36 lines
689 B
Nim
36 lines
689 B
Nim
import bitmap
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proc drawLine*(img: Image; p, q: Point; color: Color) =
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let
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dx = abs(q.x - p.x)
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sx = if p.x < q.x: 1 else: -1
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dy = abs(q.y - p.y)
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sy = if p.y < q.y: 1 else: -1
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var
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p = p
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q = q
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err = (if dx > dy: dx else: -dy) div 2
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e2 = 0
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while true:
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img[p.x, p.y] = color
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if p == q:
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break
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e2 = err
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if e2 > -dx:
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err -= dy
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p.x += sx
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if e2 < dy:
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err += dx
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p.y += sy
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when isMainModule:
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var img = newImage(16, 16)
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img.fill(White)
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img.drawLine((0, 7), (7, 15), Black)
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img.drawLine((7, 15), (15, 7), Black)
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img.drawLine((15, 7), (7, 0), Black)
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img.drawLine((7, 0), (0, 7), Black)
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img.print()
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