diff options
Diffstat (limited to 'mesalib/progs/util/trackball.c')
| -rw-r--r-- | mesalib/progs/util/trackball.c | 338 |
1 files changed, 0 insertions, 338 deletions
diff --git a/mesalib/progs/util/trackball.c b/mesalib/progs/util/trackball.c deleted file mode 100644 index a6c4c60d0..000000000 --- a/mesalib/progs/util/trackball.c +++ /dev/null @@ -1,338 +0,0 @@ -#include <stdio.h> -/* - * (c) Copyright 1993, 1994, Silicon Graphics, Inc. - * ALL RIGHTS RESERVED - * Permission to use, copy, modify, and distribute this software for - * any purpose and without fee is hereby granted, provided that the above - * copyright notice appear in all copies and that both the copyright notice - * and this permission notice appear in supporting documentation, and that - * the name of Silicon Graphics, Inc. not be used in advertising - * or publicity pertaining to distribution of the software without specific, - * written prior permission. - * - * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS" - * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE, - * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR - * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON - * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT, - * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY - * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION, - * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF - * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN - * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON - * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE - * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE. - * - * US Government Users Restricted Rights - * Use, duplication, or disclosure by the Government is subject to - * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph - * (c)(1)(ii) of the Rights in Technical Data and Computer Software - * clause at DFARS 252.227-7013 and/or in similar or successor - * clauses in the FAR or the DOD or NASA FAR Supplement. - * Unpublished-- rights reserved under the copyright laws of the - * United States. Contractor/manufacturer is Silicon Graphics, - * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311. - * - * OpenGL(TM) is a trademark of Silicon Graphics, Inc. - */ -/* - * Trackball code: - * - * Implementation of a virtual trackball. - * Implemented by Gavin Bell, lots of ideas from Thant Tessman and - * the August '88 issue of Siggraph's "Computer Graphics," pp. 121-129. - * - * Vector manip code: - * - * Original code from: - * David M. Ciemiewicz, Mark Grossman, Henry Moreton, and Paul Haeberli - * - * Much mucking with by: - * Gavin Bell - */ -#if defined(_WIN32) -#pragma warning (disable:4244) /* disable bogus conversion warnings */ -#endif -#include <math.h> -#include "trackball.h" - -/* - * This size should really be based on the distance from the center of - * rotation to the point on the object underneath the mouse. That - * point would then track the mouse as closely as possible. This is a - * simple example, though, so that is left as an Exercise for the - * Programmer. - */ -#define TRACKBALLSIZE (0.8f) - -/* - * Local function prototypes (not defined in trackball.h) - */ -static float tb_project_to_sphere(float, float, float); -static void normalize_quat(float [4]); - -static void -vzero(float v[3]) -{ - v[0] = 0.0; - v[1] = 0.0; - v[2] = 0.0; -} - -static void -vset(float v[3], float x, float y, float z) -{ - v[0] = x; - v[1] = y; - v[2] = z; -} - -static void -vsub(const float src1[3], const float src2[3], float dst[3]) -{ - dst[0] = src1[0] - src2[0]; - dst[1] = src1[1] - src2[1]; - dst[2] = src1[2] - src2[2]; -} - -static void -vcopy(const float v1[3], float v2[3]) -{ - register int i; - for (i = 0 ; i < 3 ; i++) - v2[i] = v1[i]; -} - -static void -vcross(const float v1[3], const float v2[3], float cross[3]) -{ - float temp[3]; - - temp[0] = (v1[1] * v2[2]) - (v1[2] * v2[1]); - temp[1] = (v1[2] * v2[0]) - (v1[0] * v2[2]); - temp[2] = (v1[0] * v2[1]) - (v1[1] * v2[0]); - vcopy(temp, cross); -} - -static float -vlength(const float v[3]) -{ - return sqrt(v[0] * v[0] + v[1] * v[1] + v[2] * v[2]); -} - -static void -vscale(float v[3], float div) -{ - v[0] *= div; - v[1] *= div; - v[2] *= div; -} - -static void -vnormal(float v[3]) -{ - vscale(v,1.0/vlength(v)); -} - -static float -vdot(const float v1[3], const float v2[3]) -{ - return v1[0]*v2[0] + v1[1]*v2[1] + v1[2]*v2[2]; -} - -static void -vadd(const float src1[3], const float src2[3], float dst[3]) -{ - dst[0] = src1[0] + src2[0]; - dst[1] = src1[1] + src2[1]; - dst[2] = src1[2] + src2[2]; -} - -/* - * Ok, simulate a track-ball. Project the points onto the virtual - * trackball, then figure out the axis of rotation, which is the cross - * product of P1 P2 and O P1 (O is the center of the ball, 0,0,0) - * Note: This is a deformed trackball-- is a trackball in the center, - * but is deformed into a hyperbolic sheet of rotation away from the - * center. This particular function was chosen after trying out - * several variations. - * - * It is assumed that the arguments to this routine are in the range - * (-1.0 ... 