#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 };
float x=150, y=150, z=0, scale=1.0, angle=0.0;
int oldX=0, oldY=0, now=1;///1.移動 2.旋轉 3.縮放
void display()
{
glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );///畫圖前, 先清畫面
glPushMatrix();///備份矩陣
glTranslatef((x-150)/150.0,-(y-150)/150.0,z);///移動
glRotatef(angle, 0, 1, 0);///對Y軸旋轉
glScalef(scale, scale, scale);///縮放成scale倍+
glColor3f(1,1,0);///黃色
glutSolidTeapot(0.3);
glPopMatrix();///還原矩陣
glutSwapBuffers();///畫好後,交換出來
}
void keyboard(unsigned char key, int mouseX, int mouseY){///輸入中文會被os擋住
if(key=='1' || key=='w' || key=='W')now=1;///移動
if(key=='2' || key=='e' || key=='E')now=2;///旋轉
if(key=='3' || key=='r' || key=='R')now=3;///縮放
}
void mouse(int button, int state, int mouseX, int mouseY){
///為了解決瞬間移動的問題,改用延續拖移
oldX=mouseX;
oldY=mouseY;
}
void motion(int mouseX,int mouseY){
if(now==1){
x+=(mouseX-oldX);///移動
y+=(mouseY-oldY);
}
else if(now==2){
angle += (mouseX - oldX);///旋轉
}
else if(now==3){
if(mouseX-oldX>0) scale *=1.01;///縮放
if(mouseX-oldX<0) scale *=0.99;
}
oldX=mouseX;
oldY=mouseY;
display();///重畫
}
int main(int argc,char** argv)
{
glutInit(&argc,argv);
glutInitDisplayMode( GLUT_DOUBLE | GLUT_DEPTH);
glutCreateWindow("week06 Light");
glutDisplayFunc(display);
glEnable(GL_DEPTH_TEST);///3D功能
glDepthFunc(GL_LIGHT0);///定義一盞燈
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);
glutKeyboardFunc(keyboard);///第0代主角
glutMouseFunc(mouse);///第一代主角
glutMotionFunc(motion);///第二代主角
glutMainLoop(); ///主要的程式迴圈
}