Class: Prawn::Document::BoundingBox

Inherits:
Object
  • Object
show all
Defined in:
lib/prawn/document/bounding_box.rb

Overview

Low level layout helper that simplifies coordinate math.

See #bounding_box for a description of what this class is used for.

Direct Known Subclasses

ColumnBox

Defined Under Namespace

Classes: NoReferenceBounds

Stable API collapse

Stable API collapse

Extension API collapse

Instance Attribute Details

#width ⇒ Number (readonly)

Width of the bounding box.

Returns:

  • (Number)
Source Code
lib/prawn/document/bounding_box.rb, line 522
522
def width

523
  @width

524
end

Instance Method Details

#absolute_bottom ⇒ Number

Absolute bottom y-coordinate of the bottom box.

Returns:

  • (Number)
Source Code
lib/prawn/document/bounding_box.rb, line 487
487
def absolute_bottom

488
  @y - height

489
end

#absolute_bottom_left ⇒ Array(Number, Number)

Absolute bottom-left point of the bounding box.

Returns:

  • (Array(Number, Number))
Source Code
lib/prawn/document/bounding_box.rb, line 508
508
def absolute_bottom_left

509
  [absolute_left, absolute_bottom]

510
end

#absolute_bottom_right ⇒ Array(Number, Number)

Absolute bottom-left point of the bounding box.

Returns:

  • (Array(Number, Number))
Source Code
lib/prawn/document/bounding_box.rb, line 515
515
def absolute_bottom_right

516
  [absolute_right, absolute_bottom]

517
end

#absolute_left ⇒ Number

Absolute left x-coordinate of the bounding box.

Returns:

  • (Number)
Source Code
lib/prawn/document/bounding_box.rb, line 466
466
def absolute_left

467
  @x

468
end

#absolute_right ⇒ Number

Absolute right x-coordinate of the bounding box.

Returns:

  • (Number)
Source Code
lib/prawn/document/bounding_box.rb, line 473
473
def absolute_right

474
  @x + width

475
end

#absolute_top ⇒ Number

Absolute top y-coordinate of the bounding box.

Returns:

  • (Number)
Source Code
lib/prawn/document/bounding_box.rb, line 480
480
def absolute_top

481
  @y

482
end

#absolute_top_left ⇒ Array(Number, Number)

Absolute top-left point of the bounding box.

Returns:

  • (Array(Number, Number))
Source Code
lib/prawn/document/bounding_box.rb, line 494
494
def absolute_top_left

495
  [absolute_left, absolute_top]

496
end

#absolute_top_right ⇒ Array(Number, Number)

Absolute top-right point of the bounding box.

Returns:

  • (Array(Number, Number))
Source Code
lib/prawn/document/bounding_box.rb, line 501
501
def absolute_top_right

502
  [absolute_right, absolute_top]

503
end

#bottom ⇒ Number

Relative bottom y-coordinate of the bounding box. Always 0.

Examples:

Position some text 3 pts from the bottom of the containing box

draw_text('hello', at: [0, (bounds.bottom + 3)])

Returns:

  • (Number)
Source Code
lib/prawn/document/bounding_box.rb, line 411
411
def bottom

412
  0

413
end

#bottom_left ⇒ Array(Number, Number)

Relative bottom-left point of the bounding box.

Examples:

Draw a line along the left hand side of the page

stroke do
  line(bounds.bottom_left, bounds.top_left)
end

Returns:

  • (Array(Number, Number))
Source Code
lib/prawn/document/bounding_box.rb, line 459
459
def bottom_left

460
  [left, bottom]

461
end

#bottom_right ⇒ Array(Number, Number)

Relative bottom-right point of the bounding box.

Examples:

Draw a line along the right hand side of the page

stroke do
  line(bounds.bottom_right, bounds.top_right)
end

Returns:

  • (Array(Number, Number))
Source Code
lib/prawn/document/bounding_box.rb, line 447
447
def bottom_right

448
  [right, bottom]

449
end

#height ⇒ Number Also known as: update_height

Height of the bounding box. If the box is ‘stretchy’ (unspecified height attribute), height is calculated as the distance from the top of the box to the current drawing position.

