電腦圖學week16

 ##Week16

##week16-0_sample

準備上課環境

0.freeglut,記得lib\libglut32.a

1.Opencv,記得 ADD PATH

2.重開 CodeBlocks, , Setting-Compiler 裡要改3個地方

-compiler 的include 要加入C:\OpenCV2.1\include
 -linker 的 lib要加入C:\OpenCV2.1\lib
 -linker 的設定，要加入cv210 cxcore210 highgui210

3.file-new-project,GLUT專案week16-0_sample

接下來要看課本程式

到https://jsyeh.org/3dcg10/下載 data win32 兩個都要解壓縮把data放進win32裡面

點開Projection.exe

##week16-1_sample_glutLOOKAT

1.file-new-project,GLUT專案week16-1_sample_glutLOOKAT

2.要改resize()函式，加上gluLookAt()函式就可以看著左上那個圓球

現在要做另一個修改，想要在按按鍵時看不同的地方

先把剛剛加的第39行註解掉，再到static void key 

if(key=='1')看左上方

if(key=='2')看上方

if(key=='3')看右上方

##week16-2_glutReshapeFunc_gluPerspective_gluLoojAt

請先看課本Projection.exe的範例

gluPerspective(視角，長寬比，z近，x遠)

fovy field of view in y 視角

aspect ratio 長寬比

我們將要寫個程式，11行+8行，做出透視投影

1.file-new-project,GLUT專案week16-2_glutReshapeFunc_gluPerspective_gluLoojAt

2.貼上11行程式碼

3.在int main()裡加入 glutReshapeFunc(reshape);

4.寫自己的 void reshape(int w,int h){....}

5.加入glutInitWindowSize(300,600);

##week16-3_myTexture_idi_id2_glBindTexture

1.file-new-project,GLUT專案week16-3_myTexture_idi_id2_glBindTexture

2.貼上week05_rotating_earth_main.cpp的程式碼

3.修改程式碼

#include <opencv/highgui.h> ///使用 OpenCV 2.1 比較簡單, 只要用 High GUI 即可

#include <opencv/cv.h>

#include <GL/glut.h>

GLUquadric * quad = NULL; ///todo: 要有一顆指標

int id1,id2;

int myTexture(char * filename)

{

    IplImage * img = cvLoadImage(filename); ///OpenCV讀圖

    cvCvtColor(img,img, CV_BGR2RGB); ///OpenCV轉色彩 (需要cv.h)

    glEnable(GL_TEXTURE_2D); ///1. 開啟貼圖功能

    GLuint id; ///準備一個 unsigned int 整數, 叫 貼圖ID

    glGenTextures(1, &id); /// 產生Generate 貼圖ID

    glBindTexture(GL_TEXTURE_2D, id); ///綁定bind 貼圖ID

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT); /// 貼圖參數, 超過包裝的範圖T, 就重覆貼圖

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT); /// 貼圖參數, 超過包裝的範圖S, 就重覆貼圖

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); /// 貼圖參數, 放大時的內插, 用最近點

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); /// 貼圖參數, 縮小時的內插, 用最近點

    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, img->width, img->height, 0, GL_RGB, GL_UNSIGNED_BYTE, img->imageData);

    return id;

}

///再貼上10行GLUT程式 (不要貼剛剛的程式)

float angle = 0;

void display()

{

    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);

    glEnable(GL_DEPTH_TEST);

    glBindTexture(GL_TEXTURE_2D, id2);

    glBegin(GL_POLYGON);

        glTexCoord2f(0,0); glVertex2f(-1,+1);

        glTexCoord2f(0,1); glVertex2f(-1,-1);

        glTexCoord2f(1,1); glVertex2f(+1,-1);

        glTexCoord2f(1,0); glVertex2f(+1,+1);

    glEnd();

    glBindTexture(GL_TEXTURE_2D, id1);

    glPushMatrix();

        glRotatef(90, 1, 0, 0);

        glRotatef(angle++, 0, 0, 1);

        gluSphere(quad, 0.5, 30, 30); ///glutSolidTeapot( 0.3 );

    glPopMatrix();

    glutSwapBuffers();

}

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

{

    glutInit(&argc, argv);

    glutInitDisplayMode(GLUT_DOUBLE|GLUT_DEPTH);

    glutInitWindowSize(500,500);

    glutCreateWindow("week05");

    glutIdleFunc(display);

    glutDisplayFunc(display);

    id2 = myTexture("C:/background.jpg");

    id1 = myTexture("c:/earth.jpg");

    quad = gluNewQuadric(); ///todo:把這顆指標,指好

    gluQuadricTexture(quad, 1);///todo: 做好地球的貼圖

    glutMainLoop();

}