void sh_rect::rotate(float angle) {
angle *= torad;
mat2x2 rot = mat2x2( cos(angle), -sin(angle),
sin(angle), cos(angle) );
vec2 cur_cen = _center;
move_position(-_center.x, -_center.y);
_position = _position*rot;
for(int i = 0; i < 6; i++) {
data[i] = data[i]*rot;
}
move_position(cur_cen);
_left = (_position.x - _width/2.0f);
_right = (_position.x + _width/2.0f);
_top = (_position.y + _height/2.0f);
_bottom = (_position.y - _height/2.0f);
// _rotation = _rotation*rot;
glBindBuffer(GL_ARRAY_BUFFER, _vbo);
glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(data), data);
}
mat2x2 inline operator*(mat2x2 &l, mat2x2 &r) {
return mat2x2((l.a*r.a%mod+l.b*r.c%mod)%mod, (l.a*r.b%mod+l.b*r.d%mod)%mod,
(l.a*r.c%mod+l.c*r.d%mod)%mod, (l.c*r.b%mod+l.d*r.d%mod)%mod);
}
