]> git.xonotic.org Git - xonotic/darkplaces.git/blobdiff - mathlib.c
Fix Q2BSP texture loading, Q2BSP contents issues, and add support for SURF_ALPHATEST...
[xonotic/darkplaces.git] / mathlib.c
index eaa1a765d8e05bc5c65328a808591ad5053941e1..738965a0491b5beb305f4cf7c6dc64189b11cacb 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];
 
@@ -29,87 +30,87 @@ float ixtable[4096];
 
 float m_bytenormals[NUMVERTEXNORMALS][3] =
 {
-{-0.525731, 0.000000, 0.850651}, {-0.442863, 0.238856, 0.864188},
-{-0.295242, 0.000000, 0.955423}, {-0.309017, 0.500000, 0.809017},
-{-0.162460, 0.262866, 0.951056}, {0.000000, 0.000000, 1.000000},
-{0.000000, 0.850651, 0.525731}, {-0.147621, 0.716567, 0.681718},
-{0.147621, 0.716567, 0.681718}, {0.000000, 0.525731, 0.850651},
-{0.309017, 0.500000, 0.809017}, {0.525731, 0.000000, 0.850651},
-{0.295242, 0.000000, 0.955423}, {0.442863, 0.238856, 0.864188},
-{0.162460, 0.262866, 0.951056}, {-0.681718, 0.147621, 0.716567},
-{-0.809017, 0.309017, 0.500000}, {-0.587785, 0.425325, 0.688191},
-{-0.850651, 0.525731, 0.000000}, {-0.864188, 0.442863, 0.238856},
-{-0.716567, 0.681718, 0.147621}, {-0.688191, 0.587785, 0.425325},
-{-0.500000, 0.809017, 0.309017}, {-0.238856, 0.864188, 0.442863},
-{-0.425325, 0.688191, 0.587785}, {-0.716567, 0.681718, -0.147621},
-{-0.500000, 0.809017, -0.309017}, {-0.525731, 0.850651, 0.000000},
-{0.000000, 0.850651, -0.525731}, {-0.238856, 0.864188, -0.442863},
-{0.000000, 0.955423, -0.295242}, {-0.262866, 0.951056, -0.162460},
-{0.000000, 1.000000, 0.000000}, {0.000000, 0.955423, 0.295242},
-{-0.262866, 0.951056, 0.162460}, {0.238856, 0.864188, 0.442863},
-{0.262866, 0.951056, 0.162460}, {0.500000, 0.809017, 0.309017},
-{0.238856, 0.864188, -0.442863}, {0.262866, 0.951056, -0.162460},
-{0.500000, 0.809017, -0.309017}, {0.850651, 0.525731, 0.000000},
-{0.716567, 0.681718, 0.147621}, {0.716567, 0.681718, -0.147621},
-{0.525731, 0.850651, 0.000000}, {0.425325, 0.688191, 0.587785},
-{0.864188, 0.442863, 0.238856}, {0.688191, 0.587785, 0.425325},
-{0.809017, 0.309017, 0.500000}, {0.681718, 0.147621, 0.716567},
-{0.587785, 0.425325, 0.688191}, {0.955423, 0.295242, 0.000000},
-{1.000000, 0.000000, 0.000000}, {0.951056, 0.162460, 0.262866},
-{0.850651, -0.525731, 0.000000}, {0.955423, -0.295242, 0.000000},
-{0.864188, -0.442863, 0.238856}, {0.951056, -0.162460, 0.262866},
-{0.809017, -0.309017, 0.500000}, {0.681718, -0.147621, 0.716567},
-{0.850651, 0.000000, 0.525731}, {0.864188, 0.442863, -0.238856},
-{0.809017, 0.309017, -0.500000}, {0.951056, 0.162460, -0.262866},
-{0.525731, 0.000000, -0.850651}, {0.681718, 0.147621, -0.716567},
-{0.681718, -0.147621, -0.716567}, {0.850651, 0.000000, -0.525731},
-{0.809017, -0.309017, -0.500000}, {0.864188, -0.442863, -0.238856},
-{0.951056, -0.162460, -0.262866}, {0.147621, 0.716567, -0.681718},
-{0.309017, 0.500000, -0.809017}, {0.425325, 0.688191, -0.587785},
-{0.442863, 0.238856, -0.864188}, {0.587785, 0.425325, -0.688191},
-{0.688191, 0.587785, -0.425325}, {-0.147621, 0.716567, -0.681718},
