dlls/d3drm/math.c

   1 /*
   2  * Copyright 2007 David Adam
   3  * Copyright 2007 Vijay Kiran Kamuju
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2.1 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  18  */
  19
  20 #define NONAMELESSUNION
  21
  22 #include <math.h>
  23 #include <stdarg.h>
  24 #include "windef.h"
  25 #include "winbase.h"
  26 #include "wingdi.h"
  27 #include "d3drmdef.h"
  28
  29 /* Create a RGB color from its components */
  30 D3DCOLOR WINAPI D3DRMCreateColorRGB(D3DVALUE red, D3DVALUE green, D3DVALUE blue)
  31 {
  32     return (D3DRMCreateColorRGBA(red, green, blue, 255.0));
  33 }
  34 /* Create a RGBA color from its components */
  35 D3DCOLOR WINAPI D3DRMCreateColorRGBA(D3DVALUE red, D3DVALUE green, D3DVALUE blue, D3DVALUE alpha)
  36 {
  37     int Red, Green, Blue, Alpha;
  38     Red=floor(red*255);
  39     Green=floor(green*255);
  40     Blue=floor(blue*255);
  41     Alpha=floor(alpha*255);
  42     if (red < 0) Red=0;
  43     if (red > 1) Red=255;
  44     if (green < 0) Green=0;
  45     if (green > 1) Green=255;
  46     if (blue < 0) Blue=0;
  47     if (blue > 1) Blue=255;
  48     if (alpha < 0) Alpha=0;
  49     if (alpha > 1) Alpha=255;
  50     return (RGBA_MAKE(Red, Green, Blue, Alpha));
  51 }
  52
  53 /* Determine the alpha part of a color */
  54 D3DVALUE WINAPI D3DRMColorGetAlpha(D3DCOLOR color)
  55 {
  56     return (RGBA_GETALPHA(color)/255.0);
  57 }
  58
  59 /* Determine the blue part of a color */
  60 D3DVALUE WINAPI D3DRMColorGetBlue(D3DCOLOR color)
  61 {
  62     return (RGBA_GETBLUE(color)/255.0);
  63 }
  64
  65 /* Determine the green part of a color */
  66 D3DVALUE WINAPI D3DRMColorGetGreen(D3DCOLOR color)
  67 {
  68     return (RGBA_GETGREEN(color)/255.0);
  69 }
  70
  71 /* Determine the red part of a color */
  72 D3DVALUE WINAPI D3DRMColorGetRed(D3DCOLOR color)
  73 {
  74     return (RGBA_GETRED(color)/255.0);
  75 }
  76
  77 /* Product of 2 quaternions */
  78 D3DRMQUATERNION * WINAPI D3DRMQuaternionMultiply(D3DRMQUATERNION *q, D3DRMQUATERNION *a, D3DRMQUATERNION *b)
  79 {
  80     D3DRMQUATERNION temp;
  81     D3DVECTOR cross_product;
  82
  83     D3DRMVectorCrossProduct(&cross_product, &a->v, &b->v);
  84     temp.s = a->s * b->s - D3DRMVectorDotProduct(&a->v, &b->v);
  85     temp.v.u1.x = a->s * b->v.u1.x + b->s * a->v.u1.x + cross_product.u1.x;
  86     temp.v.u2.y = a->s * b->v.u2.y + b->s * a->v.u2.y + cross_product.u2.y;
  87     temp.v.u3.z = a->s * b->v.u3.z + b->s * a->v.u3.z + cross_product.u3.z;
  88
  89     *q = temp;
  90     return q;
  91 }
  92
  93 /* Matrix for the Rotation that a unit quaternion represents */
  94 void WINAPI D3DRMMatrixFromQuaternion(D3DRMMATRIX4D m, D3DRMQUATERNION *q)
  95 {
  96     D3DVALUE w,x,y,z;
