北方工业大学 计算机图形学实验 几何变换.doc

计算机图形学实验报告02北方工业大学 计算机图形学课程实验报告题 目：实验二 几何变换学 院：专 业：指导教师：学生班级：学生学号：学生姓名：教师评定：8学号：班级：姓名：实验报告二 几何变换实验一实验目的1熟悉OpenGL图形库；2掌握几何变换算法。二实验环境1软件环境：操作系统：Win7应用软件：VC6.0，OpenGL2硬件环境CPU:显卡：三用矩阵计算实现二维几何变换写程序实现基本矩阵运算，同时实现平移、放缩、旋转等几何变换。要求自己设计实例验证平移、放缩、旋转函数，采用键盘交互。已给出二维点坐标结构体、单位矩阵赋值函数。已给出：二维点坐标结构体struct Point2Dfloat x, y;已给出：宏定义33数组typedef float Matrix3x3 33;Matrix3x3 matComposite; 已给出：单位矩阵赋值函数void matrix3x3SetIdentity(Matrix3x3 matIdent3x3)int row, col;for(row=0; row3;row+)for(col=0; col3; col+)matIdent3x3rowcol = (row=col);要求给出以下函数及实例截图。1矩阵左乘运算函数Void matrix3x3PreMultiply(Matrix3x3 m1, Matrix3x3 m2)int row, col;Matrix3x3 temp;for(row=0; row3;row+)for(col=0; col3; col+)temprowcol = m1row0*m20col + m1row1*m21col + m1row2*m22col;for(row=0; row3;row+)for(col=0; col3; col+)m2rowcol=temprowcol;2平移函数void Translate2D (float tx, float ty) Matrix3x3 matTransl;matrix3x3SetIdentity (matTransl);matTransl02=tx;matTransl12=ty;matrix3x3PreMultiply(matTransl,matComposite); 3顶点矩阵左乘合成函数void TransformVerts2D(int nVerts,Point2D * verts) GLint k;GLfloat temp1, temp2;for (k=0;knVerts; k+)temp1=matComposite 00*vertsk.x + matComposite 01*vertsk.y + matComposite 02;temp2=matComposite 10*vertsk.x + matComposite 11*vertsk.y+matComposite 12;vertsk.x=temp1;vertsk.y=temp2; 4绘制三角形函数void RenderTriangle (Point2D* verts) int k;glBegin (GL_TRIANGLES);for (k=0;k3;k+)glVertex2f(vertsk.x,vertsk.y);glEnd(); 5旋转函数void Rotate2D (Point2D fixedPt, float theta) Matrix3x3 matRot; matrix3x3SetIdentity (matRot); matRot 00=cos(theta); matRot 01=-sin (theta); matRot 02=fixedPt.x*(1-cos (theta)+fixedPt.y*sin(theta); matRot 10=sin (theta); matRot 11=cos (theta); matRot 312=fixedPt.x*(1-cos (theta)-fixedPt.y*sin(theta); matrix3x3PreMultiply(matRot,matComposite); 6缩放函数void scale2D (GLfloat sx,GLfloat sy,wcPt2D fixedPt) Matrix3x3 matScale; matrix3x3SetIdentity(matScale); matScale 00=sx; matScale 02=(1-sx)*fixedPt.x; matScale 11=sy; matScale 12=(1-sy)*fixedPt.y;matrix3x3PreMultiply(matScale,matComposite); 7平移实例及截图8旋转实例及截图9缩放实例及截图四用OpenGL函数库实现几何图元旋转特效在Nehe教程Lesson04基础上，修改程序，在屏幕上画两个三角形、两个四边形，并完成相应动画效果，三角形A绕X轴旋转，三角形B绕Y轴旋转，四边形C绕Z轴旋转，四边形D绕X轴旋转。要求给出RenderScene函数及实例截图。int DrawGLScene(GLvoid)glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);glLoadIdentity();glTranslatef(-1.5f,0.0f,-6.0f);glRotatef(rtri1,1.0f,0.0f,0.0f);glBegin(GL_TRIANGLES);glColor3f(1.0f,0.0f,0.0f);glVertex3f( 0.0f, 1.0f, 0.0f);glColor3f(1.0f,0.0f,0.0f);glVertex3f(-1.0f,-1.0f, 0.0f);glColor3f(1.0f,0.0f,0.0f);glVertex3f( 1.0f,-1.0f, 0.0f);glEnd();glLoadIdentity();glTranslatef(-4.5f,0.0f,-6.0f);glRotatef(rtri2,0.0f,1.0f,0.0f);glBegin(GL_TRIANGLES);glColor3f(1.0f,0.0f,0.0f);glVertex3f( 0.0f, 1.0f, 0.0f);glColor3f(1.0f,0.0f,0.0f);glVertex3f(-1.0f,-1.0f, 0.0f);glColor3f(1.0f,0.0f,0.0f);glVertex3f( 1.0f,-1.0f, 0.0f);glEnd();glLoadIdentity();glTranslatef(1.5f,0.0f,-6.0f);glRotatef(rquad1,1.0f,0.0f,0.0f);glColor3f(1.0f,0.5f,1.0f);glBegin(GL_QUADS);glVertex3f(-1.0f, 1.0f, 0.0f);glVertex3f( 1.0f, 1.0f, 0.0f);glVertex3f( 1.0f,-1.0f, 0.0f);glVertex3f(-1.0f,-1.0f, 0.0f);glEnd();glLoadIdentity();glTranslatef(4.5f,0.0f,-6.0f);glRotatef(rquad2,0.0f,0.0f,1.0f);glColor3f(1.0f,0.5f,1.0f);glBegin(GL_QUADS);glVertex3f(-1.0f, 1.0f, 0.0f);g