OpenGL基本图形的绘制

1. 使用glColor,glPointSize 函数绘制三个不同颜色和大小的点

// T.cpp : Defines the entry point for the console application.

//

#include "stdafx.h"

#include

void Display(void) {

glClear(GL_COLOR_BUFFER_BIT);

glPointSize(5.0f);

glBegin(GL_POINTS);

glColor3f(1.0,0.0,0.0);

glVertex2f(0.3f,0.5f);

glEnd();

glPointSize(8.0f);

glBegin(GL_POINTS);

glColor3f(0.0,1.0,0.0);

glVertex2f(0.0f,0.0f);

glEnd();

glPointSize(10.0f);

glBegin(GL_POINTS);

glColor3f(0.0,0.0,1.0);

glVertex2f(-0.3f,-0.5f);

glEnd();

glFlush();

}

int main(int argc,char* argv[]) {

glutInit(&argc,argv);

glutInitDisplayMode(GLUT_RGB);

glutInitWindowPosition(200,200);

glutInitWindowSize(400,400);

glutCreateWindow("Three Point");

glutDisplayFunc(&Display);

glutMainLoop();

return 0;

}

2. 使用glColor,glLineWidth,glLineStripple 函数绘制实心、虚线及渐变色线

（1）实心线

// T.cpp : Defines the entry point for the console application.

//

#include "stdafx.h"

#include

void Display(void) {

glClear(GL_COLOR_BUFFER_BIT);

glColor3f(1.0,0.0,0.0);

glEnable(GL_LINE_STIPPLE);

glShadeModel(GL_SMOOTH);

glLineStipple(2,0xFFFF);

glLineWidth(2);

glBegin(GL_LINES);

glVertex2i(-100,0);

glVertex2i(100,0);

glEnd();

glFlush();

}

int main(int argc,char* argv[]) {

glutInit(&argc,argv);

glutInitDisplayMode(GLUT_RGB);

glutInitWindowPosition(200,200);

glutInitWindowSize(400,400);

glutCreateWindow("Solid Line");

glutDisplayFunc(&Display);

glutMainLoop();

return 0;

}

（2）虚线

// T.cpp : Defines the entry point for the console application. //

#include "stdafx.h"

#include

void Display(void) {

glClear(GL_COLOR_BUFFER_BIT);

glColor3f(1.0,0.0,0.0);

glEnable(GL_LINE_STIPPLE);

glShadeModel(GL_SMOOTH);

glLineStipple(4,0xAAAA);

glLineWidth(2);

glBegin(GL_LINES);

glVertex2i(-100,0);

glVertex2i(100,0);

glEnd();

glFlush();

}

int main(int argc,char* argv[]) {

glutInit(&argc,argv);

glutInitDisplayMode(GLUT_RGB);

glutInitWindowPosition(200,200);

glutInitWindowSize(400,400);

glutCreateWindow("Dotted Line");

glutDisplayFunc(&Display);

glutMainLoop();

return 0;

}

（3）渐变线

// T.cpp : Defines the entry point for the console application. //

#include "stdafx.h"

#include

GLuint Line;

void Initial(void) {

glClearColor(0.0f, 0.0f, 0.0f, 0.0f);

Line = glGenLists(1);

glNewList(Line, GL_COMPILE); glTranslatef(-50.0, 20.0, 0.0);

glColor3f(255.0, 0.0, 0.0);

glLineWidth(2);

glBegin(GL_LINES);

glColor3f(255.0, 0.0, 0.0);

glVertex2i(0,-20);

glColor3f(0.0, 0.0, 255.0);

glVertex2i(100,-20);

glEnd();

glEndList();

void ChangeSize(int w, int h) {

glViewport(0, 0, w, h);

glMatrixMode(GL_PROJECTION);

glLoadIdentity();

gluOrtho2D (-70.0f, 70.0f, -70.0f, 70.0f);

}

void Display(void) {

glClear(GL_COLOR_BUFFER_BIT);

glMatrixMode(GL_MODELVIEW);

glLoadIdentity();

glTranslatef(0.0, 0.0, 0.0);

glCallList(Line);

glFlush();

}

int main(int argc, char* argv[]) {

glutInit(&argc, argv);

glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB); glutInitWindowSize(600,450); glutInitWindowPosition(100,100);

