54 flt VDot(vector *a, vector *b) {  in VDot()  argument
55     return (a->x * b->x + a->y * b->y + a->z * b->z);  in VDot()
58 void VCross(vector *a, vector *b, vector *c) {  in VCross()  argument
59     c->x = (a->y * b->z) - (a->z * b->y);  in VCross()
60     c->y = (a->z * b->x) - (a->x * b->z);  in VCross()
61     c->z = (a->x * b->y) - (a->y * b->x);  in VCross()
64 flt VLength(vector *a) {  in VLength()  argument
65     return (flt)sqrt((a->x * a->x) + (a->y * a->y) + (a->z * a->z));  in VLength()
68 void VNorm(vector *a) {  in VNorm()  argument
71     len = sqrt((a->x * a->x) + (a->y * a->y) + (a->z * a->z));  in VNorm()
73         a->x /= len;  in VNorm()
74         a->y /= len;  in VNorm()
75         a->z /= len;  in VNorm()
79 void VAdd(vector *a, vector *b, vector *c) {  in VAdd()  argument
80     c->x = (a->x + b->x);  in VAdd()
81     c->y = (a->y + b->y);  in VAdd()
82     c->z = (a->z + b->z);  in VAdd()
85 void VSub(vector *a, vector *b, vector *c) {  in VSub()  argument
86     c->x = (a->x - b->x);  in VSub()
87     c->y = (a->y - b->y);  in VSub()
88     c->z = (a->z - b->z);  in VSub()
91 void VAddS(flt a, vector *A, vector *B, vector *C) {  in VAddS()  argument
92     C->x = (a * A->x) + B->x;  in VAddS()
93     C->y = (a * A->y) + B->y;  in VAddS()
94     C->z = (a * A->z) + B->z;  in VAddS()
97 vector Raypnt(ray *a, flt t) {  in Raypnt()  argument
100     temp.x = a->o.x + (a->d.x * t);  in Raypnt()
101     temp.y = a->o.y + (a->d.y * t);  in Raypnt()
102     temp.z = a->o.z + (a->d.z * t);  in Raypnt()
107 void VScale(vector *a, flt s) {  in VScale()  argument
108     a->x *= s;  in VScale()
109     a->y *= s;  in VScale()
110     a->z *= s;  in VScale()
113 void ColorAddS(color *a, color *b, flt s) {  in ColorAddS()  argument
114     a->r += b->r * s;  in ColorAddS()
115     a->g += b->g * s;  in ColorAddS()
116     a->b += b->b * s;  in ColorAddS()
119 void ColorAccum(color *a, color *b) {  in ColorAccum()  argument
120     a->r += b->r;  in ColorAccum()
121     a->g += b->g;  in ColorAccum()
122     a->b += b->b;  in ColorAccum()
125 void ColorScale(color *a, flt s) {  in ColorScale()  argument
126     a->r *= s;  in ColorScale()
127     a->g *= s;  in ColorScale()
128     a->b *= s;  in ColorScale()