tri.c revision 32001f49 
1/*
2 * Copyright (c) 1991, 1992, 1993 Silicon Graphics, Inc.
3 *
4 * Permission to use, copy, modify, distribute, and sell this software and
5 * its documentation for any purpose is hereby granted without fee, provided
6 * that (i) the above copyright notices and this permission notice appear in
7 * all copies of the software and related documentation, and (ii) the name of
8 * Silicon Graphics may not be used in any advertising or
9 * publicity relating to the software without the specific, prior written
10 * permission of Silicon Graphics.
11 *
12 * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF
13 * ANY KIND,
14 * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
15 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
16 *
17 * IN NO EVENT SHALL SILICON GRAPHICS BE LIABLE FOR
18 * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
19 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
20 * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
21 * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
22 * OF THIS SOFTWARE.
23 */
24
25#include <stdio.h>
26#include <string.h>
27#include <stdlib.h>
28#include "glut_wrap.h"
29
30
31#define	SOLID 1
32#define	LINE 2
33#define	POINT 3
34
35
36GLenum rgb, doubleBuffer, windType;
37GLint windW, windH;
38
39GLenum dithering = GL_TRUE;
40GLenum showVerticies = GL_TRUE;
41GLenum hideBottomTriangle = GL_FALSE;
42GLenum outline = GL_TRUE;
43GLenum culling = GL_FALSE;
44GLenum winding = GL_FALSE;
45GLenum face = GL_FALSE;
46GLenum state = SOLID;
47GLenum aaMode = GL_FALSE;
48GLenum shade = GL_TRUE;
49
50GLint color1, color2, color3;
51
52float zRotation = 90.0;
53float zoom = 1.0;
54
55float boxA[3] = {-100, -100, 0};
56float boxB[3] = { 100, -100, 0};
57float boxC[3] = { 100,  100, 0};
58float boxD[3] = {-100,  100, 0};
59
60float p0[3] = {-125,-80, 0};
61float p1[3] = {-125, 80, 0};
62float p2[3] = { 172,  0, 0};
63
64
65#include "tkmap.c"
66
67static void Init(void)
68{
69    float r, g, b;
70    float percent1, percent2;
71    GLint i, j;
72
73    glClearColor(0.0, 0.0, 0.0, 0.0);
74
75    glLineStipple(1, 0xF0F0);
76
77    glEnable(GL_SCISSOR_TEST);
78
79    if (!rgb) {
80	for (j = 0; j <= 12; j++) {
81	    if (j <= 6) {
82		percent1 = j / 6.0;
83		r = 1.0 - 0.8 * percent1;
84		g = 0.2 + 0.8 * percent1;
85		b = 0.2;
86	    } else {
87		percent1 = (j - 6) / 6.0;
88		r = 0.2;
89		g = 1.0 - 0.8 * percent1;
90		b = 0.2 + 0.8 * percent1;
91	    }
92	    glutSetColor(j+18, r, g, b);
93	    for (i = 0; i < 16; i++) {
94		percent2 = i / 15.0;
95		glutSetColor(j*16+1+32, r*percent2, g*percent2, b*percent2);
96	    }
97	}
98	color1 = 18;
99	color2 = 24;
100	color3 = 30;
101    }
102}
103
104static void Reshape(int width, int height)
105{
106
107    windW = (GLint)width;
108    windH = (GLint)height;
109}
110
111static void Key2(int key, int x, int y)
112{
113
114    switch (key) {
115      case GLUT_KEY_LEFT:
116	zRotation += 0.5;
117	break;
118      case GLUT_KEY_RIGHT:
119	zRotation -= 0.5;
120	break;
121      default:
122	return;
123    }
124
125    glutPostRedisplay();
126}
127
