🚀 go-pugleaf

"saravanan" <asaravanan@ften.com> wrote in message
news:441516f5$1@newsgroups.borland.com...

>   Consider i have 5 windows in my application and only 3 of
> them requires painting, in this case i will try to paint all the 5
windows.

Then you need to selectively choose which forms to repaint, instead of
repainting all of them unconditionally.  If you only have 5, then hard-code
the pointers instead of using a loop:.

    void __fastcall UpdateAppropriateForms()
    {
        Form1->Update();
        Form3->Update();
        Form5->Update();
    }

    void __fastcall TForm1::Function()
    {
        Operation1();
        UpdateAppropriateForms();

        Operation2();
        UpdateAppropriateForms();

        Operation3();
        UpdateAppropriateForms();
    }


Otherwise, you'll have to set up some kind of list that the loop can use to
decide which forms to repaint, ie:

    void __fastcall UpdateForms(TForm **Forms, int FormCountHigh)
    {
        for(int i = 0; i <= FormCountHigh; ++i)
            Forms[i]->Update();
    }

    void __fastcall TForm1::Function()
    {
        Operation1();
        UpdateForms( OPENARRAY(TForm, (Form1, Form3, Form5)) );

        Operation2();
        UpdateForms( OPENARRAY(TForm, (Form2, Form4)) );

        Operation3();
        UpdateForms(OPENARRAY(TForm, (Form1)) );
    }


> Already OS is taking care of painting the necessary area only, i think
> we are ignoring that optimization or performance.

Not true.  Update() only repaints the areas that actually need repainting,
in other words the areas that have pending WM_PAINT and related messages
already in the message queue.  Repaint() on the other hand, is a full
repainting regardless of the current queue status.


Gambit