use dynamic eye position-centered bouncegrid when rendering in dynamic
[xonotic/darkplaces.git] / mathlib.c
index 83f39a8..d6170d2 100644 (file)
--- 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];
 
@@ -113,7 +114,7 @@ float m_bytenormals[NUMVERTEXNORMALS][3] =
 };
 
 #if 0
-qbyte NormalToByte(const vec3_t n)
+unsigned char NormalToByte(const vec3_t n)
 {
        int i, best;
        float bestdistance, distance;
@@ -133,7 +134,7 @@ qbyte NormalToByte(const vec3_t n)
 }
 
 // note: uses byte partly to force unsigned for the validity check
-void ByteToNormal(qbyte num, vec3_t n)
+void ByteToNormal(unsigned char num, vec3_t n)
 {
        if (num < NUMVERTEXNORMALS)
                VectorCopy(m_bytenormals[num], n);
@@ -141,17 +142,6 @@ void ByteToNormal(qbyte num, vec3_t n)
                VectorClear(n); // FIXME: complain?
 }
 
-float Q_RSqrt(float number)
-{
-       float y;
-
-       if (number == 0.0f)
-               return 0.0f;
-
-       *((int *)&y) = 0x5f3759df - ((* (int *) &number) >> 1);
-       return y * (1.5f - (number * 0.5f * y * y));
-}
-
 // assumes "src" is normalized
 void PerpendicularVector( vec3_t dst, const vec3_t src )
 {
@@ -215,10 +205,8 @@ void VectorVectors(const vec3_t forward, vec3_t right, vec3_t up)
        right[2] = forward[1];
 
        d = DotProduct(forward, right);
-       right[0] -= d * forward[0];
-       right[1] -= d * forward[1];
-       right[2] -= d * forward[2];
-       VectorNormalizeFast(right);
+       VectorMA(right, -d, forward, right);
+       VectorNormalize(right);
        CrossProduct(right, forward, up);
 }
 
@@ -231,9 +219,7 @@ void VectorVectorsDouble(const double *forward, double *right, double *up)
        right[2] = forward[1];
 
        d = DotProduct(forward, right);
-       right[0] -= d * forward[0];
-       right[1] -= d * forward[1];
-       right[2] -= d * forward[2];
+       VectorMA(right, -d, forward, right);
        VectorNormalize(right);
        CrossProduct(right, forward, up);
 }
@@ -271,6 +257,24 @@ void RotatePointAroundVector( vec3_t dst, const vec3_t dir, const vec3_t point,
 
 /*-----------------------------------------------------------------*/
 
+// returns the smallest integer greater than or equal to "value", or 0 if "value" is too big
+unsigned int CeilPowerOf2(unsigned int value)
+{
+       unsigned int ceilvalue;
+
+       if (value > (1U << (sizeof(int) * 8 - 1)))
+               return 0;
+
+       ceilvalue = 1;
+       while (ceilvalue < value)
+               ceilvalue <<= 1;
+
+       return ceilvalue;
+}
+
+
+/*-----------------------------------------------------------------*/
+
 
 void PlaneClassify(mplane_t *p)
 {
@@ -293,29 +297,116 @@ void PlaneClassify(mplane_t *p)
                p->signbits |= 4;
 }
 
