Optimize VectorNormalize macros by not doing the sqrt on 0 length, this also means...

[xonotic/darkplaces.git] / mathlib.h

diff --git a/mathlib.h b/mathlib.h
index cb674e51a38affd019b3f023ad9e038f824da038..e953333545fcb93fff94be815a979fdd58fe5285 100644 (file)
--- a/mathlib.h
+++ b/mathlib.h
@@ -55,7 +55,7 @@ extern vec3_t vec3_origin;
 #define max(A,B) ((A) > (B) ? (A) : (B))
 #endif
 
-/// LordHavoc: this function never returns exactly MIN or exactly MAX, because
+/// LadyHavoc: this function never returns exactly MIN or exactly MAX, because
 /// of a QuakeC bug in id1 where the line
 /// self.nextthink = self.nexthink + random() * 0.5;
 /// can result in 0 (self.nextthink is 0 at this point in the code to begin
@@ -83,6 +83,8 @@ unsigned int CeilPowerOf2(unsigned int value);
 #define RAD2DEG(a) ((a) * (180.0f / (float) M_PI))
 #define ANGLEMOD(a) ((a) - 360.0 * floor((a) / 360.0))
 
+#define Q_rint(x) ((x) > 0 ? (int)((x) + 0.5) : (int)((x) - 0.5)) //johnfitz -- from joequake
+
 #define DotProduct2(a,b) ((a)[0]*(b)[0]+(a)[1]*(b)[1])
 #define Vector2Clear(a) ((a)[0]=(a)[1]=0)
 #define Vector2Compare(a,b) (((a)[0]==(b)[0])&&((a)[1]==(b)[1]))
@@ -90,7 +92,7 @@ unsigned int CeilPowerOf2(unsigned int value);
 #define Vector2Negate(a,b) ((b)[0]=-((a)[0]),(b)[1]=-((a)[1]))
 #define Vector2Set(a,b,c) ((a)[0]=(b),(a)[1]=(c))
 #define Vector2Scale(in, scale, out) ((out)[0] = (in)[0] * (scale),(out)[1] = (in)[1] * (scale))
-#define Vector2Normalize2(v,dest) {float ilength = (float) sqrt(DotProduct2((v),(v)));if (ilength) ilength = 1.0f / ilength;dest[0] = (v)[0] * ilength;dest[1] = (v)[1] * ilength;}
+#define Vector2Normalize2(v,dest) {float ilength = (float)DotProduct2((v),(v));if (ilength) ilength = 1.0f / sqrt(ilength);dest[0] = (v)[0] * ilength;dest[1] = (v)[1] * ilength;}
 
