C / C++ / MFC

Strange error using Case statement

26-Mar-08 6:36

If you really need to store multiple file into yor unique one, you have to copy every file content (possibly each one prefixed by its length).
You may wrap this behaviour into a serializable class (you may call it CFile, oops, no, wait a moment...).
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

piul26-Mar-08 5:14

piul

26-Mar-08 5:14

I'm getting a strange error...
if I write:

if (uType == ANNEAL)
{
  CAnneal * pOrigAnn = dynamic_cast<CAnneal *> (pOrigItem)	;
  if(pOrigAnn != NULL)
  {
     CAnneal * pAnneal = new CAnneal();
  }
...

Everything's fine. But, if I want to use a case instead of an if

switch (uType)
{
  case ANNEAL:
     CAnneal * pOrigAnn = dynamic_cast&lt;CAnneal *&gt; (pOrigItem)	;
     if(pOrigAnn != NULL)
    {
       CAnneal * pAnneal = new CAnneal();
    }
    break;
  case WHATEVER:
...

I get an error that says "initialization of 'pOrigAnn' is skipped by 'default' label" ... "See declaration of pOrigAnn" Confused | :confused:

CPallini26-Mar-08 5:32

26-Mar-08 5:32

Beacause you've not included your code inside a block and pOriginAnn is the whole switch block (while its assignment happens only in ANNEAL case.
You may change it to

switch (uType)
{
  case ANNEAL:
    {
       CAnneal * pOrigAnn = dynamic_cast<CAnneal *> (pOrigItem)	;
       if(pOrigAnn != NULL)
      {
         CAnneal * pAnneal = new CAnneal();
      }
    }
    break;
  case WHATEVER:
...

piul26-Mar-08 5:41

piul

26-Mar-08 5:41

Interesting...
Thank you!!

rp_suman26-Mar-08 5:49

26-Mar-08 5:49

Hi,

So you got the problem..

Thanks,
Suman

rp_suman26-Mar-08 5:35

delete zero out its operand

26-Mar-08 5:35

Hi,

Is there any other access of "pOrigAnn" outside of "case ANNEAL" like:

piul wrote:

switch (uType){
case ANNEAL:
CAnneal * pOrigAnn = dynamic_cast<CAnneal *> (pOrigItem);
if(pOrigAnn != NULL){
CAnneal * pAnneal = new CAnneal();
}
break;
case WHATEVER:...
...
break;
default:
...
}
//access pOrigAnn

or somewhere else?

Thanks,
Suman

George_George26-Mar-08 5:09

George_George

26-Mar-08 5:09

Hello everyone,

A little confused after reading C++ FAQ, "Why doesn't delete zero out its operand?"

http://www.research.att.com/~bs/bs_faq2.html#delete-zero

I think the reason why delete can not zero out its operand is because delete can be operate on rvalue, like

delete f(x);

And we can not assign zero to the rvalue (i.e. delete's operand). My understanding correct?

thanks in advance,
George

Re: delete zero out its operand

CPallini26-Mar-08 5:24

Re: delete zero out its operand

26-Mar-08 5:24

Yes, Bjarne states that clearly.
Smile | :)

George_George26-Mar-08 17:14

George_George

26-Mar-08 17:14

Thanks CPallini,

I think you agree with my understanding. Smile | :)

regards,
George

c++ algorithm to find point inside polygon or not

rp_suman26-Mar-08 5:04

Re: c++ algorithm to find point inside polygon or not

26-Mar-08 5:04

Hi,

I am looking for algorithm which will find the given point is inside of a given polygon(a triangle) or not.
Which will work for coordinate in -ve and +ve direction.

Best Regards,
Suman

BadKarma26-Mar-08 5:53

BadKarma

26-Mar-08 5:53

If you can walk over the lines polygon you should find the point always on the same side either left or right.

Otherwise check out this page[^]

codito ergo sum

Re: c++ algorithm to find point inside polygon or not

CPallini26-Mar-08 5:55

Re: c++ algorithm to find point inside polygon or not

26-Mar-08 5:55

You don't like PtInRegion and CreatePolyRegion functions, do you?

SandipG 26-Mar-08 11:18

SandipG

26-Mar-08 11:18

Re: c++ algorithm to find point inside polygon or not

BadKarma26-Mar-08 21:31

BadKarma

26-Mar-08 21:31

The OP did ask for algorithms and not the functions Poke tongue | ;-P

Maybe i should redirected him, my bad $Shucks | :-\$

To be honest I didn't think of those functions. It has been a long time since I did some GUI stuff.
So thanks for the BrainRefresh Big Grin | :-D

codito ergo sum

Re: c++ algorithm to find point inside polygon or not

rp_suman26-Mar-08 21:49

Re: c++ algorithm to find point inside polygon or not

26-Mar-08 21:49

Hi,

Thanks for help..

How to create the region when the points are not in order and we need to fill the complete region by connecting outermost points using CreatePolyRegion()?

Thanks,
Suman

CPallini26-Mar-08 22:18

Re: c++ algorithm to find point inside polygon or not

26-Mar-08 22:18

Aren't you able to order the points? Is the polygon convex?
Try also the Graphics forum [^].

rp_suman26-Mar-08 22:47

Re: c++ algorithm to find point inside polygon or not

26-Mar-08 22:47

CPallini wrote:
Is the polygon convex?

The polygon can be of any type.
The points may not be in order most of the time.

I will post in Graphics section

Thanks for help!!

Best Regards,
Suman

Saurabh.Garg27-Mar-08 0:02

Saurabh.Garg

27-Mar-08 0:02

You need Convex Hull of points to find a polygon including all points.

-Saurabh

Re: c++ algorithm to find point inside polygon or not

rp_suman2-Apr-08 21:55