-int BoxOnPlaneSide (const vec3_t emins, const vec3_t emaxs, const mplane_t *p)
+int BoxOnPlaneSide(const vec3_t emins, const vec3_t emaxs, const mplane_t *p)
 {
        if (p->type < 3)
                return ((emaxs[p->type] >= p->dist) | ((emins[p->type] < p->dist) << 1));
        switch(p->signbits)
        {
        default:
-       case 0:
-               return (((p->normal[0]*emaxs[0] + p->normal[1]*emaxs[1] + p->normal[2]*emaxs[2]) >= p->dist) | (((p->normal[0]*emins[0] + p->normal[1]*emins[1] + p->normal[2]*emins[2]) < p->dist) << 1));
-       case 1:
-               return (((p->normal[0]*emins[0] + p->normal[1]*emaxs[1] + p->normal[2]*emaxs[2]) >= p->dist) | (((p->normal[0]*emaxs[0] + p->normal[1]*emins[1] + p->normal[2]*emins[2]) < p->dist) << 1));
-       case 2:
-               return (((p->normal[0]*emaxs[0] + p->normal[1]*emins[1] + p->normal[2]*emaxs[2]) >= p->dist) | (((p->normal[0]*emins[0] + p->normal[1]*emaxs[1] + p->normal[2]*emins[2]) < p->dist) << 1));
-       case 3:
-               return (((p->normal[0]*emins[0] + p->normal[1]*emins[1] + p->normal[2]*emaxs[2]) >= p->dist) | (((p->normal[0]*emaxs[0] + p->normal[1]*emaxs[1] + p->normal[2]*emins[2]) < p->dist) << 1));
-       case 4:
-               return (((p->normal[0]*emaxs[0] + p->normal[1]*emaxs[1] + p->normal[2]*emins[2]) >= p->dist) | (((p->normal[0]*emins[0] + p->normal[1]*emins[1] + p->normal[2]*emaxs[2]) < p->dist) << 1));
-       case 5:
-               return (((p->normal[0]*emins[0] + p->normal[1]*emaxs[1] + p->normal[2]*emins[2]) >= p->dist) | (((p->normal[0]*emaxs[0] + p->normal[1]*emins[1] + p->normal[2]*emaxs[2]) < p->dist) << 1));
-       case 6:
-               return (((p->normal[0]*emaxs[0] + p->normal[1]*emins[1] + p->normal[2]*emins[2]) >= p->dist) | (((p->normal[0]*emins[0] + p->normal[1]*emaxs[1] + p->normal[2]*emaxs[2]) < p->dist) << 1));
-       case 7:
-               return (((p->normal[0]*emins[0] + p->normal[1]*emins[1] + p->normal[2]*emins[2]) >= p->dist) | (((p->normal[0]*emaxs[0] + p->normal[1]*emaxs[1] + p->normal[2]*emaxs[2]) < p->dist) << 1));
+       case 0: return (((p->normal[0] * emaxs[0] + p->normal[1] * emaxs[1] + p->normal[2] * emaxs[2]) >= p->dist) | (((p->normal[0] * emins[0] + p->normal[1] * emins[1] + p->normal[2] * emins[2]) < p->dist) << 1));
+       case 1: return (((p->normal[0] * emins[0] + p->normal[1] * emaxs[1] + p->normal[2] * emaxs[2]) >= p->dist) | (((p->normal[0] * emaxs[0] + p->normal[1] * emins[1] + p->normal[2] * emins[2]) < p->dist) << 1));
+       case 2: return (((p->normal[0] * emaxs[0] + p->normal[1] * emins[1] + p->normal[2] * emaxs[2]) >= p->dist) | (((p->normal[0] * emins[0] + p->normal[1] * emaxs[1] + p->normal[2] * emins[2]) < p->dist) << 1));
+       case 3: return (((p->normal[0] * emins[0] + p->normal[1] * emins[1] + p->normal[2] * emaxs[2]) >= p->dist) | (((p->normal[0] * emaxs[0] + p->normal[1] * emaxs[1] + p->normal[2] * emins[2]) < p->dist) << 1));
+       case 4: return (((p->normal[0] * emaxs[0] + p->normal[1] * emaxs[1] + p->normal[2] * emins[2]) >= p->dist) | (((p->normal[0] * emins[0] + p->normal[1] * emins[1] + p->normal[2] * emaxs[2]) < p->dist) << 1));