128static void Key(unsigned char key, int x, int y)
129{
130
131    switch (key) {
132      case 27:
133	exit(1);
134      case 'Z':
135	zoom *= 0.75;
136	break;
137      case 'z':
138	zoom /= 0.75;
139	if (zoom > 10) {
140	    zoom = 10;
141	}
142	break;
143      case '1':
144	glPolygonMode(GL_FRONT_AND_BACK, GL_POINT);
145	break;
146      case '2':
147	glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
148	break;
149      case '3':
150	glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
151	break;
152      case '4':
153	state = POINT;
154	break;
155      case '5':
156	state = LINE;
157	break;
158      case '6':
159	state = SOLID;
160	break;
161      case '7':
162	culling = !culling;
163	break;
164      case '8':
165	winding = !winding;
166	break;
167      case '9':
168	face = !face;
169	break;
170      case 'v':
171	showVerticies = !showVerticies;
172	break;
173      case 's':
174	shade = !shade;
175	(shade) ? glShadeModel(GL_SMOOTH) : glShadeModel(GL_FLAT);
176	break;
177      case 'h':
178	hideBottomTriangle = !hideBottomTriangle;
179	break;
180      case 'o':
181	outline = !outline;
182	break;
183      case 'm':
184	dithering = !dithering;
185	break;
186      case '0':
187	aaMode = !aaMode;
188	if (aaMode) {
189	    glEnable(GL_POLYGON_SMOOTH);
190	    glEnable(GL_BLEND);
191	    glBlendFunc(GL_SRC_ALPHA, GL_ONE);
192	    if (!rgb) {
193		color1 = 32;
194		color2 = 128;
195		color3 = 224;
196	    }
197	} else {
198	    glDisable(GL_POLYGON_SMOOTH);
199	    glDisable(GL_BLEND);
200	    if (!rgb) {
201		color1 = 18;
202		color2 = 24;
203		color3 = 30;
204	    }
205	}
206	break;
207      default:
208	return;
209    }
210
211    glutPostRedisplay();
212}
213
214static void BeginPrim(void)
215{
216
217    switch (state) {
218      case SOLID:
219	glBegin(GL_POLYGON);
220	break;
221      case LINE:
222	glBegin(GL_LINE_LOOP);
223	break;
224      case POINT:
225	glBegin(GL_POINTS);
226	break;
227      default:
228        break;
229    }
230}
231
232static void EndPrim(void)
233{
234
235    glEnd();
236}
237
238static void Draw(void)
239{
240    float scaleX, scaleY;
241
242    glViewport(0, 0, windW, windH);
243
244    glMatrixMode(GL_PROJECTION);
245    glLoadIdentity();
246    gluOrtho2D(-175, 175, -175, 175);
247    glMatrixMode(GL_MODELVIEW);
248
249    glScissor(0, 0, windW, windH);
250
251    (culling) ? glEnable(GL_CULL_FACE) : glDisable(GL_CULL_FACE);
252    (winding) ? glFrontFace(GL_CCW) : glFrontFace(GL_CW);
253    (face) ? glCullFace(GL_FRONT) : glCullFace(GL_BACK);
254
255    (dithering) ? glEnable(GL_DITHER) : glDisable(GL_DITHER);
256
257    glClear(GL_COLOR_BUFFER_BIT);
258
259    SetColor(COLOR_GREEN);
260    glBegin(GL_LINE_LOOP);
261	glVertex3fv(boxA);
262	glVertex3fv(boxB);
263	glVertex3fv(boxC);
264	glVertex3fv(boxD);
265    glEnd();
266
267    if (!hideBottomTriangle) {
268	glPushMatrix();
269
270	glScalef(zoom, zoom, zoom);
271	glRotatef(zRotation, 0, 0, 1);
272
273	SetColor(COLOR_BLUE);
274	BeginPrim();
275	    glVertex3fv(p0);
276	    glVertex3fv(p1);
277	    glVertex3fv(p2);
278	EndPrim();
279
280	if (showVerticies) {
281	    (rgb) ? glColor3fv(RGBMap[COLOR_RED]) : glIndexf(color1);
