Re: Is there a way to draw standard controls to bitmap if they aren't on the screen? - C / C++ / MFC Discussion Boards

Re: Generating/exporting a PDF from my MFC application, for reports that are created by overloading OnDraw in a view

Sternocera30-Apr-09 23:55

30-Apr-09 23:55

Rajesh,

I took a look at LibHaru, but I found that it cannot draw to a windows GDI device context...thus, I'd have to rewrite my reports from scratch.

What I'd really like is a drop-in replacement for my GDI device context.

I read somewhere that it is somehow possible to do this using WxWidgets' PDF support. I can't seem to find any more information though,

Regards,
Sternocera

Re: Generating/exporting a PDF from my MFC application, for reports that are created by overloading OnDraw in a view

Rajesh R Subramanian1-May-09 0:01

Rajesh R Subramanian

1-May-09 0:01

You can always create a bitmap of the stuff that's stored on your device context and then Haru can print it to a PDF. Sounds viable?

It is a crappy thing, but it's life -^ Carlo Pallini

Re: Generating/exporting a PDF from my MFC application, for reports that are created by overloading OnDraw in a view

Sternocera1-May-09 0:03

Sternocera

1-May-09 0:03

Rajesh,

Obviously, I'd much rather preserve my reports as vector graphics.

At the moment, I'm looking at wxPdfDocument - It's designed to be used from WxWidgets, but it may be possible to use from MFC,

Regards,
Sternocera

Re: Generating/exporting a PDF from my MFC application, for reports that are created by overloading OnDraw in a view

Rajesh R Subramanian1-May-09 0:11

Rajesh R Subramanian

1-May-09 0:11

If you succeed in making it work with MFC, it must make a good article for CP. Smile | :)

It is a crappy thing, but it's life -^ Carlo Pallini

Re: Generating/exporting a PDF from my MFC application, for reports that are created by overloading OnDraw in a view

Sternocera1-May-09 0:15

Sternocera

1-May-09 0:15

Rajesh,

Yes, indeed. I have a high level idea of how it might be possible.

http://wxcode.sourceforge.net/docs/wxpdfdoc/classwx_pdf_document.html[^]

Look at the function "bool wxPdfDocument::Image". It ought to be possible to export my GDI data to a WMF file ( see http://en.wikipedia.org/wiki/Windows_Metafile[^] ), perhaps to a temp directory, and open that using wxPdfDocument afterwards.

More research is required,

Regards,
Sternocera

Is there a way to draw standard controls to bitmap if they aren't on the screen?

Entrase30-Apr-09 22:04

Entrase

30-Apr-09 22:04

I want to implement drawing of standard listbox, treeview etc. to a layered window. I know there is a method with “fake” layered window under normal one but I need more flexible control on incorporation of standard controls to final image of a layered window.

I think there may be some hidden window with controls I need and whose drawing stuff can be redirected to some bitmap. If it's not possible with the hidden window then what about window that is out of screen (e.g. x = -2000, y = -2000)?

Re: Is there a way to draw standard controls to bitmap if they aren't on the screen?

Code-o-mat30-Apr-09 22:51

Code-o-mat

30-Apr-09 22:51

Try experimenting with WM_PRINTCLIENT[^].

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Life: great graphics, but the gameplay sux. <

Re: Is there a way to draw standard controls to bitmap if they aren't on the screen?

Entrase3-May-09 2:04

Entrase

3-May-09 2:04

Thanks! It works! But there is something wrong with the alpha channel.

