551 lines
18 KiB
C++
551 lines
18 KiB
C++
//
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// Copyright (c) 2009-2010 Mikko Mononen memon@inside.org
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//
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// This software is provided 'as-is', without any express or implied
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// warranty. In no event will the authors be held liable for any damages
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// arising from the use of this software.
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// Permission is granted to anyone to use this software for any purpose,
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// including commercial applications, and to alter it and redistribute it
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// freely, subject to the following restrictions:
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// 1. The origin of this software must not be misrepresented; you must not
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// claim that you wrote the original software. If you use this software
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// in a product, an acknowledgment in the product documentation would be
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// appreciated but is not required.
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// 2. Altered source versions must be plainly marked as such, and must not be
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// misrepresented as being the original software.
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// 3. This notice may not be removed or altered from any source distribution.
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//
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#ifndef DETOURCOMMON_H
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#define DETOURCOMMON_H
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#include "DetourMath.h"
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#include <stddef.h>
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/**
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@defgroup detour Detour
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Members in this module are used to create, manipulate, and query navigation
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meshes.
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@note This is a summary list of members. Use the index or search
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feature to find minor members.
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*/
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/// @name General helper functions
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/// @{
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/// Used to ignore a function parameter. VS complains about unused parameters
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/// and this silences the warning.
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/// @param [in] _ Unused parameter
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template<class T> void dtIgnoreUnused(const T&) { }
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/// Swaps the values of the two parameters.
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/// @param[in,out] a Value A
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/// @param[in,out] b Value B
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template<class T> inline void dtSwap(T& a, T& b) { T t = a; a = b; b = t; }
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/// Returns the minimum of two values.
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/// @param[in] a Value A
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/// @param[in] b Value B
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/// @return The minimum of the two values.
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template<class T> inline T dtMin(T a, T b) { return a < b ? a : b; }
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/// Returns the maximum of two values.
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/// @param[in] a Value A
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/// @param[in] b Value B
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/// @return The maximum of the two values.
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template<class T> inline T dtMax(T a, T b) { return a > b ? a : b; }
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/// Returns the absolute value.
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/// @param[in] a The value.
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/// @return The absolute value of the specified value.
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template<class T> inline T dtAbs(T a) { return a < 0 ? -a : a; }
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/// Returns the square of the value.
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/// @param[in] a The value.
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/// @return The square of the value.
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template<class T> inline T dtSqr(T a) { return a*a; }
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/// Clamps the value to the specified range.
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/// @param[in] v The value to clamp.
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/// @param[in] mn The minimum permitted return value.
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/// @param[in] mx The maximum permitted return value.
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/// @return The value, clamped to the specified range.
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template<class T> inline T dtClamp(T v, T mn, T mx) { return v < mn ? mn : (v > mx ? mx : v); }
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/// @}
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/// @name Vector helper functions.
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/// @{
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/// Derives the cross product of two vectors. (@p v1 x @p v2)
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/// @param[out] dest The cross product. [(x, y, z)]
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/// @param[in] v1 A Vector [(x, y, z)]
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/// @param[in] v2 A vector [(x, y, z)]
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inline void dtVcross(float* dest, const float* v1, const float* v2)
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{
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dest[0] = v1[1]*v2[2] - v1[2]*v2[1];
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dest[1] = v1[2]*v2[0] - v1[0]*v2[2];
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dest[2] = v1[0]*v2[1] - v1[1]*v2[0];
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}
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/// Derives the dot product of two vectors. (@p v1 . @p v2)
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/// @param[in] v1 A Vector [(x, y, z)]
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/// @param[in] v2 A vector [(x, y, z)]
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/// @return The dot product.
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inline float dtVdot(const float* v1, const float* v2)
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{
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return v1[0]*v2[0] + v1[1]*v2[1] + v1[2]*v2[2];
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}
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/// Performs a scaled vector addition. (@p v1 + (@p v2 * @p s))
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/// @param[out] dest The result vector. [(x, y, z)]
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/// @param[in] v1 The base vector. [(x, y, z)]
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/// @param[in] v2 The vector to scale and add to @p v1. [(x, y, z)]
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/// @param[in] s The amount to scale @p v2 by before adding to @p v1.
