3-1：画点，连成线
// OPENGL.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
void init(void)
{
glClearColor(1.0, 1.0, 0.0, 0.0);
glMatrixMode(GL_PROJECTION);
gluOrtho2D(-10.0, 10.0, -10.0, 10.0);
}
void lineSegment(void)
{
glClear(GL_COLOR_BUFFER_BIT);
glColor3f(0.0, 0.4, 0.2);
glBegin(GL_LINES);
glVertex2i(10,10);
glVertex2i(-10,-10);
glVertex2i(-10, 0);
glVertex2i(10, 0);
glVertex2i(0, -10);
glVertex2i(0, 10);
glEnd();
glFlush();
}
int main(int argc, char *argv[])
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
glutInitWindowPosition(100,100);
glutInitWindowSize(800, 400);
glutCreateWindow("第一个OpenGL程序");
init();//设置背景，坐标系
glutDisplayFunc(lineSegment);//
glutMainLoop();
return 0;
}
4-1
// OPENGL.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#define Pi 3.1415926
void init(void)
{
glClearColor(1.0, 1.0, 1.0, 0.0);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(-200.0, 200.0, -200.0, 200.0);
}
//rho = a(1-sint(theta))
//x = a(1 - sin(t))*cos(t)
//y = a(1 - sin(t))*sin(t)
void circleDisplay(void)
{
float t;
glClear(GL_COLOR_BUFFER_BIT);
srand((unsigned)time(NULL));
glColor3f(1.0, 0.0, 0.0);
glLineWidth(10.0);
glBegin(GL_LINE_LOOP);
for (int i = 0; i < 1000; i++)
{
t = -1 * Pi / 2+ 2 * i * Pi / 1000;
glVertex2f(100*(1 - sin(t))*cos(t), 100*(1 - sin(t))*sin(t));
}
glEnd();
glFlush();
}
int main(int argc, char *argv[])
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
glutInitWindowPosition(50,100);
glutInitWindowSize(800, 800);
glutCreateWindow("第一个OpenGL程序");
glClearColor(1.0, 1.0, 1.0, 0.0);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(-200.0, 200.0, -200.0, 200.0);
glutDisplayFunc(circleDisplay);
glutMainLoop();
return 0;
}
4-2
// OPENGL.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#define Pi 3.1415926
float a = 60.0;
void circleDisplay(void)
{
double rr, gg, bb;
float x, y;
glClear(GL_COLOR_BUFFER_BIT);
glColor3f(1.0, 0.0, 0.0);
glLineWidth(5.0);
//cout << "a=" << a << endl;
glBegin(GL_LINE_STRIP);
for (int i = 0; i <= 10000; i++)
{
x = -5 + 10.0 * i / 10000;
glVertex2f(x, pow(x * x, 1.0 / 3.0) + 0.9 * sqrt(3.3 - x * x) * sin(a * Pi * x));
//glVertex2f(x, x * x);
}
glEnd();
glFlush();
}
void SpecialKeys(int key, int x, int y)
{
if (key == GLUT_KEY_UP)
a = a + 0.25;
glutPostRedisplay();
}
int main(int argc, char *argv[])
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
glutInitWindowPosition(50,100);
glutInitWindowSize(800, 800);
glutCreateWindow("第一个OpenGL程序");
glClearColor(1.0, 1.0, 1.0, 0.0);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(-3.0, 3.0, -3.0, 3.0);
glutDisplayFunc(circleDisplay);
//glutSpecialFunc(SpecialKeys);
glutMainLoop();
return 0;
}
4-3:point
// OPENGL.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#define Pi 3.1415926
void init(void)
{
glClearColor(1.0, 1.0, 1.0, 0.0);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(-200.0, 200.0, -200.0, 200.0);
}
void circleDisplay(void)
{
double rr, gg, bb;
float x, y;
glClear(GL_COLOR_BUFFER_BIT);
srand((unsigned)time(NULL));
glPointSize(10.0);
glBegin(GL_POINTS);
for (int i = 0; i < 1000; i++)
{
rr = rand() / double(RAND_MAX);
gg = rand() / double(RAND_MAX);
