Week06

1.  期中考題 (常用程式)

glPushMatrix();  //Push備份矩陣

    glTranslatef( x, y, z);  //移動

    glRotatf( angle, x, y, z); //旋轉

    glScalef( x, y, z);  //縮放

    glBegin(GL_POLYGON);  //開始畫

        glNormal3f( nx, ny, nz):  //法向量

        glTexCoord2f( tx, ty);  //貼圖座標

        glColor3f( r, g, b);  //色彩

        glVertex3f( x, y, z);  //頂點

    glEnd();

glPopMatrix();  //Pop還原矩陣

2.  材質 照光

3   茶壺立體照光

#include <GL/glut.h>

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 };///那負號是使光的方向是正面

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 };

void display()
{
     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
     glutSolidTeapot(0.3);
     glutSwapBuffers();
}

int main(int argc, char**argv)
{
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH);
    glutCreateWindow("hello3D");

    glutDisplayFunc(display);

    glClearColor(1,1,1,1);
    glEnable(GL_CULL_FACE);
    glCullFace(GL_BACK);

    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();
}

.

4.  可將照光的角度隨滑鼠做調整

.

#include <GL/glut.h>

const GLfloat light_ambient[]  = { 0.0f, 0.0f, 0.0f, 1.0f };
const GLfloat light_diffuse[]  = { 1.0f, 0.0f, 0.0f, 1.0f };
const GLfloat light_specular[] = { 1.0f, 0.0f, 0.0f, 1.0f };
GLfloat light_position[] = { 2.0f, 5.0f, -5.0f, 0.0f };///那負號是使光的方向是正面

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 };

void display()
{
     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
     glutSolidTeapot(0.3);
     glutSwapBuffers();
}
#include <stdio.h>
void motion(int x , int y)
{
    light_position[0]=(x-150)/150.0;
    light_position[1]=-(y-150)/150.0;
    glLightfv(GL_LIGHT0, GL_POSITION , light_position);
    glutPostRedisplay();
    printf("%f %f\n",light_position[0],light_position[1]);
}

int main(int argc, char**argv)
{
     glutInit(&argc, argv);
     glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH);
     glutCreateWindow("hello 3D");
     glutDisplayFunc(display);
     glutMotionFunc(motion);

    glClearColor(1,1,1,1);
    glEnable(GL_CULL_FACE);
    glCullFace(GL_BACK);

    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();
}