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inline void dtVmad(float* dest, const float* v1, const float* v2, const float s)
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{
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dest[0] = v1[0]+v2[0]*s;
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dest[1] = v1[1]+v2[1]*s;
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dest[2] = v1[2]+v2[2]*s;
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}
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/// Performs a linear interpolation between two vectors. (@p v1 toward @p v2)
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/// @param[out] dest The result vector. [(x, y, x)]
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/// @param[in] v1 The starting vector.
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/// @param[in] v2 The destination vector.
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/// @param[in] t The interpolation factor. [Limits: 0 <= value <= 1.0]
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inline void dtVlerp(float* dest, const float* v1, const float* v2, const float t)
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{
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dest[0] = v1[0]+(v2[0]-v1[0])*t;
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dest[1] = v1[1]+(v2[1]-v1[1])*t;
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dest[2] = v1[2]+(v2[2]-v1[2])*t;
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}
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/// Performs a vector addition. (@p v1 + @p v2)
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/// @param[out] dest The result vector. [(x, y, z)]
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/// @param[in] v1 The base vector. [(x, y, z)]
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/// @param[in] v2 The vector to add to @p v1. [(x, y, z)]
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inline void dtVadd(float* dest, const float* v1, const float* v2)
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{
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dest[0] = v1[0]+v2[0];
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dest[1] = v1[1]+v2[1];
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dest[2] = v1[2]+v2[2];
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}
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/// Performs a vector subtraction. (@p v1 - @p v2)
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/// @param[out] dest The result vector. [(x, y, z)]
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/// @param[in] v1 The base vector. [(x, y, z)]
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/// @param[in] v2 The vector to subtract from @p v1. [(x, y, z)]
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inline void dtVsub(float* dest, const float* v1, const float* v2)
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{
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dest[0] = v1[0]-v2[0];
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dest[1] = v1[1]-v2[1];
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dest[2] = v1[2]-v2[2];
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}
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/// Scales the vector by the specified value. (@p v * @p t)
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/// @param[out] dest The result vector. [(x, y, z)]
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/// @param[in] v The vector to scale. [(x, y, z)]
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/// @param[in] t The scaling factor.
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inline void dtVscale(float* dest, const float* v, const float t)
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{
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dest[0] = v[0]*t;
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dest[1] = v[1]*t;
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dest[2] = v[2]*t;
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}
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/// Selects the minimum value of each element from the specified vectors.
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/// @param[in,out] mn A vector. (Will be updated with the result.) [(x, y, z)]
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/// @param[in] v A vector. [(x, y, z)]
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inline void dtVmin(float* mn, const float* v)
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{
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mn[0] = dtMin(mn[0], v[0]);
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mn[1] = dtMin(mn[1], v[1]);
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mn[2] = dtMin(mn[2], v[2]);
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}
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/// Selects the maximum value of each element from the specified vectors.
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/// @param[in,out] mx A vector. (Will be updated with the result.) [(x, y, z)]
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/// @param[in] v A vector. [(x, y, z)]
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inline void dtVmax(float* mx, const float* v)
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{
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mx[0] = dtMax(mx[0], v[0]);
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mx[1] = dtMax(mx[1], v[1]);
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mx[2] = dtMax(mx[2], v[2]);
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}
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/// Sets the vector elements to the specified values.
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/// @param[out] dest The result vector. [(x, y, z)]
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/// @param[in] x The x-value of the vector.
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/// @param[in] y The y-value of the vector.
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/// @param[in] z The z-value of the vector.
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inline void dtVset(float* dest, const float x, const float y, const float z)
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{
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dest[0] = x; dest[1] = y; dest[2] = z;
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}
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/// Performs a vector copy.
