CS计算机代考程序代写 /*

/*
Jernej Barbic
University of Southern California

A basic OpenGL program with GLUT.
*/

#include
#include
#include

// standard OpenGL include files
// the location of these files varies by platform
#if defined(WIN32) || defined(linux)
#include
#include
#include
#elif defined(__APPLE__)
#include
#include
#include
#endif

int windowID;
int windowWidth, windowHeight;
double angle = 0.0;
double cameraHeight = 1.0;

void Init()
{
// set the screen background color to RGB (200, 200, 45) (light yellow)
glClearColor(200.0 / 255, 200.0 / 255, 45.0 / 255, 0.0);

// enable the depth test (important; disabled by default)
glEnable(GL_DEPTH_TEST);

//glShadeModel(GL_FLAT); // shade the entire triangle with a flat color
glShadeModel(GL_SMOOTH); // interpolate vertex colors into the triangle interior
}

// this function gets called continuously (alternates execution with “Display”)
void DoIdle()
{
angle += 0.001; // one of the two triangles circles
//cameraHeight = 1.0;
cameraHeight = 1.0 + 0.5 * sin(2*angle); // camera moves up and down
glutPostRedisplay();
}

// this function gets called whenever the user resizes the window
// x = window x-size (in pixels)
// y = window y-size (in pixels)
void Reshape(int x, int y)
{
windowWidth = x;
windowHeight = y;

glViewport(0,0,x,y);

glMatrixMode(GL_PROJECTION); // select the projection matrix
glLoadIdentity(); // reset the projection matrix to identity

// Calculate The Aspect Ratio Of The Window
double minZPlane = 0.01;
double maxZPlane = 10.0;
double aspectRatio = 1.0 * windowWidth / windowHeight;
gluPerspective(45.0f, aspectRatio, minZPlane, maxZPlane);

glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
}

// this function gets called whenever a key is pressed
void KeyboardFunc (unsigned char key, int x, int y)
{
switch (key)
{
case 27:
// ESC pressed, exit the application
glutDestroyWindow(windowID);
exit(0);
break;

case ‘a’:
printf(“You pressed the ‘a’ key.
”);
break;

default:
break;
}
}

// this function gets called continuously (alternates execution with “DoIdle”)
void Display()
{
// clear the screen and the depth buffer
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

// select the modelview matrix
glMatrixMode(GL_MODELVIEW);
// clear the modelview matrix
glLoadIdentity();
// set the camera position
double cameraPosition[3] = {1.0, cameraHeight, 1.0};
double focusPosition[3] = {0, 0, 0};
double up[3] = {0,1,0};
gluLookAt( cameraPosition[0], cameraPosition[1], cameraPosition[2],
focusPosition[0], focusPosition[1], focusPosition[2],
up[0], up[1], up[2]);

// draw two triangles
glBegin(GL_TRIANGLES);

// === triangle 1 ===
// rotate the triangle along the y-axis

// vertex 1
// set the white color
glColor3f(1, 1, 1);
glVertex3f(0, 0, 0);

// vertex 2
// set the blue color
glColor3f(0, 0, 1);
glVertex3f(0, 0.2, 0); // vertex at (0, 0.2, 0)

// vertex 3
// set a weak hue of red
glColor3f(0.2, 0, 0);
glVertex3f(0.2 * cos(angle), 0, 0.2 * sin(angle));

// === triangle 2 ===

// vertex 1
// set the green color
glColor3f(0, 1, 0);
glVertex3f(0.2, 0, 0);

// vertex 2
// set black color
glColor3f(0, 0, 0);
glVertex3f(0.2, 0.2, 0);

// vertex 3
// set white color
glColor3f(1, 1, 1);
glVertex3f(0.4, 0, 0);

glEnd();

// render coordinate system axes
glLineWidth(3.0); // set line width
glBegin(GL_LINES);
glColor3f(1,0,0);
glVertex3f(0,0,0);
glVertex3f(0.5,0,0);
glColor3f(0,1,0);
glVertex3f(0,0,0);
glVertex3f(0,0.5,0);
glColor3f(0,0,1);
glVertex3f(0,0,0);
glVertex3f(0,0,0.5);
glEnd();

// swap buffers
// warning: do not forget this call, or else nothing will be drawn
glutSwapBuffers();
}

int main (int argc, char ** argv)
{
// init GLUT
glutInit(&argc,argv);

// double buffering, use RGBA colors, use depth buffer
glutInitDisplayMode (GLUT_DOUBLE | GLUT_RGBA | GLUT_DEPTH);

// create a 400×400 window
windowWidth = 400;
windowHeight = 400;
glutInitWindowSize (windowWidth,windowHeight);

// init window position on the screen
glutInitWindowPosition (0,0);

// set the window title
char s[4096] = “Hello world”;
windowID = glutCreateWindow(s);
//glutFullScreen(); // make window full-screen

// register the display callback
glutDisplayFunc(Display);

// register the reshape callback
glutReshapeFunc(Reshape);

// register the idle callback
glutIdleFunc(DoIdle);

// register the keyboard callback
glutKeyboardFunc(KeyboardFunc);

// call our initialization
Init();

// forever sink into an internal GLUT loop
glutMainLoop();

// we never reach this point
return(0);
}