DDA、中点画线法、bresenham算法

// OGL1.cpp : Defines the entry point for the console application. // #include <stdlib.h> #include <stdio.h> #include "stdafx.h" #include "windows.h" #include <gl\gl.h> // Header File For The OpenGL32 Library #include <gl\glu.h> // Header File For The GLu32 Library #include <gl\glaux.h> // Header File For The Glaux Library #include <gl\glut.h> // Header File For The OpenGL32 tools Library #include<time.h> int postRedisplay = 0; int x = 0; int y = 0; int z = 1; int counter = 0; int sefDx0; int sefDy0; int sefDx1; int sefDy1; void init (void) { glClearColor (0.0, 1.0, 1.0, 0.0); // Set display-window color to white. glMatrixMode (GL_PROJECTION); // Set projection parameters. gluOrtho2D (0.0, 500.0, 0.0, 500.0); } void DDA(int x0, int y0, int x1, int y1){//普通画线方法 int x; float dx, dy ,y ,k; clock_t start,finish; double duration; dx = x1 - x0; dy = y1 - y0; k = dx / dy; y = y0; glClear (GL_COLOR_BUFFER_BIT); // Clear display window. glColor3f (1.0, 0.0, 0.0); // Set line segment color to red. glPointSize( 10.0f ); start = clock(); for(x = x0; x <= x1; x++){ glBegin(GL_POINTS); glVertex2i(x, y); glEnd(); glFlush(); y += k; finish = clock(); } duration = (double) (finish-start) / CLOCKS_PER_SEC; printf("普通画线法所用时间为%lf\n",duration); } void callBack(void){ DDA(0, 0 , 500, 500); } void MidlePoint_Line(int x0, int y0, int x1, int y1){//中点画线法 int a, b, d1, d2, d, x, y; clock_t start,finish; double duration; a = y0 - y1; b = x1 - x0; d = 2 * a + b; d1 = 2 * a; d2 = 2 * (a + b); x = x0; y = y0; glClear (GL_COLOR_BUFFER_BIT); // Clear display window. glColor3f (1.0, 0.0, 0.0); // Set line segment color to red. glPointSize( 5.0f ); glBegin(GL_POINTS); glVertex2i(x, y); glEnd(); glFlush(); start = clock(); while(x < x1){ if ( d < 0 ){ x++; y++; d += d2; } else{ x++; d += d1; } glBegin(GL_POINTS); glVertex2i(x, y); glEnd(); glFlush(); finish = clock(); } duration = (double) (finish-start) / CLOCKS_PER_SEC; printf("中点画线法所用时间为%lf\n",duration); } void Bresenham(int x0, int y0, int x1, int y1){//bresenham画线方法 int x, y, dx, dy, e, i; dx = x1 - x0; dy = y1 - y0; e = -dx; x = x0; y = y0; glClear (GL_COLOR_BUFFER_BIT); // Clear display window. glColor3f (1.0, 0.0, 0.0); // Set line segment color to red. glPointSize( 5.0f ); for( i = 0; i < dx; i++){ glBegin(GL_POINTS); glVertex2i(x, y); glEnd(); glFlush(); x++; e = e + 2 * dx; if(e >= 0){ y++; e = e - 2* dx; } } } void selfDefine(int button , int state, int x, int y){//自定义画线方法 if(state == GLUT_DOWN){ printf("%d,%d\n",x,500 - y); glBegin(GL_POINTS); glVertex2i(x,500 - y); glEnd(); glFlush(); counter++; } if(counter%2 == 0){ sefDx1 = x; sefDy1 = 500 - y; MidlePoint_Line(sefDx0,sefDy0,sefDx1,sefDy1); } if(counter%2 == 1){ glClear (GL_COLOR_BUFFER_BIT); // Clear display window. glColor3f (1.0, 0.0, 0.0); // Set line segment color to red. sefDx0 = x; sefDy0 = 500 - y; } } void MidPointCircle(int r){ int x, y; float d; x = 0; y = r; d = 6 - 4*r; glClear (GL_COLOR_BUFFER_BIT); // Clear display window. glColor3f (1.0, 0.0, 0.0); // Set line segment color to red. glBegin(GL_POINTS); glVertex2i(x,y); glEnd(); glFlush(); while(x<=y){ if(d<0) d += 8*x + 12; else{ d += 8*(x-y)+20; y--; } x++; glBegin(GL_POINTS); glVertex2i(x,y); glVertex2i(y,x); glEnd(); glFlush(); } } void Menu(int val){ switch(val){ case 1: DDA(0, 0, 500, 500); break; case 2: MidlePoint_Line(0, 0, 500, 500); break; case 3: Bresenham(0, 0, 500, 500);break; case 4: glutMouseFunc( selfDefine );break; case 5: MidPointCircle(250);break; case 6: exit(0);break; } } void showMenu(int button , int state, int x, int y){ glutCreateMenu(Menu); glutAttachMenu(GLUT_RIGHT_BUTTON); glutAddMenuEntry("DDA法", 1); glutAddMenuEntry("中点画线法", 2); glutAddMenuEntry("Bresenham算法", 3); glutAddMenuEntry("自定义起点终点",4); glutAddMenuEntry("中点画圆法",5); glutAddMenuEntry("Exit", 6); } void main (int argc, char** argv) { glutInit (&argc, argv); // Initialize GLUT. glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB); // Set display mode. glutInitWindowPosition (0, 0); // Set top-left display-window position. glutInitWindowSize (500, 500); // Set display-window width and height. glutCreateWindow ("An Example OpenGL Program"); // Create display window. init ( ); // Execute initialization procedure. glutDisplayFunc ( callBack ); // Send graphics to display window. glutMouseFunc( showMenu ); glutMainLoop ( ); // Display everything and wait. }