Mac OS: make clear that image capture from screen returns an image in premultiplied RGBA format (cont'd).

git-svn-id: file:///fltk/svn/fltk/branches/branch-1.3@9725 ea41ed52-d2ee-0310-a9c1-e6b18d33e121
This commit is contained in:
Manolo Gouy 2012-11-17 14:57:55 +00:00
parent 9adccd6df6
commit 98d5dd690d
1 changed files with 3 additions and 3 deletions

View File

@ -3335,9 +3335,9 @@ static NSBitmapImageRep* rect_to_NSBitmapImageRep(Fl_Window *win, int x, int y,
}
unsigned char *Fl_X::bitmap_from_window_rect(Fl_Window *win, int x, int y, int w, int h, int *bytesPerPixel)
/* Returns a capture of part of a mapped window as a pre-multiplied RGBA array of bytes.
At present, alpha values are always 1 (or 0 for the angles of a window title bar)
because only opaque colors are used to draw, so pre-multiplication can be ignored.
/* Returns a capture of a rectangle of a mapped window as a pre-multiplied RGBA array of bytes.
Alpha values are always 1 (except for the angles of a window title bar)
so pre-multiplication can be ignored.
*bytesPerPixel is always set to the value 4 upon return.
delete[] the returned pointer after use
*/