[img]http://smages.com/i/0c/74/0c74a1f057b9a7e17a0c27e2b4dd4766.png[/img]

I'm creating 32-bpp bitmap and asking the button do draw itself there with WM_PRINTCLIENT. What's wrong?

hdc = GetDC(hWnd);
hdcMemory = CreateCompatibleDC(hdc);

nBytesPerLine = ((szWin.cx * 32 + 31) & (~31)) >> 3;
stBmpInfoHeader.biSize = sizeof(BITMAPINFOHEADER);
stBmpInfoHeader.biWidth = szWin.cx;
stBmpInfoHeader.biHeight = szWin.cy;
stBmpInfoHeader.biPlanes = 1;
stBmpInfoHeader.biBitCount = 32;
stBmpInfoHeader.biCompression = BI_RGB;
stBmpInfoHeader.biClrUsed = 0;
stBmpInfoHeader.biSizeImage = nBytesPerLine * szWin.cy;

void* pvBits;
hbmpMem = CreateDIBSection(NULL, (PBITMAPINFO)&stBmpInfoHeader, DIB_RGB_COLORS, &pvBits, NULL, 0);
memset(pvBits, 0x88, szWin.cx * szWin.cy * 4);
if (hbmpMem)
{
	HGDIOBJ hbmpOld = SelectObject(hdcMemory, hbmpMem);
	//TextOut(hdcMemory, 10, 10, L"Text", 4);
	SendMessage(ctrl, WM_PRINTCLIENT, (WPARAM)hdcMemory, PRF_CLIENT | PRF_CHILDREN | PRF_OWNED);
	//BitBlt(hdc, 0, 0, szWin.cx, szWin.cy, hdcMemory, 0, 0, SRCCOPY);
	BLENDFUNCTION stBlend;
	stBlend.AlphaFormat = AC_SRC_ALPHA;
	stBlend.BlendFlags = 0;
	stBlend.BlendOp = AC_SRC_OVER;
	stBlend.SourceConstantAlpha = 255;
	//AlphaBlend(hdc, 0, 0, szWin.cx, szWin.cy, hdcMemory, 0, 0, szWin.cx, szWin.cy, stBlend);
	UpdateLayeredWindow(hWnd, hdc, &ptWinPos, &szWin, hdcMemory, &ptSrc, 0, &stBlend, ULW_ALPHA);
	SelectObject(hdcMemory, hbmpOld);
	DeleteObject(hbmpMem);
}
DeleteDC(hdcMemory);
DeleteDC(hdc);

Re: Is there a way to draw standard controls to bitmap if they aren't on the screen?

Code-o-mat3-May-09 2:32

Code-o-mat

3-May-09 2:32

Do you simply want to make a window that has a constant blend factor? Because if yes, then you don't need a bitmap and the fancy drawing and all the rest.
Aside of this, is your problem that the button seems to loose transparency? I supose that's simply because when the button gets drawn onto your bitmap it overwrites the alpha channel.

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Life: great graphics, but the gameplay sux. <

Re: Is there a way to draw standard controls to bitmap if they aren't on the screen?

Entrase4-May-09 2:30

Entrase

4-May-09 2:30

I do need per-pixel alpha for some skinning engine Smile | :)

So if control overrides alpha then I have to make one more bitmap (24 bpp) and then blit it to my 32b buffer? Or there is simpler solution?

Re: Is there a way to draw standard controls to bitmap if they aren't on the screen?

Code-o-mat4-May-09 2:33

Code-o-mat

4-May-09 2:33

How about filling the alpha channel after you rendered your controls?

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Life: great graphics, but the gameplay sux. <

Check for empty buffer

CodingLover30-Apr-09 18:49

CodingLover

30-Apr-09 18:49

Hi All,

On a TCHAR buffer I've some data. I want to check them either empty or not, the content.

I tried this.

<br />
TCHAR szMyBuffer[128];<br />
<br />
if(szMyBuffer != L"")<br />
   // Do the process<br />

But this is not work, what can I do on that?

Thanks a lot

I appreciate your help all the time...
CodingLover Smile | :)

Re: Check for empty buffer

Joe Woodbury30-Apr-09 19:15

Joe Woodbury

30-Apr-09 19:15

You are checking the address of the buffer, you need to check the contents. Try:

~~if (!szMyBuffer[0])~~

if (szMyBuffer[0])

(Sorry for the brain freeze.)