-{-0.309017, 0.500000, -0.809017}, {0.000000, 0.525731, -0.850651},
-{-0.525731, 0.000000, -0.850651}, {-0.442863, 0.238856, -0.864188},
-{-0.295242, 0.000000, -0.955423}, {-0.162460, 0.262866, -0.951056},
-{0.000000, 0.000000, -1.000000}, {0.295242, 0.000000, -0.955423},
-{0.162460, 0.262866, -0.951056}, {-0.442863, -0.238856, -0.864188},
-{-0.309017, -0.500000, -0.809017}, {-0.162460, -0.262866, -0.951056},
-{0.000000, -0.850651, -0.525731}, {-0.147621, -0.716567, -0.681718},
-{0.147621, -0.716567, -0.681718}, {0.000000, -0.525731, -0.850651},
-{0.309017, -0.500000, -0.809017}, {0.442863, -0.238856, -0.864188},
-{0.162460, -0.262866, -0.951056}, {0.238856, -0.864188, -0.442863},
-{0.500000, -0.809017, -0.309017}, {0.425325, -0.688191, -0.587785},
-{0.716567, -0.681718, -0.147621}, {0.688191, -0.587785, -0.425325},
-{0.587785, -0.425325, -0.688191}, {0.000000, -0.955423, -0.295242},
-{0.000000, -1.000000, 0.000000}, {0.262866, -0.951056, -0.162460},
-{0.000000, -0.850651, 0.525731}, {0.000000, -0.955423, 0.295242},
-{0.238856, -0.864188, 0.442863}, {0.262866, -0.951056, 0.162460},
-{0.500000, -0.809017, 0.309017}, {0.716567, -0.681718, 0.147621},
-{0.525731, -0.850651, 0.000000}, {-0.238856, -0.864188, -0.442863},
-{-0.500000, -0.809017, -0.309017}, {-0.262866, -0.951056, -0.162460},
-{-0.850651, -0.525731, 0.000000}, {-0.716567, -0.681718, -0.147621},
-{-0.716567, -0.681718, 0.147621}, {-0.525731, -0.850651, 0.000000},
-{-0.500000, -0.809017, 0.309017}, {-0.238856, -0.864188, 0.442863},
-{-0.262866, -0.951056, 0.162460}, {-0.864188, -0.442863, 0.238856},
-{-0.809017, -0.309017, 0.500000}, {-0.688191, -0.587785, 0.425325},
-{-0.681718, -0.147621, 0.716567}, {-0.442863, -0.238856, 0.864188},
-{-0.587785, -0.425325, 0.688191}, {-0.309017, -0.500000, 0.809017},
-{-0.147621, -0.716567, 0.681718}, {-0.425325, -0.688191, 0.587785},
-{-0.162460, -0.262866, 0.951056}, {0.442863, -0.238856, 0.864188},
-{0.162460, -0.262866, 0.951056}, {0.309017, -0.500000, 0.809017},
-{0.147621, -0.716567, 0.681718}, {0.000000, -0.525731, 0.850651},
-{0.425325, -0.688191, 0.587785}, {0.587785, -0.425325, 0.688191},
-{0.688191, -0.587785, 0.425325}, {-0.955423, 0.295242, 0.000000},
-{-0.951056, 0.162460, 0.262866}, {-1.000000, 0.000000, 0.000000},
-{-0.850651, 0.000000, 0.525731}, {-0.955423, -0.295242, 0.000000},
-{-0.951056, -0.162460, 0.262866}, {-0.864188, 0.442863, -0.238856},
-{-0.951056, 0.162460, -0.262866}, {-0.809017, 0.309017, -0.500000},
-{-0.864188, -0.442863, -0.238856}, {-0.951056, -0.162460, -0.262866},
-{-0.809017, -0.309017, -0.500000}, {-0.681718, 0.147621, -0.716567},
-{-0.681718, -0.147621, -0.716567}, {-0.850651, 0.000000, -0.525731},
-{-0.688191, 0.587785, -0.425325}, {-0.587785, 0.425325, -0.688191},
-{-0.425325, 0.688191, -0.587785}, {-0.425325, -0.688191, -0.587785},
-{-0.587785, -0.425325, -0.688191}, {-0.688191, -0.587785, -0.425325},
+{-0.525731f, 0.000000f, 0.850651f}, {-0.442863f, 0.238856f, 0.864188f},
+{-0.295242f, 0.000000f, 0.955423f}, {-0.309017f, 0.500000f, 0.809017f},
