Class: SFML::View

Inherits:
Object
  • Object
show all
Defined in:
lib/sfml/graphics/view.rb

Overview

A 2D camera. A View defines what part of the world is visible in the window: a centre point, a size in world units, an optional rotation, and a viewport rectangle (in normalised window coords [0,1]) that places the view inside the window — useful for split-screen or for rendering a mini-map alongside the main camera.

Two flows you'll typically use:

# 1. Define from a centre + size:
camera = SFML::View.new(center: [400, 300], size: [800, 600])

# 2. Define from a world rectangle (top-left + size):
camera = SFML::View.from_rect(SFML::Rect.new([0, 0], [1600, 1200]))

window.view = camera         # apply
window.draw(stuff)           # everything draws through the camera
window.view = window.default_view   # restore the 1:1 default

All coordinate inputs accept either a SFML::Vector2 or a [x, y] array.

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(center: nil, size: nil, rotation: nil, viewport: nil, _handle: nil) ⇒ View

Build a View. All four kwargs may be passed up-front or set later. _handle: is for internal wrapping of CSFML pointers.

Raises:



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# File 'lib/sfml/graphics/view.rb', line 24

def initialize(center: nil, size: nil, rotation: nil, viewport: nil, _handle: nil)
  ptr = _handle || C::Graphics.sfView_create
  raise GraphicsError, "sfView_create returned NULL" if ptr.null?
  @handle = FFI::AutoPointer.new(ptr, C::Graphics.method(:sfView_destroy))

  self.center   = center   if center
  self.size     = size     if size
  self.rotation = rotation if rotation
  self.viewport = viewport if viewport
end

Instance Attribute Details

#handle ⇒ Object (readonly)

:nodoc:



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# File 'lib/sfml/graphics/view.rb', line 136

def handle
  @handle
end

Class Method Details

.from_rect(rect) ⇒ Object

Build a View whose rectangle covers the given world Rect.

Raises:

  • (ArgumentError) 


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# File 'lib/sfml/graphics/view.rb', line 36

def self.from_rect(rect)
  raise ArgumentError, "View.from_rect needs a SFML::Rect" unless rect.is_a?(Rect)

  native = C::Graphics::FloatRect.new
  native[:position][:x] = rect.x.to_f
  native[:position][:y] = rect.y.to_f
  native[:size][:x]     = rect.width.to_f
  native[:size][:y]     = rect.height.to_f

  ptr = C::Graphics.sfView_createFromRect(native)
  raise GraphicsError, "sfView_createFromRect returned NULL" if ptr.null?
  new(_handle: ptr)
end

Instance Method Details

#center ⇒ Object

Centre point of the view in world coordinates.



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# File 'lib/sfml/graphics/view.rb', line 61

def center
  Vector2.from_native(C::Graphics.sfView_getCenter(@handle))
end

#center=(value) ⇒ Object

Set the center.



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# File 'lib/sfml/graphics/view.rb', line 66

def center=(value)
  C::Graphics.sfView_setCenter(@handle, _vec2(value).to_native_f)
end

#move(offset) ⇒ Object

Pan the camera by an offset in world units.



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# File 'lib/sfml/graphics/view.rb', line 118

def move(offset)
  C::Graphics.sfView_move(@handle, _vec2(offset).to_native_f)
  self
end

#rotate(degrees) ⇒ Object

Rotate the camera by degrees, relative to current rotation.



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# File 'lib/sfml/graphics/view.rb', line 124

def rotate(degrees)
  C::Graphics.sfView_rotate(@handle, degrees.to_f)
  self
end

#rotation ⇒ Object

Rotation in degrees (counter-clockwise).



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# File 'lib/sfml/graphics/view.rb', line 81

def rotation
  C::Graphics.sfView_getRotation(@handle)
end

#rotation=(degrees) ⇒ Object

Set the rotation.



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# File 'lib/sfml/graphics/view.rb', line 86

def rotation=(degrees)
  C::Graphics.sfView_setRotation(@handle, degrees.to_f)
end

#scissor ⇒ Object

Scissor rect in normalised [0,1] window coords — pixels outside this rect are clipped before rendering. Default [0, 0, 1, 1] (no clipping). Use it to render UI inside a sub-region of the window without re-projecting.



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# File 'lib/sfml/graphics/view.rb', line 107

def scissor
  Rect.from_native(C::Graphics.sfView_getScissor(@handle))
end

#scissor=(rect) ⇒ Object

Set the scissor.

Raises:

  • (ArgumentError) 


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# File 'lib/sfml/graphics/view.rb', line 112

def scissor=(rect)
  raise ArgumentError, "View#scissor= needs a SFML::Rect" unless rect.is_a?(Rect)
  C::Graphics.sfView_setScissor(@handle, _to_floatrect(rect))
end

#size ⇒ Object

Visible area in world units (NOT pixels). Halving this zooms in.



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# File 'lib/sfml/graphics/view.rb', line 71

def size
  Vector2.from_native(C::Graphics.sfView_getSize(@handle))
end

#size=(value) ⇒ Object

Set the size.



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# File 'lib/sfml/graphics/view.rb', line 76

def size=(value)
  C::Graphics.sfView_setSize(@handle, _vec2(value).to_native_f)
end

#viewport ⇒ Object

Viewport in normalised [0,1] window coordinates. Default is the full window (Rect.new([0,0], [1,1])). Use [0, 0, 0.5, 1] for left half, [0.75, 0, 0.25, 0.25] for a top-right mini-map, etc.



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# File 'lib/sfml/graphics/view.rb', line 93

def viewport
  Rect.from_native(C::Graphics.sfView_getViewport(@handle))
end

#viewport=(rect) ⇒ Object

Set the viewport.

Raises:

  • (ArgumentError) 


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# File 'lib/sfml/graphics/view.rb', line 98

def viewport=(rect)
  raise ArgumentError, "View#viewport= needs a SFML::Rect" unless rect.is_a?(Rect)
  C::Graphics.sfView_setViewport(@handle, _to_floatrect(rect))
end

#zoom(factor) ⇒ Object

Multiply the visible area by factor. Factor < 1.0 zooms in; factor > 1.0 zooms out.



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# File 'lib/sfml/graphics/view.rb', line 131

def zoom(factor)
  C::Graphics.sfView_zoom(@handle, factor.to_f)
  self
end