31 lines
797 B
Nim
31 lines
797 B
Nim
import math
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type Point = tuple[x,y,z: float]
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const shades = ".:!*oe&#%@"
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proc normalize(x, y, z: float): Point =
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let len = sqrt(x*x + y*y + z*z)
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(x / len, y / len, z / len)
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proc dot(a, b: Point): float =
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result = max(0, - a.x*b.x - a.y*b.y - a.z*b.z)
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let light = normalize(30.0, 30.0, -50.0)
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proc drawSphere(r, k, ambient) =
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for i in -r .. r:
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let x = i.float + 0.5
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for j in -2*r .. 2*r:
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let y = j.float / 2.0 + 0.5
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if x*x + y*y <= float r*r:
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let
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v = normalize(x, y, sqrt(float(r*r) - x*x - y*y))
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b = pow(dot(light, v), k) + ambient
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i = clamp(int((1.0 - b) * shades.high.float), 0, shades.high)
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stdout.write shades[i]
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else: stdout.write ' '
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stdout.write "\n"
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drawSphere 20, 4.0, 0.1
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drawSphere 10, 2.0, 0.4
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