bb = rand() / double(RAND_MAX);
x = (rand() % (400 + 1)) - 200;
y = (rand() % (400 + 1)) - 200;
glColor3d(rr, gg, bb);
glVertex2f(x, y);
}
glEnd();
glFlush();
}
int main(int argc, char *argv[])
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
glutInitWindowPosition(50,100);
glutInitWindowSize(800, 800);
glutCreateWindow("第一个OpenGL程序");
glClearColor(1.0, 1.0, 1.0, 0.0);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(-200.0, 200.0, -200.0, 200.0);
glutDisplayFunc(circleDisplay);
glutMainLoop();
return 0;
}
5-1:bitmap显示字体
// OPENGL.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#define Pi 3.1415926
void init(void)
{
glClearColor(1.0, 1.0, 1.0, 0.0);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(-200.0, 200.0, -200.0, 200.0);
}
void circleDisplay(void)
{
glClear(GL_COLOR_BUFFER_BIT);
glColor3f(0.0, 0.0, 1.0);
glRasterPos2i(0,0);
glutBitmapCharacter(GLUT_BITMAP_HELVETICA_18, 'A');
glutBitmapCharacter(GLUT_BITMAP_HELVETICA_18, 'B');
glutBitmapCharacter(GLUT_BITMAP_HELVETICA_18, 'C');
glutBitmapCharacter(GLUT_BITMAP_TIMES_ROMAN_24, 'D');
glFlush();
}
int main(int argc, char *argv[])
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
glutInitWindowPosition(50,100);
glutInitWindowSize(800, 800);
glutCreateWindow("第一个OpenGL程序");
init();
glutDisplayFunc(circleDisplay);
glutMainLoop();
return 0;
}
6-1:blending
// OPENGL.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#define Pi 3.1415926
int windowWidth = 600, windowHeight = 600;
void init(void)
{
glClearColor(1.0, 1.0, 1.0, 1.0);
glEnable(GL_BLEND);
//glBlendFunc(GL_ONE, GL_ZERO);// sFactor, dFactor
//glBlendFunc(GL_ZERO, GL_ONE);// sFactor, dFactor
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
//glBlendFunc(GL_ONE, GL_ONE);
}
void myDisplay(void)
{
glClear(GL_COLOR_BUFFER_BIT);
glColor4f(1.0, 0.0, 0.0, 0.9);
glRecti(-50, -50, 100, 100);
glColor4f(0.0, 1.0, 0.0, 0.9);
glRecti(-100, -100, 50, 50);
glFlush();
}
void windowReshape(int w, int h)
{
float aspectRatio;
windowWidth = w;
windowHeight = h;
if (windowHeight == 0) windowHeight = 1;
aspectRatio = (float)windowWidth / (float)windowHeight;
glViewport(0, 0, windowWidth, windowHeight);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
if (windowWidth >= windowHeight)
gluOrtho2D(-100.0*aspectRatio, 100.0*aspectRatio, -100.0, 100.0);
else gluOrtho2D(-100.0, 100.0, -100.0 / aspectRatio, 100.0 / aspectRatio);
}
int main(int argc, char *argv[])
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGB | GLUT_SINGLE);
glutInitWindowPosition(100, 100);
glutInitWindowSize(windowWidth, windowHeight);
glutCreateWindow("第一个OpenGL程序");
init();
glutReshapeFunc(windowReshape);
glutDisplayFunc(myDisplay);
glutMainLoop();
return 0;
}
6-2:reshape
// OPENGL.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#define Pi 3.1415926
int windowWidth = 600, windowHeight = 600;
void init(void)
{
glClearColor(1.0, 1.0, 1.0, 1.0);
}
void myDisplay(void)
{
glClear(GL_COLOR_BUFFER_BIT);
glColor3f(1.0, 0.0, 0.0);
glRectf(-50.0,-50.0, 50.0, 50.0);
glFlush();
}
void windowReshape(int w, int h)
{
float aspectRatio;
windowWidth = w;
windowHeight = h;
aspectRatio = (float)windowWidth / (float)windowHeight;