+{-0.162460f, 0.262866f, 0.951056f}, {0.000000f, 0.000000f, 1.000000f},
+{0.000000f, 0.850651f, 0.525731f}, {-0.147621f, 0.716567f, 0.681718f},
+{0.147621f, 0.716567f, 0.681718f}, {0.000000f, 0.525731f, 0.850651f},
+{0.309017f, 0.500000f, 0.809017f}, {0.525731f, 0.000000f, 0.850651f},
+{0.295242f, 0.000000f, 0.955423f}, {0.442863f, 0.238856f, 0.864188f},
+{0.162460f, 0.262866f, 0.951056f}, {-0.681718f, 0.147621f, 0.716567f},
+{-0.809017f, 0.309017f, 0.500000f}, {-0.587785f, 0.425325f, 0.688191f},
+{-0.850651f, 0.525731f, 0.000000f}, {-0.864188f, 0.442863f, 0.238856f},
+{-0.716567f, 0.681718f, 0.147621f}, {-0.688191f, 0.587785f, 0.425325f},
+{-0.500000f, 0.809017f, 0.309017f}, {-0.238856f, 0.864188f, 0.442863f},
+{-0.425325f, 0.688191f, 0.587785f}, {-0.716567f, 0.681718f, -0.147621f},
+{-0.500000f, 0.809017f, -0.309017f}, {-0.525731f, 0.850651f, 0.000000f},
+{0.000000f, 0.850651f, -0.525731f}, {-0.238856f, 0.864188f, -0.442863f},
+{0.000000f, 0.955423f, -0.295242f}, {-0.262866f, 0.951056f, -0.162460f},
+{0.000000f, 1.000000f, 0.000000f}, {0.000000f, 0.955423f, 0.295242f},
+{-0.262866f, 0.951056f, 0.162460f}, {0.238856f, 0.864188f, 0.442863f},
+{0.262866f, 0.951056f, 0.162460f}, {0.500000f, 0.809017f, 0.309017f},
+{0.238856f, 0.864188f, -0.442863f}, {0.262866f, 0.951056f, -0.162460f},
+{0.500000f, 0.809017f, -0.309017f}, {0.850651f, 0.525731f, 0.000000f},
+{0.716567f, 0.681718f, 0.147621f}, {0.716567f, 0.681718f, -0.147621f},
+{0.525731f, 0.850651f, 0.000000f}, {0.425325f, 0.688191f, 0.587785f},
+{0.864188f, 0.442863f, 0.238856f}, {0.688191f, 0.587785f, 0.425325f},
+{0.809017f, 0.309017f, 0.500000f}, {0.681718f, 0.147621f, 0.716567f},
+{0.587785f, 0.425325f, 0.688191f}, {0.955423f, 0.295242f, 0.000000f},
+{1.000000f, 0.000000f, 0.000000f}, {0.951056f, 0.162460f, 0.262866f},
+{0.850651f, -0.525731f, 0.000000f}, {0.955423f, -0.295242f, 0.000000f},
+{0.864188f, -0.442863f, 0.238856f}, {0.951056f, -0.162460f, 0.262866f},
+{0.809017f, -0.309017f, 0.500000f}, {0.681718f, -0.147621f, 0.716567f},
+{0.850651f, 0.000000f, 0.525731f}, {0.864188f, 0.442863f, -0.238856f},
+{0.809017f, 0.309017f, -0.500000f}, {0.951056f, 0.162460f, -0.262866f},
+{0.525731f, 0.000000f, -0.850651f}, {0.681718f, 0.147621f, -0.716567f},
+{0.681718f, -0.147621f, -0.716567f}, {0.850651f, 0.000000f, -0.525731f},
+{0.809017f, -0.309017f, -0.500000f}, {0.864188f, -0.442863f, -0.238856f},
+{0.951056f, -0.162460f, -0.262866f}, {0.147621f, 0.716567f, -0.681718f},
+{0.309017f, 0.500000f, -0.809017f}, {0.425325f, 0.688191f, -0.587785f},
+{0.442863f, 0.238856f, -0.864188f}, {0.587785f, 0.425325f, -0.688191f},
+{0.688191f, 0.587785f, -0.425325f}, {-0.147621f, 0.716567f, -0.681718f},
+{-0.309017f, 0.500000f, -0.809017f}, {0.000000f, 0.525731f, -0.850651f},
+{-0.525731f, 0.000000f, -0.850651f}, {-0.442863f, 0.238856f, -0.864188f},
+{-0.295242f, 0.000000f, -0.955423f}, {-0.162460f, 0.262866f, -0.951056f},
+{0.000000f, 0.000000f, -1.000000f}, {0.295242f, 0.000000f, -0.955423f},
+{0.162460f, 0.262866f, -0.951056f}, {-0.442863f, -0.238856f, -0.864188f},
