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New fixed math functions - ClosestPointOnVector, and Strength.

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Normal also returns length now, since it is free.
This commit is contained in:
Arthur 2018-12-15 08:46:08 -05:00 committed by mazmazz
parent 1029463741
commit c4d5afdd80
2 changed files with 140 additions and 103 deletions
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39
src/m_fixed.c
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@ -458,6 +458,20 @@ vector3_t *FV3_ClosestPointOnLine(const vector3_t *Line, const vector3_t *p, vec
return FV3_AddEx(&Line[0], &V, out); return FV3_AddEx(&Line[0], &V, out);
} }
//
// ClosestPointOnVector
//
// Similar to ClosestPointOnLine, but uses a vector instead of two points.
//
void FV3_ClosestPointOnVector(const vector3_t *dir, const vector3_t *p, vector3_t *out)
{
fixed_t t = FV3_Dot(dir, p);
// Return the point on the line closest
FV3_MulEx(dir, t, out);
return;
}
// //
// ClosestPointOnTriangle // ClosestPointOnTriangle
// //
@ -519,7 +533,7 @@ vector3_t *FV3_Point2Vec (const vector3_t *point1, const vector3_t *point2, vect
// //
// Calculates the normal of a polygon. // Calculates the normal of a polygon.
// //
void FV3_Normal (const vector3_t *a_triangle, vector3_t *a_normal) fixed_t FV3_Normal(const vector3_t *a_triangle, vector3_t *a_normal)
{ {
vector3_t a_1; vector3_t a_1;
vector3_t a_2; vector3_t a_2;
@ -529,7 +543,28 @@ void FV3_Normal (const vector3_t *a_triangle, vector3_t *a_normal)
FV3_Cross(&a_1, &a_2, a_normal); FV3_Cross(&a_1, &a_2, a_normal);
FV3_NormalizeEx(a_normal, a_normal); return FV3_NormalizeEx(a_normal, a_normal);
}
//
// Strength
//
// Measures the 'strength' of a vector in a particular direction.
//
fixed_t FV3_Strength(const vector3_t *a_1, const vector3_t *dir)
{
vector3_t normal;
fixed_t dist = FV3_NormalizeEx(a_1, &normal);
fixed_t dot = FV3_Dot(&normal, dir);
FV3_ClosestPointOnVector(dir, a_1, &normal);
dist = FV3_Magnitude(&normal);
if (dot < 0) // Not facing same direction, so negate result.
dist = -dist;
return dist;
} }
// //

4
src/m_fixed.h
View file

@ -394,9 +394,11 @@ boolean FV3_Equal(const vector3_t *a_1, const vector3_t *a_2);
fixed_t FV3_Dot(const vector3_t *a_1, const vector3_t *a_2); fixed_t FV3_Dot(const vector3_t *a_1, const vector3_t *a_2);
vector3_t *FV3_Cross(const vector3_t *a_1, const vector3_t *a_2, vector3_t *a_o); vector3_t *FV3_Cross(const vector3_t *a_1, const vector3_t *a_2, vector3_t *a_o);
vector3_t *FV3_ClosestPointOnLine(const vector3_t *Line, const vector3_t *p, vector3_t *out); vector3_t *FV3_ClosestPointOnLine(const vector3_t *Line, const vector3_t *p, vector3_t *out);
void FV3_ClosestPointOnVector(const vector3_t *dir, const vector3_t *p, vector3_t *out);
void FV3_ClosestPointOnTriangle(const vector3_t *tri, const vector3_t *point, vector3_t *result); void FV3_ClosestPointOnTriangle(const vector3_t *tri, const vector3_t *point, vector3_t *result);
vector3_t *FV3_Point2Vec(const vector3_t *point1, const vector3_t *point2, vector3_t *a_o); vector3_t *FV3_Point2Vec(const vector3_t *point1, const vector3_t *point2, vector3_t *a_o);
void FV3_Normal(const vector3_t *a_triangle, vector3_t *a_normal); fixed_t FV3_Normal(const vector3_t *a_triangle, vector3_t *a_normal);
fixed_t FV3_Strength(const vector3_t *a_1, const vector3_t *dir);
fixed_t FV3_PlaneDistance(const vector3_t *a_normal, const vector3_t *a_point); fixed_t FV3_PlaneDistance(const vector3_t *a_normal, const vector3_t *a_point);
boolean FV3_IntersectedPlane(const vector3_t *a_triangle, const vector3_t *a_line, vector3_t *a_normal, fixed_t *originDistance); boolean FV3_IntersectedPlane(const vector3_t *a_triangle, const vector3_t *a_line, vector3_t *a_normal, fixed_t *originDistance);
fixed_t FV3_PlaneIntersection(const vector3_t *pOrigin, const vector3_t *pNormal, const vector3_t *rOrigin, const vector3_t *rVector); fixed_t FV3_PlaneIntersection(const vector3_t *pOrigin, const vector3_t *pNormal, const vector3_t *rOrigin, const vector3_t *rVector);