Anyone who thinks he has a better idea of what's good for people than people do is a swine.
- P.J. O'Rourke

Re: Check for empty buffer

CPallini30-Apr-09 23:00

CPallini

30-Apr-09 23:00

It's quite the opposite (i.e. if (szMyBuffer[0])).
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

[My articles]

Re: Check for empty buffer

Rajesh R Subramanian30-Apr-09 23:40

Rajesh R Subramanian

30-Apr-09 23:40

Well, you both are right, it is a matter of "where" you handle the error. Some people go by that style, Carlo. Smile | :)

It is a crappy thing, but it's life -^ Carlo Pallini

Re: Check for empty buffer

CPallini30-Apr-09 23:47

CPallini

30-Apr-09 23:47

Rajesh R Subramanian wrote:
Some people go by that style, Carlo.

I use that style too. However, OP was asking for

if(szMyBuffer != L"")
// Do the process

replacement.

--Carlo the Nitpick.
Smile | :)

Re: Check for empty buffer

Rajesh R Subramanian30-Apr-09 23:57

Rajesh R Subramanian

30-Apr-09 23:57

I agree, but he might have meant to handle the error with if and write the processing code into else. Just that he wasn't clear with it.

But OK, you win today. Laugh | :laugh:

It is a crappy thing, but it's life -^ Carlo Pallini

Re: Check for empty buffer

Fernando A. Gomez F.30-Apr-09 19:55

Fernando A. Gomez F.

30-Apr-09 19:55

You could also try

if (_tcslen(szMyBuffer) > 0)
   // do the process

About _tcslen[^]

Stupidity is an International Association - Enrique Jardiel Poncela

Re: Check for empty buffer

Joe Woodbury3-May-09 14:17

Joe Woodbury

3-May-09 14:17

I hate that construct. Why do a CRT call when all that matters is the first character?

Anyone who thinks he has a better idea of what's good for people than people do is a swine.
- P.J. O'Rourke

Re: Check for empty buffer

Fernando A. Gomez F.3-May-09 17:47

Fernando A. Gomez F.

3-May-09 17:47

Personally, because it's clearer to read. I gave another option, and so did others. Let the OP decide.

Stupidity is an International Association - Enrique Jardiel Poncela

Re: Check for empty buffer

Eytukan30-Apr-09 20:28

Eytukan

30-Apr-09 20:28

CodingLover wrote:
if(szMyBuffer != L"")

As Joe said, this isn't the buffer itself. You cannot check using the == operator.
If you are using std::string or CString, you could. That too I'd prefer checking their lengths. For buffers you could use CRT routines :
MSDN[^]

Starting to think people post kid pics in their profiles because that was the last time they were cute - Jeremy.

Re: Check for empty buffer

CPallini30-Apr-09 22:58

CPallini

30-Apr-09 22:58

if (*szMyBuffer)
// Do the process

Convert Ascii to hex.and hex to decimal.

Le@rner30-Apr-09 18:39

Le@rner

30-Apr-09 18:39

Hi all,

i have an ascii value in unsigned char* buffer, i want to convert it in Hex.

please tell me how can i convert it in hex.

and i also want to convert hex values in decimal .

so please tell me how can i do this.

thanks in advance.

To accomplish great things, we must not only act, but also dream;
not only plan, but also believe.

Re: Convert Ascii to hex.and hex to decimal.

Rajesh R Subramanian30-Apr-09 20:47

Rajesh R Subramanian

30-Apr-09 20:47

If you are using CString, then you haven't read my previous reply to you, a few days ago: printf tutorial for you[^]

If you are not using MFC, still still MUST read the printf tutorial and you can use _stprintf[^]

It is a crappy thing, but it's life -^ Carlo Pallini

Re: Convert Ascii to hex.and hex to decimal.

Le@rner30-Apr-09 20:49

Le@rner

30-Apr-09 20:49

thanks

To accomplish great things, we must not only act, but also dream;
not only plan, but also believe.

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.