week05

依照上週步驟打開Light&Material，並右鍵點ruby觀察變化

把glut程式砍掉一些就能變成茶壺程式

#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 };

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_RGB | GLUT_DOUBLE | GLUT_DEPTH);

    glutCreateWindow("GLUT Shapes");

    glutDisplayFunc(display);

///打光也需要的3d depth test

    glEnable(GL_DEPTH_TEST);

    glDepthFunc(GL_LESS);

///打光1:開啟光線

    glEnable(GL_LIGHT0);

    glEnable(GL_NORMALIZE);

    glEnable(GL_COLOR_MATERIAL);

    glEnable(GL_LIGHTING);

///打光2:要設定light的設定值

    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);

///打光2.2:要把物體也設定好它的meterial

    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);

///其實原本177行程裡，有打光的程式

    glutMainLoop();

    return EXIT_SUCCESS;

}

增加能影響光線的程式碼

void motion(int x,int y)

{

   GLfloat light_position[] = {2.0f,5.0f,-5.0f,0.0f};

   light_position[0] = (x-150)/150.0 * 10;

   light_position[1] = -(y-150)/150.0 * 10;

   glLightfv(GL_LIGHT0,GL_POSITION, light_position);

   glutPostRedisplay();///貼post請glut重畫畫面;

}