opengl实验2_opengl实验2交互_

// OpenGLexp2.cpp : 此文件包含 "main" 函数。程序执行将在此处开始并结束。 // #include <iostream> #include<GL/glut.h> #include<stdlib.h> #include "OpenGLexp2.h" #define Line 1 #define Triangle 2 #define Rectangle 4 GLfloat x = 0.0; GLfloat y= 0.0; GLfloat size = 50.0; GLsizei wh = 500, ww = 500; GLint index=Rectangle; void drawSquare(GLint x, GLint y) { y = wh - y; switch (index) { case Line: glBegin(GL_LINES); glVertex3f(x+size,y,0); glVertex3f(x-size,y,0); glEnd(); break; case Triangle: glBegin(GL_TRIANGLES); glVertex3f(x,y+size,0); glVertex3f(x+size*1.34,y-0.5*size,0); glVertex3f(x-size*1.34,y-0.5*size,0); glEnd(); break; case Rectangle: glBegin(GL_POLYGON); glVertex3f(x + size, y + size, 0); glVertex3f(x - size, y + size, 0); glVertex3f(x - size, y - size, 0); glVertex3f(x + size, y - size, 0); glEnd(); break; default: break; } } void myDisplay() { glClear(GL_COLOR_BUFFER_BIT); glColor3f(1.0, 1.0, 0.0); drawSquare(x, y); glutSwapBuffers(); glutPostRedisplay(); } void init() { glClearColor(0.0, 0.0, 0.0, 1.0); } void myReshape(GLint w, GLint h) { glViewport(0, 0, w, h); glMatrixMode(GL_PROJECTION); glLoadIdentity(); glOrtho(0, w, 0, h, -1.0, 1.0); glMatrixMode(GL_MODELVIEW); ww = w; wh = h; } void myMouse(GLint button, GLint state, GLint wx, GLint wy) { if (button == GLUT_RIGHT_BUTTON && state == GLUT_DOWN) { } if (button == GLUT_LEFT_BUTTON && state == GLUT_DOWN) { x = wx; y = wy; } } void processMenuEvents(int option) { switch (option) { case Line: index = Line; break; case Triangle: index = Triangle; break; case Rectangle: index = Rectangle; break; default: break; } } void createGLUTMenus() { int menu; menu = glutCreateMenu(processMenuEvents); glutAddMenuEntry("Line", Line); glutAddMenuEntry("Triangle",Triangle); glutAddMenuEntry("Rectangle", Rectangle); glutAttachMenu(GLUT_RIGHT_BUTTON); } void main(int argc, char** argv) { glutInit(&argc, argv); glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB); glutInitWindowSize(500, 500); glutInitWindowPosition(0, 0); glutCreateWindow("click to display square"); init(); glutDisplayFunc(myDisplay); glutReshapeFunc(myReshape); glutMouseFunc(myMouse); createGLUTMenus(); glutMainLoop(); }