[作業四 擬真3D空間場景-元智校園]

主題介紹 - 海洋動物園

       在廣闊的校園中，可愛的小豬、聰明伶俐的海豚與驕傲的老鷹活動於元智校園之中，校園的周圍禁是一望無

際的海洋，給人廣闊無邊的感覺。



程式設計與寫作方法、執行結果呈現

         這次的程式主要的重點就是學會如何讀取OBJ

首先，就是要先畫出3D模型，利用Audodesk 的 3ds Max 就可以設計出不錯的模型

再來，利用glm所提供的函式就可以成功的讀取OBJ。

程式代碼大致如下：

{

    GLMmodel *glm_model_pig;

     glm_model_pig= glmReadOBJ( "model/pig.obj" );

     glmUnitize( glm_model_pig );

     glmScale( glm_model_pig, 5 );

     glmFacetNormals( glm_model_pig );

     glmVertexNormals( glm_model_pig, 90 );

     list_id[0] = glmList( glm_model_pig, GLM_MATERIAL | GLM_SMOOTH );

     glmDelete( glm_model_pig );

}

如此就可以將OBJ成功的讀入程式中

再利用glCallList繪出

    glPushMatrix();

glDisable(GL_TEXTURE_2D);

glTranslatef(-5.0f,-5.0f,-20.0f);

    glCallList( list_id[0] );

glPopMatrix();

此外，我在這次的程式還加入的skybox，這個要實作也不困難，

首先一樣利用glm讀入bmp檔，然後再利用texture貼圖

程式碼大致上如下

首先是讀取bmp檔

bool Load_Texture(unsigned int & aTexture, char * fileName) {

if(!fileName) return false; //if no file name is given return

FILE *aFile = NULL;

AUX_RGBImageRec *image_record = NULL;

if((aFile = fopen(fileName, "rb")) == NULL) return false;

WCHAR wsz[64];

swprintf(wsz, L"%S", fileName);

LPCWSTR p = wsz;

image_record = auxDIBImageLoad(p); //Function to load BMP

if(!image_record) return false; //check that BMP loaded

glGenTextures(1, &aTexture); //generates 1 texture name

glPixelStorei (GL_UNPACK_ALIGNMENT, 1); //sets how the pixels of the texture are stored

glBindTexture(GL_TEXTURE_2D, aTexture); //binds the name to the target

//build prefiltered textures at different resolutions

gluBuild2DMipmaps(GL_TEXTURE_2D, 3, image_record->sizeX, 

 image_record->sizeY, GL_RGB, GL_UNSIGNED_BYTE, image_record->data);

//give the texture its attributes

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST);

glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);

// Now we need to free the image data that we loaded since openGL stored it as a texture

if (image_record) { //if we stored data then free the memory

if (image_record->data) { //check if there is any data

// free(image_record->data); //free the memory

}

// free(image_record); //free the image record

}

return true; //everything should have worked so return true

}

然後再設置Texture

void skyboxInit() 

{

Load_Texture(texture[0],"texture/left.bmp");

Load_Texture(texture[1],"texture/front.bmp");

Load_Texture(texture[2],"texture/right.bmp");

Load_Texture(texture[3],"texture/back.bmp");

Load_Texture(texture[4],"texture/down.bmp");

Load_Texture(texture[5],"texture/up.bmp");

}

然後再呼叫繪出

void skybox()

{

glPushMatrix();

glDisable (GL_LIGHTING);

glColor3f(1.0f,1.0f,1.0f);

glEnable(GL_TEXTURE_2D);

glBindTexture(GL_TEXTURE_2D, texture[0]);

glBegin (GL_QUADS);

glNormal3d (0.0,0.0,1.0); glTexCoord2d (0.0 ,0.0 );

                glVertex3d (-100.0,-10.0,100.0);

                

glNormal3d (0.0,0.0,1.0); glTexCoord2d (1.0 ,0.0 );

                glVertex3d (-100.0,-10.0,-100.0);

                

                glNormal3d (0.0,0.0,1.0);

glTexCoord2d (1.0 ,1.0 );

                glVertex3d (-100.0,100.0,-100.0);

glTexCoord2d (0.0 ,1.0 );

                glVertex3d (-100.0,100.0,100.0);

glEnd ();

glBindTexture(GL_TEXTURE_2D, texture[1]);

glBegin (GL_QUADS);

glNormal3d (0.0,0.0,1.0); glTexCoord2d (0.0 ,0.0 );

                glVertex3d (-100.0,-10.0,100.0);

                

glNormal3d (0.0,0.0,1.0); glTexCoord2d (1.0 ,0.0 );

                glVertex3d (100.0,-10.0,100.0);

                

                glNormal3d (0.0,0.0,1.0);

glTexCoord2d (1.0 ,1.0 );

                glVertex3d (100.0,100.0,100.0);

glTexCoord2d (0.0 ,1.0 );

                glVertex3d (-100.0,100.0,100.0);

glEnd ();

glBindTexture(GL_TEXTURE_2D, texture[3]);

glBegin (GL_QUADS);

glNormal3d (0.0,0.0,1.0); glTexCoord2d (0.0 ,0.0 );

                glVertex3d (-100.0,-10.0,-100.0);

                

glNormal3d (0.0,0.0,1.0); glTexCoord2d (1.0 ,0.0 );

                glVertex3d (100.0,-10.0,-100.0);

                

                glNormal3d (0.0,0.0,1.0);

glTexCoord2d (1.0 ,1.0 );

                glVertex3d (100.0,100.0,-100.0);

glTexCoord2d (0.0 ,1.0 );

                glVertex3d (-100.0,100.0,-100.0);

glEnd ();

glBindTexture(GL_TEXTURE_2D, texture[3]);

glBegin (GL_QUADS);

glNormal3d (0.0,0.0,1.0); glTexCoord2d (0.0 ,0.0 );

                glVertex3d (100.0,-10.0,100.0);

                

glNormal3d (0.0,0.0,1.0); glTexCoord2d (1.0 ,0.0 );

                glVertex3d (100.0,-10.0,-100.0);

                

                glNormal3d (0.0,0.0,1.0);

glTexCoord2d (1.0 ,1.0 );

                glVertex3d (100.0,100.0,-100.0);

glTexCoord2d (0.0 ,1.0 );

                glVertex3d (100.0,100.0,100.0);

glEnd ();

glPopMatrix();

}

如此一來就可以做出不錯的3D立體空間

         一樣附上作品影片

  
心得與討論


        作業四讀入OBJ檔後又加入的天空盒的texture，讓整個程式空間都完整了。

不過在讀取texture的時候，有一些型態的轉換要注意，例如"LPCWSTR"，