C / C++ / MFC

Nishad S11-Dec-05 19:10

11-Dec-05 19:10

Thank you...

I got a little idea. That is, use an image and its filter separately. Filter means transparency of pixels in the image. I think this may be the idea behind the 32bit icons. Am I right?

- NS -

Christian Graus11-Dec-05 19:15

11-Dec-05 19:15

You can set the transparency of a section as you draw it. I don't know of a way to set the transparency differently based on position in the image.

Christian Graus - Microsoft MVP - C++

Nishad S11-Dec-05 19:18

11-Dec-05 19:18

I'm sorry, I don't understand what you meant by section. Could you clarify it, please?

- NS -

Christian Graus11-Dec-05 19:20

11-Dec-05 19:20

When you draw an image, you can specify the transparency for the entire image only, AFAIK. If you draw an image a bit at a time, you could specify transparency for each bit as you draw it.

Christian Graus - Microsoft MVP - C++

Nishad S11-Dec-05 19:27

11-Dec-05 19:27

Oh, I see.

Thank you. Let me try...

But I'm not so sure about what functions I should use for it... Anyway I feel that I can do it... Thank you.

- NS -

Christian Graus11-Dec-05 19:30

11-Dec-05 19:30

If DrawImage doesn't offer it ( it may, in the ImageAttributes class you pass in ), then using a TextureBrush will.

Christian Graus - Microsoft MVP - C++

Nishad S11-Dec-05 19:36

11-Dec-05 19:36

I afraid that you are specifying GDI+ functions. But I was talking about Win32 SDK...

- NS -

Christian Graus11-Dec-05 19:41

11-Dec-05 19:41

Oh, then you're screwed. There's a TransparentBlt, which is probably your best option, and you will almost certainly have to draw the image in sections to specify different transparencies around the edges. W95 is the only OS that does not support TransparentBlt.

Christian Graus - Microsoft MVP - C++

Nishad S11-Dec-05 19:50

11-Dec-05 19:50

Yes... I will try.
I think it can be done by using my own bitmap format in which I can specify the RGB and Transparency for each pixel.

- NS -

TchouTchou Project11-Dec-05 19:50

TchouTchou Project

11-Dec-05 19:50

I'm doing it in my application. Images are draw in real-time using the CxImage library, which offer the transparency function.
You just have to define transparency on image using Paintshoppro for a single image, or jasc animation shop for a animated giff image. then load the image using function of the CxImage libray (transparency is automaticly managed). Then draw the image in you favorite DC.
I use also transform function of the library for rotating and sampling images.
That's a solution.
Good luck.

NKH

Nishad S11-Dec-05 21:59

11-Dec-05 21:59

Could you tell me about getting this library, please?

- NS -

TchouTchou Project11-Dec-05 22:17

TchouTchou Project

11-Dec-05 22:17

This library is available on CodeProject.
Try the keyword Cximage.
There is an exemple in demo file, which show how to use simple functions.
It allows to open many king of image files (jpg, gif, bmp...) and proposes a lot of functions. Quite a little complicated, but if you use only some functions quite great. Thank's to david pizzolato.
For real time display, there are some limitations due to its high computation load, but I didn't find other lib which manages easily transparency.

NKH

Nishad S11-Dec-05 22:21

11-Dec-05 22:21

Yes, I got it... Thank you very much.

- NS -

DeviceIOControl ?

bengoan11-Dec-05 14:11

bengoan

11-Dec-05 14:11

How to use DeviceIOControl to read,wrire ... sector . My teacher asks me for imitating absread,abswite... of Boland C by DeviceIOControl of Visual C .

Thank you a lot

imagic

-- modified at 20:12 Sunday 11th December, 2005

Re: DeviceIOControl ?

kakan12-Dec-05 0:21

kakan

12-Dec-05 0:21

Hello.

You don't need DeviceIOControl to do that.
Just use ordinary functions, like CreateFile, ReadFile, WriteFile, CloseFile and SetFilePointer.