+{-0.309017f, -0.500000f, -0.809017f}, {-0.162460f, -0.262866f, -0.951056f},
+{0.000000f, -0.850651f, -0.525731f}, {-0.147621f, -0.716567f, -0.681718f},
+{0.147621f, -0.716567f, -0.681718f}, {0.000000f, -0.525731f, -0.850651f},
+{0.309017f, -0.500000f, -0.809017f}, {0.442863f, -0.238856f, -0.864188f},
+{0.162460f, -0.262866f, -0.951056f}, {0.238856f, -0.864188f, -0.442863f},
+{0.500000f, -0.809017f, -0.309017f}, {0.425325f, -0.688191f, -0.587785f},
+{0.716567f, -0.681718f, -0.147621f}, {0.688191f, -0.587785f, -0.425325f},
+{0.587785f, -0.425325f, -0.688191f}, {0.000000f, -0.955423f, -0.295242f},
+{0.000000f, -1.000000f, 0.000000f}, {0.262866f, -0.951056f, -0.162460f},
+{0.000000f, -0.850651f, 0.525731f}, {0.000000f, -0.955423f, 0.295242f},
+{0.238856f, -0.864188f, 0.442863f}, {0.262866f, -0.951056f, 0.162460f},
+{0.500000f, -0.809017f, 0.309017f}, {0.716567f, -0.681718f, 0.147621f},
+{0.525731f, -0.850651f, 0.000000f}, {-0.238856f, -0.864188f, -0.442863f},
+{-0.500000f, -0.809017f, -0.309017f}, {-0.262866f, -0.951056f, -0.162460f},
+{-0.850651f, -0.525731f, 0.000000f}, {-0.716567f, -0.681718f, -0.147621f},
+{-0.716567f, -0.681718f, 0.147621f}, {-0.525731f, -0.850651f, 0.000000f},
+{-0.500000f, -0.809017f, 0.309017f}, {-0.238856f, -0.864188f, 0.442863f},
+{-0.262866f, -0.951056f, 0.162460f}, {-0.864188f, -0.442863f, 0.238856f},
+{-0.809017f, -0.309017f, 0.500000f}, {-0.688191f, -0.587785f, 0.425325f},
+{-0.681718f, -0.147621f, 0.716567f}, {-0.442863f, -0.238856f, 0.864188f},
+{-0.587785f, -0.425325f, 0.688191f}, {-0.309017f, -0.500000f, 0.809017f},
+{-0.147621f, -0.716567f, 0.681718f}, {-0.425325f, -0.688191f, 0.587785f},
+{-0.162460f, -0.262866f, 0.951056f}, {0.442863f, -0.238856f, 0.864188f},
+{0.162460f, -0.262866f, 0.951056f}, {0.309017f, -0.500000f, 0.809017f},
+{0.147621f, -0.716567f, 0.681718f}, {0.000000f, -0.525731f, 0.850651f},
+{0.425325f, -0.688191f, 0.587785f}, {0.587785f, -0.425325f, 0.688191f},
+{0.688191f, -0.587785f, 0.425325f}, {-0.955423f, 0.295242f, 0.000000f},
+{-0.951056f, 0.162460f, 0.262866f}, {-1.000000f, 0.000000f, 0.000000f},
+{-0.850651f, 0.000000f, 0.525731f}, {-0.955423f, -0.295242f, 0.000000f},
+{-0.951056f, -0.162460f, 0.262866f}, {-0.864188f, 0.442863f, -0.238856f},
+{-0.951056f, 0.162460f, -0.262866f}, {-0.809017f, 0.309017f, -0.500000f},
+{-0.864188f, -0.442863f, -0.238856f}, {-0.951056f, -0.162460f, -0.262866f},
+{-0.809017f, -0.309017f, -0.500000f}, {-0.681718f, 0.147621f, -0.716567f},
+{-0.681718f, -0.147621f, -0.716567f}, {-0.850651f, 0.000000f, -0.525731f},
+{-0.688191f, 0.587785f, -0.425325f}, {-0.587785f, 0.425325f, -0.688191f},
+{-0.425325f, 0.688191f, -0.587785f}, {-0.425325f, -0.688191f, -0.587785f},
+{-0.587785f, -0.425325f, -0.688191f}, {-0.688191f, -0.587785f, -0.425325f},
 };
 
 #if 0
@@ -197,30 +198,61 @@ void PerpendicularVector( vec3_t dst, const vec3_t src )
 // LordHavoc: like AngleVectors, but taking a forward vector instead of angles, useful!
 void VectorVectors(const vec3_t forward, vec3_t right, vec3_t up)
 {
-       float d;
-
