逃離電腦圖學 Week12

week12-1_printf_fprintf

#include <stdio.h>

int main()

{

    FILE*fout=fopen("file.txt","w");

    printf("Hello World\n");

    fprintf(fout,"Hello World在檔案裡\n");

}

week12-2_scanf_fscanf.cpp

#include <stdio.h>

int main()

{

    char line[20];

    FILE*fin=fopen("file.txt","r");

    fscanf(fin,"%s",line);

    printf("讀到了:%s\n",line);

    fscanf(fin,"%s",line);

    printf("讀到了:%s\n",line);

}

week12-3_many_numbers_scanf_printf_fscanf_fprintf

#include <stdio.h>

int main()

{

    int a[10]={10,20,30,40,50,60,70,80,90,100};

    FILE*fout=fopen("file3.txt","w");

    for(int i=0; i<10; i++){

        fprintf(fout,"%d ",a[i]);

        printf("%d ",a[i]);

    }

    fclose(fout);

    int b[10];

    FILE*fin=fopen("file3.txt","r");

    for(int i=0; i<10; i++){

        fscanf(fin,"%d",&b[i]);

        printf("%d ",b[i]);

    }

    fclose(fin);

}

week12-4_keyboard_mouse

#include <stdio.h>

#include <GL/glut.h>

float teapotX=0, teapotY=0;

void display()

{

    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);

    glPushMatrix();

        glTranslatef(teapotX, teapotY, 0);

        glutSolidTeapot(0.3);

    glPopMatrix();

    glutSwapBuffers();

}

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

{

    if(state==GLUT_DOWN){

        teapotX=(x-150)/150.0;

        teapotY=(150-y)/150.0;

    }

    display();

}

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

{

    glutInit(&argc, argv);

    glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);

    glutCreateWindow("week12");

    glutDisplayFunc(display);

    glutMouseFunc(mouse);

    glutMainLoop();

}

茶壺會跟著滑鼠點的位置

#include <stdio.h>

#include <GL/glut.h>

FILE*fout=NULL;///一開始檔案沒開,所以是NULL

FILE*fin=NULL;///要讀檔用的指標,一開始也是NULL

float teapotX=0, teapotY=0;

void display()

{

    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);

    glPushMatrix();

        glTranslatef(teapotX, teapotY, 0);

        glutSolidTeapot(0.3);

    glPopMatrix();

    glutSwapBuffers();

}

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

{

    if(state==GLUT_DOWN){

        teapotX=(x-150)/150.0;

        teapotY=(150-y)/150.0;

        if(fout==NULL) fout=fopen("file4.txt","w");

            fprintf(fout,"%f %f\n",teapotX,teapotY);

    }

    display();

}

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

{

    if(fin==NULL){///如果檔案還沒fopen(),就打開它

        fclose(fout);///前面mouse會開fout指標,所以要關掉

        fin=fopen("file4.txt","r");///沒開檔案就開它

    }

    fscanf(fin,"%f %f",&teapotX,&teapotY);///真的讀檔

    display();///重畫畫面

}

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

{

    glutInit(&argc, argv);

    glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);

    glutCreateWindow("week12");

    glutDisplayFunc(display);

    glutMouseFunc(mouse);

    glutKeyboardFunc(keyboard);///keyboard開檔讀檔

    glutMainLoop();

}

按鍵盤重複剛剛所點的位置