1 /* -*- Mode: C; tab-width: 4 -*- */
2 /* atunnels --- OpenGL Advanced Tunnel Demo */
4 #if !defined( lint ) && !defined( SABER )
5 static const char sccsid[] = "@(#)tunnel_draw.c 5.02 2002/03/16 xlockmore";
8 /* Copyright (c) E. Lassauge, 2002. */
11 * Permission to use, copy, modify, and distribute this software and its
12 * documentation for any purpose and without fee is hereby granted,
13 * provided that the above copyright notice appear in all copies and that
14 * both that copyright notice and this permission notice appear in
15 * supporting documentation.
17 * This file is provided AS IS with no warranties of any kind. The author
18 * shall have no liability with respect to the infringement of copyrights,
19 * trade secrets or any patents by this file or any part thereof. In no
20 * event will the author be liable for any lost revenue or profits or
21 * other special, indirect and consequential damages.
23 * The original code for this mode was written by Roman Podobedov
25 * WEB: http://romka.demonews.com
27 * Eric Lassauge (March-16-2002) <lassauge@mail.dotcom.fr>
28 * http://lassauge.free.fr/linux.html
38 #ifdef USE_GL /* whole file */
47 #include "tunnel_draw.h"
51 float x, y, z; /* Point coordinates */
54 typedef struct _tnPath
63 const cvPoint initpath[]={
64 {0.000000, 0.000000, 0.000000},
65 {2.000000, 1.000000, 0.000000},
66 {4.000000, 0.000000, 0.000000},
67 {6.000000, 1.000000, 0.000000},
68 {8.000000, 0.000000, 1.000000},
69 {10.000000, 1.000000, 1.000000},
70 {12.000000, 1.500000, 0.000000},
71 {14.000000, 0.000000, 0.000000},
72 {16.000000, 1.000000, 0.000000},
73 {18.000000, 0.000000, 0.000000},
74 {20.000000, 0.000000, 1.000000},
75 {22.000000, 1.000000, 0.000000},
76 {24.000000, 0.000000, 1.000000},
77 {26.000000, 0.000000, 1.000000},
78 {28.000000, 1.000000, 0.000000},
79 {30.000000, 0.000000, 2.000000},
80 {32.000000, 1.000000, 0.000000},
81 {34.000000, 0.000000, 2.000000},
82 {-1.000000, -1.000000, -1.000000}
85 /* Camera variables */
87 static tnPath *cam_pos;
90 /* Tunnel Drawing Variables */
92 static cvPoint prev_points[10];
93 static int current_texture;
97 static int ModeXFlag=0;
99 /*=================== Vector normalization ==================================*/
100 void normalize(cvPoint *V)
105 d = (float)sqrt(V->x*V->x + V->y*V->y + V->z*V->z);
112 /*=================== C = A x B (Vector multiply) ==========================*/
113 void vect_mult(cvPoint *A, cvPoint *B, cvPoint *C)
115 /* Vector multiply */
116 C->x = A->y*B->z - A->z*B->y;
117 C->y = A->z*B->x - A->x*B->z;
118 C->z = A->x*B->y - A->y*B->x;
121 /* Catmull-Rom Curve calculations */
122 void cvCatmullRom(cvPoint *p, float t, cvPoint *outp)
130 outp->x = (-t*t1*p[0].x + (2-5*t2+3*t3)*p[1].x + t*(1+4*t-3*t2)*p[2].x - t2*(1-t)*p[3].x)/2;
131 outp->y = (-t*t1*p[0].y + (2-5*t2+3*t3)*p[1].y + t*(1+4*t-3*t2)*p[2].y - t2*(1-t)*p[3].y)/2;
132 outp->z = (-t*t1*p[0].z + (2-5*t2+3*t3)*p[1].z + t*(1+4*t-3*t2)*p[2].z - t2*(1-t)*p[3].z)/2;
135 /*=================== Point Rotating Around Line ===========================
136 // p - original point
138 // pl - pivot line (vector)
139 // a - angle to rotate in radians
140 // outp - output point
141 //==========================================================================
143 void RotateAroundLine(cvPoint *p, cvPoint *pp, cvPoint *pl, float a, cvPoint *outp)
146 float l, m, n, ca, sa;
159 p2.x = p1.x*((l*l)+ca*(1-l*l)) + p1.y*(l*(1-ca)*m+n*sa) + p1.z*(l*(1-ca)*n-m*sa);