-       right[0] = forward[2];
-       right[1] = -forward[0];
-       right[2] = forward[1];
-
-       d = DotProduct(forward, right);
-       VectorMA(right, -d, forward, right);
-       VectorNormalize(right);
-       CrossProduct(right, forward, up);
+       // NOTE: this is consistent to AngleVectors applied to AnglesFromVectors
+       if (forward[0] == 0 && forward[1] == 0)
+       {
+               if(forward[2] > 0)
+               {
+                       VectorSet(right, 0, -1, 0);
+                       VectorSet(up, -1, 0, 0);
+               }
+               else
+               {
+                       VectorSet(right, 0, -1, 0);
+                       VectorSet(up, 1, 0, 0);
+               }
+       }
+       else
+       {
+               right[0] = forward[1];
+               right[1] = -forward[0];
+               right[2] = 0;
+               VectorNormalize(right);
+
+               up[0] = (-forward[2]*forward[0]);
+               up[1] = (-forward[2]*forward[1]);
+               up[2] = (forward[0]*forward[0] + forward[1]*forward[1]);
+               VectorNormalize(up);
+       }
 }
 
 void VectorVectorsDouble(const double *forward, double *right, double *up)
 {
-       double d;
-
-       right[0] = forward[2];
-       right[1] = -forward[0];
-       right[2] = forward[1];
-
-       d = DotProduct(forward, right);
-       VectorMA(right, -d, forward, right);
-       VectorNormalize(right);
-       CrossProduct(right, forward, up);
+       if (forward[0] == 0 && forward[1] == 0)
+       {
+               if(forward[2] > 0)
+               {
+                       VectorSet(right, 0, -1, 0);
+                       VectorSet(up, -1, 0, 0);
+               }
+               else
+               {
+                       VectorSet(right, 0, -1, 0);
+                       VectorSet(up, 1, 0, 0);
+               }
+       }
+       else
+       {
+               right[0] = forward[1];
+               right[1] = -forward[0];
+               right[2] = 0;
+               VectorNormalize(right);
+
+               up[0] = (-forward[2]*forward[0]);
+               up[1] = (-forward[2]*forward[1]);
+               up[2] = (forward[0]*forward[0] + forward[1]*forward[1]);
+               VectorNormalize(up);
+       }
 }
 
 void RotatePointAroundVector( vec3_t dst, const vec3_t dir, const vec3_t point, float degrees )
@@ -517,6 +549,186 @@ void AngleVectorsFLU (const vec3_t angles, vec3_t forward, vec3_t left, vec3_t u
        }
 }
 
+void AngleVectorsDuke3DFLU (const vec3_t angles, vec3_t forward, vec3_t left, vec3_t up, double maxShearAngle)
+{
+       double angle, sr, sy, cr, cy;
+       double sxx, sxz, szx, szz;
+       double cosMaxShearAngle = cos(maxShearAngle * (M_PI*2 / 360));
+       double tanMaxShearAngle = tan(maxShearAngle * (M_PI*2 / 360));
+
+       angle = angles[YAW] * (M_PI*2 / 360);
+       sy = sin(angle);
+       cy = cos(angle);
+       angle = angles[PITCH] * (M_PI*2 / 360);
+
+       // We will calculate a shear matrix pitch = [[sxx sxz][szx szz]].