//if (windowHeight == 0) windowHeight = 1;
//aspectRatio = (float)windowWidth / (float)windowHeight;
glViewport(0, 0, windowWidth, windowHeight);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
if (windowWidth >= windowHeight)
gluOrtho2D(-100.0*aspectRatio, 100.0*aspectRatio, -100.0, 100.0);
else gluOrtho2D(-100.0, 100.0, -100.0 / aspectRatio, 100.0/aspectRatio);
}
int main(int argc, char *argv[])
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGBA | GLUT_SINGLE);
glutInitWindowPosition(100,100);
glutInitWindowSize(windowWidth, windowHeight);
glutCreateWindow("第一个OpenGL程序");
init();
glutReshapeFunc(windowReshape);
glutDisplayFunc(myDisplay);
glutMainLoop();
return 0;
}
6-3:smooth
// OPENGL.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#define Pi 3.1415926
int windowWidth = 600, windowHeight = 600;
void init(void)
{
glClearColor(1.0, 1.0, 1.0, 1.0);
//glEnable(GL_BLEND);
//glBlendFunc(GL_ONE, GL_ZERO);// sFactor, dFactor
//glBlendFunc(GL_ZERO, GL_ONE);// sFactor, dFactor
//glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
//glBlendFunc(GL_ONE, GL_ONE);
}
void myDisplay(void)
{
double rr, gg, bb;
float t, x, y;
srand((unsigned)time(NULL));
glClear(GL_COLOR_BUFFER_BIT);
glShadeModel(GL_SMOOTH);
glBegin(GL_POLYGON);
glVertex2f(0.0, 0.0);
for (int i = 0; i <= 20; i++)
{
rr = rand() / double(RAND_MAX);
gg = rand() / double(RAND_MAX);
bb = rand() / double(RAND_MAX);
t = Pi *i / 20;
x = 60.0*cos(t);
y = 60.0*sin(t);
glColor3d(rr, gg, bb);
glVertex2f(x, y);
}
glEnd();
glFlush();
}
void windowReshape(int w, int h)
{
float aspectRatio;
windowWidth = w;
windowHeight = h;
if (windowHeight == 0) windowHeight = 1;
aspectRatio = (float)windowWidth / (float)windowHeight;
glViewport(0, 0, windowWidth, windowHeight);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
if (windowWidth >= windowHeight)
gluOrtho2D(-100.0*aspectRatio, 100.0*aspectRatio, -100.0, 100.0);
else gluOrtho2D(-100.0, 100.0, -100.0 / aspectRatio, 100.0 / aspectRatio);
}
int main(int argc, char *argv[])
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGB | GLUT_SINGLE);
glutInitWindowPosition(100, 100);
glutInitWindowSize(windowWidth, windowHeight);
glutCreateWindow("第一个OpenGL程序");
init();
glutReshapeFunc(windowReshape);
glutDisplayFunc(myDisplay);
glutMainLoop();
return 0;
}
7-1:antialiasing 消除锯齿
#include "stdafx.h"
#define Pi 3.1415926
int windowWidth = 600, windowHeight = 600;
void init(void)
{
glClearColor(1.0, 1.0, 1.0, 1.0);
glEnable(GL_LINE_SMOOTH);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA);
}
void myDisplay(void)
{
glClear(GL_COLOR_BUFFER_BIT);
glColor3f(0.0, 0.0, 1.0);
glLineWidth(200.0);
glBegin(GL_LINES);
glVertex2i(-5, -1);
glVertex2i(5, 1);
glEnd();
glFlush();
}
void windowReshape(int w, int h)
{
float aspectRatio;
windowWidth = w;
windowHeight = h;
aspectRatio = (float)windowWidth / (float)windowHeight;
glViewport(0, 0, windowWidth, windowHeight);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
if (windowWidth >= windowHeight)
gluOrtho2D(-10.0*aspectRatio, 10.0*aspectRatio, -10.0, 10.0);
else gluOrtho2D(-10.0, 10.0, -10.0 / aspectRatio, 10.0 / aspectRatio);
}