+       case 5: return (((p->normal[0] * emins[0] + p->normal[1] * emaxs[1] + p->normal[2] * emins[2]) >= p->dist) | (((p->normal[0] * emaxs[0] + p->normal[1] * emins[1] + p->normal[2] * emaxs[2]) < p->dist) << 1));
+       case 6: return (((p->normal[0] * emaxs[0] + p->normal[1] * emins[1] + p->normal[2] * emins[2]) >= p->dist) | (((p->normal[0] * emins[0] + p->normal[1] * emaxs[1] + p->normal[2] * emaxs[2]) < p->dist) << 1));
+       case 7: return (((p->normal[0] * emins[0] + p->normal[1] * emins[1] + p->normal[2] * emins[2]) >= p->dist) | (((p->normal[0] * emaxs[0] + p->normal[1] * emaxs[1] + p->normal[2] * emaxs[2]) < p->dist) << 1));
+       }
+}
+
+#if 0
+int BoxOnPlaneSide_Separate(const vec3_t emins, const vec3_t emaxs, const vec3_t normal, const vec_t dist)
+{
+       switch((normal[0] < 0) | ((normal[1] < 0) << 1) | ((normal[2] < 0) << 2))
+       {
+       default:
+       case 0: return (((normal[0] * emaxs[0] + normal[1] * emaxs[1] + normal[2] * emaxs[2]) >= dist) | (((normal[0] * emins[0] + normal[1] * emins[1] + normal[2] * emins[2]) < dist) << 1));
+       case 1: return (((normal[0] * emins[0] + normal[1] * emaxs[1] + normal[2] * emaxs[2]) >= dist) | (((normal[0] * emaxs[0] + normal[1] * emins[1] + normal[2] * emins[2]) < dist) << 1));
+       case 2: return (((normal[0] * emaxs[0] + normal[1] * emins[1] + normal[2] * emaxs[2]) >= dist) | (((normal[0] * emins[0] + normal[1] * emaxs[1] + normal[2] * emins[2]) < dist) << 1));
+       case 3: return (((normal[0] * emins[0] + normal[1] * emins[1] + normal[2] * emaxs[2]) >= dist) | (((normal[0] * emaxs[0] + normal[1] * emaxs[1] + normal[2] * emins[2]) < dist) << 1));
+       case 4: return (((normal[0] * emaxs[0] + normal[1] * emaxs[1] + normal[2] * emins[2]) >= dist) | (((normal[0] * emins[0] + normal[1] * emins[1] + normal[2] * emaxs[2]) < dist) << 1));
+       case 5: return (((normal[0] * emins[0] + normal[1] * emaxs[1] + normal[2] * emins[2]) >= dist) | (((normal[0] * emaxs[0] + normal[1] * emins[1] + normal[2] * emaxs[2]) < dist) << 1));
+       case 6: return (((normal[0] * emaxs[0] + normal[1] * emins[1] + normal[2] * emins[2]) >= dist) | (((normal[0] * emins[0] + normal[1] * emaxs[1] + normal[2] * emaxs[2]) < dist) << 1));
+       case 7: return (((normal[0] * emins[0] + normal[1] * emins[1] + normal[2] * emins[2]) >= dist) | (((normal[0] * emaxs[0] + normal[1] * emaxs[1] + normal[2] * emaxs[2]) < dist) << 1));
+       }
+}
+#endif
+
+void BoxPlaneCorners(const vec3_t emins, const vec3_t emaxs, const mplane_t *p, vec3_t outnear, vec3_t outfar)
+{
+       if (p->type < 3)
+       {
+               outnear[0] = outnear[1] = outnear[2] = outfar[0] = outfar[1] = outfar[2] = 0;
+               outnear[p->type] = emins[p->type];
+               outfar[p->type] = emaxs[p->type];
+               return;
+       }
+       switch(p->signbits)
+       {
+       default:
+       case 0: outnear[0] = emaxs[0];outnear[1] = emaxs[1];outnear[2] = emaxs[2];outfar[0] = emins[0];outfar[1] = emins[1];outfar[2] = emins[2];break;
+       case 1: outnear[0] = emins[0];outnear[1] = emaxs[1];outnear[2] = emaxs[2];outfar[0] = emaxs[0];outfar[1] = emins[1];outfar[2] = emins[2];break;