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/// @param[out] dest The result. [(x, y, z)]
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/// @param[in] a The vector to copy. [(x, y, z)]
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inline void dtVcopy(float* dest, const float* a)
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{
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dest[0] = a[0];
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dest[1] = a[1];
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dest[2] = a[2];
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}
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/// Derives the scalar length of the vector.
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/// @param[in] v The vector. [(x, y, z)]
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/// @return The scalar length of the vector.
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inline float dtVlen(const float* v)
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{
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return dtMathSqrtf(v[0] * v[0] + v[1] * v[1] + v[2] * v[2]);
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}
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/// Derives the square of the scalar length of the vector. (len * len)
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/// @param[in] v The vector. [(x, y, z)]
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/// @return The square of the scalar length of the vector.
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inline float dtVlenSqr(const float* v)
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{
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return v[0]*v[0] + v[1]*v[1] + v[2]*v[2];
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}
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/// Returns the distance between two points.
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/// @param[in] v1 A point. [(x, y, z)]
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/// @param[in] v2 A point. [(x, y, z)]
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/// @return The distance between the two points.
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inline float dtVdist(const float* v1, const float* v2)
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{
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const float dx = v2[0] - v1[0];
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const float dy = v2[1] - v1[1];
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const float dz = v2[2] - v1[2];
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return dtMathSqrtf(dx*dx + dy*dy + dz*dz);
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}
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/// Returns the square of the distance between two points.
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/// @param[in] v1 A point. [(x, y, z)]
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/// @param[in] v2 A point. [(x, y, z)]
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/// @return The square of the distance between the two points.
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inline float dtVdistSqr(const float* v1, const float* v2)
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{
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const float dx = v2[0] - v1[0];
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const float dy = v2[1] - v1[1];
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const float dz = v2[2] - v1[2];
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return dx*dx + dy*dy + dz*dz;
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}
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/// Derives the distance between the specified points on the xz-plane.
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/// @param[in] v1 A point. [(x, y, z)]
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/// @param[in] v2 A point. [(x, y, z)]
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/// @return The distance between the point on the xz-plane.
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///
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/// The vectors are projected onto the xz-plane, so the y-values are ignored.
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inline float dtVdist2D(const float* v1, const float* v2)
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{
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const float dx = v2[0] - v1[0];
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const float dz = v2[2] - v1[2];
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return dtMathSqrtf(dx*dx + dz*dz);
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}
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/// Derives the square of the distance between the specified points on the xz-plane.
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/// @param[in] v1 A point. [(x, y, z)]
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/// @param[in] v2 A point. [(x, y, z)]
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/// @return The square of the distance between the point on the xz-plane.
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inline float dtVdist2DSqr(const float* v1, const float* v2)
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{
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const float dx = v2[0] - v1[0];
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const float dz = v2[2] - v1[2];
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return dx*dx + dz*dz;
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}
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/// Normalizes the vector.
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/// @param[in,out] v The vector to normalize. [(x, y, z)]
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inline void dtVnormalize(float* v)
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{
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float d = 1.0f / dtMathSqrtf(dtSqr(v[0]) + dtSqr(v[1]) + dtSqr(v[2]));
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v[0] *= d;
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v[1] *= d;
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v[2] *= d;
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}
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/// Performs a 'sloppy' colocation check of the specified points.
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/// @param[in] p0 A point. [(x, y, z)]
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/// @param[in] p1 A point. [(x, y, z)]
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/// @return True if the points are considered to be at the same location.
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///
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/// Basically, this function will return true if the specified points are
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/// close enough to eachother to be considered colocated.
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inline bool dtVequal(const float* p0, const float* p1)
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{
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static const float thr = dtSqr(1.0f/16384.0f);
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const float d = dtVdistSqr(p0, p1);
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return d < thr;
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}
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/// Derives the dot product of two vectors on the xz-plane. (@p u . @p v)
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/// @param[in] u A vector [(x, y, z)]
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/// @param[in] v A vector [(x, y, z)]
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/// @return The dot product on the xz-plane.