  97     w = q->s;
  98     x = q->v.u1.x;
  99     y = q->v.u2.y;
 100     z = q->v.u3.z;
 101     m[0][0] = 1.0-2.0*(y*y+z*z);
 102     m[1][1] = 1.0-2.0*(x*x+z*z);
 103     m[2][2] = 1.0-2.0*(x*x+y*y);
 104     m[1][0] = 2.0*(x*y+z*w);
 105     m[0][1] = 2.0*(x*y-z*w);
 106     m[2][0] = 2.0*(x*z-y*w);
 107     m[0][2] = 2.0*(x*z+y*w);
 108     m[2][1] = 2.0*(y*z+x*w);
 109     m[1][2] = 2.0*(y*z-x*w);
 110     m[3][0] = 0.0;
 111     m[3][1] = 0.0;
 112     m[3][2] = 0.0;
 113     m[0][3] = 0.0;
 114     m[1][3] = 0.0;
 115     m[2][3] = 0.0;
 116     m[3][3] = 1.0;
 117 }
 118
 119 /* Return a unit quaternion that represents a rotation of an angle around an axis */
 120 D3DRMQUATERNION * WINAPI D3DRMQuaternionFromRotation(D3DRMQUATERNION *q, D3DVECTOR *v, D3DVALUE theta)
 121 {
 122     q->s = cos(theta/2.0);
 123     D3DRMVectorScale(&q->v, D3DRMVectorNormalize(v), sin(theta/2.0));
 124     return q;
 125 }
 126
 127 /* Interpolation between two quaternions */
 128 D3DRMQUATERNION * WINAPI D3DRMQuaternionSlerp(D3DRMQUATERNION *q,
 129         D3DRMQUATERNION *a, D3DRMQUATERNION *b, D3DVALUE alpha)
 130 {
 131     D3DVALUE dot, epsilon, temp, theta, u;
 132     D3DVECTOR v1, v2;
 133
 134     dot = a->s * b->s + D3DRMVectorDotProduct(&a->v, &b->v);
 135     epsilon = 1.0f;
 136     temp = 1.0f - alpha;
 137     u = alpha;
 138     if (dot < 0.0)
 139     {
 140      epsilon = -1.0;
 141      dot = -dot;
 142     }
 143     if( 1.0f - dot > 0.001f )
 144     {
 145         theta = acos(dot);
 146         temp  = sin(theta * temp) / sin(theta);
 147         u = sin(theta * alpha) / sin(theta);
 148     }
 149     q->s = temp * a->s + epsilon * u * b->s;
 150     D3DRMVectorScale(&v1, &a->v, temp);
 151     D3DRMVectorScale(&v2, &b->v, epsilon * u);
 152     D3DRMVectorAdd(&q->v, &v1, &v2);
 153     return q;
 154 }
 155
 156 /* Add Two Vectors */
 157 D3DVECTOR * WINAPI D3DRMVectorAdd(D3DVECTOR *d, D3DVECTOR *s1, D3DVECTOR *s2)
 158 {
 159     D3DVECTOR temp;
 160
 161     temp.u1.x=s1->u1.x + s2->u1.x;
 162     temp.u2.y=s1->u2.y + s2->u2.y;
 163     temp.u3.z=s1->u3.z + s2->u3.z;
 164
 165     *d = temp;
 166     return d;
 167 }
 168
 169 /* Subtract Two Vectors */
 170 D3DVECTOR * WINAPI D3DRMVectorSubtract(D3DVECTOR *d, D3DVECTOR *s1, D3DVECTOR *s2)
 171 {
 172     D3DVECTOR temp;
 173
 174     temp.u1.x=s1->u1.x - s2->u1.x;
 175     temp.u2.y=s1->u2.y - s2->u2.y;
 176     temp.u3.z=s1->u3.z - s2->u3.z;
 177
 178     *d = temp;
 179     return d;
 180 }
 181
 182 /* Cross Product of Two Vectors */
 183 D3DVECTOR * WINAPI D3DRMVectorCrossProduct(D3DVECTOR *d, D3DVECTOR *s1, D3DVECTOR *s2)
 184 {
 185     D3DVECTOR temp;
 186
 187     temp.u1.x=s1->u2.y * s2->u3.z - s1->u3.z * s2->u2.y;
 188     temp.u2.y=s1->u3.z * s2->u1.x - s1->u1.x * s2->u3.z;