As this is a school-project, I won't give you too much information, but I can tell you this:

1.
The least bit of information you can handle (read, write and seek to) is a disk sector!
A disk sector is (normally) 512 bytes.

2.
You open a volume (unit) by using the name "\\.\<x>:" where <x> is the drive in question.
\\.\A: Opens drive A (floppy drive).
\\.\C: Opens drive C (volume).

3.
All information is available at MSDN (msdn.microsoft.com).

Good luck. The assignment should be fairly easy to accomplish.

Kakan

-- modified at 6:21 Monday 12th December, 2005

Real Time Processing

RKRobinson11-Dec-05 10:18

RKRobinson

11-Dec-05 10:18

Hi
I have written a Reliable Multicast Protocol, which all works fine except that the protocol processing thread and the Media timer used will sometimes stop for up to 400mS which causes a prolem. I have changed thread priorities and Virtual Locked memory to prevent paging delays. I would realy like some suggestions as to the best implementation for this project, should it be written as a standalone process?

TIA
Richard

Re: Real Time Processing

cmk11-Dec-05 10:46

cmk

11-Dec-05 10:46

What are you using the media timer for ?

...cmk

Save the whales - collect the whole set

Re: Real Time Processing

RKRobinson11-Dec-05 11:54

RKRobinson

11-Dec-05 11:54

Hi The media timer is used for process timouts/RTT packet time stamping etc. I had initialy used TimerQueueTimers but found them to be not very acurate at high resolutions.

Re: Real Time Processing

cmk11-Dec-05 20:55

cmk

11-Dec-05 20:55

RKRobinson wrote:
The media timer is used for process timouts/RTT packet time stamping etc.

So you are just using it to get an accurate 'current time' stamp.
I was wondering if you were using it as part of a loop.

I'm sure you realize Win is a preemptive OS - the kernel schedules when threads run.
Any priority boost you specify is taken as a suggestion by the kernel.
There is no real way to guarantee time for a thread.

Currently, the most scalable/responsive I/O systems are built around IOCP (I/O completion ports).

Len Holgate, and others, have written comprehensive articles about IOCP here: http://www.codeproject.com/internet/[^].

...cmk

Save the whales - collect the whole set

WMSyncReader Question

Elbert Mai11-Dec-05 7:47

Elbert Mai

11-Dec-05 7:47

im sorry im really new to the windows media format sdk...

by looking at the WMSyncReader sample that came with the sdk
i have learned how to set up the WMSyncReader and everything
but i still have this question

it seems that WMSyncReader::GetNextSample() uses an INSSBuffer interface
to store audio data when i invoke it.
How can i take the data from an INSSBuffer into, say, a byte array?

Also, how do you get the audio format of the stream? Maybe WMProfile? or WMStreamConfig?

any answers are highly appreciated

thanks!

CString inside CMap

udiraz11-Dec-05 4:23

udiraz

11-Dec-05 4:23

When I wrote:

<code>typedef CMap<CString,CString, int, int > MyType;

MyType myType;
</code>
I got the following error:

error C2440: 'type cast' : cannot convert from 'CString' to 'DWORD_PTR'

do you know why ?

Thanks in advance

Udi Raz

-- modified at 11:03 Sunday 11th December, 2005

RChin11-Dec-05 4:53

RChin

11-Dec-05 4:53

Your declaration is invalid, probably because you have tried to use the <> signs without ticking the 'Ignore HTML tags in this message'.

I Dream of Absolute Zero

udiraz11-Dec-05 5:03

udiraz

11-Dec-05 5:03

OK, Thanks, fixed it..

Udi Raz

RChin11-Dec-05 5:42

RChin

11-Dec-05 5:42

This is just a guess, but I think the message means it cannot convert your CString class to a unique hash key. If you try:

<br />
CMap<CString*, CString*&, int, int&><br />

Then that compiles. You just have to remember to delete your allocated references. It probably uses the object's address as the hash key.

Personally, would use the stl's map class.

I Dream of Absolute Zero