Week15

網址連結:https://jsyeh.org/3dcg10/

下載

data > data.zip

win32 > windows.zip

data.zip > windows\data(解壓後的data拉去windows資料夾下)

windows.zip > 下載 > windows\Projection.exe

glutLookAt()

eye從哪裡看

center看哪裡

eye center 決定攝影機的軸線，從eye射向center。攝影機照著軸線360度旋轉，由up向量決定。

fovy : field of view(y方向)視野的角度

aspect : aspect ratio 長寬比

安裝Git GitBash

-cd desktop

-git clone https://github.com/Owoyayou/2023graphicsa

-cd 2023graphicsa

-start .

開啟CodeBlocks

resize()裡的glFrustum()改成glOrtho()看看「透視投影」和「垂直投影」的差別

鍵盤+號

* GLUT Shapes Demo

* Written by Nigel Stewart November 2003

* This program is test harness for the sphere, cone

* and torus shapes in GLUT.

* Spinning wireframe and smooth shaded shapes are

* displayed until the ESC or q key is pressed. The

* number of geometry stacks and slices can be adjusted

* using the + and - keys.

#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切換成投影矩陣

glLoadIdentity();///還原成單位矩陣

//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);

///step02 角度,比例,近的,遠的

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

glLoadIdentity() ;///還原成單位矩陣

}

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 */

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");

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;

}

step02-4 增加motion函式

///week15-2_gluLookAt

///函式reshpae(),display()

#include <GL/glut.h>

void display(void)

{

glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

glutSolidTeapot(0.3);

glutSwapBuffers();

}

void reshape(int w,int h){

glViewport(0,0,w,h);///視窗裡看到2D範圍

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

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

glLoadIdentity();///矩陣清空，成為單位矩陣

gluPerspective(60,ar,0.01,1000);

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

glLoadIdentity();

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);

glLoadIdentity();

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);

glutMainLoop();

}

開啟Final_Project資料夾 > CodeBlocks開啟Final_Project.cbp