Difference between revisions of "Mouse scroll (event)"

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m (Removed the NeedsWork and fixed my own error.)
m (*cough* Apparently, the Event template doesn't allow for more than three return values?)
Line 2: Line 2:
 
|name=mouse_scroll
 
|name=mouse_scroll
 
|desc=Fired when a mousewheel is scrolled in the terminal
 
|desc=Fired when a mousewheel is scrolled in the terminal
|return1=The name of the event.
+
|return1=The direction of the mouse-scroll (<var>-1</var> = up, <var>1</var> = down).
|return2=The direction of the mouse-scroll (<var>-1</var> = up, <var>1</var> = down).
+
|return2=The X-coordinate of the scroll (in screen-characters).
|return3=The X-coordinate of the scroll (in screen-characters).
+
|return3=The Y-coordinate of the scroll (in screen-characters).
|return4=The Y-coordinate of the scroll (in screen-characters).
+
 
|examples=
 
|examples=
 
{{Example
 
{{Example

Revision as of 08:31, 4 May 2013


Grid Modem.png  Event mouse_scroll
Fired when a mousewheel is scrolled in the terminal
Returned Object 1 The direction of the mouse-scroll (-1 = up, 1 = down).
Returned Object 2 The X-coordinate of the scroll (in screen-characters).
Returned Object 3 The Y-coordinate of the scroll (in screen-characters).

Examples

Grid paper.png  Example
Print the direction and the co-ordinates of every mouse scroll we receive a mouse_scroll event for.
Code
while true do
  _, dir, x, y = os.pullEvent("mouse_scroll")
  print("mouse_scroll: " .. tostring(dir) .. ", " ..
    "X: " .. tostring(x) .. ", " ..
    "Y: " .. tostring(y))
end
Output The direction the mouse-wheel was scrolled in, followed by the X and Y position of the event.



Grid paper.png  Example
A variable, i, keeps track of the relative value of the scroll: every time a mouse-scroll occurs, the code checks the direction, incrementing the variable by one for every scroll up and decrementing the variable by one for every scroll down.
Code
i = 0
while true do
   term.clear()
   _, dir, x, y = os.pullEvent("mouse_scroll")
   if dir == -1 then
      i = i + 1
   elseif dir == 1 then
      i = i - 1
   end
   term.setCursorPos(x, y)
   term.write(i)
end
Output At the coordinates of the scroll, the counter value is printed.