+       case 2: outnear[0] = emaxs[0];outnear[1] = emins[1];outnear[2] = emaxs[2];outfar[0] = emins[0];outfar[1] = emaxs[1];outfar[2] = emins[2];break;
+       case 3: outnear[0] = emins[0];outnear[1] = emins[1];outnear[2] = emaxs[2];outfar[0] = emaxs[0];outfar[1] = emaxs[1];outfar[2] = emins[2];break;
+       case 4: outnear[0] = emaxs[0];outnear[1] = emaxs[1];outnear[2] = emins[2];outfar[0] = emins[0];outfar[1] = emins[1];outfar[2] = emaxs[2];break;
+       case 5: outnear[0] = emins[0];outnear[1] = emaxs[1];outnear[2] = emins[2];outfar[0] = emaxs[0];outfar[1] = emins[1];outfar[2] = emaxs[2];break;
+       case 6: outnear[0] = emaxs[0];outnear[1] = emins[1];outnear[2] = emins[2];outfar[0] = emins[0];outfar[1] = emaxs[1];outfar[2] = emaxs[2];break;
+       case 7: outnear[0] = emins[0];outnear[1] = emins[1];outnear[2] = emins[2];outfar[0] = emaxs[0];outfar[1] = emaxs[1];outfar[2] = emaxs[2];break;
+       }
+}
+
+void BoxPlaneCorners_Separate(const vec3_t emins, const vec3_t emaxs, const vec3_t normal, vec3_t outnear, vec3_t outfar)
+{
+       switch((normal[0] < 0) | ((normal[1] < 0) << 1) | ((normal[2] < 0) << 2))
+       {
+       default:
+       case 0: outnear[0] = emaxs[0];outnear[1] = emaxs[1];outnear[2] = emaxs[2];outfar[0] = emins[0];outfar[1] = emins[1];outfar[2] = emins[2];break;
+       case 1: outnear[0] = emins[0];outnear[1] = emaxs[1];outnear[2] = emaxs[2];outfar[0] = emaxs[0];outfar[1] = emins[1];outfar[2] = emins[2];break;
+       case 2: outnear[0] = emaxs[0];outnear[1] = emins[1];outnear[2] = emaxs[2];outfar[0] = emins[0];outfar[1] = emaxs[1];outfar[2] = emins[2];break;
+       case 3: outnear[0] = emins[0];outnear[1] = emins[1];outnear[2] = emaxs[2];outfar[0] = emaxs[0];outfar[1] = emaxs[1];outfar[2] = emins[2];break;
+       case 4: outnear[0] = emaxs[0];outnear[1] = emaxs[1];outnear[2] = emins[2];outfar[0] = emins[0];outfar[1] = emins[1];outfar[2] = emaxs[2];break;
+       case 5: outnear[0] = emins[0];outnear[1] = emaxs[1];outnear[2] = emins[2];outfar[0] = emaxs[0];outfar[1] = emins[1];outfar[2] = emaxs[2];break;
+       case 6: outnear[0] = emaxs[0];outnear[1] = emins[1];outnear[2] = emins[2];outfar[0] = emins[0];outfar[1] = emaxs[1];outfar[2] = emaxs[2];break;
+       case 7: outnear[0] = emins[0];outnear[1] = emins[1];outnear[2] = emins[2];outfar[0] = emaxs[0];outfar[1] = emaxs[1];outfar[2] = emaxs[2];break;
+       }
+}
+
+void BoxPlaneCornerDistances(const vec3_t emins, const vec3_t emaxs, const mplane_t *p, vec_t *outneardist, vec_t *outfardist)
+{
+       if (p->type < 3)
+       {
+               *outneardist = emins[p->type] - p->dist;
+               *outfardist = emaxs[p->type] - p->dist;
+               return;
+       }
+       switch(p->signbits)
+       {
+       default:
+       case 0: *outneardist = p->normal[0] * emaxs[0] + p->normal[1] * emaxs[1] + p->normal[2] * emaxs[2] - p->dist;*outfardist = p->normal[0] * emins[0] + p->normal[1] * emins[1] + p->normal[2] * emins[2] - p->dist;break;
+       case 1: *outneardist = p->normal[0] * emins[0] + p->normal[1] * emaxs[1] + p->normal[2] * emaxs[2] - p->dist;*outfardist = p->normal[0] * emaxs[0] + p->normal[1] * emins[1] + p->normal[2] * emins[2] - p->dist;break;
