this float decode has to be wrong

ent/dict.go

@@ -75,7 +75,7 @@ func (d *Dict) createEntity(id int) error {
 	Debug.Printf("create entity id: %d classId: %d className: %v class: %v\n", id, classId, className, class)
 	e := class.New(serial)
 	d.entities[id] = e
-	return fillSlots(e, d.sr, d.br)
+	return fillSlots(e, class.Name.String(), d.sr, d.br)
 }
 
 func (d *Dict) getEntity(id int) *Entity {
@@ -200,7 +200,7 @@ func (d *Dict) syncBaselines() {
 
 		d.br.SetSource(e.Value)
 		Debug.Printf("syncBaselines has new baseline for class %v", c)
-		if err := fillSlots(c.baseline, d.sr, d.br); err != nil {
+		if err := fillSlots(c.baseline, c.Name.String(), d.sr, d.br); err != nil {
 			Debug.Printf("syncBaselines failed to fill a baseline: %v", err)
 			continue
 		}

ent/entity.go

@@ -6,6 +6,8 @@ type Entity struct {
 	slots  []interface{}
 }
 
-func (e *Entity) getSlotValue(n int) interface{}    { return e.slots[n] }
+func (e *Entity) slotName(n int) string             { return e.Class.Fields[n].name.String() }
+func (e *Entity) slotType(n int) string             { return e.Class.Fields[n]._type.String() }
+func (e *Entity) slotValue(n int) interface{}       { return e.slots[n] }
+func (e *Entity) slotDecoder(n int) decoder         { return e.Class.Fields[n].decoder }
 func (e *Entity) setSlotValue(n int, v interface{}) { e.slots[n] = v }
-func (e *Entity) getSlotDecoder(n int) decoder      { return e.Class.Fields[n].decoder }

ent/field.go

@@ -14,7 +14,7 @@ type Field struct {
 	bits              uint    // number of bits used to encode field?
 	low               float32 // lower limit of field values
 	high              float32 // upper limit of field values
-	flags             int     // dunno what these flags do
+	flags             int     // used by float decoder
 	serializer        *Symbol // class on which the field was defined
 	serializerVersion *int32  // version of the class on which the field was defined
 	class             *Class  // source class on which the field was originally defined

ent/float_decoders.go

@@ -7,10 +7,9 @@ import (
 )
 
 const (
-	f_round_down = 1 << iota
-	f_round_up
-	f_encode_zero
-	f_encode_ints
+	f_min = 1 << iota
+	f_max
+	f_center
 )
 
 func floatDecoder(f *Field) decoder {
@@ -24,13 +23,22 @@ func floatDecoder(f *Field) decoder {
 		panic("quantization rules make no sense")
 	}
 
+	bits := f.bits
+	low := f.low
+	high := f.high
+
 	flags := f.flags
 
+	// there's a flag that's -8 and i don't know what to do with it. I'm just
+	// gonna mask away everything except the three least significant bits and
+	// pray for the best.
+	flags = flags & 7
+
 	// number of input steps
-	// steps := int(1<<f.bits - 1)
+	steps := int(1<<f.bits - 1)
 
 	// keep the inverse to mult instead of divide later
-	// inv_steps := 1.0 / float32(steps)
+	inv_steps := 1.0 / float32(steps)
 
 	// total range of values
 	span := f.high - f.low
@@ -39,27 +47,36 @@ func floatDecoder(f *Field) decoder {
 		panic("quantization span is backwards")
 	}
 
-	if flags&f_round_down&f_round_up > 0 {
-		panic("how can you round down and up at the same time")
-	}
-
 	// output width of each step
-	// step_width := span * inv_steps
+	step_width := span * inv_steps
 
