Any way to make touch screen act like a touchpad?

FordNoMore · 06-01-2008, 01:44 AM

So I'm looking all over my dash for a spot to mount a touch pad, and then it dawns on me that there's this huge 7" touch screen staring me in the face that's already beautifully mounted... Is there any way to switch the screen from acting like a regular touch screen to acting like touch pad, where the mouse arrow doesn't immediately jump to your finger, but instead just responds to the relative motions?

For digitizers and tablets I believe this is called switching from "Absolute Mode" to "Relative Mode".

A touch screen is great for clicking on big buttons to do things. But sometimes you need better precision like you'd get with a mouse or touchpad. Despite how tiny the screen is compared to a regular desktop, when I'm using a mouse I have no problem clicking on menus or small buttons that are practically impossible to hit with my finger on the touch screen.

I don't know how you'd trigger the switching between modes... There could be a button you click, or a place on the touchscreen you press and hold, or it could even just be related to which program you're using.

Has this been done? Anyone else think it would be useful? Any ideas how to pull it off?

FordNoMore · 06-01-2008, 10:59 PM

Okay, so 2nd best would be a "virtual touchpad" or "on-screen touchpad" program. Oddly enough I found a patent for just this idea (claim 12 about halfway down) but I'm coming up dry for any actual programs.

blackcobra487 · 06-04-2008, 02:52 AM

I'm unsure of what it is you wish to accomplish. I know there are setting for my touchscreen drivers that can change it's click behavior. Other than that, I don't see how a touch screen doesn't act like a touchpad already.

Edit: After re-thinking, I do know what you mean by "relative motions" but don't really see why you would want this. Except if you where trying to put a certain window on a second monitor, or trying to click on something on another monitor.

eric_barcus · 06-04-2008, 11:10 AM

Your talking about relitive like this right? where the dark grey area would be a "pre defined" location that would act like a touchpad

FordNoMore · 06-04-2008, 09:19 PM

Yeah, that's sort of the option I mentioned in my 2nd post above. And maybe that dark square would be its own little application window that looks like a touchpad, which you could drag around the screen, just like the Windows on-screen keyboard.

Maybe I didn't explain the first idea so well though... For stuff like Road Runner the regular touch screen is awesome. You just touch buttons on the screen and they depress. All is well.

But then you run a normal app like Firefox or Word or even Windows Control Panel. Now you have to access tiny little buttons, pick items off of a drop-down menu, etc. Does not work well on a touch screen. Normally I'd use a mouse or a touch pad for this work.

But, if I could switch the screen into an alternate mode and make the whole thing act like a touch pad, that would be great. I could just touch it anywhere and drag my finger around to move the mouse arrow precisely, just like I would on a touch pad. Rather than define a certain area or window that acts like a touch pad, the whole screen could go into "touch pad" or "relative" mode.

To clarify for BlackCobra: When you touch a touch screen, the mouse arrow jumps to where your finger is. When you use a touch pad (like the ones on most laptop computers), the mouse arrow moves in the direction you move your finger, but if you lift up your finger and put it down somewhere else, the arrow does not move. This allows very fine control.

Anyway, lots of people seem to have both a touch screen and a touch pad (that was my plan) because sometimes one is better than the other, but it'd be awesome if you could just switch modes on the touch screen and then it's all you need.

I'm thinking I should drop a post in Software Development, because that's probably where all the savvy programmers hang out.

EDIT: Okay, I don't want to contribute to duplicate thread pollution, so instead, Mod's, could you move this to Software Development?

eric_barcus · 06-04-2008, 10:02 PM

i think its an awesome idea! and i think you might be able to get a script for it it be nice to see a "floating button" that could sit in the corner of your screen and then when you clicked it you got a transparent gray overlay box (like in my drawing) that you could use to add to the current x,y coordinates of the mouse cursor so lets say the script would do this

(upon activating the "Transparent box")
the script would read the mouse coordinates
then when your finger was in side the transarent box perimeters (defined like other RR settings starting with X,Y,W,H)
it would add to the X,Y coordinates of the current mouse location

dont knwo how to right the script but

Code:

Get current mouse position as VAR MOUSE
IF transparent box is visable
then ADDTOCURSERCODE() is called

ADDTOCURSERCODE()
MOUSE + movement inside of transparent area

(wow that has to be this ****tyest looking code ive ever written, im jsut goint to

at it )

it would be cool if the box was draggable around the screen by one of its corners

i wonder if we could make this work... can a mod move this to the software development forum if FordNoMore aggrees?

FordNoMore · 06-04-2008, 10:36 PM

Yeah, the algorithm shouldn't be hard. It's hooking into Windows, stealing touch screen input, tweaking it, and spitting it back at the OS that would take me some research.

To any other programmers passing through, here's maybe a head start: http://msdn.microsoft.com/en-us/libr...8VS.85%29.aspx

This talks about how to register a program for raw input. Apparently you can register a program to receive constant HID raw input even when it doesn't have the focus. Typically you'd pass the raw input on to DefRawInputProc, so I'm thinking this might be our chance to intervene. If we can read the raw touch screen input, interpret it and cook up our own "raw input" to pass on to DefRawInputProc, that might be the ticket.

blackcobra487 · 06-05-2008, 01:50 PM

Alright, I see what you're getting at. I really like the idea. Let me know if it happens for you.