Drawing Graphs using GDI

Question

I am trying to create a similar kind of graph in the below mentioned image .

I have managed to create the something similar to that. But now I want to implement Scaling. How can implement exact sales to fit those 2 points?

---

Adeel

Answer 1

I think you could draw your 3 colored zone in a memory buffer and associated this buffer to graphical Interface thanks to CreateDIBSection, add texts around your graphe .

To implement Scaling use the StretchBlt function to resize the image and add units texts around your graph with adpated scale to good repositionning it.

---

Delphine GARRO

Answer 2

Thanks can you show me an example where StretchBlt is used to create Scales?

---

Adeel

Answer 3

	HDC				hDisplayObject;

	hDisplayObject = CreateCompatibleDC( NULL);

	SelectObject( hDisplayObject, HandleFullDraw );
	::StretchBlt(Context, x_OnScreen, y_OnScreen, NewWidth,NewHeight,hDisplayObject, 0, 0, RealWidth,RealHeight, SRCCOPY );

	DeleteDC( hDisplayObject ); 

---

Delphine GARRO

Answer 4

	HDC				hDisplayObject;

	hDisplayObject = CreateCompatibleDC( NULL);

	SelectObject( hDisplayObject, HandleFullDraw );
	::StretchBlt(Context, x_OnScreen, y_OnScreen, NewWidth,NewHeight,hDisplayObject, 0, 0, RealWidth,RealHeight, SRCCOPY );

	DeleteDC( hDisplayObject ); 

---

Delphine GARRO

Thanks what is HandleFullDraw in this case?

---

Adeel

Answer 5

	#define 		BYTES_PER_PIXEL_VIDEO	4

	HDC						hdc;
	int						NbPixels, L, H;
	DWORD						*CouleurImage, CouleurDeFond;
    	BITMAPINFO 					EnteteBitmap;// bitmap header

	HANDLE						HandleFullDraw;
	VOID						*ptrPixelImageGRAPHE;



	L=1024;
	H=600;

	NbPixels= L*H;

	hdc = CreateCompatibleDC(NULL);

	ZeroMemory(&EnteteBitmap, sizeof(BITMAPINFO));

	EnteteBitmap.bmiHeader.biSize =				sizeof(BITMAPINFOHEADER);
	EnteteBitmap.bmiHeader.biWidth =			L;
	
	EnteteBitmap.bmiHeader.biHeight =			-H;


	EnteteBitmap.bmiHeader.biPlanes =			1;
	EnteteBitmap.bmiHeader.biBitCount =			8*BYTES_PER_PIXEL_VIDEO;
	EnteteBitmap.bmiHeader.biCompression =		BI_RGB;
	/*32bits par couleurs: 24 bits pour RGB, 8bits pour transparence*/;
	EnteteBitmap.bmiHeader.biSizeImage =		NbPixels * BYTES_PER_PIXEL_VIDEO;

	// create our DIB section and select the bitmap into the dc
	HandleFullDraw = CreateDIBSection(hdc, &EnteteBitmap, DIB_RGB_COLORS, ptrPixelImageGRAPHE, NULL, 0x0);

	CouleurImage=(DWORD*)ptrPixelImageGRAPHE; // Backplane of graph until StrechBlt

	//Modify firt pixel red:
	CouleurImage[0]=RGB( 255,0,0);

---

Delphine GARRO

Answer 6

This isn't really an answer, but an observation.  If you plan to do anything fancy along the way you may save yourself a lot of grief using a package that already does what you want.  There are lots of them, but one for MFC is from Codejock...

Chart Pro

You can do a lot of really nice charting and I think the price is around $200 (not too much programmer time to make that up).

I don't work for Codejock.  Just a customer

:o)

Tom

Answer 7

Hi Adeel,

I marked Delphine's reply as answer, if your issue have not been solved please unmark it and update more information about this issue.

Best regards,
Jesse

---

Jesse Jiang [MSFT]
MSDN Community Support | Feedback to us