Class | Rubygame::Rect |
In: |
ext/rubygame/rubygame_mixer.c
lib/rubygame/rect.rb |
Parent: | Array |
A Rect is a representation of a rectangle, with four core attributes (x offset, y offset, width, and height) and a variety of functions for manipulating and accessing these attributes.
Like all coordinates in Rubygame (and its base library, SDL), x and y offsets are measured from the top-left corner of the screen, with greater y offsets being lower. Thus, specifying the x and y offsets of the Rect is equivalent to setting the location of its top-left corner.
In Rubygame, Rects are used for collision detection and describing the area of a Surface to operate on.
Create a new Rect, attempting to extract its own information from the given arguments. The arguments must fall into one of these cases:
- 4 integers +(x, y, w, h)+. - 1 Rect or Array containing 4 integers +([x, y, w, h])+. - 2 Arrays containing 2 integers each +([x,y], [w,h])+. - 1 object with a +rect+ attribute which is a valid Rect object.
All rect core attributes (x,y,w,h) must be integers.
# File lib/rubygame/rect.rb, line 86 def initialize(*argv) case argv.length when 1 if argv[0].kind_of? Array; super(argv[0]) elsif argv[0].respond_to? :rect; super(argv[0]) end when 2 super(argv[0].concat(argv[1])) when 4 super(argv) end return self end
Extract or generate a Rect from the given object, if possible, using the following process:
1. If it's a Rect already, return a duplicate Rect. 2. Elsif it's an Array with at least 4 values, make a Rect from it. 3. Elsif it has a +rect+ attribute., perform (1) and (2) on that. 4. Otherwise, raise TypeError.
See also Surface#make_rect()
# File lib/rubygame/rect.rb, line 109 def Rect.new_from_object(object) case(object) when Rect return object.dup when Array if object.length >= 4 return Rect.new(object) else raise(ArgumentError,"Array does not have enough indices to be made into a Rect (%d for 4)."%object.length ) end else begin case(object.rect) when Rect return object.rect.dup when Array if object.rect.length >= 4 return Rect.new(object.rect) else raise(ArgumentError,"Array does not have enough indices to be made into a Rect (%d for 4)."%object.rect.length ) end end # case object.rect rescue NoMethodError # if no rect.rect raise(TypeError,"Object must be a Rect or Array [x,y,w,h], or have an attribute called 'rect'. (Got %s instance.)"%object.class) end end # case object end
Set the x and y coordinates of the bottom-left corner of the Rect by translating the Rect (adjusting the x and y offsets).
# File lib/rubygame/rect.rb, line 280 def bottomleft=(bottomleft) raise ArgumentError, "Rect#bottomleft= takes an Array of form [x, y]." if bottomleft.size != 2 self[0], self.bottom = bottomleft return bottomleft end
Set the x and y coordinates of the bottom-right corner of the Rect by translating the Rect (adjusting the x and y offsets).
# File lib/rubygame/rect.rb, line 294 def bottomright=(bottomright) raise ArgumentError, "Rect#bottomright= takes an Array of form [x, y]." if bottomright.size != 2 self.right, self.bottom = bottomright return bottomright end
Set the x and y coordinates of the center of the Rect by translating the Rect (adjusting the x and y offsets).
# File lib/rubygame/rect.rb, line 219 def center=(center) raise ArgumentError, "Rect#center= takes an Array of the form [x,y]." if center.size != 2 self.centerx, self.centery = center center end
Translate the calling Rect to be entirely inside the given Rect. If the caller is too large along either axis to fit in the given rect, it is centered with respect to the given rect, along that axis.
# File lib/rubygame/rect.rb, line 376 def clamp!(rect) nself = self.normalize rect = Rect.new_from_object(rect) #If self is inside given, there is no need to move self unless rect.contain?(nself) #If self is too wide: if nself.at(2) >= rect.at(2) self[0] = rect.centerx - nself.at(2).div(2) #Else self is not too wide else #If self is to the left of arg if nself.at(0) < rect.at(0) self[0] = rect.at(0) #If self is to the right of arg elsif nself.right > rect.right self[0] = rect.right - nself.at(2) #Otherwise, leave x alone end end #If self is too tall: if nself.at(3) >= rect.at(3) self[1] = rect.centery - nself.at(3).div(2) #Else self is not too tall else #If self is above arg if nself.at(1) < rect.at(1) self[1] = rect.at(1) #If self below arg elsif nself.bottom > rect.bottom self[1] = rect.bottom - nself.at(3) #Otherwise, leave y alone end end end return self end
Crop the calling Rect to be entirely inside the given Rect. If the caller does not intersect the given Rect at all, its width and height are set to zero, but its x and y offsets are not changed.
As a side effect, the Rect is normalized.
# File lib/rubygame/rect.rb, line 425 def clip!(rect) nself = self.normalize other = Rect.new_from_object(rect).normalize! if self.collide_rect?(other) self[0] = [nself.at(0), other.at(0)].max self[1] = [nself.at(1), other.at(1)].max self[2] = [nself.right, other.right].min - self.at(0) self[3] = [nself.bottom, other.bottom].min - self.at(1) else #if they do not intersect at all: self[0], self[1] = nself.topleft self[2], self[3] = 0, 0 end return self end
Iterate through all elements in the given Array, and return the index of the first element which is a Rect that collides with the caller.
# File lib/rubygame/rect.rb, line 468 def collide_array(array_rects) for i in (0...(array_rects.length)) if array_rects[i].collide_rect?(self) return i end end return nil end
Iterate through all elements in the given Array, and return an Array containing the indices of every element that is a Rect that collides with the caller.
