Ah interesting, that makes sense. Wasn't sure if I could const it while
changing the contents.
Would it be possible to run the callback when I init a "mouse" object? I
feel like it should be possible but I can't seem to figure out how to
reference or pointer the object being initialized from within it's own
constructor. Similar to the below, replacing thisObject for something?
type Mouse
position
function Mouse(window)
position = (0.0,0.0)
GLFW.SetCursorPosCallback(window, (x,y)->thisObject.position = (x,y
))
new(position)
end
end
On Thursday, May 7, 2015 at 3:32:01 AM UTC-4, Alex wrote:
>
> You could put the whole code into a function main() if you want. If you
> have a fixed set of Foos you can also declare them const (`const foo =
> Foo(0.,0.), since you would only change the fields in foo.
>
> - Alex.
>
> On Thursday, 7 May 2015 09:22:00 UTC+2, Elburz Sorkhabi wrote:
>>
>> Thanks for the insight, very much appreciated.
>>
>> I had considered doing something similar with a type, but what that be on
>> par with global variables in terms of performance? I read in the docs that
>> global variables are frowned up.
>>
>> On Thursday, May 7, 2015 at 3:15:28 AM UTC-4, Alex wrote:
>>>
>>> Hi!
>>>
>>> Strangely enough (?) it seems one can't pass normal functions
>>> to GLFW.Set...Callback. But if you just want to store the positions in some
>>> object (maybe to change its properties) you can do something like this
>>>
>>> # some type which needs positions
>>> type Foo
>>> x::Float64
>>> y::Float64
>>> end
>>>
>>> setpos!(foo::Foo, x, y ) = (foo.x = x; foo.y = y; foo)
>>>
>>> # initialize a Foo
>>> foo = Foo(0.,0.)
>>>
>>>
>>> # this is the callback function which updates the coordinates in foo
>>> function poscb(foo::Foo, x, y)
>>> println("cursor pos: $x, $y")
>>>
>>> setpos!(foo, x, y)
>>>
>>> nothing
>>> end
>>>
>>>
>>> # ...
>>>
>>>
>>> GLFW.SetCursorPosCallback(window, (x,y)->poscb(foo, x,y))
>>>
>>>
>>> # ...
>>>
>>> In the main loop you can now draw/use foo with updated positions.
>>>
>>> Hope it helps,
>>>
>>> Alex.
>>>
>>> PS: The question about the Julian way of doing event
>>> processing/callbacks is quite interesting. Reactive.jl is pretty cool, but
>>> I don't know if there is a "consensus" that it is the recommended or
>>> preferred way of doing this.
>>>
>>>
>>> On Wednesday, 6 May 2015 22:49:00 UTC+2, Elburz Sorkhabi wrote:
>>>>
>>>> Hey there, about a week into Julia now and really enjoying it.
>>>>
>>>> I have a quick question that I feel is pretty simple but I can't seem
>>>> to find any good examples in the docs or by looking through other peoples
>>>> code, and I'm quite new to programming callbacks in general.
>>>>
>>>> I'm trying to get keyboard and mouse inputs from this GLFW.jl saved
>>>> into a variable:
>>>>
>>>> https://github.com/JuliaGL/GLFW.jl/blob/master/examples/callbacks.jl
>>>>
>>>> In this example callbacks are used to update and println() the values.
>>>> I tried a few different things like replacing the println() with another
>>>> function that would assign the values to some variables, as well as just
>>>> assigning variables after the ->, but I must be missing something simple
>>>> as
>>>> those didn't seem to work properly.
>>>>
>>>> What I'd really like is to be able to write something like :
>>>>
>>>> mouseCoordinates = GLFW.SetCursorPosCallback(window, (x, y))
>>>>
>>>> and have a 2 element set with the x and y position easily accessible.
>>>>
>>>> For reference here is the implementation of the SetCursorPosCallback
>>>> function (near the bottom of this page):
>>>>
>>>> https://github.com/JuliaGL/GLFW.jl/blob/master/src/glfw3.jl
>>>>
>>>> And what seems to be happening is that the function is being passed
>>>> into a macro here:
>>>>
>>>> https://github.com/JuliaGL/GLFW.jl/blob/master/src/util.jl
>>>>
>>>> Any help even just walking me through it would be greatly appreciated.
>>>>
>>>>
