Class: Badline::VIC::Sprites

Inherits:
Object
  • Object
show all
Defined in:
lib/badline/vic/sprites.rb

Constant Summary collapse

SPRITE_COLLISION_IRQ =

$D019 latch bits raised by the collision registers.

0x04
DATA_COLLISION_IRQ =

IMMC, mirrors $D01E

0x02

Instance Method Summary collapse

Constructor Details

#initialize(registers, bank, width) ⇒ Sprites

IMBC, mirrors $D01F



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# File 'lib/badline/vic/sprites.rb', line 12

def initialize(registers, bank, width)
  @registers = registers
  @bank = bank
  @width = width
  @sprites = Array.new(8) { |i| Sprite.new(i, registers, bank, width) }
  @hits = Array.new(width, 0)
  @win_color = Array.new(width, 0)
  @win_priority = Array.new(width, false)
end

Instance Method Details

#[](index) ⇒ Object 



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# File 'lib/badline/vic/sprites.rb', line 22

def [](index) = @sprites[index]

#active? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/badline/vic/sprites.rb', line 28

def active? = @sprites.any?(&:displaying?)

#composite(colors, mask) ⇒ Object

Merge each displaying sprite’s line into the scratch buffers, then apply the winners over the background in a single pass over the touched span.



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# File 'lib/badline/vic/sprites.rb', line 33

def composite(colors, mask)
  @sprite_clash = 0
  @data_clash = 0
  lo = @width
  hi = 0

  @sprites.each do |sprite|
    next unless sprite.displaying?

    seg_lo, seg_hi = merge(sprite, mask)
    lo = seg_lo if seg_lo < lo
    hi = seg_hi if seg_hi > hi
  end

  apply(colors, mask, lo, hi)
  register_collisions
end

#start_line(line) ⇒ Object 



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# File 'lib/badline/vic/sprites.rb', line 24

def start_line(line)
  @sprites.each { |sprite| sprite.start_line(line) }
end