Find Pixel value in picture control to draw a graph

Question

I am creating a project similar to task manager,

Now I want to draw a graph to that show cpu usage.

My problem is that I dont have any knowledge about painting in vc++, but my idea is that I should first make a grid like in task manager but I dont have any pixel information, So plese tell me how to find the pixel value if the Picture control.

Answer 1

Rather than trying to manipulate what's on screen what you need to do is a create a bitmap in memory using CBitmap::CreateCompatibleBitmap and BitBlt when Windows sends a WM_PAINT message.

This question looks at how to subclass a CStatic control (ie a picture control) to draw onto a dialog by handling WM_PAINT messages: Handling WM_PAINT in a Subclassed CStatic Control

You just need to add the bitmap painting bit.