billboarding by JazzD

void DrawBillboard(float x , float y , float z,float scale, GLuint texture) {     float mat[16];     float size = scale;     glGetFloatv(GL_MODELVIEW_MATRIX, mat);     CVector3 pos(x,y,z);     CVector3 right(mat[0],mat[4], mat[8]);     CVector3 up(mat[1],mat[5],mat[9]);     glBindTexture(GL_TEXTURE_2D, texture);     CVector3 blc((pos + ( right + up ) * -size));     CVector3 brc((pos + ( right - up ) * size));     CVector3 trc((pos + ( right + up ) * size));     CVector3 tlc((pos + ( right - up ) * -size));     glBegin(GL_QUADS);         glTexCoord2f(0.0f,0.0f); glVertex3f(blc.x,blc.y,blc.z);         glTexCoord2f(1.0f,0.0f); glVertex3f(brc.x,brc.y,brc.z);         glTexCoord2f(1.0f,1.0f); glVertex3f(trc.x,trc.y,trc.z);         glTexCoord2f(0.0f,1.0f); glVertex3f(tlc.x,tlc.y,tlc.z);     glEnd(); }