On Thu, Apr 18, 2019 at 10:01 AM Roelof Wobben <r.wob...@home.nl> wrote:
> yep, I have read that one
> but I never gets a answer how I can "convert" a point to something like
> north, east
>
> because the challenge wants this to be the answer :
>
> (Dictionary new
> add: 'direction' -> 'north';
> add:
> 'position'
> ->
> (Dictionary new
> add: 'x' -> 0;
> add: 'y' -> 0;
> yourself);
> yourself)
>
If you have previously defined a "representation map", you would be golden.
e.g.
Dictionary new
at: self northDirectionVector put: 'north';
at: self eastDirectionVector put: 'east';
at: self southDirectionVector put: 'south';
at: self westDirectionVector put: 'west';
yourself.
Then:
(Dictionary new
add: 'direction' -> (self directionRepresentationMap at:
self directionVector);
...
>
> and I think I need then to use if then , which I try to avoid as much as
> possible.
>
> Roelof
>
>
>
> Op 18-4-2019 om 18:33 schreef Richard Sargent:
>
> On Thu, Apr 18, 2019 at 8:57 AM Roelof Wobben <r.wob...@home.nl> wrote:
>
>> Hello,
>>
>> I know I have asked earlier but im still stuck on this one :
>> https://github.com/exercism/problem-specifications/blob/master/exercises/robot-simulator/description.md
>>
>> I tried with all double dispatch but that will be a lot of duplicate
>> classes
>>
>> The problem I cannot solve right is that a robot can move or turn. when a
>> robot turns only the direction the robot is facing changes and the position
>> not. when a robot moves the facing direction stays the same but the
>> position changes. but the change is dependend on the facing. Also the new
>> facing direction is dependend on the old facing direction/
>> How can I model this the best.
>>
>> I already have a object Robot that contains the facing direction and the
>> current position
>> or tried without it but then I use a lot of if then's
>>
>>
>> so it there a better way to model this problem so it will be all nice
>> and readable code.
>>
>
> If I remember correctly, Richard O'Keefe gave you a viable design. 1) Use
> a Point for your direction vector. 2) Use a second Point for your position.
>
> e.g. if you align the compass with a Cartesian plane, 0@1 is North, 0@-1
> is South, 1@0 is East, and -1@0 is West. When you move, you add the
> direction vector to your current position. If you allow movements of
> greater than a single unit, you multiply the direction vector by the
> distance before adding that product to the position.
>
>
>> Roelof
>>
>>
>