282	    glRectf(p0[0]-2, p0[1]-2, p0[0]+2, p0[1]+2);
283	    (rgb) ? glColor3fv(RGBMap[COLOR_GREEN]) : glIndexf(color2);
284	    glRectf(p1[0]-2, p1[1]-2, p1[0]+2, p1[1]+2);
285	    (rgb) ? glColor3fv(RGBMap[COLOR_BLUE]) : glIndexf(color3);
286	    glRectf(p2[0]-2, p2[1]-2, p2[0]+2, p2[1]+2);
287	}
288
289	glPopMatrix();
290    }
291
292    scaleX = (float)(windW - 20) / 2 / 175 * (175 - 100) + 10;
293    scaleY = (float)(windH - 20) / 2 / 175 * (175 - 100) + 10;
294
295    glViewport(scaleX, scaleY, windW-2*scaleX, windH-2*scaleY);
296
297    glMatrixMode(GL_PROJECTION);
298    glLoadIdentity();
299    gluOrtho2D(-100, 100, -100, 100);
300    glMatrixMode(GL_MODELVIEW);
301
302    glScissor(scaleX, scaleY, windW-2*scaleX, windH-2*scaleY);
303
304    glPushMatrix();
305
306    glScalef(zoom, zoom, zoom);
307    glRotatef(zRotation, 0,0,1);
308
309    glPointSize(10);
310    glLineWidth(5);
311    glEnable(GL_POINT_SMOOTH);
312    glEnable(GL_LINE_STIPPLE);
313    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
314
315    SetColor(COLOR_RED);
316    BeginPrim();
317	(rgb) ? glColor3fv(RGBMap[COLOR_RED]) : glIndexf(color1);
318	glVertex3fv(p0);
319	(rgb) ? glColor3fv(RGBMap[COLOR_GREEN]) : glIndexf(color2);
320	glVertex3fv(p1);
321	(rgb) ? glColor3fv(RGBMap[COLOR_BLUE]) : glIndexf(color3);
322	glVertex3fv(p2);
323    EndPrim();
324
325    glPointSize(1);
326    glLineWidth(1);
327    glDisable(GL_POINT_SMOOTH);
328    glDisable(GL_LINE_STIPPLE);
329    glBlendFunc(GL_ONE, GL_ZERO);
330
331    if (outline) {
332	SetColor(COLOR_WHITE);
333	glBegin(GL_LINE_LOOP);
334	    glVertex3fv(p0);
335	    glVertex3fv(p1);
336	    glVertex3fv(p2);
337	glEnd();
338    }
339
340    glPopMatrix();
341
342    glFlush();
343
344    if (doubleBuffer) {
345	glutSwapBuffers();
346    }
347}
348
349static GLenum Args(int argc, char **argv)
350{
351    GLint i;
352
353    rgb = GL_TRUE;
354    doubleBuffer = GL_FALSE;
355
356    for (i = 1; i < argc; i++) {
357	if (strcmp(argv[i], "-ci") == 0) {
358	    rgb = GL_FALSE;
359	} else if (strcmp(argv[i], "-rgb") == 0) {
360	    rgb = GL_TRUE;
361	} else if (strcmp(argv[i], "-sb") == 0) {
362	    doubleBuffer = GL_FALSE;
363	} else if (strcmp(argv[i], "-db") == 0) {
364	    doubleBuffer = GL_TRUE;
365	} else {
366	    printf("%s (Bad option).\n", argv[i]);
367	    return GL_FALSE;
368	}
369    }
370    return GL_TRUE;
371}
372
373int main(int argc, char **argv)
374{
375    glutInit(&argc, argv);
376
377    if (Args(argc, argv) == GL_FALSE) {
378	exit(1);
379    }
380
381    windW = 600;
382    windH = 300;
383    glutInitWindowPosition(0, 0); glutInitWindowSize( windW, windH);
384
385    windType = (rgb) ? GLUT_RGB : GLUT_INDEX;
386    windType |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
387    glutInitDisplayMode(windType);
388
389    if (glutCreateWindow("Triangle Test") == GL_FALSE) {
390	exit(1);
391    }
392
393    InitMap();
394
395    Init();
396
397    glutReshapeFunc(Reshape);
398    glutKeyboardFunc(Key);
399    glutSpecialFunc(Key2);
400    glutDisplayFunc(Draw);
401    glutMainLoop();
402	return 0;
403}
404