X-Git-Url: http://git.xonotic.org/?a=blobdiff_plain;f=mathlib.c;h=ed0a43c60d3869c735dad47f6495f50afa47928d;hb=aa18f6ecab09516f2af3bf710fc4c9090634d3c3;hp=eaa1a765d8e05bc5c65328a808591ad5053941e1;hpb=da29a8beeb35293e2fd38b51883c91b5cf4cf4ad;p=xonotic%2Fdarkplaces.git

diff --git a/mathlib.c b/mathlib.c
index eaa1a765..ed0a43c6 100644
--- a/mathlib.c
+++ b/mathlib.c
@@ -19,9 +19,10 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */
 // mathlib.c -- math primitives
 
-#include <math.h>
 #include "quakedef.h"
 
+#include <math.h>
+
 vec3_t vec3_origin = {0,0,0};
 float ixtable[4096];
 
@@ -202,11 +203,16 @@ void VectorVectors(const vec3_t forward, vec3_t right, vec3_t up)
 	right[0] = forward[2];
 	right[1] = -forward[0];
 	right[2] = forward[1];
+	// BUG!
+	//   assume forward = {sqrt(1/3), sqrt(1/3), -sqrt(1/3)}
+	//   then right will be {-sqrt(1/3), -sqrt(1/3), sqrt(1/3)}
+	//   PROBLEM?
 
 	d = DotProduct(forward, right);
 	VectorMA(right, -d, forward, right);
 	VectorNormalize(right);
 	CrossProduct(right, forward, up);
+	VectorNormalize(up); // CrossProduct in this case returns 'up thats length is not 1
 }
 
 void VectorVectorsDouble(const double *forward, double *right, double *up)
@@ -517,6 +523,82 @@ void AngleVectorsFLU (const vec3_t angles, vec3_t forward, vec3_t left, vec3_t u
 	}
 }
 
+// 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)
+{
+	if (forward[0] == 0 && forward[1] == 0)
+	{
+		if(forward[2] > 0)
+		{
+			angles[PITCH] = -M_PI * 0.5;
+			angles[YAW] = up ? atan2(-up[1], -up[0]) : 0;
+		}
+		else
+		{
+			angles[PITCH] = M_PI * 0.5;
+			angles[YAW] = up ? atan2(up[1], up[0]) : 0;
+		}
+		angles[ROLL] = 0;
+	}
+	else
+	{
+		angles[YAW] = atan2(forward[1], forward[0]);
+		angles[PITCH] = -atan2(forward[2], sqrt(forward[0]*forward[0] + forward[1]*forward[1]));
+		if (up)
+		{
+			vec_t cp = cos(angles[PITCH]), sp = sin(angles[PITCH]);
+			vec_t cy = cos(angles[YAW]), sy = sin(angles[YAW]);
+			vec3_t tleft, tup;
+			tleft[0] = -sy;
+			tleft[1] = cy;
+			tleft[2] = 0;
+			tup[0] = sp*cy;
+			tup[1] = sp*sy;
+			tup[2] = cp;
+			angles[ROLL] = -atan2(DotProduct(up, tleft), DotProduct(up, tup));
+		}
+		else
+			angles[ROLL] = 0;
+	}
+
+	// now convert radians to degrees, and make all values positive
+	VectorScale(angles, 180.0 / M_PI, angles);
+	if (flippitch)
+		angles[PITCH] *= -1;
+	if (angles[PITCH] < 0) angles[PITCH] += 360;
+	if (angles[YAW] < 0) angles[YAW] += 360;
+	if (angles[ROLL] < 0) angles[ROLL] += 360;
+
+#if 0
+{
+	// debugging code
+	vec3_t tforward, tleft, tup, nforward, nup;
+	VectorCopy(forward, nforward);
+	VectorNormalize(nforward);
+	if (up)
+	{
+		VectorCopy(up, nup);
+		VectorNormalize(nup);
+		AngleVectors(angles, tforward, tleft, tup);
+		if (VectorDistance(tforward, nforward) > 0.01 || VectorDistance(tup, nup) > 0.01)
+		{
+			Con_Printf("vectoangles('%f %f %f', '%f %f %f') = %f %f %f\n", nforward[0], nforward[1], nforward[2], nup[0], nup[1], nup[2], angles[0], angles[1], angles[2]);
+			Con_Printf("^3But that is '%f %f %f', '%f %f %f'\n", tforward[0], tforward[1], tforward[2], tup[0], tup[1], tup[2]);
+		}
+	}
+	else
+	{
+		AngleVectors(angles, tforward, tleft, tup);
+		if (VectorDistance(tforward, nforward) > 0.01)
+		{
+			Con_Printf("vectoangles('%f %f %f') = %f %f %f\n", nforward[0], nforward[1], nforward[2], angles[0], angles[1], angles[2]);
+			Con_Printf("^3But that is '%f %f %f'\n", tforward[0], tforward[1], tforward[2]);
+		}
+	}
+}
+#endif
+}
+
 #if 0
 void AngleMatrix (const vec3_t angles, const vec3_t translate, vec_t matrix[][4])
 {
@@ -679,3 +761,12 @@ void BoxFromPoints(vec3_t mins, vec3_t maxs, int numpoints, vec_t *point3f)
 	}
 }
 
+// LordHavoc: this has to be done right or you get severe precision breakdown
+int LoopingFrameNumberFromDouble(double t, int loopframes)
+{
+	if (loopframes)
+		return (int)(t - floor(t/loopframes)*loopframes);
+	else
+		return (int)t;
+}
+