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///
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/// The vectors are projected onto the xz-plane, so the y-values are ignored.
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inline float dtVdot2D(const float* u, const float* v)
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{
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return u[0]*v[0] + u[2]*v[2];
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}
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/// Derives the xz-plane 2D perp product of the two vectors. (uz*vx - ux*vz)
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/// @param[in] u The LHV vector [(x, y, z)]
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/// @param[in] v The RHV vector [(x, y, z)]
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/// @return The dot product on the xz-plane.
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///
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/// The vectors are projected onto the xz-plane, so the y-values are ignored.
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inline float dtVperp2D(const float* u, const float* v)
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{
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return u[2]*v[0] - u[0]*v[2];
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}
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/// @}
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/// @name Computational geometry helper functions.
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/// @{
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/// Derives the signed xz-plane area of the triangle ABC, or the relationship of line AB to point C.
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/// @param[in] a Vertex A. [(x, y, z)]
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/// @param[in] b Vertex B. [(x, y, z)]
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/// @param[in] c Vertex C. [(x, y, z)]
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/// @return The signed xz-plane area of the triangle.
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inline float dtTriArea2D(const float* a, const float* b, const float* c)
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{
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const float abx = b[0] - a[0];
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const float abz = b[2] - a[2];
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const float acx = c[0] - a[0];
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const float acz = c[2] - a[2];
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return acx*abz - abx*acz;
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}
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/// Determines if two axis-aligned bounding boxes overlap.
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/// @param[in] amin Minimum bounds of box A. [(x, y, z)]
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/// @param[in] amax Maximum bounds of box A. [(x, y, z)]
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/// @param[in] bmin Minimum bounds of box B. [(x, y, z)]
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/// @param[in] bmax Maximum bounds of box B. [(x, y, z)]
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/// @return True if the two AABB's overlap.
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/// @see dtOverlapBounds
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inline bool dtOverlapQuantBounds(const unsigned short amin[3], const unsigned short amax[3],
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const unsigned short bmin[3], const unsigned short bmax[3])
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{
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bool overlap = true;
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overlap = (amin[0] > bmax[0] || amax[0] < bmin[0]) ? false : overlap;
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overlap = (amin[1] > bmax[1] || amax[1] < bmin[1]) ? false : overlap;
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overlap = (amin[2] > bmax[2] || amax[2] < bmin[2]) ? false : overlap;
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return overlap;
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}
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/// Determines if two axis-aligned bounding boxes overlap.
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/// @param[in] amin Minimum bounds of box A. [(x, y, z)]
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/// @param[in] amax Maximum bounds of box A. [(x, y, z)]
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/// @param[in] bmin Minimum bounds of box B. [(x, y, z)]
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/// @param[in] bmax Maximum bounds of box B. [(x, y, z)]
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/// @return True if the two AABB's overlap.
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/// @see dtOverlapQuantBounds
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inline bool dtOverlapBounds(const float* amin, const float* amax,
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const float* bmin, const float* bmax)
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{
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bool overlap = true;
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overlap = (amin[0] > bmax[0] || amax[0] < bmin[0]) ? false : overlap;
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overlap = (amin[1] > bmax[1] || amax[1] < bmin[1]) ? false : overlap;
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overlap = (amin[2] > bmax[2] || amax[2] < bmin[2]) ? false : overlap;
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return overlap;
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}
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/// Derives the closest point on a triangle from the specified reference point.
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/// @param[out] closest The closest point on the triangle.
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/// @param[in] p The reference point from which to test. [(x, y, z)]
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/// @param[in] a Vertex A of triangle ABC. [(x, y, z)]
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/// @param[in] b Vertex B of triangle ABC. [(x, y, z)]
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/// @param[in] c Vertex C of triangle ABC. [(x, y, z)]
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void dtClosestPtPointTriangle(float* closest, const float* p,
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const float* a, const float* b, const float* c);
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/// Derives the y-axis height of the closest point on the triangle from the specified reference point.
