From d9100b506ffcb0378fe33ee7dc171efc72b96fd5 Mon Sep 17 00:00:00 2001
From: Elias Naur <mail@eliasnaur.com>
Date: Mon, 14 Oct 2019 20:20:56 +0200
Subject: [PATCH] op,op/paint: remove aux awareness from Ops

Aux data is now entirely confined to the writers (Path) and the
ops Reader parser.

Signed-off-by: Elias Naur <mail@eliasnaur.com>
---
 op/op.go         | 60 +++++++++---------------------------------------
 op/paint/path.go | 30 +++++++++++++-----------
 2 files changed, 27 insertions(+), 63 deletions(-)

diff --git a/op/op.go b/op/op.go
index 6ac3da1b..2ea29918 100644
--- a/op/op.go
+++ b/op/op.go
@@ -78,10 +78,6 @@ type Ops struct {
 
 	stackDepth int
 	macroDepth int
-
-	inAux  bool
-	auxOff int
-	auxLen int
 }
 
 // StackOp can save and restore the operation state
@@ -150,7 +146,6 @@ func (s *StackOp) Pop() {
 
 // Reset the Ops, preparing it for re-use.
 func (o *Ops) Reset() {
-	o.inAux = false
 	o.stackDepth = 0
 	// Leave references to the GC.
 	for i := range o.refs {
@@ -161,62 +156,30 @@ func (o *Ops) Reset() {
 	o.version++
 }
 
-// Internal use only.
+// Data is for internal use only.
 func (o *Ops) Data() []byte {
 	return o.data
 }
 
-// Internal use only.
+// Refs is for internal use only.
 func (o *Ops) Refs() []interface{} {
 	return o.refs
 }
 
-// Internal use only.
+// PC is for internal use only.
+func (o *Ops) PC() int {
+	return o.pc().data
+}
+
+// Version is for internal use only.
 func (o *Ops) Version() int {
 	return o.version
 }
 
-// Internal use only.
-func (o *Ops) Aux() []byte {
-	if !o.inAux {
-		return nil
-	}
-	aux := o.data[o.auxOff+opconst.TypeAuxLen:]
-	return aux[:o.auxLen]
-}
-
-func (d *Ops) write(op []byte, refs ...interface{}) {
-	d.data = append(d.data, op...)
-	d.refs = append(d.refs, refs...)
-}
-
-// Internal use only.
+// Write is for internal use only.
 func (o *Ops) Write(op []byte, refs ...interface{}) {
-	t := opconst.OpType(op[0])
-	if len(refs) != t.NumRefs() {
-		panic("invalid ref count")
-	}
-	switch t {
-	case opconst.TypeAux:
-		// Write only the data.
-		op = op[1:]
-		if !o.inAux {
-			o.inAux = true
-			o.auxOff = o.pc().data
-			o.auxLen = 0
-			header := make([]byte, opconst.TypeAuxLen)
-			header[0] = byte(opconst.TypeAux)
-			o.write(header)
-		}
-		o.auxLen += len(op)
-	default:
-		o.endAux()
-	}
-	o.write(op, refs...)
-}
-
-func (o *Ops) endAux() {
-	o.inAux = false
+	o.data = append(o.data, op...)
+	o.refs = append(o.refs, refs...)
 }
 
 func (o *Ops) pc() pc {
@@ -242,7 +205,6 @@ func (m *MacroOp) Stop() {
 	if !m.recording {
 		panic("not recording")
 	}
-	m.ops.endAux()
 	m.ops.macroDepth--
 	m.recording = false
 	m.fill()
diff --git a/op/paint/path.go b/op/paint/path.go
index b259aea3..5f70c46f 100644
--- a/op/paint/path.go
+++ b/op/paint/path.go
@@ -19,6 +19,7 @@ import (
 // supplied to Begin.
 type Path struct {
 	ops       *op.Ops
+	pc        int
 	firstVert int
 	nverts    int
 	maxy      float32
@@ -50,6 +51,8 @@ func (p ClipOp) Add(o *op.Ops) {
 func (p *Path) Begin(ops *op.Ops) {
 	p.ops = ops
 	p.macro.Record(ops)
+	ops.Write([]byte{byte(opconst.TypeAux)})
+	p.pc = ops.PC()
 }
 
 // MoveTo moves the pen to the given position.
@@ -62,7 +65,7 @@ func (p *Path) Move(to f32.Point) {
 
 // end completes the current contour.
 func (p *Path) end() {
-	aux := p.ops.Aux()
+	aux := p.ops.Data()[p.pc:]
 	bo := binary.LittleEndian
 	// Fill in maximal Y coordinates of the NW and NE corners.
 	for i := p.firstVert; i < p.nverts; i++ {
@@ -246,20 +249,19 @@ func (p *Path) vertex(cornerx, cornery int16, ctrl, to f32.Point) {
 		ToX:     to.X,
 		ToY:     to.Y,
 	}
-	data := make([]byte, path.VertStride+1)
-	data[0] = byte(opconst.TypeAux)
+	data := make([]byte, path.VertStride)
 	bo := binary.LittleEndian
-	data[1] = byte(uint16(v.CornerX))
-	data[2] = byte(uint16(v.CornerX) >> 8)
-	data[3] = byte(uint16(v.CornerY))
-	data[4] = byte(uint16(v.CornerY) >> 8)
-	bo.PutUint32(data[5:], math.Float32bits(v.MaxY))
-	bo.PutUint32(data[9:], math.Float32bits(v.FromX))
-	bo.PutUint32(data[13:], math.Float32bits(v.FromY))
-	bo.PutUint32(data[17:], math.Float32bits(v.CtrlX))
-	bo.PutUint32(data[21:], math.Float32bits(v.CtrlY))
-	bo.PutUint32(data[25:], math.Float32bits(v.ToX))
-	bo.PutUint32(data[29:], math.Float32bits(v.ToY))
+	data[0] = byte(uint16(v.CornerX))
+	data[1] = byte(uint16(v.CornerX) >> 8)
+	data[2] = byte(uint16(v.CornerY))
+	data[3] = byte(uint16(v.CornerY) >> 8)
+	bo.PutUint32(data[6:], math.Float32bits(v.MaxY))
+	bo.PutUint32(data[8:], math.Float32bits(v.FromX))
+	bo.PutUint32(data[12:], math.Float32bits(v.FromY))
+	bo.PutUint32(data[16:], math.Float32bits(v.CtrlX))
+	bo.PutUint32(data[20:], math.Float32bits(v.CtrlY))
+	bo.PutUint32(data[24:], math.Float32bits(v.ToX))
+	bo.PutUint32(data[28:], math.Float32bits(v.ToY))
 	p.ops.Write(data)
 }