40 lines
995 B
Ruby
40 lines
995 B
Ruby
Pixel = Struct.new(:x, :y)
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class Pixmap
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def draw_circle(pixel, radius, colour)
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validate_pixel(pixel.x, pixel.y)
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self[pixel.x, pixel.y + radius] = colour
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self[pixel.x, pixel.y - radius] = colour
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self[pixel.x + radius, pixel.y] = colour
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self[pixel.x - radius, pixel.y] = colour
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f = 1 - radius
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ddF_x = 1
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ddF_y = -2 * radius
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x = 0
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y = radius
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while x < y
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if f >= 0
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y -= 1
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ddF_y += 2
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f += ddF_y
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end
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x += 1
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ddF_x += 2
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f += ddF_x
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self[pixel.x + x, pixel.y + y] = colour
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self[pixel.x + x, pixel.y - y] = colour
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self[pixel.x - x, pixel.y + y] = colour
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self[pixel.x - x, pixel.y - y] = colour
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self[pixel.x + y, pixel.y + x] = colour
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self[pixel.x + y, pixel.y - x] = colour
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self[pixel.x - y, pixel.y + x] = colour
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self[pixel.x - y, pixel.y - x] = colour
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end
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end
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end
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bitmap = Pixmap.new(30, 30)
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bitmap.draw_circle(Pixel[14,14], 12, RGBColour::BLACK)
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