Sellam Ismail skrev:
>On Mon, 16 Jul 2001, Tony Duell wrote:
>> > So here's a trick question .. what happens when a person holds
>> > a lightpen to a dark section of the screen. Is the lightpen
>>
>> Nothing happens (literally). The light pen never sees any light, so it
>> can't send a signal to the video card, so the CRT controller can never
>> report the position.
>>
>> > completely blind unless come pixel is lit up?
>>
>> Yes.
>Ok, my mind is still blown. How does a light-pen drawing program work
>then? (Or is a light-pen drawing program not possible?)
The only light pen I've worked with is the Vectrex pen. And while a vector
screen differs somewhat from a CRT (it's non-linear, which doesn't help
decoding), the drawing program simply projected a dot on the screen, which was
moved using the pen. IOW, the dot was registered by the pen, and placing the
pen in any other spot on the screen didn't result in anything, one would have
to move the dot around as a pointer, much like drag-and-drop.
I suppose CRT programs worked the same way.
--
En ligne avec Thor 2.6a.
I can't understand ANY current MICROS~1 product names!
Are they now created with a random word generator?
What is the intent behind the name "Visual Studio" for their compiler suite?
What is "Interdev"?
Why is the Virus Transfer Protocol product named "Outlook"?
Grumpy Ol' Fred
Received on Mon Jul 16 2001 - 19:46:12 BST