sheeba - week15 - Camera 投影 運鏡

 Step01-1

到https://jsyeh.org/3dcg10/下載windows.zip、data.zip

將下載好的windows檔案與data檔案解壓縮   把data丟到windows裡

開啟projection.exe調整數值觀察

Step02-1

建立GLUT專案   命名為week15-1_gluPerspective

#include <GLUT/glut.h>

#else

#include <GL/glut.h>

#endif

#include <stdlib.h>

static int slices = 16;

static int stacks = 16;

/* GLUT callback Handlers */

static void resize(int width, int height)

{

    const float ar = (float) width / (float) height;

    glViewport(0, 0, width, height);

    glMatrixMode(GL_PROJECTION);

    glLoadIdentity();

    ///glFrustum(-ar, ar, -1.0, 1.0, 2.0, 100.0);

    glOrtho(-ar*3, ar*3, -1*3, 1*3, -100, +100);

    glMatrixMode(GL_MODELVIEW);

    glLoadIdentity() ;

}

Step02-2

#ifdef __APPLE__

#include <GLUT/glut.h>

#else

#include <GL/glut.h>

#endif

#include <stdlib.h>

static int slices = 16;

static int stacks = 16;

/* GLUT callback Handlers */

static void resize(int width, int height)

{

    const float ar = (float) width / (float) height;

    glViewport(0, 0, width, height);

    glMatrixMode(GL_PROJECTION);///week15_step02-2 切換成投影矩陣(暫時

    glLoadIdentity();///week15_step02-2還原成單位矩陣(暫時

    ///glFrustum(-ar, ar, -1.0, 1.0, 2.0, 100.0);

    ///glOrtho(-ar*3, ar*3, -1*3, 1*3, -100, +100);

    gluPerspective(60, ar, 0.01, 1000);

///week15_step02-2角度,比例,近的,遠的

    glMatrixMode(GL_MODELVIEW);///week15_step02-2 切換成 Model view 矩陣

    glLoadIdentity() ;///week15_step02-2 還原成單位矩陣

}

Step02-3

建立GLUT專案   命名為week15-2_gluLookAt

///week15-2_gluLookAt

///函式reshape(), display()

#include <GL/glut.h>

void display()

{

    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);

    glutSolidTeapot(0.3);

    glutSwapBuffers();

}

void reshape(int w,int h)

{

    glViewport(0, 0, w, h);///視窗裡會看到的2D範圍

    float ar= w / (float) h;///aspect ratio長寬比

    glMatrixMode(GL_PROJECTION);///先切換到projection矩陣

    glLoadIdentity();///矩陣清空,成為單位矩陣(最一開始的矩陣)

    gluPerspective(60, ar, 0.01, 1000);

    glMatrixMode(GL_MODELVIEW);///做好後馬上切回modelview矩陣

    glLoadIdentity();///矩陣清空,成為單位矩陣(最一開始的矩陣)

    gluLookAt(0,0,1, 0,0,0, 0,1,0);

    ///在0,0,1 看著茶壺0,0,0, up是0,1,0

    glutPostRedisplay();

}

float eyeX = 0, eyeY = 0;

void motion(int x,int y)

{

    eyeX=(x-150.0)/150.0;

    eyeY=(150.0-y)/150.0;

    glMatrixMode(GL_MODELVIEW);///做好後馬上切回modelview矩陣

    glLoadIdentity();///矩陣清空,成為單位矩陣(最一開始的矩陣)

    gluLookAt(eyeX, eyeY, 1, 0,0,0, 0,1,0);

    glutPostRedisplay();

}

int main(int argc,char**argv)

{

    glutInit(&argc,argv);

    glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH);

glutCreateWindow("week15");

glutMotionFunc(motion);

glutDisplayFunc(display);

glutReshapeFunc(reshape);///名稱變reshape

glutMainLoop();

}