int main(int argc, char *argv[])
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGBA | GLUT_SINGLE);
glutInitWindowPosition(100, 100);
glutInitWindowSize(windowWidth, windowHeight);
glutCreateWindow("第一个OpenGL程序");
init();
glutReshapeFunc(windowReshape);
glutDisplayFunc(myDisplay);
glutMainLoop();
return 0;
}
7-2:fill area
#include "stdafx.h"
#define Pi 3.1415926
int windowWidth = 600, windowHeight = 600;
void init(void)
{
glClearColor(1.0, 1.0, 1.0, 1.0);
}
void myDisplay(void)
{
glClear(GL_COLOR_BUFFER_BIT);
//glColor3f(1.0, 0.0, 0.0);
//glBegin(GL_TRIANGLES);
//glVertex2i(-50, -50);
//glVertex2i(50, -50);
//glVertex2i(0, 50);
//glEnd();
//glColor3f(1.0, 0.0, 0.0);
//glBegin(GL_POLYGON);
//glVertex2i(-50, 0); glVertex2i(-25, -50);
//glVertex2i(25, -50); glVertex2i(50, 0);
//glVertex2i(25, 50); glVertex2i(-25, 50);
//glEnd();
//glShadeModel(GL_SMOOTH);//GL_FLAT
//glBegin(GL_TRIANGLES);
//glColor3f(1.0, 0.0, 0.0); glVertex2i(-50, -50);
//glColor3f(0.0, 1.0, 0.0); glVertex2i(50, -50);
//glColor3f(0.0, 0.0, 1.0); glVertex2i(0, 50);
//glEnd();
//glShadeModel(GL_SMOOTH);//GL_FLAT
//glBegin(GL_POLYGON);
//glColor3ub(255, 0, 0); glVertex2i(-50, 0);
//glColor3ub(255, 97, 0); glVertex2i(-25, -50);
//glColor3ub(255, 255, 0); glVertex2i(25, -50);
//glColor3ub(0, 255, 0); glVertex2i(50, 0);
//glColor3ub(0, 255, 255); glVertex2i(25, 50);
//glColor3ub(0, 0, 255); glVertex2i(-25, 50);
//glEnd();
//glShadeModel(GL_SMOOTH);//GL_FLAT
//glBegin(GL_POLYGON);
//glColor3ub(255, 0, 0); glVertex2i(-50, 0);
//glColor3ub(255, 255, 0); glVertex2i(-25, -50);
//glColor3ub(255, 255, 0); glVertex2i(25, -50);
//glColor3ub(255, 0, 0); glVertex2i(50, 0);
//glEnd();
glFlush();
}
void windowReshape(int w, int h)
{
float aspectRatio;
windowWidth = w;
windowHeight = h;
aspectRatio = (float)windowWidth / (float)windowHeight;
glViewport(0, 0, windowWidth, windowHeight);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
if (windowWidth >= windowHeight)
gluOrtho2D(-100.0*aspectRatio, 100.0*aspectRatio, -100.0, 100.0);
else gluOrtho2D(-100.0, 100.0, -100.0 / aspectRatio, 100.0 / aspectRatio);
}
int main(int argc, char *argv[])
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGBA | GLUT_SINGLE);
glutInitWindowPosition(100, 100);
glutInitWindowSize(windowWidth, windowHeight);
glutCreateWindow("第一个OpenGL程序");
init();
glutReshapeFunc(windowReshape);
glutDisplayFunc(myDisplay);
glutMainLoop();
return 0;
}
7-3:line-type
// OPENGL.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#define Pi 3.1415926
void init(void)
{
glClearColor(1.0, 1.0, 1.0, 1.0);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(-10.0, 10.0, -10.0, 10.0);
}
void circleDisplay(void)
{
glClear(GL_COLOR_BUFFER_BIT);
glEnable(GL_LINE_STIPPLE);
glLineWidth(10.0f);
glColor3f(0.0, 0.0, 0.0);
glLineStipple(1, 0x0101);
glBegin(GL_LINES);
glVertex2f(-5.0,-5.0);
glVertex2f(5.0, 5.0);
glEnd();
glFlush();
}
int main(int argc, char *argv[])
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_SINGLE | GLUT_RGBA);
glutInitWindowPosition(50,100);
glutInitWindowSize(800, 800);
glutCreateWindow("第一个OpenGL程序");
init();
glutDisplayFunc(circleDisplay);
glutMainLoop();
return 0;
}
