Cid week15

 Step01

首先進入老師網站 https://jsyeh.org/3dcg10/ 下載[win32][source]檔案，並使用7-zip解壓縮至windows，並把data解壓縮至windows資料夾內，

解壓縮結束後，執行Projection.exe看看相機對視角的影響

安裝git,開 Git Bash

cd desktop          進入桌面

git clone http://github.com/.../2023graphicsb

cd 2023graphics 進入倉庫目錄

start .                 開檔案總管

下載自己的檔案，並解壓縮後開啟Codeblocks，開新glut專案week15_glutLookAt，檔案存放於自己倉庫，設定Final檔案內的Freeglut。

利用程式碼改變視角的位子

程式碼

增加的程式碼

#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);

    glLoadIdentity();

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

    glMatrixMode(GL_MODELVIEW);

    glLoadIdentity() ;

}

static void display(void)

{

    const double t = glutGet(GLUT_ELAPSED_TIME) / 1000.0;

    const double a = t*90.0;

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glColor3d(1,0,0);

    glPushMatrix();

        glTranslated(-2.4,1.2,-6);

        glRotated(60,1,0,0);

        glRotated(a,0,0,1);

        glutSolidSphere(1,slices,stacks);

    glPopMatrix();

    glPushMatrix();

        glTranslated(0,1.2,-6);

        glRotated(60,1,0,0);

        glRotated(a,0,0,1);

        glutSolidCone(1,1,slices,stacks);

    glPopMatrix();

    glPushMatrix();

        glTranslated(2.4,1.2,-6);

        glRotated(60,1,0,0);

        glRotated(a,0,0,1);

        glutSolidTorus(0.2,0.8,slices,stacks);

    glPopMatrix();

    glPushMatrix();

        glTranslated(-2.4,-1.2,-6);

        glRotated(60,1,0,0);

        glRotated(a,0,0,1);

        glutWireSphere(1,slices,stacks);

    glPopMatrix();

    glPushMatrix();

        glTranslated(0,-1.2,-6);

        glRotated(60,1,0,0);

        glRotated(a,0,0,1);

        glutWireCone(1,1,slices,stacks);

    glPopMatrix();

    glPushMatrix();

        glTranslated(2.4,-1.2,-6);

        glRotated(60,1,0,0);

        glRotated(a,0,0,1);

        glutWireTorus(0.2,0.8,slices,stacks);

    glPopMatrix();

    glutSwapBuffers();

}

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

{

    switch (key)

    {

        case 27 :

        case 'q':

            exit(0);

            break;

        case '+':

            slices++;

            stacks++;

            break;

        case '-':

            if (slices>3 && stacks>3)

            {

                slices--;

                stacks--;

            }

            break;

    }

    glutPostRedisplay();

}

static void idle(void)

{

    glutPostRedisplay();

}

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 };

/* Program entry point */

float eyeX = 0,eyeY = 0;

void motion(int x, int y){

    eyeX=3*(x-320)/320.0;

    eyeY=3*(240-y)/240.0;

    glLoadIdentity();

    gluLookAt(eyeX, eyeY,-3,  0, 0, -6,  0, 1, 0);

    glutPostRedisplay();

}

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

{

    glutInit(&argc, argv);

    glutInitWindowSize(640,480);

    glutInitWindowPosition(10,10);

    glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);

    glutCreateWindow("GLUT Shapes");

    glutMotionFunc(motion);

    glutReshapeFunc(resize);

    glutDisplayFunc(display);

    glutKeyboardFunc(key);

    glutIdleFunc(idle);

    glClearColor(1,1,1,1);

    glEnable(GL_CULL_FACE);

    glCullFace(GL_BACK);

    glEnable(GL_DEPTH_TEST);

    glDepthFunc(GL_LESS);

    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);

    glutMainLoop();

    return EXIT_SUCCESS;

}

Step02-1

體會看看垂直投影glOrtho(),，透視投glFrustum()gluPerspeotive(),影的差別,其中glOrtho()為預設投影,glFrustum()會變成角度張開的感覺,gluPerspeotive()的參數比較容易設定

gluPerspective()

glOrtho()

glFrustum()

Step02-2

換成glOrtho透視參數*3倍前

glOrtho(-ar, ar, -1.0, 1.0, 2.0, 100.0);

換成glOrtho透視參數*3倍後

glOrtho(-ar*3, ar*3, -1.0*3, 1.0*3, 2.0, 100.0);

換成gluPerspective透視

gluPerspective(60, ar, 0.01, 1000);

將檔案被分到Girhub

Step03-1

透視茶壺

程式碼

#include <GL/glut.h>

void display(){

        glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);

        glutSolidTeapot(0.3);

        glutSwapBuffers();