Returns:

  • (Number)
Source Code
lib/prawn/document/bounding_box.rb, line 529
529
def height

530
  return @height if @height

531
532
  @stretched_height = [

533
    (absolute_top - @document.y),

534
    Float(@stretched_height || 0.0),

535
  ].max

536
end







    
      

  

  
    #left  ⇒ Number 
  

  

  


  

    
Relative left x-coordinate of the bounding box. Always 0.



  





  
  

    
Examples:

    
      
        
Position some text 3 pts from the left of the containing box



      
      
draw_text('hello', at: [(bounds.left + 3), 0])


    
  




Returns:


    
  
    
  • 
      
      
        (Number)
      
      
      
    
    • 
  







  Source Code
  
lib/prawn/document/bounding_box.rb, line 312

  
312
def left

313
  0

314
end







    
      

  

  
    #move_past_bottom  ⇒ void 
  

  

  


  

    
This method returns an undefined value.
Moves to the top of the next page of the document, starting a new page
if necessary.



  





  






  Source Code
  
lib/prawn/document/bounding_box.rb, line 560

  
560
def move_past_bottom

561
  if @document.page_number == @document.page_count

562
    @document.start_new_page

563
  else

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    @document.go_to_page(@document.page_number + 1)

565
  end

566
end







    
      

  

  
    #reference_bounds  ⇒ BoundingBox 
  

  

  


  

    
Returns the innermost non-stretchy bounding box.



  





  


Returns:



Raises:







  Source Code
  
lib/prawn/document/bounding_box.rb, line 581

  
581
def reference_bounds

582
  if stretchy?

583
    raise NoReferenceBounds unless @parent

584
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    @parent.reference_bounds

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  else

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    self

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  end

589
end







    
      

  

  
    #right  ⇒ Number 
  

  

  


  

    
Relative right x-coordinate of the bounding box. Equal to the box width.



  





  
  

    
Examples:

    
      
        
Position some text 3 pts from the right of the containing box



      
      
draw_text('hello', at: [(bounds.right - 3), 0])


    
  




Returns:


    
  
    
  • 
      
      
        (Number)
      
      
      
    
    • 
  







  Source Code
  
lib/prawn/document/bounding_box.rb, line 391

  
391
def right

392
  @width

393
end







    
      

  

  
    #stretchy?  ⇒ Boolean 
  

  

  


  

    
Returns false when the box has a defined height, true when the
height is being calculated on the fly based on the current vertical
position.



  





  


Returns:


    
  
    
  • 
      
      
        (Boolean)
      
      
      
    
    • 
  







  Source Code
  
lib/prawn/document/bounding_box.rb, line 573

  
573
def stretchy?

574
  !@height

575
end







    
      

  

  
    #top  ⇒ Number 
  

  

  


  

    
Relative top y-coordinate of the bounding box. Equal to the box height.



  





  
  

    
Examples:

    
      
        
Position some text 3 pts from the top of the containing box



      
      
draw_text('hello', at: [0, (bounds.top - 3)])


    
  




Returns:


    
  
    
  • 
      
      
        (Number)
      
      
      
    
    • 
  







  Source Code
  
lib/prawn/document/bounding_box.rb, line 401

  
401
def top

402
  height

403
end







    
      

  

  
    #top_left  ⇒ Array(Number, Number) 
  

  

  


  

    
Relative top-left point of the bounding_box.



  





  
  

    
Examples:

    
      
        
Draw a line from the top left of the box diagonally to the bottom right



      
      
stroke do
  line(bounds.top_left, bounds.bottom_right)
end


    
  




Returns:


    
  
    
  • 
      
      
        (Array(Number, Number))
      
      
      
    
    • 
  







  Source Code
  
lib/prawn/document/bounding_box.rb, line 423

  
423
def top_left

424
  [left, top]

425
end







    
      

  

  
    #top_right  ⇒ Array(Number, Number) 
  

  

  


  

    
Relative top-right point of the bounding box.



  





  
  

    
Examples:

    
      
        
Draw a line from the top_right of the box diagonally to the bottom left



      
      
stroke do
  line(bounds.top_right, bounds.bottom_left)
end


    
  




Returns:


    
  
    
  • 
      
      
        (Array(Number, Number))
      
      
      
    
    • 
  







  Source Code
  
lib/prawn/document/bounding_box.rb, line 435

  
435
def top_right

436
  [right, top]

437
end