// Bo qua man hinh Console#pragma comment( linker,
"/subsystem:\"windows\" /entry:\"mainCRTStartup\"" )
#include #include "GL/glut.h"
#include #include #include
// hang so PI#define M_PI 3.14159265358979// macro doi tu do
--> radian#define RAD(goc) ((goc)*(M_PI/180.0))// macro doi tu
radian --> goc#define GOC(rad) ((rad)*180.0/M_PI)// ham lam
tron#define ROUND(n) ((int)(n+0.5))
// cau truc 1 thanh phan mau theo RGBstruct colorentry {
unsigned char red; unsigned char green; unsigned char blue;
colorentry(int r, int g, int :red(r),green(g), blue({};}; //
colorentry
// -------------------------------------// CAC HAM XU SU KIEN//
-------------------------------------// khoi tao thong sovoid
OnInit();// ham su kien vevoid OnDraw();// ham su kien thay doi
kich thuoc cua sovoid OnSize(int width,int height);// ham su kien
nhan phimvoid OnKey(unsigned char key,int x, int y);// ham su kien
nhan phim mo rongvoid OnKeySpecial(int key,int x, int y);// ham su
kien Idlevoid OnIdle();// ham su kien thoi gianvoid OnTime(int
ms);// ham su kien nhan chuotvoid OnMouse(int btn, int state, int
x, int y);// ham su kien di chuyen chuot va nhanvoid OnMotion(int
x, int y);// ham su kien di chuyen chuot va khong nhanvoid
OnPassiveMotion(int x, int y);
// -------------------------------------// KHAI BAO CAC HAM VA
BIEN// -------------------------------------int _xc, _yc;
void DrawSquareRotate(int xc, int yc, int w, int dgoc,
colorentry c);
int main(int argc, char* argv[]){ //
------------------------------------- // KHOI TAO CUA SO OPENGL //
------------------------------------- // khoi tao tham so cua so
glutInit(&argc, argv); // che do hien thi: double buffer va he
mau RGB glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB); // do rong,
cao cua cua so glutInitWindowSize(640, 480); // vi tri bat dau cua
so glutInitWindowPosition(0, 0); // tao cua so glutCreateWindow("Ve
hinh vuong xoay!"); // ------------------------------------- // CAC
THAO TAC XU LY // -------------------------------------
OnInit();
// ------------------------------------- // DANG KY SU KIEN //
------------------------------------- // dang ky su kien ve
glutDisplayFunc(OnDraw); // dang ky su kien thay doi kich thuoc cua
so glutReshapeFunc(OnSize); // dang ky su kien nhan phim
glutKeyboardFunc(OnKey); // dang ky su kien nhan phim mo rong
glutSpecialFunc(OnKeySpecial); // Dang ky thoi gian 0.5s
glutTimerFunc(100,OnTime,100); // dang ky su kien Idle
glutIdleFunc(OnIdle); // dang ky su kien nhan chuot
glutMouseFunc(OnMouse); // dang ky su kien di chuyen va nhan chuot
glutMotionFunc(OnMotion); // dang ky su kien di chuyen va khong
nhan chuot glutPassiveMotionFunc(OnMotion);
// ------------------------------------- // VONG LAP SU KIEN //
------------------------------------- glutMainLoop();
return 0;}int n;void OnInit(){ // thiet lap mau xoa
glClearColor(0.0,0.0,0.0,0.0); int xMax =
glutGet(GLUT_WINDOW_WIDTH); int yMax = glutGet(GLUT_WINDOW_HEIGHT);
n=7; _xc = xMax/2; _yc = yMax/2;
}// OnInit
void OnDraw(){ // xoa man hinh glClear(GL_COLOR_BUFFER_BIT);
// cac thao tac ve int _w=100; //GLint
_dgoc[]={0,8,16,24,32,40,48,56}; int _dgoc=0; for(int i=0;i30);
//DrawSquareRotate(_xc,_yc,_w,_dgoc,colorentry(255,0,0)); else
DrawSquareRotate(_xc,_yc,_w,_dgoc,colorentry(255,0,0)); _w-=2;
_dgoc+=2; } // ket xuat ra man hinh glFlush(); // chuyen tien canh
sang hau canh va nguoc lai (double buffer) glutSwapBuffers();}//
Display
void OnTime(int ms){ // Ham xu ly thoi gian// _dgoc = (_dgoc+5)
% 360;
// Lap lai cho lan ke tiep glutTimerFunc(ms,OnTime,ms);}//
OnTime
void OnIdle(){ // yeu cau ve lai man hinh cua so
glutPostRedisplay();}// OnIdle
void OnMouse(int btn, int state, int x, int y){ int xMax =
glutGet(GLUT_WINDOW_WIDTH); int yMax = glutGet(GLUT_WINDOW_HEIGHT);
_xc = x; _yc = yMax-y;}// OnMouse
void OnMotion(int x, int y){ int xMax =
glutGet(GLUT_WINDOW_WIDTH); int yMax = glutGet(GLUT_WINDOW_HEIGHT);
// xx = x; // yy = yMax-y;}// OnMotion
void OnSize(int width,int height){ // thiet lap khung hien thi
cua cua so glViewport(0, 0 , (GLsizei)width,(GLsizei)height); //
thiet lap phep chieu glMatrixMode(GL_PROJECTION); // ma tran bien
doi la ma tran don vi glLoadIdentity(); // bien doi toa do
gluOrtho2D(0,(GLdouble)width,0, (GLdouble)height);}// OnSize
void OnKey(unsigned char key,int x, int y){ switch(key) { case
3: // (Ctrl+C) case 27: // (ESC) exit(0); break; case 'x': // (ESC)
n++; break; case 'z': // (ESC) n--; break; }// switch key}//
OnKey
void OnKeySpecial(int key,int x, int y){ // printf("%d",key);
switch(key) { case 100: // LEFT _xc -= 5; break; case 101: // UP
_yc += 5; break; case 102: // RIGHT _xc += 5; break; case 103: //
DOWN _yc -= 5; break; }}// OnKeySpecial
void DrawSquareRotate(int xc, int yc, int w, int dgoc,
colorentry c){ float xi, yi; //GLint goc[] = { 135, 45, 315, 225,
135 }; GLfloat R = sqrt(w*w+w*w); glBegin(GL_LINE_LOOP);
glColor3ub(c.red,c.green,c.blue); for(int i=0;i ta chn ng phn gic
thuc BC vi mu 10 BresenhamLine(xa,(int)xi,ya,(int)yi,10);
}