+       case 2: *outneardist = p->normal[0] * emaxs[0] + p->normal[1] * emins[1] + p->normal[2] * emaxs[2] - p->dist;*outfardist = p->normal[0] * emins[0] + p->normal[1] * emaxs[1] + p->normal[2] * emins[2] - p->dist;break;
+       case 3: *outneardist = p->normal[0] * emins[0] + p->normal[1] * emins[1] + p->normal[2] * emaxs[2] - p->dist;*outfardist = p->normal[0] * emaxs[0] + p->normal[1] * emaxs[1] + p->normal[2] * emins[2] - p->dist;break;
+       case 4: *outneardist = p->normal[0] * emaxs[0] + p->normal[1] * emaxs[1] + p->normal[2] * emins[2] - p->dist;*outfardist = p->normal[0] * emins[0] + p->normal[1] * emins[1] + p->normal[2] * emaxs[2] - p->dist;break;
+       case 5: *outneardist = p->normal[0] * emins[0] + p->normal[1] * emaxs[1] + p->normal[2] * emins[2] - p->dist;*outfardist = p->normal[0] * emaxs[0] + p->normal[1] * emins[1] + p->normal[2] * emaxs[2] - p->dist;break;
+       case 6: *outneardist = p->normal[0] * emaxs[0] + p->normal[1] * emins[1] + p->normal[2] * emins[2] - p->dist;*outfardist = p->normal[0] * emins[0] + p->normal[1] * emaxs[1] + p->normal[2] * emaxs[2] - p->dist;break;
+       case 7: *outneardist = p->normal[0] * emins[0] + p->normal[1] * emins[1] + p->normal[2] * emins[2] - p->dist;*outfardist = p->normal[0] * emaxs[0] + p->normal[1] * emaxs[1] + p->normal[2] * emaxs[2] - p->dist;break;
+       }
+}
+
+void BoxPlaneCornerDistances_Separate(const vec3_t emins, const vec3_t emaxs, const vec3_t normal, vec_t *outneardist, vec_t *outfardist)
+{
+       switch((normal[0] < 0) | ((normal[1] < 0) << 1) | ((normal[2] < 0) << 2))
+       {
+       default:
+       case 0: *outneardist = normal[0] * emaxs[0] + normal[1] * emaxs[1] + normal[2] * emaxs[2];*outfardist = normal[0] * emins[0] + normal[1] * emins[1] + normal[2] * emins[2];break;
+       case 1: *outneardist = normal[0] * emins[0] + normal[1] * emaxs[1] + normal[2] * emaxs[2];*outfardist = normal[0] * emaxs[0] + normal[1] * emins[1] + normal[2] * emins[2];break;
+       case 2: *outneardist = normal[0] * emaxs[0] + normal[1] * emins[1] + normal[2] * emaxs[2];*outfardist = normal[0] * emins[0] + normal[1] * emaxs[1] + normal[2] * emins[2];break;
+       case 3: *outneardist = normal[0] * emins[0] + normal[1] * emins[1] + normal[2] * emaxs[2];*outfardist = normal[0] * emaxs[0] + normal[1] * emaxs[1] + normal[2] * emins[2];break;
+       case 4: *outneardist = normal[0] * emaxs[0] + normal[1] * emaxs[1] + normal[2] * emins[2];*outfardist = normal[0] * emins[0] + normal[1] * emins[1] + normal[2] * emaxs[2];break;
+       case 5: *outneardist = normal[0] * emins[0] + normal[1] * emaxs[1] + normal[2] * emins[2];*outfardist = normal[0] * emaxs[0] + normal[1] * emins[1] + normal[2] * emaxs[2];break;
+       case 6: *outneardist = normal[0] * emaxs[0] + normal[1] * emins[1] + normal[2] * emins[2];*outfardist = normal[0] * emins[0] + normal[1] * emaxs[1] + normal[2] * emaxs[2];break;
+       case 7: *outneardist = normal[0] * emins[0] + normal[1] * emins[1] + normal[2] * emins[2];*outfardist = normal[0] * emaxs[0] + normal[1] * emaxs[1] + normal[2] * emaxs[2];break;
        }
 }
 
