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using System; |
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|
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namespace Oni |
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{ |
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internal static class MathHelper |
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{ |
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public const float Eps = 1e-5f; |
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public const float Pi = 3.141593f; |
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public const float HalfPi = Pi / 2.0f; |
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public const float PiOver4 = Pi / 4.0f; |
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public const float TwoPi = 2.0f * Pi; |
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|
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public static float ToDegrees(float radians) => radians * (180.0f / Pi); |
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public static float ToRadians(float degrees) => degrees * (Pi / 180.0f); |
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public static float Distance(float v1, float v2) => Math.Abs(v2 - v1); |
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public static float Lerp(float v1, float v2, float amount) => v1 + (v2 - v1) * amount; |
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|
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public static int Lerp(int v1, int v2, float amount) |
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{ |
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if (amount == 0.0f) |
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return v1; |
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|
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if (amount == 1.0f) |
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return v2; |
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|
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return (int)(v1 + (v2 - v1) * amount); |
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} |
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|
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public static float Clamp(float v, float min, float max) |
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{ |
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v = (v > max) ? max : v; |
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v = (v < min) ? min : v; |
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|
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return v; |
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} |
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|
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public static int Clamp(int v, int min, int max) |
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{ |
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v = (v > max) ? max : v; |
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v = (v < min) ? min : v; |
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|
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return v; |
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} |
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|
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public static float Area(Vector2[] points) |
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{ |
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float area = 0.0f; |
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|
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for (int i = 0; i < points.Length; i++) |
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{ |
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int j = (i + 1) % points.Length; |
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area += points[i].X * points[j].Y; |
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area -= points[i].Y * points[j].X; |
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} |
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|
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return Math.Abs(area * 0.5f); |
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} |
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} |
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} |