 #define DotProduct4(a,b) ((a)[0]*(b)[0]+(a)[1]*(b)[1]+(a)[2]*(b)[2]+(a)[3]*(b)[3])
 #define Vector4Clear(a) ((a)[0]=(a)[1]=(a)[2]=(a)[3]=0)
@@ -98,7 +100,7 @@ unsigned int CeilPowerOf2(unsigned int value);
 #define Vector4Copy(a,b) ((b)[0]=(a)[0],(b)[1]=(a)[1],(b)[2]=(a)[2],(b)[3]=(a)[3])
 #define Vector4Negate(a,b) ((b)[0]=-((a)[0]),(b)[1]=-((a)[1]),(b)[2]=-((a)[2]),(b)[3]=-((a)[3]))
 #define Vector4Set(a,b,c,d,e) ((a)[0]=(b),(a)[1]=(c),(a)[2]=(d),(a)[3]=(e))
-#define Vector4Normalize2(v,dest) {float ilength = (float) sqrt(DotProduct4((v),(v)));if (ilength) ilength = 1.0f / ilength;dest[0] = (v)[0] * ilength;dest[1] = (v)[1] * ilength;dest[2] = (v)[2] * ilength;dest[3] = (v)[3] * ilength;}
+#define Vector4Normalize2(v,dest) {float ilength = (float)DotProduct4((v),(v));if (ilength) ilength = 1.0f / sqrt(ilength);dest[0] = (v)[0] * ilength;dest[1] = (v)[1] * ilength;dest[2] = (v)[2] * ilength;dest[3] = (v)[3] * ilength;}
 #define Vector4Subtract(a,b,c) ((c)[0]=(a)[0]-(b)[0],(c)[1]=(a)[1]-(b)[1],(c)[2]=(a)[2]-(b)[2],(c)[3]=(a)[3]-(b)[3])
 #define Vector4Add(a,b,c) ((c)[0]=(a)[0]+(b)[0],(c)[1]=(a)[1]+(b)[1],(c)[2]=(a)[2]+(b)[2],(c)[3]=(a)[3]+(b)[3])
 #define Vector4Scale(in, scale, out) ((out)[0] = (in)[0] * (scale),(out)[1] = (in)[1] * (scale),(out)[2] = (in)[2] * (scale),(out)[3] = (in)[3] * (scale))
@@ -115,9 +117,9 @@ unsigned int CeilPowerOf2(unsigned int value);
 #define VectorCopy(a,b) ((b)[0]=(a)[0],(b)[1]=(a)[1],(b)[2]=(a)[2])
 #define VectorMultiply(a,b,c) ((c)[0]=(a)[0]*(b)[0],(c)[1]=(a)[1]*(b)[1],(c)[2]=(a)[2]*(b)[2])
 #define CrossProduct(a,b,c) ((c)[0]=(a)[1]*(b)[2]-(a)[2]*(b)[1],(c)[1]=(a)[2]*(b)[0]-(a)[0]*(b)[2],(c)[2]=(a)[0]*(b)[1]-(a)[1]*(b)[0])
-#define VectorNormalize(v) {float ilength = (float) sqrt(DotProduct((v),(v)));if (ilength) ilength = 1.0f / ilength;(v)[0] *= ilength;(v)[1] *= ilength;(v)[2] *= ilength;}
-#define VectorNormalize2(v,dest) {float ilength = (float) sqrt(DotProduct((v),(v)));if (ilength) ilength = 1.0f / ilength;dest[0] = (v)[0] * ilength;dest[1] = (v)[1] * ilength;dest[2] = (v)[2] * ilength;}
-#define VectorNormalizeDouble(v) {double ilength = sqrt(DotProduct((v),(v)));if (ilength) ilength = 1.0 / ilength;(v)[0] *= ilength;(v)[1] *= ilength;(v)[2] *= ilength;}
+#define VectorNormalize(v) {float ilength = (float)DotProduct((v),(v));if (ilength) ilength = 1.0f / sqrt(ilength);(v)[0] *= ilength;(v)[1] *= ilength;(v)[2] *= ilength;}
+#define VectorNormalize2(v,dest) {float ilength = (float)DotProduct((v),(v));if (ilength) ilength = 1.0f / sqrt(ilength);dest[0] = (v)[0] * ilength;dest[1] = (v)[1] * ilength;dest[2] = (v)[2] * ilength;}
+#define VectorNormalizeDouble(v) {double ilength = DotProduct((v),(v));if (ilength) ilength = 1.0 / sqrt(ilength);(v)[0] *= ilength;(v)[1] *= ilength;(v)[2] *= ilength;}
 #define VectorDistance2(a, b) (((a)[0] - (b)[0]) * ((a)[0] - (b)[0]) + ((a)[1] - (b)[1]) * ((a)[1] - (b)[1]) + ((a)[2] - (b)[2]) * ((a)[2] - (b)[2]))
 #define VectorDistance(a, b) (sqrt(VectorDistance2(a,b)))
 #define VectorLength(a) (sqrt((double)DotProduct(a, a)))
@@ -181,15 +183,16 @@ int PointInfrontOfTriangle(const float *p, const float *a, const float *b, const
 }
 #endif
 
-#define lhcheeserand() (seed = (seed * 987211u) ^ (seed >> 13u) ^ 914867)
-#define lhcheeserandom(MIN,MAX) ((double)(lhcheeserand() + 0.5) / ((double)4096.0*1024.0*1024.0) * ((MAX)-(MIN)) + (MIN))
-#define VectorCheeseRandom(v) do{(v)[0] = lhcheeserandom(-1, 1);(v)[1] = lhcheeserandom(-1, 1);(v)[2] = lhcheeserandom(-1, 1);}while(DotProduct(v, v) > 1)
+#define lhcheeserand(seed) ((seed) = ((seed) * 987211u) ^ ((seed) >> 13u) ^ 914867)
+#define lhcheeserandom(seed,MIN,MAX) ((double)(lhcheeserand(seed) + 0.5) / ((double)4096.0*1024.0*1024.0) * ((MAX)-(MIN)) + (MIN))
+#define VectorCheeseRandom(seed,v) do{(v)[0] = lhcheeserandom(seed,-1, 1);(v)[1] = lhcheeserandom(seed,-1, 1);(v)[2] = lhcheeserandom(seed,-1, 1);}while(DotProduct(v, v) > 1)
+#define VectorLehmerRandom(seed,v) do{(v)[0] = Math_crandomf(seed);(v)[1] = Math_crandomf(seed);(v)[2] = Math_crandomf(seed);}while(DotProduct(v, v) > 1)
 