1.0) - */ -void -trackball(float q[4], float p1x, float p1y, float p2x, float p2y) -{ - float a[3]; /* Axis of rotation */ - float phi; /* how much to rotate about axis */ - float p1[3], p2[3], d[3]; - float t; - - if (p1x == p2x && p1y == p2y) { - /* Zero rotation */ - vzero(q); - q[3] = 1.0; - return; - } - - /* - * First, figure out z-coordinates for projection of P1 and P2 to - * deformed sphere - */ - vset(p1,p1x,p1y,tb_project_to_sphere(TRACKBALLSIZE,p1x,p1y)); - vset(p2,p2x,p2y,tb_project_to_sphere(TRACKBALLSIZE,p2x,p2y)); - - /* - * Now, we want the cross product of P1 and P2 - */ - vcross(p2,p1,a); - - /* - * Figure out how much to rotate around that axis. - */ - vsub(p1,p2,d); - t = vlength(d) / (2.0*TRACKBALLSIZE); - - /* - * Avoid problems with out-of-control values... - */ - if (t > 1.0) t = 1.0; - if (t < -1.0) t = -1.0; - phi = 2.0 * asin(t); - - axis_to_quat(a,phi,q); -} - -/* - * Given an axis and angle, compute quaternion. - */ -void -axis_to_quat(const float a[3], float phi, float q[4]) -{ - vcopy(a,q); - vnormal(q); - vscale(q, sin(phi/2.0)); - q[3] = cos(phi/2.0); -} - -/* - * Project an x,y pair onto a sphere of radius r OR a hyperbolic sheet - * if we are away from the center of the sphere. - */ -static float -tb_project_to_sphere(float r, float x, float y) -{ - float d, t, z; - - d = sqrt(x*x + y*y); - if (d < r * 0.70710678118654752440) { /* Inside sphere */ - z = sqrt(r*r - d*d); - } else { /* On hyperbola */ - t = r / 1.41421356237309504880; - z = t*t / d; - } - return z; -} - -/* - * Given two rotations, e1 and e2, expressed as quaternion rotations, - * figure out the equivalent single rotation and stuff it into dest. - * - * This routine also normalizes the result every RENORMCOUNT times it is - * called, to keep error from creeping in. - * - * NOTE: This routine is written so that q1 or q2 may be the same - * as dest (or each other). - */ - -#define RENORMCOUNT 97 - -void -add_quats(const float q1[4], const float q2[4], float dest[4]) -{ - static int count=0; - float t1[4], t2[4], t3[4]; - float tf[4]; - -#if 0 -printf("q1 = %f %f %f %f\n", q1[0], q1[1], q1[2], q1[3]); -printf("q2 = %f %f %f %f\n", q2[0], q2[1], q2[2], q2[3]); -#endif - - vcopy(q1,t1); - vscale(t1,q2[3]); - - vcopy(q2,t2); - vscale(t2,q1[3]); - - vcross(q2,q1,t3); - vadd(t1,t2,tf); - vadd(t3,tf,tf); - tf[3] = q1[3] * q2[3] - vdot(q1,q2); - -#if 0 -printf("tf = %f %f %f %f\n", tf[0], tf[1], tf[2], tf[3]); -#endif - - dest[0] = tf[0]; - dest[1] = tf[1]; - dest[2] = tf[2]; - dest[3] = tf[3]; - - if (++count > RENORMCOUNT) { - count = 0; - normalize_quat(dest); - } -} - -/* - * Quaternions always obey: a^2 + b^2 + c^2 + d^2 = 1.0 - * If they don't add up to 1.0, dividing by their magnitued will - * renormalize them. - * - * Note: See the following for more information on quaternions: - * - * - Shoemake, K., Animating rotation with quaternion curves, Computer - * Graphics 19, No 3 (Proc. SIGGRAPH'85), 245-254, 1985. - * - Pletinckx, D., Quaternion calculus as a basic tool in computer - * graphics, The Visual Computer 5, 2-13, 1989. - */ -static void -normalize_quat(float q[4]) -{ - int i; - float mag; - - mag = sqrt(q[0]*q[0] + q[1]*q[1] + q[2]*q[2] + q[3]*q[3]); - for (i = 0; i < 4; i++) - q[i] /= mag; -} - -/* - * Build a rotation matrix, given a quaternion rotation. - * - */ -void -build_rotmatrix(float m[4][4], const float q[4]) -{ - m[0][0] = 1.0 - 2.0 * (q[1] * q[1] + q[2] * q[2]); - m[0][1] = 2.0 * (q[0] * q[1] - q[2] * q[3]); - m[0][2] = 2.0 * (q[2] * q[0] + q[1] * q[3]); - m[0][3] = 0.0; - - m[1][0] = 2.0 * (q[0] * q[1] + q[2] * q[3]); - m[1][1]= 1.0 - 2.0 * (q[2] * q[2] + q[0] * q[0]); - m[1][2] = 2.0 * (q[1] * q[2] - q[0] * q[3]); - m[1][3] = 0.0; - - m[2][0] = 2.0 * (q[2] * q[0] - q[1] * q[3]); - m[2][1] = 2.0 * (q[1] * q[2] + q[0] * q[3]); - m[2][2] = 1.0 - 2.0 * (q[1] * q[1] + q[0] * q[0]); - m[2][3] = 0.0; - - m[3][0] = 0.0; - m[3][1] = 0.0; - m[3][2] = 0.0; - m[3][3] = 1.0; -} - |