160 p2.y = p1.x*(l*(1-ca)*m-n*sa) + p1.y*(m*m+ca*(1-m*m)) + p1.z*(m*(1-ca)*n+l*sa);
161 p2.z = p1.x*(l*(1-ca)*n+m*sa) + p1.y*(m*(1-ca)*n-l*sa) + p1.z*(n*n+ca*(1-n*n));
163 outp->x = p2.x + pp->x;
164 outp->y = p2.y + pp->y;
165 outp->z = p2.z + pp->z;
169 /*=================== Load camera and tunnel path ==========================*/
170 static void LoadPath(void)
173 tnPath *path1=NULL, *path2=NULL;
175 cvPoint *f = (cvPoint *)initpath;
186 path = (tnPath *)malloc(sizeof(tnPath));
191 path2 = (tnPath *)malloc(sizeof(tnPath));
206 /*=================== Tunnel Initialization ================================*/
207 void InitTunnel(void)
213 void DrawTunnel(int do_texture, int do_light, GLuint *textures)
215 tnPath *p, *p1, *cmpos;
216 cvPoint op, p4[4], T, ppp, ppp1, op1, op2;
220 GLfloat light_position[4];
223 /* Select current tunnel texture */
225 glBindTexture(GL_TEXTURE_2D, textures[current_texture]);
228 /* Get current curve */
229 if (cam_pos->next->next->next)
248 /* Get current camera position */
249 cvCatmullRom(p4, cam_t, &op);
251 /* Next camera position */
256 cmpos = cam_pos->next;
259 /* Get curve for next camera position */
260 if (cmpos->next->next->next)
279 /* Get next camera position */
280 cvCatmullRom(p4, cam_t, &op1);
283 glRotatef(alpha, 0, 0, -1);
285 /* Set camera position */
286 gluLookAt(op.x, op.y, op.z, op1.x, op1.y, op1.z, 0, 1, 0);
288 /* Set light position */
291 light_position[0] = op.x;
292 light_position[1] = op.y;
293 light_position[2] = op.z;
294 light_position[3] = 1;
295 glLightfv(GL_LIGHT0, GL_POSITION, light_position);
302 /* Draw tunnel from current curve and next 2 curves */
306 if (p->next->next->next)
324 cvCatmullRom(p4, t, &op);
338 if (p->next->next->next)
357 cvCatmullRom(p4, t, &op1);
361 ppp1.z = op1.z + 0.25;
371 RotateAroundLine(&ppp, &op, &T, ((float)i*36.0*M_PI/180.0), &op2);
377 prev_points[i].x = op2.x;
378 prev_points[i].y = op2.y;
379 prev_points[i].z = op2.z;
389 /* Draw 10 polygons for current point */
394 glNormal3f(0, 0, 1); /* Normal for lighting */
395 glTexCoord2f(0, 0); glVertex3f(prev_points[i].x, prev_points[i].y, prev_points[i].z);
397 glTexCoord2f(1, 0); glVertex3f(points[i].x, points[i].y, points[i].z);
399 glTexCoord2f(1, 1); glVertex3f(points[j].x, points[j].y, points[j].z);
401 glTexCoord2f(0, 1); glVertex3f(prev_points[j].x, prev_points[j].y, prev_points[j].z);
403 /* Save current polygon coordinates for next position */
406 prev_points[i].x = points[i].x;
407 prev_points[i].y = points[i].y;
408 prev_points[i].z = points[i].z;
415 /* =================== Show splash screen =================================== */
416 void SplashScreen(int do_wire, int do_texture, int do_light)
420 /* Reset tunnel and camera position */
428 if (current_texture > 2) current_texture = 0;
430 /* Now we want to draw splash screen */
432 /* Disable all unused features */
433 glDisable(GL_DEPTH_TEST);
434 glDisable(GL_LIGHTING);
436 glDisable(GL_CULL_FACE);
438 glBlendFunc(GL_SRC_ALPHA, GL_DST_ALPHA);
440 glDisable(GL_TEXTURE_2D);
441 glColor4f(1, 1, 1, ModeX);
443 /* Draw splash screen (simply quad) */
445 glVertex3f(-10, -10, -1);
446 glVertex3f(10, -10, -1);
447 glVertex3f(10, 10, -1);
448 glVertex3f(-10, 10, -1);
452 if (ModeX <= 0) ModeX = 0;
456 glEnable(GL_CULL_FACE);
457 glEnable(GL_DEPTH_TEST);
461 glEnable(GL_LIGHTING);
466 glEnable(GL_TEXTURE_2D);
469 glColor4f(1, 1, 1, 1);