图形学光照实验报告.docx

计算机 学院 专业 班 学号 姓名 协作者 无 教师评定 实验三OpenGL 交互式控制及简单光照明模型1、实验目的与要求1. 通过实验掌握OpenGL 中的交互式控制；2. 通过实验掌握例子intercontrol.c，并验证OpenGL 交互式控制方法；3. 通过实验设计修改例子intercontrol.c 的参数，分别达到以下要求：(1)按下键盘上的”V”键，三角形就沿着45 度角向上平移4.0f 距离；(2) 按下键盘上的”B”键，三角形就沿着45 度角向下平移4.0f 距离；4. 通过实验掌握例子slight.c，并验证OpenGL 简单光照明模型；2、实验方案请描述为达到实验的需要完成哪些方面的实验，列举出实验的基本要点和重点。实验：OpenGL 简单光照明模型,设计一个球体模型，产生光照效果。3、实验结果和数据处理实验：OpenGL 简单光照明模型#include #include #include #include struct Vector float fx, fy, fz;struct Color float Ir, Ig, Ib;float KaIa;/环境光强度float Kd, n;Vector H,light;Color mLight, mColor;GLboolean bLight = false;/利用圆的八向对称性生成圆上的点void CirclePt(int x0, int y0, int x, int y, Color mColor) glColor3ub (mColor.Ir, mColor.Ig, mColor.Ib); glBegin(GL_POINTS); glVertex2i ( x+x0, y+y0);/x,y glVertex2i ( -x+x0, y+y0);/-x,y glVertex2i ( x+x0, -y+y0);/x, -y glVertex2i ( -x+x0, -y+y0);/-x, -y glVertex2i ( y+x0, x+y0);/y, x glVertex2i ( y+x0, -x+y0);/y, -x glVertex2i ( -y+x0, x+y0);/-y, x glVertex2i ( -y+x0,-x+y0);/-y, -x glEnd();/中点圆生成算法void MidCircle(int x0, int y0, int r, Color mColor) int x,y,deltax,deltay,d; x = 0; y = r; deltax = 3; deltay = 5-r-r; d = 1-r; CirclePt( x0, y0, x, y, mColor); while(xy) if(d0) d += deltax; deltax += 2; deltay += 2; x+; else d += deltay; deltax += 2; deltay += 4; x+; y-; CirclePt( x0, y0, x, y, mColor); /根据中点圆算法填充圆域void FlatCircle(int x0, int y0, int r, Color mColor) int x,y,deltax,deltay,d; x = 0; y = r; deltax = 3; deltay = 5-r-r; d = 1-r; glColor3ub (mColor.Ir, mColor.Ig, mColor.Ib); glBegin(GL_POINTS); for(int i=-x;i=x;i+) glVertex2i (i+x0,y+y0); glVertex2i (i+x0,-y+y0); for(i=-y;i=y;i+) glVertex2i (i+x0,x+y0); glVertex2i (i+x0,-x+y0); while(xy) if(d0) d += deltax; deltax += 2; deltay += 2; x+; else d += deltay; deltax += 2; deltay += 4; x+; y-; for(i=-x;i=x;i+) glVertex2i (i+x0,y+y0); glVertex2i (i+x0,-y+y0); for(i=-y;i=y;i+) glVertex2i (i+x0,x+y0); glVertex2i (i+x0,-x+y0); glEnd();/初始化设定void Init() float mo; Vector eye; mLight.Ir = 0; mLight.Ig = 175; mLight.Ib = 0; KaIa=80; Kd = 1; n = 10; light.fx=0.50;light.fy=0.50; light.fz = sqrt(1-(light.fx*light.fx)-(light.fy*light.fy); eye.fx=0;eye.fy=0;eye.fz=1; H.fx=light.fx+eye.fx; H.fy=light.fy+eye.fy; H.fz=light.fz+eye.fz; mo=sqrt(H.fx*H.fx+H.fy*H.fy+H.fz*H.fz); H.fx=(H.fx/mo);H.fy=(H.fy/mo);H.fz=(H.fz/mo); H.fx=(H.fx/mo);H.fy=(H.fy/mo);H.fz=(H.fz/mo); glClearColor(0.0, 0.0, 0.0, 0.0); glShadeModel(GL_SMOOTH);/根据Phong模型计算光强Color Phong(int x0, int y0, int r, int x, int y) Vector N; float z,alpha,theta,Ks; Ks=1.0-Kd; z=sqrt(float)(r*r-(x-x0)*(x-x0)-(y-y0)*(y-y0); N.fx=(x-x0)*1.0/r; N.fy=(y-y0)*1.0/r; N.fz = z*1.0/r; theta = N.fx * light.fx + N.fy * light.fy + N.fz * light.fz; if(theta0) theta=0; alpha=H.fx*N.fx+H.fy*N.fy+H.fx*N.fz; if(alpha0) alpha=0; mColor.Ir=KaIa+mLight.Ir*Kd*theta+mLight.Ir*Ks*pow(alpha,n); mColor.Ig=KaIa+mLight.Ig*Kd*theta+mLight.Ig*Ks*pow(alpha,n); mColor.Ib=KaIa+mLight.Ib*Kd*theta+mLight.Ib*Ks*pow(alpha,n); return mColor;/根据计算的光强按球体的结果着色void Sphere(int x0, int y0, int r) int x,y,deltax,deltay,d; x = 0; y = r; deltax = 3; deltay = 5-r-r; d = 1-r; glBegin(GL_POINTS); for(int i=-x;i=x;i+) mColor=Phong(x0,y0,r,i+x0,y+y0); glColor3ub (mColor.Ir, mColor.Ig, mColor.Ib); glVertex2i (i+x0,y+y0); glColor3ub (mColor.Ir, mColor.Ig, mColor.Ib); glVertex2i (i+x0,-y+y0); for(i=-y;i=y;i+) mColor=Phong(x0,y0,r,i+x0,x+y0); glColor3ub (mColor.Ir, mColor.Ig, mColor.Ib); glVertex2i (i+x0,x+y0); glColor3ub (mColor.Ir, mColor.Ig, mColor.Ib); glVertex2i (i+x0,-x+y0); while(xy) if(d0) d += deltax; deltax += 2; deltay += 2; x+; else d += deltay; deltax += 2; deltay += 4; x+; y-; for(i=-x;i=x;i+) mColor=Phong(x0,y0,r,i+x0,y+y0); glColor3ub (mColor.Ir, mColor.Ig, mColor.Ib); glVertex2i (i+x0,y+y0); glColor3ub (mColor.Ir, mColor.Ig, mColor.Ib); glVertex2i (i+x0,-y+y0); for(i=-y;i=y;i+) mColor=Phong(x0,y0,r,i+x0,x+y0); glColor3ub (mColor.Ir, mColor.Ig, mColor.Ib); glVertex2i (i+x0,x+y0); glColor3ub (mColor.Ir, mColor.Ig, mColor.Ib); glVertex2i (i+x0,-x+y0); glEnd();void myDisplay() glClear(GL_COLOR_BUFFER_BIT); glColor3f (1.0f, 1.0f, 1.0f); Color clr; clr.Ir = 180, clr.Ig = 180, clr.Ib = 180; MidCircle(80, 240, 70, clr); FlatCircle(280, 240, 70, clr); Sphere(540, 240, 70); glFlush();void Reshape(int w, int h) glViewport(0, 0, (GLsizei) w, (GLsizei) h); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluOrtho2D(0.0, (GLdouble) w, 0.0, (GLdouble) h);int main(int argc, char *argv) glutInit(&argc, argv);