Work in a 320x180 resolution in DragonRuby

main.rb

# https://dragonruby.itch.io/

BUFFER_W = 1280.div(4)  # 320
BUFFER_H = 720.div(4)   # 180

def tick args
  args.render_target(:buffer).sprites << {
    x: 0,
    y: 0,
    w: BUFFER_W,
    h: BUFFER_H,
    path: 'sprites/Sprite-320x180.png'
  }

  args.outputs.sprites << {
    x: 0,
    y: 0,
    w: 1280,
    h: 720,
    path: :buffer,
    source_x: 0,
    source_y: 0,
    source_w: BUFFER_W,
    source_h: BUFFER_H
  }
end