func readBuf(r io.Reader, n int) []byte {
		buf := make([]byte, n)
		_, err := io.ReadFull(r, buf)
		chk(err)
		return buf
	}

	func read8 (r io.Reader) uint8  { return readBuf(r, 1)[0] }
	func read16(r io.Reader) uint16 { return be.Uint16(readBuf(r, 2)) }
	func read32(r io.Reader) uint32 { return be.Uint32(readBuf(r, 4)) }
	func read64(r io.Reader) uint64 { return be.Uint64(readBuf(r, 8)) }

byte	*p = read8(r)
uint8	*p = read8(r)
uint16	*p = read16(r)
uint32	*p = read32(r)
uint64	*p = read64(r)

int8	*p = int8(read8(r))
int16	*p = int16(read16(r))
int32	*p = int32(read32(r))
int64	*p = int64(read64(r))

bool	switch n := read8(r); n {
	case 0:
		*p = false
	case 1:
		*p = true
	default:
		chk(fmt.Errorf("invalid bool: %d", n))
	}

float32	*p = math.Float32frombits(read32(r))
float64	*p = math.Float64frombits(read64(r))

AOMsg	{
		var err error
		*p, err = readAOMsg(r)
		chk(err)
	}

image/color.NRGBA	*p = color.NRGBA{A: read8(r), R: read8(r), G: read8(r), B: read8(r)}

map[uint16]*NodeMeta	{
		switch ver := read8(r); ver {
		case 0:
			*p = nil
		case 2:
			n := read16(r)
			*p = make(map[uint16]*NodeMeta, n)
			for ; n > 0; n-- {
				pos := read16(r)
				nm := new(NodeMeta)
				chk(deserialize(r, nm))
				(*p)[pos] = nm
			}
		default:
			chk(fmt.Errorf("unsupported nodemetas version: %d", ver))
		}
	}

map[[3]int16]*NodeMeta	{
		r, err := zlib.NewReader(byteReader{r})
		chk(err)

		switch ver := read8(r); ver {
		case 0:
			*p = nil
		case 2:
			n := read16(r)
			*p = make(map[[3]int16]*NodeMeta, n)
			for ; n > 0; n-- {
				var pos [3]int16
				for i := range pos {
					pos[i] = int16(read16(r))
				}
				nm := new(NodeMeta)
				chk(deserialize(r, nm))
				(*p)[pos] = nm
			}
		default:
			chk(fmt.Errorf("unsupported nodemetas version: %d", ver))
		}

		chk(r.Close())
	}

PointedThing	{
		var err error
		*p, err = readPointedThing(r)
		chk(err)
	}

[]AOMsg	{ // For AOInitData.Msgs.
		*p = make([]AOMsg, read8(r))
		for i := range *p {
			r := &io.LimitedReader{R: r, N: int64(read32(r))}
			msg, err := readAOMsg(r)
			chk(err)
			(*p)[i] = msg
			if r.N > 0 {
				chk(fmt.Errorf("%d bytes of trailing data", r.N))
			}
		}
	}

[]NodeDef	{ // For ToCltNodeDefs.Defs.
		*p = make([]NodeDef, read16(r))
		r := &io.LimitedReader{R: r, N: int64(read32(r))}
		for i := range *p {
			(*p)[i].Deserialize(r)
		}
		if r.N > 0 {
			chk(fmt.Errorf("%d bytes of trailing data", r.N))
		}
	}