UCC的第五週上課筆記~

>今日介紹 電腦圖學之父Ivan Sutherland --Sketchpad<

  step0-1 windows.zip =解壓=> 下載\windows\Transformation.exe

               data.zip =解壓=>下載\windows\data\模型.org

 step1-1 在CODEBLOCKS上開啟新專案在過去的程式碼(茶壺)貼上進行修改

         在MAIN裡建立一個glutKeyboardFunc(keyboard)函式

                 做完後可以看到每按一次鍵盤會跳出滑鼠所在的座標      

 step2-1  多加一些函示，使得茶壺可以透過滑鼠拖曳

<<char範圍:-128~128>>

   <<unsigned:不要加上負號，使得數字範圍從0~255>> 

<<callback函式:

 glutDisplayFunc(display);

    glutKeyboardFunc(keyboard);

    glutMouseFunc(mouse);

    glutMotionFunc(motion);

>>

 step3-1 結合前面教的mouse和motion函示

         將floatX,y數值進行改變，將程式更優化(圖案不卡頓)

(目前程式碼)

#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 motion(int mouseX,int mouseY)

 {

    x+=(mouseX-oldX); y+=(mouseY-oldY);

    oldX=mouseX; oldY=mouseY;

    display();

 }

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

 {

    oldX=mouseX; oldY=mouseY;

 }

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

 {

 }

 int main(int argc, char *argv[])//main()主函式 進階版

 {

    glutInit(&argc,argv);//把參數送給glutInit初始化

    glutInitDisplayMode(GLUT_DOUBLE|GLUT_DEPTH);//雙緩衝區+3D深度功能

    glutCreateWindow("week05");//開GLUT視窗

    glutDisplayFunc(display);//顯示用的函式

    glutKeyboardFunc(keyboard);

    glutMouseFunc(mouse);

    glutMotionFunc(motion);

    glutMainLoop();

 }

step4-1透過SCALE的X值來拉大拉小茶壺大小

            加入程式碼<<scale=1.0;

            if(mouseX-oldX>0) scale*=1.01;

            if(mouseX-oldX<0) scale*=0.99;

>最終程式碼<

#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 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();

 }

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

 {

    oldX=mouseX; oldY=mouseY;

 }

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

 {

 }

 int main(int argc, char *argv[])//main()主函式 進階版

 {

    glutInit(&argc,argv);//把參數送給glutInit初始化

    glutInitDisplayMode(GLUT_DOUBLE|GLUT_DEPTH);//雙緩衝區+3D深度功能

    glutCreateWindow("week05");//開GLUT視窗

    glutDisplayFunc(display);//顯示用的函式

    glutKeyboardFunc(keyboard);

    glutMouseFunc(mouse);

    glutMotionFunc(motion);

    glutMainLoop();

 }