Class: Contrek::Bitmaps::SampleGenerator

Inherits:
Object
  • Object
show all
Defined in:
lib/contrek/bitmaps/sample_generator.rb

Constant Summary collapse

DIR4 = 
[[1, 0], [-1, 0], [0, 1], [0, -1]]
DIR8 = 
[[1, 0], [-1, 0], [0, 1], [0, -1], [1, 1], [1, -1], [-1, 1], [-1, -1]]

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(rows:, cols:, seed: nil, fill: 0) ⇒ SampleGenerator

Returns a new instance of SampleGenerator.



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# File 'lib/contrek/bitmaps/sample_generator.rb', line 7

def initialize(rows:, cols:, seed: nil, fill: 0)
  @rows = rows
  @cols = cols
  @grid = Array.new(rows) { Array.new(cols, fill) }
  srand(seed) if seed
end

Instance Attribute Details

#cols ⇒ Object (readonly)

Returns the value of attribute cols.



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# File 'lib/contrek/bitmaps/sample_generator.rb', line 6

def cols
  @cols
end

#grid ⇒ Object (readonly)

Returns the value of attribute grid.



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# File 'lib/contrek/bitmaps/sample_generator.rb', line 6

def grid
  @grid
end

#rows ⇒ Object (readonly)

Returns the value of attribute rows.



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# File 'lib/contrek/bitmaps/sample_generator.rb', line 6

def rows
  @rows
end

Instance Method Details

#generate_blob_islands(count: 4, min_radius: 2, max_radius: 5, noise: 0.85) ⇒ Object 



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# File 'lib/contrek/bitmaps/sample_generator.rb', line 29

def generate_blob_islands(count: 4, min_radius: 2, max_radius: 5, noise: 0.85)
  count.times do
    cx = rand(@rows)
    cy = rand(@cols)
    r = rand(min_radius..max_radius)
    (cx - r).upto(cx + r) do |x|
      (cy - r).upto(cy + r) do |y|
        next unless in_bounds?(x, y)
        dx = x - cx
        dy = y - cy
        @grid[x][y] = 1 if (dx * dx + dy * dy) <= r * r && rand < noise
      end
    end
  end
end

#generate_islands(count: 6, max_steps: 40, grow_probability: 0.9) ⇒ Object 



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# File 'lib/contrek/bitmaps/sample_generator.rb', line 14

def generate_islands(count: 6, max_steps: 40, grow_probability: 0.9)
  count.times do
    x = rand(@rows)
    y = rand(@cols)
    rand(max_steps / 2..max_steps).times do
      @grid[x][y] = 1 if rand < grow_probability
      dx, dy = DIR8.sample
      nx = x + dx
      ny = y + dy
      break unless in_bounds?(nx, ny)
      x, y = nx, ny
    end
  end
end

#to_chunk ⇒ Object 



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# File 'lib/contrek/bitmaps/sample_generator.rb', line 45

def to_chunk
  @grid.join
end