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line cross line func added

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This commit is contained in:
Vladislav Khorev 2013-11-05 18:59:59 +00:00
parent 327a15854c
commit 6d950cab56
2 changed files with 51 additions and 0 deletions
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1
include/Utils/DataTypes/DataTypes.h
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@ -82,6 +82,7 @@ int LineCrossTriangle(const vec3& a, const vec3& b, const TSmpTriangle& tr, vec3
int PointInTriangle(const vec3& q, const TSmpTriangle& tr);
int LineCrossLine2d(const vec2& a1, const vec2& a2, const vec2& b1, const vec2& b2, vec2& r);
template<typename T>
inline std::string tostr(T i)

50
src/Utils/DataTypes/DataTypes.cpp
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@ -307,6 +307,56 @@ int PointInTriangle(const vec3& q, const TSmpTriangle& tr)
}
int LineCrossLine2d(const vec2& a1, const vec2& a2, const vec2& b1, const vec2& b2, vec2& r)
{
vec2 v = (a2 - a1);
mat2 m;
m.m[0] = v.v[0];
m.m[1] = b1.v[0] - b2.v[0];
m.m[2] = v.v[1];
m.m[3] = b1.v[1] - b2.v[1];
float detm = m.m[0] * m.m[3] - m.m[1] * m.m[2];
if (fabs(detm) <= 0.00005f)
{
return -1;
}
mat2 ad_m;
ad_m.m[0] = m.m[3];
ad_m.m[1] = -m.m[2];
ad_m.m[2] = -m.m[1];
ad_m.m[3] = m.m[0];
mat2 rev_m;
rev_m.m[0] = ad_m.m[0]/detm;
rev_m.m[1] = ad_m.m[2]/detm;
rev_m.m[2] = ad_m.m[1]/detm;
rev_m.m[3] = ad_m.m[3]/detm;
vec2 t;
vec2 vx = (b1 - a1);
t.v[0] = vx.v[0] * rev_m.m[0] + vx.v[1] * rev_m.m[1];
t.v[1] = vx.v[0] * rev_m.m[2] + vx.v[1] * rev_m.m[3];
if (t.v[0] < 0 || t.v[0] > 1 || t.v[1] < 0 || t.v[1] > 1)
{
return 0;
}
r = a1 + v * t.v[0];
return 1;
}
float roundf(float r)
{
return (r > 0.0f) ? floorf(r + 0.5f) : ceilf(r - 0.5f);