Reputation: 331
On this page : https://learn.microsoft.com/en-us/windows/win32/gdi/wm-ncpaint it is explained how to draw in the nonclient area with GDI.
How can I draw in the nonclient area of my window with Direct2D without having to deal with GDI or GDI+ ?
Upvotes: 1
Views: 1381
Reputation: 1420
First of all, WM_NCPAINT
is old. Using it will disable the DWM theme-ing for the window, giving a windows classic/7 basic look. So don't do it.
But to use any rendering API do draw in the client area, remove the standard window frame from the window by returning 0 when wParam is true in your WM_NCCALCSIZE
message.
case WM_NCCALCSIZE:
if (static_cast<bool>(wParam))
return 0;
return DefWindowProc(hwnd, msg, wParam, lParam);
If you want to keep the standard borders, recalculate the window bounds in WM_NCCALCSIZE
.
Then to get a "client area" title bar, use DwmExtendFrameIntoClientArea
and extend it from the TOP
.
Make sure to handle WM_NCHITTEST
so that dragging your window will work too.
Make sure to premultiply your ALPHA
in direct2d.
Drawing a rectangle at (0,0) will draw a rectangle in the titlebar of your new custom window.
SEE: https://github.com/oberth/custom-chrome
Upvotes: 2