Have you ever wanted to control the mouse cursor from the comfort of your keyboard? With this plugin, you can. While it may not replace the mouse in all situations, there are plenty of cases where one will not have to lift their hands off the keyboard just to nudge the mouse cursor away a little.

Of course, there are a lot more one can do with the plugin than to nudge the cursor! Mouse keys are provided for all four and diagonal movement; mouse buttons; and a unique warping mechanism too. And not only these: the speed of the cursor, the mouse wheel, and that of acceleration can all be configured to match one's desired behaviour.

Using the plugin

To use the plugin, simply include the header in your Sketch, tell the firmware to use the MouseKeys object, and place mouse keys on your keymap. It is best illustrated with an example:

{c++}
#include <Kaleidoscope.h>
#include <Kaleidoscope-MouseKeys.h>
// Somewhere in the keymap:
Key_mouseUp, Key_mouseDn, Key_mouseL, Key_mouseR,
Key_mouseBtnL, Key_mouseBtnR
void setup() {
  Kaleidoscope.use(&MouseKeys);
  Kaleidoscope.setup ();
}

Keys provided by the plugin

The plugin provides a number of keys one can put on the keymap, that allow control of the mouse. They can be divided into a few groups:

Cursor movement

The simplest set of keys are the mouse cursor movement keys. These move the cursor one direction or the other, with speed and acceleration factored in. When a mouse cursor movement key is held down, it will move .speed pixels each .speedDelay milliseconds without acceleration. But when .accelSpeed is non-zero (and it is not zero by default, see below), the speed will increase by .accelSpeed every .accelDelay milliseconds. Thus, unless configured otherwise, holding a direction will move that way at increasing speed.

One can hold more than one key down at the same time, and the cursor will move towards a direction that is the combination of the keys held. For example, holding the "mouse up" and "mouse right" keys together will move the cursor diagonally up and right.

The cursor movement keys are as follows:

Key_mouseUp, Key_mouseDn, Key_mouseL, Key_mouseR: Move the cursor up, down, left, or right, respectively.
Key_mouseUpL, Key_mouseUpR, Key_mouseDnL, Key_mouseDnR: Move the cursor up-left, up-right, down-left, down-right, respectively.

Scroll wheel

Controlling the scroll wheel is similarly simple. It does not have acceleration, but one can control the speed with the .wheelSpeed and .wheelDelay properties (see below).

Key_mouseScrollUp, Key_mouseScrollDn: Scroll the mouse wheel up or down, respectively.

Buttons

Buttons are even simpler than movement: there is no movement speed, nor acceleration involved. One just presses them.

Key_mouseBtnL, Key_mouseBtnM, Key_mouseBtnR: The left, middle, and right mouse buttons, respectively.

Warping

Warping is one of the most interesting features of the plugin, and is a feature unique to Kaleidoscope, as far as we can tell. The warping keys position the mouse cursor within a quadrant of the screen on first press, and any subsequent taps will warp within the previously selected quadrant. For example, pressing the north-west warp key twice will first jump to the middle of the north-west quadrant of your screen, then select the north-west quadrant of that, and jump to the middle of it.

To stop warping, use any other mouse key, or hit the "warp end" key.

This features works out of the box on Windows and OSX. On Linux, a patch exists, but has not been finalised and merged yet.

The warping keys are the following:

Key_mouseWarpNW, Key_mouseWarpNE, Key_mouseWarpSW, Key_mouseWarpSE: Warp towards the north-west, north-east, south-west, or south-east quadrants, respectively.
Key_mouseWarpEnd: End the warping sequence, resetting it to the default state. Using any of the warping keys after this will start from the whole screen again.

Plugin methods

The plugin provides a MouseKeys object, with the following methods and properties available:

`.speed` and `.speedDelay`

These two control the speed of the mouse cursor, when a movement key is held. The former, .speed, controls the amount of pixels the cursor moves, when it has to move, and defaults to 1. The latter, .speedDelay is the amount of time - in milliseconds - to wait between two movements, and defaults to 0, no delay.

`.accelSpeed` and `.accelDelay`

These two properties control the speed of acceleration. The former, .accelSpeed, controls how much the speed shall be increased at each step, while the second, .accelDelay, controls how often (in milliseconds) acceleration should be applied.

They default to 1 pixel and 50 milliseconds, respectively.

`.wheelSpeed` and `.wheelDelay`

The last two properties supported by the plugin control the mouse wheel scrolling speed. The former, .wheelSpeed, controls the amount of ticks the wheel shall scroll, and defaults to 1. The second, .wheelDelay, controls the delay between two scroll events, and defaults to 50 milliseconds.