summaryrefslogtreecommitdiffstats
path: root/examples/opengl/gear/gear.cpp
blob: 96152eedda7bf8afce583ad484036a5e27430ffa (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
/****************************************************************************
**
** Copyright (C) 1992-2008 Trolltech ASA.  All rights reserved.
**
** This file is part of an example program for TQt.  This example
** program may be used, distributed and modified without limitation.
**
*****************************************************************************/
//
// Draws a gear.
//
// Portions of this code have been borrowed from Brian Paul's Mesa
// distribution.
//

#include <tqgl.h>
#include <tqapplication.h>
#include <math.h>

#if defined(Q_CC_MSVC)
#pragma warning(disable:4305) // init: truncation from const double to float
#endif

/*
 * Draw a gear wheel.  You'll probably want to call this function when
 * building a display list since we do a lot of trig here.
 *
 * Input:  inner_radius - radius of hole at center
 *	   outer_radius - radius at center of teeth
 *	   width - width of gear
 *	   teeth - number of teeth
 *	   tooth_depth - depth of tooth
 */
static void gear( GLfloat inner_radius, GLfloat outer_radius, GLfloat width,
		  GLint teeth, GLfloat tooth_depth )
{
    GLint i;
    GLfloat r0, r1, r2;
    GLfloat angle, da;
    GLfloat u, v, len;

    r0 = inner_radius;
    r1 = outer_radius - tooth_depth/2.0;
    r2 = outer_radius + tooth_depth/2.0;

    const double pi = 3.14159264;
    da = 2.0*pi / teeth / 4.0;

    glShadeModel( GL_FLAT );

    glNormal3f( 0.0, 0.0, 1.0 );

    /* draw front face */
    glBegin( GL_QUAD_STRIP );
    for (i=0;i<=teeth;i++) {
	angle = i * 2.0*pi / teeth;
	glVertex3f( r0*cos(angle), r0*sin(angle), width*0.5 );
	glVertex3f( r1*cos(angle), r1*sin(angle), width*0.5 );
	glVertex3f( r0*cos(angle), r0*sin(angle), width*0.5 );
	glVertex3f( r1*cos(angle+3*da), r1*sin(angle+3*da), width*0.5 );
    }
    glEnd();

    /* draw front sides of teeth */
    glBegin( GL_QUADS );
    da = 2.0*pi / teeth / 4.0;
    for (i=0;i<teeth;i++) {
	angle = i * 2.0*pi / teeth;

	glVertex3f( r1*cos(angle),      r1*sin(angle),	  width*0.5 );
	glVertex3f( r2*cos(angle+da),   r2*sin(angle+da),	  width*0.5 );
	glVertex3f( r2*cos(angle+2*da), r2*sin(angle+2*da), width*0.5 );
	glVertex3f( r1*cos(angle+3*da), r1*sin(angle+3*da), width*0.5 );
    }
    glEnd();


    glNormal3f( 0.0, 0.0, -1.0 );

    /* draw back face */
    glBegin( GL_QUAD_STRIP );
    for (i=0;i<=teeth;i++) {
	angle = i * 2.0*pi / teeth;
	glVertex3f( r1*cos(angle), r1*sin(angle), -width*0.5 );
	glVertex3f( r0*cos(angle), r0*sin(angle), -width*0.5 );
	glVertex3f( r1*cos(angle+3*da), r1*sin(angle+3*da), -width*0.5 );
	glVertex3f( r0*cos(angle), r0*sin(angle), -width*0.5 );
    }
    glEnd();

    /* draw back sides of teeth */
    glBegin( GL_QUADS );
    da = 2.0*pi / teeth / 4.0;
    for (i=0;i<teeth;i++) {
	angle = i * 2.0*pi / teeth;

	glVertex3f( r1*cos(angle+3*da), r1*sin(angle+3*da), -width*0.5 );
	glVertex3f( r2*cos(angle+2*da), r2*sin(angle+2*da), -width*0.5 );
	glVertex3f( r2*cos(angle+da),   r2*sin(angle+da),	  -width*0.5 );
	glVertex3f( r1*cos(angle),      r1*sin(angle),	  -width*0.5 );
    }
    glEnd();


    /* draw outward faces of teeth */
    glBegin( GL_QUAD_STRIP );
    for (i=0;i<teeth;i++) {
	angle = i * 2.0*pi / teeth;

	glVertex3f( r1*cos(angle),      r1*sin(angle),	   width*0.5 );
	glVertex3f( r1*cos(angle),      r1*sin(angle),	  -width*0.5 );
	u = r2*cos(angle+da) - r1*cos(angle);
	v = r2*sin(angle+da) - r1*sin(angle);
	len = sqrt( u*u + v*v );
	u /= len;
	v /= len;
	glNormal3f( v, -u, 0.0 );
	glVertex3f( r2*cos(angle+da),   r2*sin(angle+da),	   width*0.5 );
	glVertex3f( r2*cos(angle+da),   r2*sin(angle+da),	  -width*0.5 );
	glNormal3f( cos(angle), sin(angle), 0.0 );
	glVertex3f( r2*cos(angle+2*da), r2*sin(angle+2*da),  width*0.5 );
	glVertex3f( r2*cos(angle+2*da), r2*sin(angle+2*da), -width*0.5 );
	u = r1*cos(angle+3*da) - r2*cos(angle+2*da);
	v = r1*sin(angle+3*da) - r2*sin(angle+2*da);
	glNormal3f( v, -u, 0.0 );
	glVertex3f( r1*cos(angle+3*da), r1*sin(angle+3*da),  width*0.5 );
	glVertex3f( r1*cos(angle+3*da), r1*sin(angle+3*da), -width*0.5 );
	glNormal3f( cos(angle), sin(angle), 0.0 );
    }

    glVertex3f( r1*cos(0.0), r1*sin(0.0), width*0.5 );
    glVertex3f( r1*cos(0.0), r1*sin(0.0), -width*0.5 );

    glEnd();


    glShadeModel( GL_SMOOTH );