} glutCreateWindow("渐变色线"); glutDisplayFunc(Display); glutReshapeFunc(ChangeSize); Initial(); glutMainLoop(); return 0;

3. 使用glColor,glPolygonMode 函数绘制纯色、渐变色、轮廓多边形

（1）纯色六边形

// a.cpp : Defines the entry point for the console application. //

#include "stdafx.h"

#include

void init(){

glClearColor (1.0, 1.0, 1.0, 0.0);

glMatrixMode (GL_PROJECTION);

gluOrtho2D (0.0, 200.0, 0.0, 150.0);

}

void polygon(void){

glClear(GL_COLOR_BUFFER_BIT);

int p1 [] = {20, 75};

int p2 [] = {60, 5};

int p3 [] = {140, 5};

int p4 [] = {180, 75};

int p5 [] = {140, 145};

int p6 [] = {60, 145};

glColor3f(0.0, 0.5, 1.0);

glBegin(GL_POLYGON);

glVertex2iv(p1);

glVertex2iv(p2);

glVertex2iv(p3);

glVertex2iv(p4);

glVertex2iv(p5);

glVertex2iv(p6);

glEnd();

glFlush();

}

void main(int argc, char *argv[])

{

glutInit(&argc, argv);

glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB); glutInitWindowSize(400, 300);

glutCreateWindow("纯色六边形");

init();

glutDisplayFunc(polygon);

glutMainLoop();

}

（2）渐变色六边形

// a.cpp : Defines the entry point for the console application. //

#include "stdafx.h"

#include

void init(){

glClearColor (1.0, 1.0, 1.0, 0.0);

glMatrixMode (GL_PROJECTION);

gluOrtho2D (0.0, 200.0, 0.0, 150.0);

}

void polygon(void){

glClear(GL_COLOR_BUFFER_BIT);

int p1 [] = {20, 75};

int p2 [] = {60, 5};

int p3 [] = {140, 5};

int p4 [] = {180, 75};

int p5 [] = {140, 145};

int p6 [] = {60, 145};

glColor3f(0.0, 0.5, 1.0);

glBegin(GL_POLYGON);

glColor3f(0.0,0.0,1.0);

glVertex2iv(p1);

glColor3f(0.0,1.0,0.0);

glVertex2iv(p2);

glColor3f(1.0,0.0,0.0);

glVertex2iv(p3);

glColor3f(0.0,0.0,1.0);

glVertex2iv(p4);

glColor3f(0.0,1.0,0.0);

glVertex2iv(p5);

glColor3f(1.0,0.0,0.0);

glVertex2iv(p6);

glEnd();

glFlush();

}

void main(int argc, char *argv[])

{

glutInit(&argc, argv);

glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB); glutInitWindowSize(400, 300);

glutCreateWindow("渐变色六边形");

init();

glutDisplayFunc(polygon);

glutMainLoop();

}

（3）轮廓渐变色六边形

// a.cpp : Defines the entry point for the console application. //

#include "stdafx.h"

#include

void init(){

glClearColor (1.0, 1.0, 1.0, 0.0);

glPolygonMode (GL_FRONT_AND_BACK,GL_LINE); gluOrtho2D (0.0, 200.0, 0.0, 150.0);

}

void polygon(void){

glClear(GL_COLOR_BUFFER_BIT);

int p1 [] = {20, 75};

int p2 [] = {60, 5};

int p3 [] = {140, 5};

int p4 [] = {180, 75};

int p5 [] = {140, 145};

int p6 [] = {60, 145};

glColor3f(0.0, 0.5, 1.0);

glBegin(GL_POLYGON);

glColor3f(0.0,0.0,1.0);

glVertex2iv(p1);

glColor3f(0.0,1.0,0.0);

glVertex2iv(p2);

glColor3f(1.0,0.0,0.0);

glVertex2iv(p3);

glColor3f(0.0,0.0,1.0);

glVertex2iv(p4);

glColor3f(0.0,1.0,0.0);

glVertex2iv(p5);

glColor3f(1.0,0.0,0.0);

glVertex2iv(p6);

glEnd();

glFlush();

}

void main(int argc, char *argv[])

{

glutInit(&argc, argv);

glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB); glutInitWindowSize(400, 300);

glutCreateWindow("轮廓渐变色六边形"); init();

glutDisplayFunc(polygon);

glutMainLoop(); }