-rectangle viewport. and finally, the viewport is in "MS" state (thus, you can touch the entity inModelSpace through the viewport.
See the video below for the process.
So, the code I posted previously is perfectly apply to this case, and it is basically the same as the built-in command "VPCLIP. Thus, I am more confused as to what you really want.
Seeing you said "I am trying to get that details as well, the one which was erased and only clipped version remains.", I'd like remind you: the viewport is NOT ERASED. It is hidden. After clipping, if you select the non-rectangle viewport, in the properties window, you could see actually 2 entities are selected: a viewport and a polyline. that is because the polyline is now associated to the viewport as clipping border.
Sorry, I had hard time to understand you, probably not able to offer any more idea/help.
