weeek04 矮矮的筆記

來源 : http://www.cmlab.csie.ntu.edu.tw/~jsyeh/3dcg10/

1.下載 data

2.下載 win32 並解壓縮(放到你想放的地方

3.下載 glut32.dll 並複製到與win32同一個地方

4.解data壓縮至與win32同一個地方

.

5.執行Transformation.exe

試著挑整方向

用安培右手定則去試者想如何旋轉

glTranslate f(x , y , z) ; //移動

glRotatef ( angle , x , y , z ); // 轉動

glScalef ( x , y , z ) ; // 放大縮小

glBegin ( GL_POLYGON ) ; //開始畫

        glColor3f ( r , g , b ) ; // 顏色

       glVertex3f (x , y , z ) ; //頂點

glEnd() ; // 結束畫 glBegin()對應

glPopMatrix() ; //還原矩陣

(期中重點

茶壺轉動(自動)：

display()內新增
glPushMatrix();
     glRotatef(angle,0,0,1);  ///選轉angle度
     glutSolidTeapot(0.3);
glPopMatrix();

新增void motion()
void motion(int x,int y){
    angle = x;
    glutPostRedisplay();
}

main()內新增：
glutMotionFunc(motion);

執行結果：

#include <stdio.h>

#include <GL/glut.h>  

float angle = 0 ;

void display()

{

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT ) ;

    glPushMatrix();///備份矩陣

        glRotatef(angle , 0 , 0 , 1);

        glutSolidTeapot(0.3);

    glPopMatrix(); /// 還原矩陣

    glutSwapBuffers();

    printf("%.1f\n",angle);

    angle++ ; /// 每次角度加1度

}

int main(int argc , char**argv)

{

    glutInit(&argc ,argv);

    glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH) ;

    glutCreateWindow("Week04 transformation");

    glutIdleFunc(display);///很閒/Idle,去重畫.

    glutDisplayFunc(display);

    glutMainLoop();

}

茶壺轉動(手動)：
display()內新增
glPushMatrix();
     glRotatef(angle,0,0,1);  ///選轉angle度
     glutSolidTeapot(0.3);
glPopMatrix();

新增void motion()
void motion(int x,int y){
    angle = x;
    glutPostRedisplay();
}

main()內新增：
glutMotionFunc(motion);

茶壺旋轉、移動(手動)：
程式外宣告：
float angle = 0, teapotX = 0, teapotY = 0;
int oldX = 0, oldY = 0, nowRotate = 0;

display()內新增：
glTranslatef(teapotX,teapotY,0);

新增void mouse()：
void mouse(int button, int state, int x, int y){
    if(button == GLUT_LEFT_BUTTON && state == GLUT_DOWN)    nowRotate = 1;
    ///如果是右鍵就旋轉
    if(button == GLUT_RIGHT_BUTTON && state == GLUT_DOWN)    nowRotate = 0;
    ///如果是左鍵就移動
    oldX = x; oldY = Y; ///按下的時候，把oldX, oldY記住
}

void motion()內修改：
void motion(int x,int y){
    if(nowRotate == 1)    angle += (x - oldX); ///去改變angle值 ///加上改變量
    else{
         teapotX += (x - oldX)/150.0;
         teapotY += (oldY - y)/150.0;
    }
    oldX = x;  oldY = y;
  glutPostRedisplay(); ///畫面重畫
}

執行結果：


#include <GL/glut.h>

float angle = 0,teapotX = 0,teapotY = 0;
int oldX = 0, oldY = 0, nowRotate = 0;

void display(){
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glPushMatrix();
        glTranslatef(teapotX,teapotY,0);
        glRotatef(angle,0,0,1);
        glutSolidTeapot(0.3);
    glPopMatrix();
    glutSwapBuffers();
}

void motion(int x,int y){
    if(nowRotate == 1)    angle += (x - oldX);
    else{
        teapotX += (x - oldX)/150.0;
        teapotY += (oldY - y)/150.0;
    }
    oldX = x;  oldY = y;

  glutPostRedisplay();
}

void mouse(int button, int state, int x, int y){
    if(button == GLUT_LEFT_BUTTON && state == GLUT_DOWN)    nowRotate = 1;
    if(button == GLUT_RIGHT_BUTTON && state == GLUT_DOWN)    nowRotate = 0;
    oldX = x; oldY = y;
}
int main(int argc,char** argv){
    glutInit(&argc,argv);
    glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH);
    glutCreateWindow("Week04");

    glutMotionFunc(motion);
    glutDisplayFunc(display);
    glutMouseFunc(mouse);
    glutMainLoop();

}