module ChunkyPNG::Canvas::Resampling

def resample_nearest_neighbor(new_width, new_height) 

def resample_nearest_neighbor(new_width, new_height)
  dup.resample_nearest_neighbor!(new_width, new_height)
end

def resample_nearest_neighbor!(new_width, new_height)

Returns:
  • (ChunkyPNG::Canvas) - A new canvas instance with the resampled pixels.

Parameters:
  • new_height (Integer) -- The height of the resampled canvas.
  • new_width (Integer) -- The width of the resampled canvas. 
def resample_nearest_neighbor!(new_width, new_height)
  
  width_ratio  = width.to_f / new_width.to_f
  height_ratio = height.to_f / new_height.to_f
  pixels = []
  for y in 1..new_height do
    source_y   = (y - 0.5) * height_ratio + 0.5
    input_y    = source_y.to_i
    for x in 1..new_width do
      source_x = (x - 0.5) * width_ratio + 0.5
      input_x  = source_x.to_i
      pixels << get_pixel([input_x - 1, 0].max, [input_y - 1, 0].max)
    end
  end
  
  replace_canvas!(new_width.to_i, new_height.to_i, pixels)
end