Week08 呆江的筆記

第八周重點：打光

程式碼：

新增標頭  #include "glm.h" ///使用glm.h外掛

GLMmodel *pmodel = NULL;  /// 宣告一個指標指向NULL

在display()內

範例1：畫出選轉茶壺
    glPushMatrix();
        glTranslated(-2.4,1.2,-6);
        glRotated(60,1,0,0);
        glRotated(a,0,0,1);
        glutSolidTeapot(0.8);
    glPopMatrix();

範例2：讀取3D模型

glPushMatrix();

        glTranslated(0,1.2,-6);

        glRotated(60,1,0,0);

        glRotated(a,0,0,1);

         if (!pmodel) {

        pmodel = glmReadOBJ("data/porsche.obj");

        if (!pmodel) exit(0);

        glmUnitize(pmodel);

        glmFacetNormals(pmodel);

        glmVertexNormals(pmodel, 90.0);

        }

        glmDraw(pmodel, GLM_SMOOTH | GLM_MATERIAL);

    glPopMatrix();

其餘使用範例程式碼

執行結果：

自己寫出用滑鼠移動的車(打光)：
#include "glm.h"

GLMmodel *pmodel = NULL;
float angle = 0; 
void motion(int x,int y){  ///新增motion()
    angle = x;
    glutPostRedisplay();
}
void display(void)
{
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glPushMatrix();
        glRotatef(angle,0,1,0);  ///旋轉 (要記得!!) 
         if (!pmodel) {
        pmodel = glmReadOBJ("data/porsche.obj");
        if (!pmodel) exit(0);
        glmUnitize(pmodel);
        glmFacetNormals(pmodel);
        glmVertexNormals(pmodel, 90.0);
        }

        glmDraw(pmodel, GLM_SMOOTH | GLM_MATERIAL);
    glPopMatrix();
    glutSwapBuffers();
}

///打光用
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 };

int main(int argc, char *argv[])
{
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);

    glutCreateWindow("GLUT Shapes");

    glutDisplayFunc(display);
    glutMotionFunc(motion);
    glClearColor(1,1,1,1);

    glEnable(GL_DEPTH_TEST);
    glDepthFunc(GL_LESS);

    glEnable(GL_LIGHT0); ///打開LIGHT0
    glEnable(GL_NORMALIZE); ///打開法向量
    glEnable(GL_COLOR_MATERIAL); ///打開下面的 glLight 和 glMaterial
    glEnable(GL_LIGHTING);

///對應上面打光用
    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;
}

執行結果: