My app has an image (black/white tiff) displayed in a picturebox
(scanned text document). I need the user to be able to draw either
white or black rectangles on it. (to hide/cover up sensitive
information, like credit card numbers).
I can do this by loading the file into a graphics object, and then
using the graphics object's methods to do the drawing. The modified
file is then re-displayed on the screen. (by the way, I am using the
MouseDown and MouseUp events to calculate where and how large the
rectangle needs to be)
It works, but there is a few second delay while .NET does all the
processing. Is there a way to do the drawing (click & drag rectangle)
and get INSTANT results? It's frustrating to click and drag the
rectangle, and then wait 5 or so seconds for the rectangle to appear.
This must be possible, because even the most basic graphics
applications allow simple click/drag operations to add shapes to an
image and have INSTANT feedback.
Can anyone shed some light on this?
Thanks!
John