# File lib/rubygame/rect.rb, line 480 def collide_array_all(array_rects) indexes = [] for i in (0...(array_rects.length)) if array_rects[i].collide_rect?(self) indexes += [i] end end return indexes end
Iterate through all key/value pairs in the given hash table, and return the first pair whose value is a Rect that collides with the caller.
Because a hash table is unordered, you should not expect any particular Rect to be returned first.
# File lib/rubygame/rect.rb, line 446 def collide_hash(hash_rects) hash_rects.each { |key,value| if value.collide_rect?+(self); return [key,value]; end } return nil end
Iterate through all key/value pairs in the given hash table, and return an Array of every pair whose value is a Rect that collides the caller.
Because a hash table is unordered, you should not expect the returned pairs to be in any particular order.
# File lib/rubygame/rect.rb, line 459 def collide_hash_all(hash_rects) hash_rects.select { |key,value| value.collide_rect?+(self) } end
True if the point is inside (including on the border) of the caller. If you have Array of coordinates, you can use collide_point?(*coords).
# File lib/rubygame/rect.rb, line 492 def collide_point?(x,y) nself = normalize() x.between?(nself.left,nself.right) && y.between?(nself.top,nself.bottom) end
True if the caller and the given Rect overlap (or touch) at all.
# File lib/rubygame/rect.rb, line 498 def collide_rect?(rect) nself = self.normalize rect = Rect.new_from_object(rect).normalize! return ((nself.l >= rect.l && nself.l <= rect.r) or (rect.l >= nself.l && rect.l <= nself.r)) && ((nself.t >= rect.t && nself.t <= rect.b) or (rect.t >= nself.t && rect.t <= nself.b)) end
True if the given Rect is totally within the caller. Borders may overlap.
# File lib/rubygame/rect.rb, line 507 def contain?(rect) nself = self.normalize rect = Rect.new_from_object(rect).normalize! return (nself.left <= rect.left and rect.right <= nself.right and nself.top <= rect.top and rect.bottom <= nself.bottom) end
Increase the Rect‘s size is the x and y directions, while keeping the same center point. For best results, expand by an even number. X and y inflation can be given as an Array or as separate values.
# File lib/rubygame/rect.rb, line 525 def inflate!(x,y) self[0] -= x.div(2) self[1] -= y.div(2) self[2] += x self[3] += y return self end
Set the x and y coordinates of the midpoint on the bottom side of the Rect by translating the Rect (adjusting the x and y offsets).
# File lib/rubygame/rect.rb, line 354 def midbottom=(midbottom) raise ArgumentError, "Rect#midbottom= takes an Array of form [x, y]." if midbottom.size != 2 self.centerx, self.bottom = midbottom return midbottom end
Set the x and y coordinates of the midpoint on the left side of the Rect by translating the Rect (adjusting the x and y offsets).
# File lib/rubygame/rect.rb, line 309 def midleft=(midleft) raise ArgumentError, "Rect#midleft= takes an Array of form [x, y]." if midleft.size != 2 self[0], self.centery = midleft return midleft end
Set the x and y coordinates of the midpoint on the right side of the Rect by translating the Rect (adjusting the x and y offsets).
# File lib/rubygame/rect.rb, line 339 def midright=(midright) raise ArgumentError, "Rect#midright= takes an Array of form [x, y]." if midright.size != 2 self.right, self.centery = midright return midright end
Set the x and y coordinates of the midpoint on the top side of the Rect by translating the Rect (adjusting the x and y offsets).
# File lib/rubygame/rect.rb, line 324 def midtop=(midtop) raise ArgumentError, "Rect#midtop= takes an Array of form [x, y]." if midtop.size != 2 self.centerx, self[1] = midtop return midtop end
Fix Rects that have negative width or height, without changing the area it represents. Has no effect on Rects with non-negative width and height. Some Rect methods will automatically normalize the Rect.
# File lib/rubygame/rect.rb, line 554 def normalize! if self.at(2) < 0 self[0], self[2] = self.at(0)+self.at(2), -self.at(2) end if self.at(3) < 0 self[1], self[3] = self.at(1)+self.at(3), -self.at(3) end self end
Set the x and y coordinates of the top-left corner of the Rect by translating the Rect (adjusting the x and y offsets).
# File lib/rubygame/rect.rb, line 252 def topleft=(topleft) raise ArgumentError, "Rect#topright= takes an Array of form [x, y]." if topleft.size != 2 self[0,2] = topleft return topleft end
Set the x and y coordinates of the top-right corner of the Rect by translating the Rect (adjusting the x and y offsets).
# File lib/rubygame/rect.rb, line 266 def topright=(topright) raise ArgumentError, "Rect#topright= takes an Array of form [x, y]." if topright.size != 2 self.right, self[1] = topright return topright end
Expand the caller to also cover the given Rect. The Rect is still a rectangle, so it may also cover areas that neither of the original Rects did, for example areas between the two Rects.
# File lib/rubygame/rect.rb, line 572 def union!(rect) self.normalize! rleft, rtop = self.topleft rright, rbottom = self.bottomright r2 = Rect.new_from_object(rect).normalize! rleft = [rleft, r2.left].min rtop = [rtop, r2.top].min rright = [rright, r2.right].max rbottom = [rbottom, r2.bottom].max self[0,4] = rleft, rtop, rright - rleft, rbottom - rtop return self end