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.
>>
>>