}

void motion (int x, int y){

    glLoadIdentity();

    float eyeX =(x-150)/150.0, eyeY = (150-y)/150.0;

    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);

    glutMainLoop();

}

Step03-2

程式碼

#include <GL/glut.h>

void display(){

        glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);

        glutSolidTeapot(0.3);

        glutSwapBuffers();

}

void motion (int x, int y){

    glLoadIdentity();

    float eyeX =(x-150)/150.0, eyeY = (150-y)/150.0;

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

    glutPostRedisplay();

}

void reshape(int w, int h){

    float ar = w / (float) h;

    glViewport(0, 0, w, h);

    glMatrixMode(GL_PROJECTION);

    glLoadIdentity();

    gluPerspective(60, ar, 0.01, 1000);

    glMatrixMode(GL_MODELVIEW);

    glLoadIdentity();

    gluLookAt(0,0,1, 0,0,0, 0,1,0);

}

int main(int argc, char** argv)

{

    glutInit(&argc,argv);

    glutInitDisplayMode(GLUT_DOUBLE|GLUT_DEPTH);

    glutCreateWindow("week15");

    glutReshapeFunc(reshape);

    glutMotionFunc(motion);

    glutDisplayFunc(display);

    glutMainLoop();

}

Step03-3

期末關節調整，換成陣列

程式碼

#include <stdio.h>

#include <GL/glut.h>

#include "glm.h"

GLMmodel * head = NULL;

GLMmodel * body = NULL;

GLMmodel * uparmR = NULL;

GLMmodel * lowarmR = NULL;

int show[4] = {1,1,1,1};

int ID = 3;

float teapotX = 0, teapotY = 0;

float angle[20] ={};

///float angle = 0;

FILE * fout = NULL;

FILE * fin = NULL;

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

    if(key=='0') ID = 0;

    if(key=='1') ID = 1;

    if(key=='2') ID = 2;

    if(key=='3') ID = 3;

    glutPostRedisplay();

}

void display()

{

    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);

    if(head==NULL){

        head = glmReadOBJ("model/head.obj");

        body = glmReadOBJ("model/body.obj");

        uparmR = glmReadOBJ("model/uparmR.obj");

        lowarmR = glmReadOBJ("model/lowarmR.obj");

    }

    glPushMatrix();

        glScalef(0.3, 0.3, 0.3);

        glPushMatrix();

            ///glTranslatef(teapotX, teapotY, 0);

            if(ID==0) glColor3f(1,0,0);

            else glColor3f(1,1,1);

            if(show[0]) glmDraw(head, GLM_MATERIAL);

        glPopMatrix();

        if(ID==1) glColor3f(1,0,0);

        else glColor3f(1,1,1);

        if(show[1]) glmDraw(body, GLM_MATERIAL);

        glPushMatrix();

            ///glTranslatef(teapotX, teapotY, 0);

            glTranslatef(-1.360000, +0.360000, 0);

            glRotatef(angle[2], 0, 0, 1);

            glTranslatef(1.360000, -0.360000, 0);

            if(ID==2) glColor3f(1,0,0);

            else glColor3f(1,1,1);

            if(show[2]) glmDraw(uparmR, GLM_MATERIAL);

            glPushMatrix();

                ///glTranslatef(teapotX, teapotY, 0);

                glTranslatef(-1.959999, +0.080000, 0);

                glRotatef(angle[3], 0, 0, 1);

                glTranslatef(1.959999, -0.080000, 0);

                if(ID==3) glColor3f(1,0,0);

                else glColor3f(1,1,1);

                if(show[3]) glmDraw(lowarmR, GLM_MATERIAL);

            glPopMatrix();

        glPopMatrix();

    glPopMatrix();

    glColor3f(0,1,0);

    glutSolidTeapot( 0.02 );

    glutSwapBuffers();

}

int oldX=0, oldY=0;

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

    if(state==GLUT_DOWN){

        oldX = x;

        oldY = y;

    }

}

void motion(int x, int y) {

    teapotX += (x - oldX)/150.0*3;

    teapotY -= (y - oldY)/150.0*3;

    printf("glTranslatef(%f, %f, 0);\n", teapotX, teapotY);

    angle[ID] += x-oldX;

    oldX = x;

    oldY = y;

    glutPostRedisplay();

}

int main(int argc, char** argv)

{

    glutInit(&argc, argv);

    glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH);

    glutCreateWindow("week14");

    glutMotionFunc(motion);

    glutDisplayFunc(display);

    glutKeyboardFunc(keyboard);

    glutMouseFunc(mouse);

    glutMainLoop();

}