dials2.c
上传用户:xk288cn
上传日期:2007-05-28
资源大小:4876k
文件大小:3k
- /* Copyright (c) Mark J. Kilgard, 1994. */
- /* This program is freely distributable without licensing fees
- and is provided without guarantee or warrantee expressed or
- implied. This program is -not- in the public domain. */
- #include <string.h>
- #include <stdio.h>
- #include <stdlib.h>
- #include <math.h>
- #include <GL/glut.h>
- #define NUM_DIALS 8
- #define NUM_BUTTONS 32
- int *dials, *buttons;
- #undef PI /* Some systems may have this defined. */
- #define PI 3.14159265358979323846
- void
- drawCircle(int x, int y, int r, int dir)
- {
- float angle;
- glPushMatrix();
- glTranslatef(x,y,0);
- glBegin(GL_TRIANGLE_FAN);
- glVertex2f(0,0);
- for(angle = 2*PI; angle >= 0; angle -= PI/12) {
- glVertex2f(r*cos(angle),r*sin(angle));
- }
- glEnd();
- glColor3f(0,0,1);
- glBegin(GL_LINES);
- glVertex2f(0,0);
- glVertex2f(r*cos(dir*PI/180),r*sin(dir*PI/180));
- glEnd();
- glPopMatrix();
- }
- void
- displayDials(void)
- {
- int i;
- for(i=0;i<NUM_DIALS;i++) {
- glColor3f(0, 1, 0);
- drawCircle(60 + ((i+1)%2) * 100, 60 + (i/2) * 100, 40, dials[NUM_DIALS-1-i]-90);
- }
- }
- void
- displayButtons(void)
- {
- int i, n;
- glBegin(GL_QUADS);
- for(i=0,n=0;i<NUM_BUTTONS;i++,n++) {
- switch(n) {
- case 0:
- case 5:
- case 30:
- n++;
- }
- if(buttons[i]) {
- glColor3f(1,0,0);
- } else {
- glColor3f(1,1,1);
- }
- glVertex2f((n%6)*40+250,(n/6)*40+10);
- glVertex2f((n%6)*40+270,(n/6)*40+10);
- glVertex2f((n%6)*40+270,(n/6)*40+30);
- glVertex2f((n%6)*40+250,(n/6)*40+30);
- }
- glEnd();
- }
- void
- display(void)
- {
- glClear(GL_COLOR_BUFFER_BIT);
- displayDials();
- displayButtons();
- glutSwapBuffers();
- }
- void
- reshape(int w, int h)
- {
- glViewport(0, 0, w, h);
- glMatrixMode(GL_PROJECTION);
- glLoadIdentity();
- gluOrtho2D(0, w, 0, h);
- glScalef(1, -1, 1);
- glTranslatef(0, -h, 0);
- }
- void
- dodial(int dial, int value)
- {
- if(dial > 0 && dial <= NUM_DIALS) {
- dials[dial - 1] = value % 360;
- glutPostRedisplay();
- }
- }
- void
- dobutton(int button, int state)
- {
- if(button > 0 && button <= NUM_BUTTONS) {
- buttons[button-1] = (state == GLUT_DOWN);
- glutPostRedisplay();
- }
- }
- int
- main(int argc, char **argv)
- {
- int width, height;
- glutInit(&argc, argv);
- dials = (int*) calloc(NUM_DIALS, sizeof(int));
- buttons = (int*) calloc(NUM_BUTTONS, sizeof(int));
- glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB);
- width = 240 + 240;
- height = 100*((NUM_DIALS+1)/2) + 20;
- if(height < 240) height = 240;
- glutInitWindowSize(width, height);
- glutCreateWindow("GLUT dials & buttons");
- glClearColor(0.5, 0.5, 0.5, 1.0);
- glLineWidth(3.0);
- glutDialsFunc(dodial);
- glutButtonBoxFunc(dobutton);
- glutDisplayFunc(display);
- glutReshapeFunc(reshape);
- glutInitWindowSize(240, 240);
- glutMainLoop();
- return 0; /* ANSI C requires main to return int. */
- }