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/// @param[in] p The reference point from which to test. [(x, y, z)]
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/// @param[in] a Vertex A of triangle ABC. [(x, y, z)]
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/// @param[in] b Vertex B of triangle ABC. [(x, y, z)]
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/// @param[in] c Vertex C of triangle ABC. [(x, y, z)]
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/// @param[out] h The resulting height.
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bool dtClosestHeightPointTriangle(const float* p, const float* a, const float* b, const float* c, float& h);
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bool dtIntersectSegmentPoly2D(const float* p0, const float* p1,
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const float* verts, int nverts,
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float& tmin, float& tmax,
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int& segMin, int& segMax);
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bool dtIntersectSegSeg2D(const float* ap, const float* aq,
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const float* bp, const float* bq,
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float& s, float& t);
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/// Determines if the specified point is inside the convex polygon on the xz-plane.
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/// @param[in] pt The point to check. [(x, y, z)]
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/// @param[in] verts The polygon vertices. [(x, y, z) * @p nverts]
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/// @param[in] nverts The number of vertices. [Limit: >= 3]
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/// @return True if the point is inside the polygon.
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bool dtPointInPolygon(const float* pt, const float* verts, const int nverts);
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bool dtDistancePtPolyEdgesSqr(const float* pt, const float* verts, const int nverts,
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float* ed, float* et);
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float dtDistancePtSegSqr2D(const float* pt, const float* p, const float* q, float& t);
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/// Derives the centroid of a convex polygon.
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/// @param[out] tc The centroid of the polgyon. [(x, y, z)]
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/// @param[in] idx The polygon indices. [(vertIndex) * @p nidx]
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/// @param[in] nidx The number of indices in the polygon. [Limit: >= 3]
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/// @param[in] verts The polygon vertices. [(x, y, z) * vertCount]
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void dtCalcPolyCenter(float* tc, const unsigned short* idx, int nidx, const float* verts);
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/// Determines if the two convex polygons overlap on the xz-plane.
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/// @param[in] polya Polygon A vertices. [(x, y, z) * @p npolya]
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/// @param[in] npolya The number of vertices in polygon A.
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/// @param[in] polyb Polygon B vertices. [(x, y, z) * @p npolyb]
|
|
/// @param[in] npolyb The number of vertices in polygon B.
|
|
/// @return True if the two polygons overlap.
|
|
bool dtOverlapPolyPoly2D(const float* polya, const int npolya,
|
|
const float* polyb, const int npolyb);
|
|
|
|
/// @}
|
|
/// @name Miscellanious functions.
|
|
/// @{
|
|
|
|
inline unsigned int dtNextPow2(unsigned int v)