-	return func(br bit.Reader) interface{} {
-		if flags&f_round_down > 0 {
-			return nil
+	var special *float32
+	switch {
+	case flags&f_min > 0:
+		special = new(float32)
+		*special = low
+	case flags&f_max > 0:
+		special = new(float32)
+		*special = high
+	case flags&f_center > 0:
+		special = new(float32)
+		middle := (high + low) * 0.5
+		// if we're within a step of zero just return zero.
+		if middle > 0 && middle-step_width < 0 || middle < 0 && middle+step_width > 0 {
+			middle = 0
 		}
-		if flags&f_round_up > 0 {
-			panic("round up flag not done yet")
-		}
-		if flags&f_encode_zero > 0 {
-			panic("encode zero flag not done yet")
-		}
-		if flags&f_encode_ints > 0 {
-			panic("encode ints flag not done yet")
+		*special = middle
+	}
+
+	return func(br bit.Reader) interface{} {
+		if special != nil && bit.ReadBool(br) {
+			Debug.Printf("decode float type: %s low: %f high: %f bits: %d steps: %d span: %f flags: %d special: %v", f._type.String(), low, high, bits, steps, span, flags, *special)
+			return *special
 		}
-		return nil
+		u := br.ReadBits(bits)
+		out := low + float32(u)*inv_steps*span
+		Debug.Printf("decode float type: %s low: %f high: %f bits: %d bitVal: %d steps: %d span: %f flags: %d output: %v", f._type.String(), low, high, bits, u, steps, span, flags, out)
+		return out
 	}
 }
 

ent/selection.go

@@ -16,17 +16,16 @@ type selection struct {
 	vals  [6]int
 }
 
-func (s selection) path() []int { return s.vals[:s.count] }
+func (s selection) String() string { return fmt.Sprint(s.path()) }
+func (s selection) path() []int    { return s.vals[:s.count] }
 
-func (s selection) fill(offset int, dest slotted, br bit.Reader) error {
+func (s selection) fill(offset int, displayPath string, dest slotted, br bit.Reader) error {
 	slot := s.vals[offset]
-
-	Debug.Printf("fill selection %v", s)
 	switch s.count - offset {
 	case 0:
 		panic("selection makes no sense")
 	case 1:
-		fn := dest.getSlotDecoder(slot)
+		fn := dest.slotDecoder(slot)
 		if fn == nil {
 			switch v := dest.(type) {
 			case *Entity:
@@ -36,18 +35,17 @@ func (s selection) fill(offset int, dest slotted, br bit.Reader) error {
 			}
 		}
 		val := fn(br)
-		old := dest.getSlotValue(slot)
+		old := dest.slotValue(slot)
 		dest.setSlotValue(slot, val)
-		Debug.Printf("%v -> %v", old, val)
+		Debug.Printf("%s %s (%s): %v -> %v", s, fmt.Sprintf("%s.%s", displayPath, dest.slotName(slot)), dest.slotType(slot), old, val)
 		return nil
 	default:
-		Debug.Printf("fill child selection...")
-		v := dest.getSlotValue(slot)
+		v := dest.slotValue(slot)
 		vs, ok := v.(slotted)
 		if !ok {
 			return fmt.Errorf("child selection refers to a slot that doesn't contain a slotted value")
 		}
-		return s.fill(offset+1, vs, br)
+		return s.fill(offset+1, fmt.Sprintf("%s.%s", displayPath, dest.slotName(slot)), vs, br)
 	}
 }
 

ent/slotted.go

@@ -5,19 +5,21 @@ import (
 )
 
 type slotted interface {
-	getSlotValue(int) interface{}
+	slotName(int) string
+	slotValue(int) interface{}
+	slotType(int) string
+	slotDecoder(int) decoder
 	setSlotValue(int, interface{})
-	getSlotDecoder(int) decoder
 }
 
-func fillSlots(dest slotted, sr *selectionReader, br bit.Reader) error {
+func fillSlots(dest slotted, displayPath string, sr *selectionReader, br bit.Reader) error {
 	selections, err := sr.readSelections(br, htree)
 	if err != nil {
 		return err
 	}
 
 	for _, s := range selections {
-		if err := s.fill(0, dest, br); err != nil {
+		if err := s.fill(0, displayPath, dest, br); err != nil {
 			return err
 		}
 	}