DC manipulation seems easy until you try to do something with it... I just spend the past 2 weeks.. trying to load an image from memory and create a CBitmap from it... sound easy.. until you try it... Every single function in the GDI or GDI+ wants you to load an image from a "file".. I finally had to use Lead Tools which can easily do this and work for all version of windows.
Anyway... as long as you can get your image loaded into a DC the function that you want to use is: >From MSDN: BOOL StretchBlt( int x, int y, int nWidth, int nHeight, CDC* pSrcDC, int xSrc, int ySrc, int nSrcWidth, int nSrcHeight, DWORD dwRop ); Copies a bitmap from a source rectangle into a destination rectangle, stretching or compressing the bitmap if necessary to fit the dimensions of the destination rectangle. The function uses the stretching mode of the destination device context (set by SetStretchBltMode) to determine how to stretch or compress the bitmap. The StretchBlt function moves the bitmap from the source device given by pSrcDC to the destination device represented by the device-context object whose member function is being called. The xSrc, ySrc, nSrcWidth, and nSrcHeight parameters define the upper-left corner and dimensions of the source rectangle. The x, y, nWidth, and nHeight parameters give the upper-left corner and dimensions of the destination rectangle. The raster operation specified by dwRop defines how the source bitmap and the bits already on the destination device are combined. BTW, I highly recommend Lead Tools if you are going to be doing a lot of DC or Image manipulation. It is will worth the money! ----- Original Message ----- From: "Ehsan Akhgari" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Friday, February 13, 2004 2:13 PM Subject: [msvc] Render a picture on the DC > I'm a kiddie when it comes to DC manipulation, so forgive me if from now on > I seem stupid! > > I need to read an image file (let's say, a .jpg) from disk, and display it > as needed (with resizing depending on the control's dimensions) on my > ActiveX control's DC (windowed control). There's nothing special about > this. And the file format does not matter; it can be .bmp, .gif, .jpg, > .png, anything. > > What I need is a solution that is simple, fast, usable on all versions of > windows, and easy to perform for a DC kiddie. And I need to prepare it as > quickly as I can, because the deadline I have to face is very near. > > I did a search on MSDN, and found lots of information. Many of it looks > good, but I don't have enough knowledge to make a decision on which path to > take, nor do I have enough time to read up on the subject on my own (my > usual method of learning.) > > So is anyone feeling like struggling with a DC newbie? :-) > > Thanks! > ------------- > Ehsan Akhgari > > Farda Technology (www.farda-tech.com) > > List Owner: [EMAIL PROTECTED] > > [ Email: [EMAIL PROTECTED] ] > [ WWW: http://www.beginthread.com/Ehsan ] > > In the mountains the shortest way is from peak to peak, but for that route > you must have long legs. Aphorisms should be peaks, and those spoken to > should be tall and lofty. > -Thus Spoke Zarathustra, F. W. Nietzsche > > > > > _______________________________________________ > msvc mailing list > [EMAIL PROTECTED] > See http://beginthread.com/mailman/listinfo/msvc_beginthread.com for subscription changes, and list archive. >
