dwt learning question,please help

[Frank Benoit]

Denis Koroskin schrieb:
> On Mon, 01 Sep 2008 16:21:12 +0400, Frank Benoit
> <keinfarbton at googlemail.com> wrote:
> 
>> Denis Koroskin Wrote:
>>
>>> On Mon, 01 Sep 2008 12:37:31 +0400, Denis Koroskin <2korden at gmail.com>
>>> wrote:
>>>
>>> > On Mon, 01 Sep 2008 11:32:36 +0400, Frank Benoit
>>> > <keinfarbton at googlemail.com> wrote:
>>> >
>>> >> this code works for me.
>>> >> I will install SP3 to see if i can reproduce the problem.
>>> >
>>> > I have the same bug, too. Windows 2003 Server
>>>
>>> More info:
>>>
>>> Tango backtrace hack intiated
>>> Unhandled D exception!
>>> Error: Array index out of bounds
>>> (tango.core.Exception.ArrayBoundsException) in dwt.graphics.Image [715]
>>> backtrace:
>>>   004d5d51 onArrayBoundsError (+25)
>>>   00404087 void resizeapp.MainForm.InitializeComponents(void*) (+67)
>>> resizeapp.d:32
>>>   00404290 class resizeapp.MainForm resizeapp.MainForm._ctor(void*)�
>>> (+10)
>>> resizeapp.d:79
>>>   004042ab _Dmain (+17) resizeapp.d:86
>>>   004d3041 extern (C) int dmain2.main(int, char**) . void runMain(void*)
>>> (+d)
>>>   004df062 mainCRTStartup (+aa)
>>>   77e6f23c ???
>>>   00000001 ???
>>>
>>> 712 RGB[] rgbs = new RGB[colorPalette.Count];
>>> 713 paletteData = new PaletteData(rgbs);
>>> 714 for (int i = 0; i < colorPalette.Count; i++) {
>>> 715     if (((palette.Entries[i] >> 24) & 0xFF) is 0 &&
>>> (colorPalette.Flags & Gdip.PaletteFlagsHasAlpha) !is 0) {
>>> 716         transparentPixel = i;
>>> 717     }
>>> 718     rgbs[i] = new RGB(((palette.Entries[i] & 0xFF0000) >> 16),
>>> ((palette.Entries[i] & 0xFF00) >> 8), ((palette.Entries[i] & 0xFF) >>
>>> 0));
>>> 719 }
>>> 720 OS.HeapFree(hHeap, 0, palette);
>>> 721 break;
>>
>>
>> This was fixed in
>> http://www.dsource.org/projects/dwt-win/changeset/302%3A555d58850cd9
>> can you please retry with the newest tip version?
>> http://hg.dsource.org/projects/dwt-win/archive/tip.zip
>>
>> Frank
> 
> Ouch! Are you sure this fixes the issue and not hides it? It's quite
> clear that the bug is somewhere else, colorPalette.Count ==
> palette.Entries should always evaluate to true.

you mean
colorPalette.Count == palette.Entries.length
?

I think this is not true. It would be true if Entries would be an
dynamic array. But it is static array, hence the length is always 1.
But the real array /can/ be longer.

struct ColorPalette {
  int Flags;
  int Count;
  int[1] Entries;
}

To avoid the array bounds check i changed the code to use the pointer
arithmetic.

Does that make sense?