+
+       if (fabs(cos(angle)) > cosMaxShearAngle)
+       {
+               // Pure shear. Keep the original sign of the coefficients.
+               sxx = 1;
+               sxz = 0;
+               szx = -tan(angle);
+               szz = 1;
+               // Covering angle per screen coordinate:
+               // d/dt arctan((sxz + t*szz) / (sxx + t*szx)) @ t=0
+               // d_angle = det(S) / (sxx*sxx + szx*szx)
+               //         = 1 / (1 + tan^2 angle)
+               //         = cos^2 angle.
+       }
+       else
+       {
+               // A mix of shear and rotation. Implementation-wise, we're
+               // looking at a capsule, and making the screen surface
+               // tangential to it... and if we get here, we're looking at the
+               // two half-spheres of the capsule (and the cylinder part is
+               // handled above).
+               double x, y, h, t, d, f;
+               h = tanMaxShearAngle;
+               x = cos(angle);
+               y = sin(angle);
+               t = h * fabs(y) + sqrt(1 - (h * x) * (h * x));
+               sxx =  x * t;
+               sxz =  y * t - h * (y > 0 ? 1.0 : -1.0);
+               szx = -y * t;
+               szz =  x * t;
+               // BUT: keep the amount of a sphere we see in pitch direction
+               // invariant.
+               // Covering angle per screen coordinate:
+               // d_angle = det(S) / (sxx*sxx + szx*szx)
+               d = (sxx * szz - sxz * szx) / (sxx * sxx + szx * szx);
+               f = cosMaxShearAngle * cosMaxShearAngle / d;
+               sxz *= f;
+               szz *= f;
+       }
+
+       if (forward)
+       {
+               forward[0] = sxx*cy;
+               forward[1] = sxx*sy;
+               forward[2] = szx;
+       }
+       if (left || up)
+       {
+               if (angles[ROLL])
+               {
+                       angle = angles[ROLL] * (M_PI*2 / 360);
+                       sr = sin(angle);
+                       cr = cos(angle);
+                       if (left)
+                       {
+                               left[0] = sr*sxz*cy+cr*-sy;
+                               left[1] = sr*sxz*sy+cr*cy;
+                               left[2] = sr*szz;
+                       }
+                       if (up)
+                       {
+                               up[0] = cr*sxz*cy+-sr*-sy;
+                               up[1] = cr*sxz*sy+-sr*cy;
+                               up[2] = cr*szz;
+                       }
+               }
+               else
+               {
+                       if (left)
+                       {
+                               left[0] = -sy;
+                               left[1] = cy;
+                               left[2] = 0;
+                       }
+                       if (up)
+                       {
+                               up[0] = sxz*cy;
+                               up[1] = sxz*sy;
+                               up[2] = szz;
+                       }
+               }
+       }
+}
+
+// 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]));
+               // note: we know that angles[PITCH] is in ]-pi/2..pi/2[ due to atan2(anything, positive)
+               if (up)
+               {
+                       vec_t cp = cos(angles[PITCH]), sp = sin(angles[PITCH]);
+                       // note: we know cp > 0, due to the range angles[pitch] is in
+                       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));
+                       // for up == '0 0 1', this is
+                       // angles[ROLL] = -atan2(0, cp);
+                       // which is 0
+               }
+               else
+                       angles[ROLL] = 0;
+
+               // so no up vector is equivalent to '1 0 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])
 {
@@ -645,7 +857,7 @@ void Matrix4x4_Print(const matrix4x4_t *in)
        , in->m[3][0], in->m[3][1], in->m[3][2], in->m[3][3]);
 }
 
-int Math_atov(const char *s, vec3_t out)
+int Math_atov(const char *s, prvm_vec3_t out)
 {
        int i;
        VectorClear(out);
@@ -679,3 +891,12 @@ 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;
+}
+