|
|
{
|
|
v--;
|
|
v |= v >> 1;
|
|
v |= v >> 2;
|
|
v |= v >> 4;
|
|
v |= v >> 8;
|
|
v |= v >> 16;
|
|
v++;
|
|
return v;
|
|
}
|
|
|
|
inline unsigned int dtIlog2(unsigned int v)
|
|
{
|
|
unsigned int r;
|
|
unsigned int shift;
|
|
r = (v > 0xffff) << 4; v >>= r;
|
|
shift = (v > 0xff) << 3; v >>= shift; r |= shift;
|
|
shift = (v > 0xf) << 2; v >>= shift; r |= shift;
|
|
shift = (v > 0x3) << 1; v >>= shift; r |= shift;
|
|
r |= (v >> 1);
|
|
return r;
|
|
}
|
|
|
|
inline int dtAlign4(int x) { return (x+3) & ~3; }
|
|
|
|
inline int dtOppositeTile(int side) { return (side+4) & 0x7; }
|
|
|
|
inline void dtSwapByte(unsigned char* a, unsigned char* b)
|
|
{
|
|
unsigned char tmp = *a;
|
|
*a = *b;
|
|
*b = tmp;
|
|
}
|
|
|
|
inline void dtSwapEndian(unsigned short* v)
|
|
{
|
|
unsigned char* x = (unsigned char*)v;
|
|
dtSwapByte(x+0, x+1);
|
|
}
|
|
|
|
inline void dtSwapEndian(short* v)
|
|
{
|
|
unsigned char* x = (unsigned char*)v;
|
|
dtSwapByte(x+0, x+1);
|
|
}
|
|
|
|
inline void dtSwapEndian(unsigned int* v)
|
|
{
|
|
unsigned char* x = (unsigned char*)v;
|
|
dtSwapByte(x+0, x+3); dtSwapByte(x+1, x+2);
|
|
}
|
|
|
|
inline void dtSwapEndian(int* v)
|
|
{
|
|
unsigned char* x = (unsigned char*)v;
|
|
dtSwapByte(x+0, x+3); dtSwapByte(x+1, x+2);
|
|
}
|
|
|
|
inline void dtSwapEndian(float* v)
|
|
{
|
|
unsigned char* x = (unsigned char*)v;
|
|
dtSwapByte(x+0, x+3); dtSwapByte(x+1, x+2);
|
|
}
|
|
|
|
void dtRandomPointInConvexPoly(const float* pts, const int npts, float* areas,
|
|
const float s, const float t, float* out);
|
|
|
|
template<typename TypeToRetrieveAs>
|
|
TypeToRetrieveAs* dtGetThenAdvanceBufferPointer(const unsigned char*& buffer, const size_t distanceToAdvance)
|
|
{
|
|
TypeToRetrieveAs* returnPointer = reinterpret_cast<TypeToRetrieveAs*>(buffer);
|
|
buffer += distanceToAdvance;
|
|
return returnPointer;
|
|
}
|
|
|
|
template<typename TypeToRetrieveAs>
|
|
TypeToRetrieveAs* dtGetThenAdvanceBufferPointer(unsigned char*& buffer, const size_t distanceToAdvance)
|
|
{
|
|
TypeToRetrieveAs* returnPointer = reinterpret_cast<TypeToRetrieveAs*>(buffer);
|
|
buffer += distanceToAdvance;
|
|
return returnPointer;
|
|
}
|
|
|
|
|
|
/// @}
|
|
|
|
#endif // DETOURCOMMON_H
|
|
|
|
///////////////////////////////////////////////////////////////////////////
|
|
|
|
// This section contains detailed documentation for members that don't have
|
|
// a source file. It reduces clutter in the main section of the header.
|
|
|
|
/**
|
|
|
|
@fn float dtTriArea2D(const float* a, const float* b, const float* c)
|
|
@par
|
|
|
|
The vertices are projected onto the xz-plane, so the y-values are ignored.
|
|
|
|
This is a low cost function than can be used for various purposes. Its main purpose
|
|
is for point/line relationship testing.
|
|
|
|
In all cases: A value of zero indicates that all vertices are collinear or represent the same point.
|
|
(On the xz-plane.)
|
|
|
|
When used for point/line relationship tests, AB usually represents a line against which
|
|
the C point is to be tested. In this case:
|
|
|
|
A positive value indicates that point C is to the left of line AB, looking from A toward B.<br/>
|
|
A negative value indicates that point C is to the right of lineAB, looking from A toward B.
|
|
|
|
When used for evaluating a triangle:
|
|
|
|
The absolute value of the return value is two times the area of the triangle when it is
|
|
projected onto the xz-plane.
|
|
|
|
A positive return value indicates:
|
|
|
|
<ul>
|
|
<li>The vertices are wrapped in the normal Detour wrap direction.</li>
|
|
<li>The triangle's 3D face normal is in the general up direction.</li>
|
|
</ul>
|
|
|
|
A negative return value indicates:
|
|
|
|
<ul>
|
|
<li>The vertices are reverse wrapped. (Wrapped opposite the normal Detour wrap direction.)</li>
|
|
<li>The triangle's 3D face normal is in the general down direction.</li>
|
|
</ul>
|
|
|
|
*/
|