class SFML::StencilMode

How a draw call interacts with the stencil buffer. The classic use is masking — first you draw a “mask” shape that writes a value into the stencil buffer, then you draw the masked content with a comparison that only lets pixels through where the stencil matches.

target.clear(SFML::Color.black, stencil: 0)

# Phase 1 — write the mask shape into the stencil buffer. write = SFML::StencilMode.new( comparison: :always, update_operation: :replace, reference: 1, only_write_mask: true, # don’t actually paint colour ) target.draw(mask_circle, stencil_mode: write)

# Phase 2 — draw the content; only pixels where stencil == 1 # survive. read = SFML::StencilMode.new( comparison: :equal, update_operation: :keep, reference: 1, ) target.draw(scene, stencil_mode: read)

stencilOnly (only_write_mask:) is a niche flag — set it to true on the mask-write pass if you don’t want the mask shape itself to be visible in the colour buffer.

Constants

COMPARISONS: Order matches sfStencilComparison in CSFML 3.
COMPARISON_INDEX: Comparison symbol → integer Hash.
OPERATIONS: Order matches sfStencilUpdateOperation in CSFML 3.
OPERATION_INDEX: Update-op symbol → integer Hash.

Attributes

The comparison, update operation, reference, mask, only write mask components.

The comparison, update operation, reference, mask, only write mask components.

only_write_mask [R]

The comparison, update operation, reference, mask, only write mask components.

The comparison, update operation, reference, mask, only write mask components.

update_operation [R]

The comparison, update operation, reference, mask, only write mask components.

Public Class Methods

from_native (struct)

Source

# File lib/sfml/graphics/stencil_mode.rb, line 88
def self.from_native(struct)
  new(
    comparison:       COMPARISONS[struct[:comparison]],
    update_operation: OPERATIONS[struct[:update_operation]],
    reference:        struct[:reference][:value],
    mask:             struct[:mask][:value],
    only_write_mask:  struct[:only_write_mask],
  )
end

@!visibility private

new (comparison: :always, update_operation: :keep, reference: 0, mask: 0xFFFFFFFF, only_write_mask: false)

Source

# File lib/sfml/graphics/stencil_mode.rb, line 41
def initialize(comparison: :always, update_operation: :keep,
               reference: 0, mask: 0xFFFFFFFF, only_write_mask: false)
  raise ArgumentError, "Unknown stencil comparison: #{comparison.inspect}" \
    unless COMPARISON_INDEX.key?(comparison)
  raise ArgumentError, "Unknown stencil update_operation: #{update_operation.inspect}" \
    unless OPERATION_INDEX.key?(update_operation)

  @comparison       = comparison
  @update_operation = update_operation
  @reference        = Integer(reference)
  @mask             = Integer(mask)
  @only_write_mask  = !!only_write_mask
  freeze
end

Public Instance Methods

Source

# File lib/sfml/graphics/stencil_mode.rb, line 56
def ==(other)
  other.is_a?(StencilMode) &&
    comparison == other.comparison &&
    update_operation == other.update_operation &&
    reference == other.reference &&
    mask == other.mask &&
    only_write_mask == other.only_write_mask
end

Also aliased as: eql?

Alias for: ==

hash (= [comparison, update_operation, reference, mask, only_write_mask].hash)

Source

# File lib/sfml/graphics/stencil_mode.rb, line 66
  def hash = [comparison, update_operation, reference, mask, only_write_mask].hash

  # Returns the to s.
  def to_s
    "StencilMode(#{comparison}, #{update_operation}, ref=#{reference}, " \
      "mask=#{format('0x%08X', mask)}, only_write=#{only_write_mask})"
  end
  alias inspect to_s

  # @!visibility private
  # Write our fields into a CSFML StencilMode struct (typically a
  # sub-struct of an existing RenderStates buffer).
  def populate(struct)
    struct[:comparison]       = COMPARISON_INDEX[@comparison]
    struct[:update_operation] = OPERATION_INDEX[@update_operation]
    struct[:reference][:value] = @reference
    struct[:mask][:value]      = @mask
    struct[:only_write_mask]  = @only_write_mask
    struct
  end

  # @!visibility private
  def self.from_native(struct)
    new(
      comparison:       COMPARISONS[struct[:comparison]],
      update_operation: OPERATIONS[struct[:update_operation]],
      reference:        struct[:reference][:value],
      mask:             struct[:mask][:value],
      only_write_mask:  struct[:only_write_mask],
    )
  end
end

Returns the hash.

populate (struct)

Source

# File lib/sfml/graphics/stencil_mode.rb, line 78
def populate(struct)
  struct[:comparison]       = COMPARISON_INDEX[@comparison]
  struct[:update_operation] = OPERATION_INDEX[@update_operation]
  struct[:reference][:value] = @reference
  struct[:mask][:value]      = @mask
  struct[:only_write_mask]  = @only_write_mask
  struct
end

@!visibility private Write our fields into a CSFML StencilMode struct (typically a sub-struct of an existing RenderStates buffer).

Source

# File lib/sfml/graphics/stencil_mode.rb, line 69
def to_s
  "StencilMode(#{comparison}, #{update_operation}, ref=#{reference}, " \
    "mask=#{format('0x%08X', mask)}, only_write=#{only_write_mask})"
end

Returns the to s.