 189     temp.u3.z=s1->u1.x * s2->u2.y - s1->u2.y * s2->u1.x;
 190
 191     *d = temp;
 192     return d;
 193 }
 194
 195 /* Dot Product of Two vectors */
 196 D3DVALUE WINAPI D3DRMVectorDotProduct(D3DVECTOR *s1, D3DVECTOR *s2)
 197 {
 198     D3DVALUE dot_product;
 199     dot_product=s1->u1.x * s2->u1.x + s1->u2.y * s2->u2.y + s1->u3.z * s2->u3.z;
 200     return dot_product;
 201 }
 202
 203 /* Norm of a vector */
 204 D3DVALUE WINAPI D3DRMVectorModulus(D3DVECTOR *v)
 205 {
 206     D3DVALUE result;
 207     result=sqrt(v->u1.x * v->u1.x + v->u2.y * v->u2.y + v->u3.z * v->u3.z);
 208     return result;
 209 }
 210
 211 /* Normalize a vector.  Returns (1,0,0) if INPUT is the NULL vector. */
 212 D3DVECTOR * WINAPI D3DRMVectorNormalize(D3DVECTOR *u)
 213 {
 214     D3DVALUE modulus = D3DRMVectorModulus(u);
 215     if(modulus)
 216     {
 217         D3DRMVectorScale(u,u,1.0/modulus);
 218     }
 219     else
 220     {
 221         u->u1.x=1.0;
 222         u->u2.y=0.0;
 223         u->u3.z=0.0;
 224     }
 225     return u;
 226 }
 227
 228 /* Returns a random unit vector */
 229 D3DVECTOR * WINAPI D3DRMVectorRandom(D3DVECTOR *d)
 230 {
 231     d->u1.x = rand();
 232     d->u2.y = rand();
 233     d->u3.z = rand();
 234     D3DRMVectorNormalize(d);
 235     return d;
 236 }
 237
 238 /* Reflection of a vector on a surface */
 239 D3DVECTOR * WINAPI D3DRMVectorReflect(D3DVECTOR *r, D3DVECTOR *ray, D3DVECTOR *norm)
 240 {
 241     D3DVECTOR sca, temp;
 242     D3DRMVectorSubtract(&temp, D3DRMVectorScale(&sca, norm, 2.0*D3DRMVectorDotProduct(ray,norm)), ray);
 243
 244     *r = temp;
 245     return r;
 246 }
 247
 248 /* Rotation of a vector */
 249 D3DVECTOR * WINAPI D3DRMVectorRotate(D3DVECTOR *r, D3DVECTOR *v, D3DVECTOR *axis, D3DVALUE theta)
 250 {
 251     D3DRMQUATERNION quaternion1, quaternion2, quaternion3;
 252     D3DVECTOR norm;
 253
 254     quaternion1.s = cos(theta * 0.5f);
 255     quaternion2.s = cos(theta * 0.5f);
 256     norm = *D3DRMVectorNormalize(axis);
 257     D3DRMVectorScale(&quaternion1.v, &norm, sin(theta * 0.5f));
 258     D3DRMVectorScale(&quaternion2.v, &norm, -sin(theta * 0.5f));
 259     quaternion3.s = 0.0;
 260     quaternion3.v = *v;
 261     D3DRMQuaternionMultiply(&quaternion1, &quaternion1, &quaternion3);
 262     D3DRMQuaternionMultiply(&quaternion1, &quaternion1, &quaternion2);
 263
 264     *r = *D3DRMVectorNormalize(&quaternion1.v);
 265     return r;
 266 }
 267
 268 /* Scale a vector */
 269 D3DVECTOR * WINAPI D3DRMVectorScale(D3DVECTOR *d, D3DVECTOR *s, D3DVALUE factor)
 270 {
 271     D3DVECTOR temp;
 272
 273     temp.u1.x=factor * s->u1.x;
 274     temp.u2.y=factor * s->u2.y;
 275     temp.u3.z=factor * s->u3.z;
 276
 277     *d = temp;
 278     return d;
 279 }