Uninteruptable mouse movement events

[Steam Ranger]

How do I get the mouse position regardless of whether my window is selected or not? I want to get the same kind of coordinates that I get from the report mouse flag, but also get them if a window is selected other than mine.

The ideal solution would be if Intuition could report mouse events to my program, but it would be alright if I had to manually query the mouse position, as long as it always works even when my window is not selected.

[a/b]

Add your interrupt handler to input.device.

[Thomas Richter]

Originally Posted by Steam Ranger

How do I get the mouse position regardless of whether my window is selected or not? I want to get the same kind of coordinates that I get from the report mouse flag, but also get them if a window is selected other than mine.

The mouse position in your window is relative to the window, and thus not relative to all other windows. You can get a mouse position relative to the screen from the screen structure, but that is also only valid if the screen contains the active window. Thus, in a sense, what you request is not exactly possible as users may certainly open more screens, and select active windows on other screens. Since such other screens may be larger or smaller, mouse movement on them may be also scaled differently.


IOWs, while you can possibly get relative mouse movements, you do not get meaningful mouse coordinates without having a window and an input focus.
Thus, please rethink your design - what is it that you need data from the mouse without having the focus?

[Olaf Barthel]

Originally Posted by a/b

Add your interrupt handler to input.device.

Tricky. The raw mouse events which pass through the input handler contain no mouse position information, just movement delta information.

This has to be translated into the respective screen position of where Intuition has currently placed the mouse pointer. You need to find the screen in which the currently active window resides and copy the Screen->MouseX and Screen->MouseY values. For that to work, you ought to use LockIBase() and UnLockIBase() while you are looking for the active screen. And eventually notify your program where the mouse is currently at.

All of this is doable, but easy to get wrong. Calling LockIBase() from within the input handler is strongly discouraged but works most of the time because Intuition was rewritten to allow for it, rather than to deadlock the Intuition state machine (this was easy enough in the Kickstart 1.x days).

Generally, I would not recommend this approach. I would recommend using the simplest possible approach the operating system offers you and adapt your program to make the best of it. This is a multitasking operating system after all. You could try polling your program's Screen->MouseX and Screen->MouseY values by using timer.device. 1/10s intervals should be a good start.

[Steam Ranger]

Originally Posted by Olaf Barthel

Tricky. The raw mouse events which pass through the input handler contain no mouse position information, just movement delta information.

This has to be translated into the respective screen position of where Intuition has currently placed the mouse pointer. You need to find the screen in which the currently active window resides and copy the Screen->MouseX and Screen->MouseY values. For that to work, you ought to use LockIBase() and UnLockIBase() while you are looking for the active screen. And eventually notify your program where the mouse is currently at.

All of this is doable, but easy to get wrong. Calling LockIBase() from within the input handler is strongly discouraged but works most of the time because Intuition was rewritten to allow for it, rather than to deadlock the Intuition state machine (this was easy enough in the Kickstart 1.x days).

Generally, I would not recommend this approach. I would recommend using the simplest possible approach the operating system offers you and adapt your program to make the best of it. This is a multitasking operating system after all. You could try polling your program's Screen->MouseX and Screen->MouseY values by using timer.device. 1/10s intervals should be a good start.

That sounds essentially like what I'm doing in Linux. I'm making my program for Linux and Amiga you see. Currently on Linux my program is informed by XInput whenever the mouse moves, and it manually asks Xlib where the pointer is.

That thing about the screens and active window sounds a bit troublesome though. I think the best way would just be to check MouseX and MouseY every time my library's processing loop is called, and notify the program if it has changed.

[thomas]

Originally Posted by Steam Ranger

regardless of whether my window is selected or not?

So you do have a window? All the other replyers seem to imply that you don't have a window. If you have a window you can read Window->MouseX and MouseY to get the same coordinates you would get from an IntuiMessage. They are kept up to date even if your window is not the active one.

[Steam Ranger]

Originally Posted by thomas

So you do have a window? All the other replyers seem to imply that you don't have a window. If you have a window you can read Window->MouseX and MouseY to get the same coordinates you would get from an IntuiMessage. They are kept up to date even if your window is not the active one.

Are they kept up to date even if the pointer is not on the same screen as my window?

[thomas]

Yes.

[Steam Ranger]

Nice. I'll have to implement a simple test using those to see if they work as I'm expecting.

[Thomas Richter]

Yes, but.... As stated earlier, this information is next to useless if a window on another screen has the focus, and intuition (unlike X) has the concept of screens, and multiple of them can be open at the same time, and the focus being somewhere on a different screen.

Thus, again, what makes you think that you need this information? Screen->MouseX,Y or Window->MouseX,Y may *not* be what you expect them to be, in particular if multiple screens are involved.

[Steam Ranger]

Originally Posted by Thomas Richter

Yes, but.... As stated earlier, this information is next to useless if a window on another screen has the focus, and intuition (unlike X) has the concept of screens, and multiple of them can be open at the same time, and the focus being somewhere on a different screen.

Thus, again, what makes you think that you need this information? Screen->MouseX,Y or Window->MouseX,Y may *not* be what you expect them to be, in particular if multiple screens are involved.

What I expect is a way to get the same information provided by report mouse events, but constantly without any regard to the position of the pointer or the currently active window.

To simplify with an example, something you could use to make xeyes, where if follows your pointer constantly.

[hooverphonique]

Amigas may have multiple screens visible at once, with different resolutions (unlike most other platforms), so I'm not sure that even makes sense - what would the pointer coordinates tell you in such a case?

[Steam Ranger]

Originally Posted by hooverphonique

Amigas may have multiple screens visible at once, with different resolutions (unlike most other platforms), so I'm not sure that even makes sense - what would the pointer coordinates tell you in such a case?

Well the pointer coordinates are relative to the window, so it should still work fine on other screens.

[Thomas Richter]

Originally Posted by Steam Ranger

Well the pointer coordinates are relative to the window, so it should still work fine on other screens.

No, it would not. Once again, mouse positions are scaled according to screen resolutions, and screens (in particular on RTG) have different resolutions. That means that a mouse position relative to a screen that is different from the screen your window is sitting on is next to meaningless. This may be quite irrelevant for toys like Xeyes, but if you use this as a design for more relevant software, things can go quite wrong. You can surely read window->MouseX,Y from your window while it is active, and even without receiving mouse movement events, but when your window is not active, these coordinates are not necessarily in a useful relation to where the mouse pointer actually is. It may be even on a completely different monitor for a two-monitor configuration.

[Steam Ranger]

@thomas Thankyou for pointing me in this direction. MouseX and MouseY work perfectly for my use. Is there anything that modifies its function that I should be aware of?

[Bruce Abbott]

Originally Posted by Steam Ranger

That sounds essentially like what I'm doing in Linux. I'm making my program for Linux and Amiga you see. Currently on Linux my program is informed by XInput whenever the mouse moves, and it manually asks Xlib where the pointer is.

What does your program do that requires knowing the pointer position when another program has the focus?

[Steam Ranger]

Originally Posted by Bruce Abbott

What does your program do that requires knowing the pointer position when another program has the focus?

I'm not making a program per-say, I'm making a library. This is a feature that's required as certain programs may make use of it (xeyes for example).