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# @markup markdown
# @title 6. wxRuby geometry classes
-->
# 6. wxRuby Geometry classes
## Size (Wx::Size) and position (Wx::Point)
The wxWidgets API has a lot methods that require either `wxSize`, `wxPoint` or both type of value as argument. Although
this can be specified in C++ still relatively concise like
```ruby
new wxFrame(nullptr, -1, "title", wxPoint(0,0), wxSize(500,400))
```
in Ruby this expands to the more verbose
```ruby
Wx::Frame.new(nil, -1, 'title', Wx::Point.new(0,0), Wx::Size.new(500,400))
```
which starts to feel awkward to specify what are in essence just pairs of integers.
To provide a simpler, more compact and more Ruby-like, alternative the wxRuby API therefor supports specifying arrays
of integer pairs in (almost) all cases where `Wx::Size` or `Wx::Point` is expected. So the following code is equivalent
to the previous code:
```ruby
Wx::Frame.new(nil, -1, 'title', [0,0], [500,400])
```
In addition `Wx::Size` and `Wx::Point` support parallel assignment semantics such that you can write code like
```ruby
win.paint do | dc |
# ...
x, y = win.get_position
dc.draw_circle(x, y, 4)
dc.draw_rectangle(x-4, y-4, 8, 8)
end
```
instead of
```ruby
win.paint do | dc |
# ...
pos = win.get_position
dc.draw_circle(pos.x, pos.y, 4)
dc.draw_rectangle(pos.x-4, pos.y-4, 8, 8)
end
```
## Areas (Wx::Rect)
Like `Wx::Size` and `Wx::Point` wxRuby supports parallel assignment for `Wx::Rect` such that you can write code like
```ruby
x, y, width, height = win.get_client_rect
```
Providing arrays of integers as alternative for `Wx::Rect` arguments is not supported as specifying `[0, 0, 20, 40]` is
ambiguous. This could either mean a rectangle with origin `x=0,y=0` and size `width=20,height=40` (`Wx::Rect.new(0,0,20,40)`)
or a rectangle from origin top left `x=0,y=0` to point bottom right `x=20,y=40` (`Wx::Rect.new(Wx::Point.new(0,0), Wx::Point.new(20,40))`).
Version data entries
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