    /* draw inside radius cylinder */
    glBegin( GL_QUAD_STRIP );
    for (i=0;i<=teeth;i++) {
	angle = i * 2.0*pi / teeth;
	glNormal3f( -cos(angle), -sin(angle), 0.0 );
	glVertex3f( r0*cos(angle), r0*sin(angle), -width*0.5 );
	glVertex3f( r0*cos(angle), r0*sin(angle), width*0.5 );
    }
    glEnd();

}


static GLfloat view_rotx=20.0, view_roty=30.0, view_rotz=0.0;
static GLint gear1, gear2, gear3;
static GLfloat angle = 0.0;


static void draw()
{
    angle += 2.0;
    view_roty += 1.0;

    glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );

    glPushMatrix();
    glRotatef( view_rotx, 1.0, 0.0, 0.0 );
    glRotatef( view_roty, 0.0, 1.0, 0.0 );
    glRotatef( view_rotz, 0.0, 0.0, 1.0 );

    glPushMatrix();
    glTranslatef( -3.0, -2.0, 0.0 );
    glRotatef( angle, 0.0, 0.0, 1.0 );
    glCallList(gear1);
    glPopMatrix();

    glPushMatrix();
    glTranslatef( 3.1, -2.0, 0.0 );
    glRotatef( -2.0*angle-9.0, 0.0, 0.0, 1.0 );
    glCallList(gear2);
    glPopMatrix();

    glPushMatrix();
    glTranslatef( -3.1, 2.2, -1.8 );
    glRotatef( 90.0, 1.0, 0.0, 0.0 );
    glRotatef( 2.0*angle-2.0, 0.0, 0.0, 1.0 );
    glCallList(gear3);
    glPopMatrix();

    glPopMatrix();
}


static int timer_interval = 10;			// timer interval (millisec)


class GearWidget : public TQGLWidget
{
public:
    GearWidget( TQWidget *parent=0, const char *name=0 );
protected:
    void initializeGL();
    void resizeGL( int, int );
    void paintGL();
    void timerEvent( TQTimerEvent * );
};

GearWidget::GearWidget( TQWidget *parent, const char *name )
     : TQGLWidget( parent, name )
{
    startTimer( timer_interval );
}

void GearWidget::initializeGL()
{
    static GLfloat pos[4] = {5.0, 5.0, 10.0, 1.0 };
    static GLfloat ared[4] = {0.8, 0.1, 0.0, 1.0 };
    static GLfloat agreen[4] = {0.0, 0.8, 0.2, 1.0 };
    static GLfloat ablue[4] = {0.2, 0.2, 1.0, 1.0 };

    glLightfv( GL_LIGHT0, GL_POSITION, pos );
    glEnable( GL_CULL_FACE );
    glEnable( GL_LIGHTING );
    glEnable( GL_LIGHT0 );
    glEnable( GL_DEPTH_TEST );

    /* make the gears */
    gear1 = glGenLists(1);
    glNewList(gear1, GL_COMPILE);
    glMaterialfv( GL_FRONT, GL_AMBIENT_AND_DIFFUSE, ared );
    gear( 1.0, 4.0, 1.0, 20, 0.7 );
    glEndList();

    gear2 = glGenLists(1);
    glNewList(gear2, GL_COMPILE);
    glMaterialfv( GL_FRONT, GL_AMBIENT_AND_DIFFUSE, agreen );
    gear( 0.5, 2.0, 2.0, 10, 0.7 );
    glEndList();

    gear3 = glGenLists(1);
    glNewList(gear3, GL_COMPILE);
    glMaterialfv( GL_FRONT, GL_AMBIENT_AND_DIFFUSE, ablue );
    gear( 1.3, 2.0, 0.5, 10, 0.7 );
    glEndList();

    glEnable( GL_NORMALIZE );
}


void GearWidget::resizeGL( int width, int height )
{
    GLfloat w = (float) width / (float) height;
    GLfloat h = 1.0;

    glViewport( 0, 0, width, height );
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glFrustum( -w, w, -h, h, 5.0, 60.0 );
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    glTranslatef( 0.0, 0.0, -40.0 );
}


void GearWidget::paintGL()
{
    draw();
}

void GearWidget::timerEvent(TQTimerEvent*)
{
    updateGL();
}



int main( int argc, char **argv )
{
    TQApplication::setColorSpec( TQApplication::CustomColor );
    TQApplication a( argc, argv );

    if ( !TQGLFormat::hasOpenGL() ) {
	tqWarning( "This system has no OpenGL support. Exiting." );
	return -1;
    }

    if ( argc >= 2 ) {
	bool ok = TRUE;
	timer_interval = TQString::fromLatin1( argv[1] ).toInt( &ok );
	if ( !ok )
	    timer_interval = 10;
    }

    GearWidget w;
    a.setMainWidget( &w );
    w.show();
    return a.exec();
}