@@ -337,20 +428,38 @@ void AngleVectors (const vec3_t angles, vec3_t forward, vec3_t right, vec3_t up)
        }
        if (right || up)
        {
-               angle = angles[ROLL] * (M_PI*2 / 360);
-               sr = sin(angle);
-               cr = cos(angle);
-               if (right)
+               if (angles[ROLL])
                {
-                       right[0] = -1*(sr*sp*cy+cr*-sy);
-                       right[1] = -1*(sr*sp*sy+cr*cy);
-                       right[2] = -1*(sr*cp);
+                       angle = angles[ROLL] * (M_PI*2 / 360);
+                       sr = sin(angle);
+                       cr = cos(angle);
+                       if (right)
+                       {
+                               right[0] = -1*(sr*sp*cy+cr*-sy);
+                               right[1] = -1*(sr*sp*sy+cr*cy);
+                               right[2] = -1*(sr*cp);
+                       }
+                       if (up)
+                       {
+                               up[0] = (cr*sp*cy+-sr*-sy);
+                               up[1] = (cr*sp*sy+-sr*cy);
+                               up[2] = cr*cp;
+                       }
                }
-               if (up)
+               else
                {
-                       up[0] = (cr*sp*cy+-sr*-sy);
-                       up[1] = (cr*sp*sy+-sr*cy);
-                       up[2] = cr*cp;
+                       if (right)
+                       {
+                               right[0] = sy;
+                               right[1] = -cy;
+                               right[2] = 0;
+                       }
+                       if (up)
+                       {
+                               up[0] = (sp*cy);
+                               up[1] = (sp*sy);
+                               up[2] = cp;
+                       }
                }
        }
 }
@@ -373,22 +482,116 @@ void AngleVectorsFLU (const vec3_t angles, vec3_t forward, vec3_t left, vec3_t u
        }
        if (left || up)
        {
-               angle = angles[ROLL] * (M_PI*2 / 360);
-               sr = sin(angle);
-               cr = cos(angle);
-               if (left)
+               if (angles[ROLL])
+               {
+                       angle = angles[ROLL] * (M_PI*2 / 360);
+                       sr = sin(angle);
+                       cr = cos(angle);
+                       if (left)
+                       {
+                               left[0] = sr*sp*cy+cr*-sy;
+                               left[1] = sr*sp*sy+cr*cy;
+                               left[2] = sr*cp;
+                       }
+                       if (up)
+                       {
+                               up[0] = cr*sp*cy+-sr*-sy;
+                               up[1] = cr*sp*sy+-sr*cy;
+                               up[2] = cr*cp;
+                       }
+               }
+               else
+               {
+                       if (left)
+                       {
+                               left[0] = -sy;
+                               left[1] = cy;
+                               left[2] = 0;
+                       }
+                       if (up)
+                       {
+                               up[0] = sp*cy;
+                               up[1] = sp*sy;
+                               up[2] = cp;
+                       }
+               }
+       }
+}
+
+// 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)
                {
-                       left[0] = sr*sp*cy+cr*-sy;
-                       left[1] = sr*sp*sy+cr*cy;
-                       left[2] = sr*cp;
+                       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)
                {
-                       up[0] = cr*sp*cy+-sr*-sy;
-                       up[1] = cr*sp*sy+-sr*cy;
-                       up[2] = cr*cp;
+                       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
@@ -510,7 +713,7 @@ void Mathlib_Init(void)
 
 #include "matrixlib.h"
 
-void Matrix4x4_Print (const matrix4x4_t *in)
+void Matrix4x4_Print(const matrix4x4_t *in)
 {
        Con_Printf("%f %f %f %f\n%f %f %f %f\n%f %f %f %f\n%f %f %f %f\n"
        , in->m[0][0], in->m[0][1], in->m[0][2], in->m[0][3]
@@ -540,3 +743,16 @@ int Math_atov(const char *s, vec3_t out)
        return i;
 }
 
+void BoxFromPoints(vec3_t mins, vec3_t maxs, int numpoints, vec_t *point3f)
+{
+       int i;
+       VectorCopy(point3f, mins);
+       VectorCopy(point3f, maxs);
+       for (i = 1, point3f += 3;i < numpoints;i++, point3f += 3)
+       {
+               mins[0] = min(mins[0], point3f[0]);maxs[0] = max(maxs[0], point3f[0]);
+               mins[1] = min(mins[1], point3f[1]);maxs[1] = max(maxs[1], point3f[1]);
+               mins[2] = min(mins[2], point3f[2]);maxs[2] = max(maxs[2], point3f[2]);
+       }
+}
+