電腦圖學Week05筆記

 1.課前介紹

電腦圖學之父 - 伊凡·蘇澤蘭(Ivan Sutherland)

及他的老師 - Shannon 的 Ultimate machine (Unless machine)

2.今天的程式

(1)

#include <GL/glut.h>

#include <stdio.h>

void display()

{

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glColor3f(1,1,0);

    glutSolidTeapot(0.3);

    glutSwapBuffers();

}

void keyboard( unsigned char key, int x, int y)

{

    printf("按下的 %c 在 %d %d 座標\n", key, x, y);

}

int main(int argc, char**argv)

{

    glutInit(&argc, argv);

    glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH);

    glutCreateWindow("Week05 keyboard");

    glutDisplayFunc(display);

    glutKeyboardFunc(keyboard);

    glutMainLoop();

}

(當滑鼠放在任意一個地方時，按下任意一個鍵，則會顯示滑鼠箭頭所在的座標)

(2)將上一個程式進行修改

#include <GL/glut.h>

#include <stdio.h>

void display()

{

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glColor3f(1,1,0);

    glutSolidTeapot(0.3);

    glutSwapBuffers();

}

void keyboard( unsigned char key, int x, int y)

{

    

}

void mouse( int button, int state, int x, int y)

{

    

}

void motion( int x, int y)

{

    

}

int main(int argc, char**argv)

{

    glutInit(&argc, argv);

    glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH);

    glutCreateWindow("Week05 keyboard");

    glutDisplayFunc(display);

    glutKeyboardFunc(keyboard);

    glutMouseFunc(mouse);

    glutMotionFunc(motion);

    glutMainLoop();

}

(3)將上一個程式在進行修改

#include <GL/glut.h>

#include <stdio.h>

float x=0, y=0, z=0;

int oldX=0, oldY=0;

void display()

{

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glPushMatrix();

        glTranslatef( (x-150)/150.0, -(y-150)/150.0, z);

        glColor3f(1,1,0);

        glutSolidTeapot(0.3);

    glPopMatrix();

    glutSwapBuffers();

}

void keyboard( unsigned char key, int mouseX, int mouseY)

{

    

}

void mouse( int button, int state, int mouseX, int mouseY)

{

    

}

void motion( int mouseX, int mouseY)

{

    x+=(mouseX-oldX);

    y+=(mouseY-oldY);

    oldX = mouseX;

    oldY = mouseY;

    display();

}

int main(int argc, char**argv)

{

    glutInit(&argc, argv);

    glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH);

    glutCreateWindow("Week05 keyboard");

    glutDisplayFunc(display);

    glutKeyboardFunc(keyboard);

    glutMouseFunc(mouse);

    glutMotionFunc(motion);

    glutMainLoop();

}

(物體會隨著滑鼠移動)

(4)在進行修改

#include <GL/glut.h>

#include <stdio.h>

float x=150, y=150, z=0;

int oldX=0, oldY=0;

void display()

{

    glClearColor(0.5, 0.5, 0.5, 1);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glPushMatrix();

        glTranslatef( (x-150)/150.0, -(y-150)/150.0, z);

        glColor3f(1,1,0);

        glutSolidTeapot(0.3);

    glPopMatrix();

    glutSwapBuffers();

}

void keyboard( unsigned char key, int mouseX, int mouseY)

{

}

void mouse( int button, int state, int mouseX, int mouseY)

{

    oldX = mouseX;

    oldY = mouseY;

}

void motion( int mouseX, int mouseY)

{

    x+=(mouseX-oldX);

    y+=(mouseY-oldY);

    oldX = mouseX;

    oldY = mouseY;

    display();

}

int main(int argc, char**argv)

{

    glutInit(&argc, argv);

    glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH);

    glutCreateWindow("Week05 keyboard");

    glutDisplayFunc(display);

    glutKeyboardFunc(keyboard);

    glutMouseFunc(mouse);

    glutMotionFunc(motion);

    glutMainLoop();

}

(改變背景顏色。現在滑鼠不須直接點擊物品移動，在任意空白處點擊移動滑鼠即可移動物品)

(5)

#include <GL/glut.h>

#include <stdio.h>

float x=150, y=150, z=0, scale=1.0;

int oldX=0, oldY=0;

void display()

{

    glClearColor(0.5, 0.5, 0.5, 1);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glPushMatrix();

        glTranslatef( (x-150)/150.0, -(y-150)/150.0, z);

        glScalef(scale, scale, scale);

        glColor3f(1,1,0);

        glutSolidTeapot(0.3);

    glPopMatrix();

    glutSwapBuffers();

}

void keyboard( unsigned char key, int mouseX, int mouseY)

{

}

void mouse( int button, int state, int mouseX, int mouseY)

{

    oldX = mouseX;

    oldY = mouseY;

}

void motion( int mouseX, int mouseY)

{

    if(mouseX-oldX > 0) scale*=1.01;

    if(mouseX-oldX < 0) scale*=0.99;

    ///x+=(mouseX-oldX);

    ///y+=(mouseY-oldY);

    oldX = mouseX;

    oldY = mouseY;

    display();

}

int main(int argc, char**argv)

{

    glutInit(&argc, argv);

    glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH);

    glutCreateWindow("Week05 keyboard");

    glutDisplayFunc(display);

    glutKeyboardFunc(keyboard);

    glutMouseFunc(mouse);

    glutMotionFunc(motion);

    glutMainLoop();

}

(透過滑鼠將物品放大和縮小)