 /*
-// LordHavoc: quaternion math, untested, don't know if these are correct,
+// LadyHavoc: quaternion math, untested, don't know if these are correct,
 // need to add conversion to/from matrices
-// LordHavoc: later note: the matrix faq is useful: http://skal.planet-d.net/demo/matrixfaq.htm
-// LordHavoc: these are probably very wrong and I'm not sure I care, not used by anything
+// LadyHavoc: later note: the matrix faq is useful: http://skal.planet-d.net/demo/matrixfaq.htm
+// LadyHavoc: these are probably very wrong and I'm not sure I care, not used by anything
 
 // returns length of quaternion
 #define qlen(a) ((float) sqrt((a)[0]*(a)[0]+(a)[1]*(a)[1]+(a)[2]*(a)[2]+(a)[3]*(a)[3]))
@@ -232,14 +235,9 @@ float r2is = 1.0f / sin(r2);\
 
 #define VectorCopy4(a,b) {(b)[0]=(a)[0];(b)[1]=(a)[1];(b)[2]=(a)[2];(b)[3]=(a)[3];}
 
-vec_t Length (vec3_t v);
-
 /// returns vector length
 float VectorNormalizeLength (vec3_t v);
 
-/// returns vector length
-float VectorNormalizeLength2 (vec3_t v, vec3_t dest);
-
 #define NUMVERTEXNORMALS       162
 extern float m_bytenormals[NUMVERTEXNORMALS][3];
 
@@ -250,16 +248,16 @@ void R_ConcatRotations (const float in1[3*3], const float in2[3*3], float out[3*
 void R_ConcatTransforms (const float in1[3*4], const float in2[3*4], float out[3*4]);
 
 void AngleVectors (const vec3_t angles, vec3_t forward, vec3_t right, vec3_t up);
-/// LordHavoc: proper matrix version of AngleVectors
+/// LadyHavoc: proper matrix version of AngleVectors
 void AngleVectorsFLU (const vec3_t angles, vec3_t forward, vec3_t left, vec3_t up);
 /// divVerent: improper matrix version of AngleVectors
 void AngleVectorsDuke3DFLU (const vec3_t angles, vec3_t forward, vec3_t left, vec3_t up, double maxShearAngle);
-/// LordHavoc: builds a [3][4] matrix
+/// LadyHavoc: builds a [3][4] matrix
 void AngleMatrix (const vec3_t angles, const vec3_t translate, vec_t matrix[][4]);
-/// LordHavoc: calculates pitch/yaw/roll angles from forward and up vectors
-void AnglesFromVectors (vec3_t angles, const vec3_t forward, const vec3_t up, qboolean flippitch);
+/// LadyHavoc: calculates pitch/yaw/roll angles from forward and up vectors
+void AnglesFromVectors (vec3_t angles, const vec3_t forward, const vec3_t up, qbool flippitch);
 
-/// LordHavoc: like AngleVectors, but taking a forward vector instead of angles, useful!
+/// LadyHavoc: like AngleVectors, but taking a forward vector instead of angles, useful!
 void VectorVectors(const vec3_t forward, vec3_t right, vec3_t up);
 void VectorVectorsDouble(const double *forward, double *right, double *up);
 
@@ -274,7 +272,7 @@ void BoxPlaneCornerDistances_Separate(const vec3_t emins, const vec3_t emaxs, co
 #define PlaneDist(point,plane)  ((plane)->type < 3 ? (point)[(plane)->type] : DotProduct((point), (plane)->normal))
 #define PlaneDiff(point,plane) (((plane)->type < 3 ? (point)[(plane)->type] : DotProduct((point), (plane)->normal)) - (plane)->dist)
 
-/// LordHavoc: minimal plane structure
+/// LadyHavoc: minimal plane structure
 typedef struct tinyplane_s
 {
        float normal[3], dist;
@@ -301,6 +299,22 @@ void BoxFromPoints(vec3_t mins, vec3_t maxs, int numpoints, vec_t *point3f);
 
 int LoopingFrameNumberFromDouble(double t, int loopframes);
 
+// implementation of 128bit Lehmer Random Number Generator with 2^126 period
+// https://en.wikipedia.org/Lehmer_random_number_generator
+typedef struct randomseed_s
+{
+       unsigned int s[4];
+}
+randomseed_t;
+
+void Math_RandomSeed_Reset(randomseed_t *r);
+void Math_RandomSeed_FromInts(randomseed_t *r, unsigned int s0, unsigned int s1, unsigned int s2, unsigned int s3);
+unsigned long long Math_rand64(randomseed_t *r);
+float Math_randomf(randomseed_t *r);
+float Math_crandomf(randomseed_t *r);
+float Math_randomrangef(randomseed_t *r, float minf, float maxf);
+int Math_randomrangei(randomseed_t *r, int mini, int maxi);
+
 void Mathlib_Init(void);
 
 #endif