白貓茶熊 and 公連聖千同時大爆死之week8

一.期中考題OpenGL必背函式

glPushMatrix();///備份矩陣 10%

   glTranslatef(x,y,z);///移動 10%

   glRotatef(angle,x,y,z)///轉動 10%

   glScalef(x,y,z)///放大縮小 10%

glBegin(GL_POLYGON);///開始畫 10%

   glColor3f(r,g,b)///顏色 10%

   glTexCoord2f(tx,ty);///貼圖座標 10%

   glNormal3f(nx,ny,nz);///法向量 10%

   glVertex2f(x,y);///頂點 10%

glEnd();///結束畫

glPopMatrix();///還原矩陣 10%

二.打光 Light

CodeBlocks打開GLUT，其設定如同以往

輸入以下程式碼

#include <GL/glut.h>

///外面陣列到第一個light，是陣列的宣告，裡面有光的值

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 };

///裡面有Material的值

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("week7");

    glutDisplayFunc(display);

    ///打開第一個燈光

    glEnable(GL_LIGHT0);

    glEnable(GL_NORMALIZE);

    glEnable(GL_COLOR_MATERIAL);

    glEnable(GL_LIGHTING);

    ///光的設定值

    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);

    ///Material設定值

    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();

}

運行結果如下

三.打光 (用滑鼠調整光照方向)

CodeBlocks打開GLUT，其設定如同以往

輸入以下程式碼(藍字是新增)

#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 };

GLfloat light_position[] = { 2.0f, 5.0f, -5.0f, 0.0f };///新:需刪掉const,const表示不能動的函數

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();

}

void motion(int x,int y)///新:改light_position[]的值,呼叫函式

{

    light_position[0]=(x-150)/150.0;///新:光源的X座標

    light_position[1]=-(y-150)/150.0;///新:光源的Y座標

    glLightfv(GL_LIGHT0, GL_POSITION, light_position);

    glutPostRedisplay();///新:重畫畫面

}

int main (int argc,char**argv)

{

    glutInit(&argc,argv);

    glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);

    glutCreateWindow("week7");

    glutDisplayFunc(display);

    glutMotionFunc(motion);///新:讓mouse motion可以改變光源的位置

    glEnable(GL_DEPTH_TEST);///新:

    ///開啟3D的深淺測試=>近的會蓋掉遠的

    ///打開第一個燈光

    glEnable(GL_LIGHT0);

    glEnable(GL_NORMALIZE);

    glEnable(GL_COLOR_MATERIAL);

    glEnable(GL_LIGHTING);

    ///光的設定值

    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);

    ///Material設定值

    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();

}

運行結果如下