sheeba - week04 - 旋轉

Step01-1 

到 https://jsyeh.org/3dcg10/ 下載windows.zip,data.zip

解壓縮到   下載\windows

執行今天的課本範例 Transformation.exe

Step01-2

了解旋轉是如何運作   是用右手座標系統   把手掌從x掃到y時   由拇指決定z軸的方向

Step01-3

假如旋轉軸是(1,1,0)   人會怎麼轉   使用右手想像他會怎麼轉

Step02-1

建立GLUT專案   名稱week04-1_rotate   把今天教的glRotatef拿來用

#include <GL/glut.h>

float angle=0;///step02-2

void display()

{

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);///step02-2清背景

    glPushMatrix();///備份矩陣

        glRotatef(angle, 0, 1, 0);///step02-1旋轉angle

        glutSolidTeapot( 0.3 );

    glPopMatrix();///還原矩陣 step01-2

    glutSwapBuffers();

    angle++;///step02-1 把角度++

}

int main(int argc, char *argv[])

{

    glutInit(&argc, argv);

    glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);

glutCreateWindow("week03");

glutDisplayFunc(display);

glutIdleFunc(display);

glutMainLoop();

}

Step02-2

增加光線

///把week04-1的程式,copy來week04-2

#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 myLight()

{

        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);

}

float angle=0;///step02-2

void display()

{

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);///step02-2清背景

    glPushMatrix();///備份矩陣

        glRotatef(angle, 0, 1, 0);///step02-1旋轉angle

        glutSolidTeapot( 0.3 );

    glPopMatrix();///還原矩陣 step01-2

    glutSwapBuffers();

    angle++;///step02-1 把角度++

}

int main(int argc, char *argv[])

{

    glutInit(&argc, argv);

    glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);

glutCreateWindow("week04");

glutDisplayFunc(display);

glutIdleFunc(display);

    myLight();

glutMainLoop();

}

Step02-3

增加顏色

///把week04-1的程式,copy來week04-2

#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 myLight()

{

        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);

}

float angle=0;///step02-2

void display()

{

    glClearColor(1,1,1,1);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);///step02-2清背景

    glPushMatrix();///備份矩陣

        glRotatef(angle, 0, 1, 0);///step02-1旋轉angle

        glColor3f(1,1,0);

        glutSolidTeapot( 0.3 );

    glPopMatrix();///還原矩陣 step01-2

    glutSwapBuffers();

    angle++;///step02-1 把角度++

}

int main(int argc, char *argv[])

{

    glutInit(&argc, argv);

    glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);

glutCreateWindow("week04");

glutDisplayFunc(display);

glutIdleFunc(display);

    myLight();

glutMainLoop();

}

Step03-1

這兩週教的移動、旋轉   程式碼對調結果會不一樣

在下方按右鍵選swap translate rotate   交換這兩行

在邊邊自轉、繞著中心公轉

Step03-2

在week04-3_rotate_translate的範例裡實作  translate和rotate交換

///week04-3程式來自week04-1

#include <GL/glut.h>

float angle=0;///step02-2

void display()

{

    glEnable(GL_DEPTH_TEST);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);///step02-2清背景

    glPushMatrix();///備份矩陣

        glTranslatef(0.6, 0, 0);

        glRotatef(angle, 0, 1, 0);///step02-1旋轉angle

        glColor3f(1,1,0);

        glutSolidTeapot( 0.3 );

    glPopMatrix();///還原矩陣 step01-2

    glPushMatrix();///備份矩陣

        glRotatef(angle, 0, 1, 0);///step02-1旋轉angle

        glTranslatef(0.6, 0, 0);

        glColor3f(1,0,0);

        glutSolidTeapot( 0.3 );

    glPopMatrix();///還原矩陣 step01-2

    glutSwapBuffers();

    angle++;///step02-1 把角度++

}

int main(int argc, char *argv[])

{

    glutInit(&argc, argv);

    glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);

glutCreateWindow("week04");

glutDisplayFunc(display);

glutIdleFunc(display);

glutMainLoop();

}