week15

0.Projection
*fovy:fov(Field of View)在y的方向
 *aspect:長寬比










1.完成茶壺的運鏡 旋轉是攝影機在旋轉,不是茶壺在動

#include <GL/glut.h>
static void resize(int width, int height)///留下resize()
{
 const float ar = (float) width / (float) height;
 glViewport(0, 0, width, height);
 glMatrixMode(GL_PROJECTION);
 glLoadIdentity();
 gluPerspective(60, ar, 0.01, 1000);///我們改了它!!!
 glMatrixMode(GL_MODELVIEW);
 glLoadIdentity() ;///原本只有2行, 沒有運鏡
 ///需要運鏡時, 要加上第3行 gluLookAt()
}
static void display(void)
{
 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 glutSolidTeapot(0.3);
 glutSwapBuffers();
}
#include <math.h>///要用到數學
float eyeX=0, eyeY=0, eyeZ=1;///TODO
float angle=0;
static void idle(void)
{
 eyeX=sin(angle);
 eyeZ=cos(angle);
 angle+=0.01;
 glMatrixMode(GL_MODELVIEW);
 glLoadIdentity() ;///原本只有2行, 沒有運鏡
 gluLookAt(eyeX, eyeY, eyeZ, 0,0,0, 0,1,0); ///因為要運鏡所以需要 gluLookAt()
 glutPostRedisplay();
}
void motion(int x, int y)
{
 eyeY = (y-240)/240.0;
}
const GLfloat light_ambient[] = { 0.0f, 0.0f, 0.0f, 1.0f };
const GLfloat light_diffuse[] = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat light_specular[] = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat light_position[] = { 2.0f, 5.0f, 5.0f, 0.0f };
const GLfloat mat_ambient[] = { 0.7f, 0.7f, 0.7f, 1.0f };
const GLfloat mat_diffuse[] = { 0.8f, 0.8f, 0.8f, 1.0f };
const GLfloat mat_specular[] = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat high_shininess[] = { 100.0f };
/* Program entry point */
int main(int argc, char *argv[])
{
 glutInit(&argc, argv);
 glutInitWindowSize(640,480);
 glutInitWindowPosition(10,10);
 glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);
 glutCreateWindow("GLUT Shapes");
 glutReshapeFunc(resize);
 glutDisplayFunc(display);
 glutIdleFunc(idle);
 glutMotionFunc(motion);///控制 eyeY
 glClearColor(1,1,1,1);
 glEnable(GL_DEPTH_TEST);
 glDepthFunc(GL_LESS);
 glEnable(GL_LIGHT0);
 glEnable(GL_NORMALIZE);
 glEnable(GL_COLOR_MATERIAL);
 glEnable(GL_LIGHTING);
 glLightfv(GL_LIGHT0, GL_AMBIENT, light_ambient);
 glLightfv(GL_LIGHT0, GL_DIFFUSE, light_diffuse);
 glLightfv(GL_LIGHT0, GL_SPECULAR, light_specular);
 glLightfv(GL_LIGHT0, GL_POSITION, light_position);
 glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);
 glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
 glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
 glMaterialfv(GL_FRONT, GL_SHININESS, high_shininess);
 glutMainLoop();
 return EXIT_SUCCESS;
}