Keyboard + Mouse

[timeisaparallax]

I'm a graphics programmer working on some OpenGL ES 2 demos for fun / learning of OpenGL. I come from a console and windows background so I've got limited experience with deskop linux environments but plenty of C++ experience.

I'm trying to determine the best way to capture mouse and keyboard input for some minimal interactivity. I see the triangle2 sample opening /dev/input/mouse0 as a file and reading from it to get mouse data. I was aware many things are a file under the hood; is this the suggested approach for reading input in a portable from pi to pi fashion for both mouse and keyboard? A quick google shows me this API is pretty universal for linux. Is it fair to assume doing some googling about this for Debian/Linux will be consistent?


Cheers,
-Bert

[AndyD]

Hi Bert,

I think if you are writing OpenGL ES 2 program then using /dev/input/mouse0 in the same way as hello_triangle2 example is probably the way to go.

For the keyboard you will need to use a different approach. I have some code here that allows you to poll the keyboard.

[PeterO]

Hi Bert,

I think if you are writing OpenGL ES 2 program then using /dev/input/mouse0 in the same way as hello_triangle2 example is probably the way to go.

For the keyboard you will need to use a different approach. I have some code here that allows you to poll the keyboard.

You can access the keyboard in the same way... I have code at home that uses /dev/input fpr mouse, keyboard and a CAD "3D joystick"....

I'll post example code this evening.

You can look in /usr/include/linux/input.h for info on the structres that come out of the /dev/input/ files.

PeterO

[PeterO]

Simple example code in
http://www.peteronion.org.uk/PiProgs/input.c

PeterO

[timeisaparallax]

Ahh thanks Andy and Peter! This will get me moving in the right direction. Looks like I'm going to be doing some header spelunking .

At this point I'm thinking Peter's approach is the way to go. I'm curious what the different character devices at /dev/input/by-id represent. It appears I have 4 variants on the mouse (two of which match the sample regular expression):
-- usb-BTC_USB_Multimedia_Cordless_Kit-if01-event-mouse
-- usb-BTC_USB_Multimedia_Cordless_Kit-event-mouse
-- usb-BTC_USB_Multimedia_Cordless_Kit-mouse
-- usb-BTC_USB_Multimedia_Cordless_Kit-if01-mouse

while I have one keyboard that matches the respective regular expression:
-- usb-BTC_USB_Multimedia_Cordless_Kit-event-kbd

It's interesting since all I have plugged in is a single dongle for both my mouse and keyboard. I'll start spinning on this until I get something working.

Thanks!