Changed the way circles are handled

bvg_test.go

@@ -2,6 +2,7 @@ package bvg
 
 import (
 	"bytes"
+	"math"
 	"io"
 	"fmt"
 	"os"
@@ -25,7 +26,7 @@ func TestBvg(t *testing.T) {
 	}
 	t.Log("Added Triangles" + fmt.Sprintf(" bytes Encoded: %d", bytesEncoded))
 	for i := -1.0; i < 0.998; i += 0.1 {
-		in.Circles = append(in.Circles, NewCircleGrad(center, NewPtCol(i, 0.6, 232, 54, 87, 255)))
+		in.Circles = append(in.Circles, NewCircle(center.RelPt(i, math.Pi*i), 0.5, 0.999))
 		bytesEncoded += 41
 	}
 	t.Log("Added Circles" + fmt.Sprintf(" bytes Encoded: %d", bytesEncoded))

dec.go

@@ -31,9 +31,11 @@ func Decode(b []byte) (bvg *Bvg , err error) {
 			))
 			i += n + 1
 		case byte('c'):
-			Pts, n := PointsFromBytes(b[i+1:i+42], 2)
-			bvg.Circles = append(bvg.Circles, NewCircleGrad(Pts[0], Pts[1]))
-			i += n + 1
+			Pts, n := PointsFromBytes(b[i+1:i+21], 1)
+			t1 := Float64FromBytes(b[i+21:i+29])
+			t2 := Float64FromBytes(b[i+29:i+37])
+			bvg.Circles = append(bvg.Circles, NewCircle(Pts[0], t1, t2))
+			i += n + 1 + 16
 		case byte('p'):
 			n := binary.LittleEndian.Uint32(b[i+1 : i+5])
 		//	fmt.Println(n)

enc.go

@@ -2,7 +2,7 @@ package bvg
 
 import (
 	"encoding/binary"
-//	"fmt"
+	//	"fmt"
 	//	"fmt"
 	"io"
 	"math"
@@ -37,7 +37,6 @@ func NewPt(x, y float64) *Point {
 	}
 }
 
-
 func (p *Point) Dist(p1 *Point) float64 {
 	return math.Sqrt((p.X-p1.X)*(p.X-p1.X) + (p.Y-p1.Y)*(p.Y-p1.Y))
 }
@@ -87,21 +86,19 @@ func NewLine(p1, p2 *Point) *Line {
 }
 
 type Circle struct {
-	P1 *Point
-	P2 *Point
+	P *Point
+	// r is the complete radius of the circle 
+	// the alpha at r is 0
+	// t is threshold upto which the color of the circle 
+	// does not fade
+	r, t float64
 }
 
-func NewCircle(p1 *Point, r float64) *Circle {
+func NewCircle(p *Point, r, t float64) *Circle {
 	return &Circle{
-		P1: p1,
-		P2: p1.RelPt(r, 0),
-	}
-}
-
-func NewCircleGrad(p1, p2 *Point) *Circle {
-	return &Circle{
-		P1: p1,
-		P2: p2,
+		P:  p,
+		r: r,
+		t: t,
 	}
 }
 
@@ -182,7 +179,7 @@ func (b *Bvg) DrawLine(l Line) {
 
 // draw a triangle from p1, p2, p3
 func (b *Bvg) DrawTriangle(t Triangle) {
-	binary.Write(b.Writer, binary.LittleEndian, int8('t'))	
+	binary.Write(b.Writer, binary.LittleEndian, int8('t'))
 	t.P1.Write(b.Writer)
 	t.P2.Write(b.Writer)
 	t.P3.Write(b.Writer)
@@ -193,17 +190,17 @@ func (b *Bvg) DrawTriangle(t Triangle) {
 // the center to colours of p2 at the circumference
 func (b *Bvg) DrawCircle(c Circle) {
 	binary.Write(b.Writer, binary.LittleEndian, int8('c'))
-	c.P1.Write(b.Writer)
-	c.P2.Write(b.Writer)
+	c.P.Write(b.Writer)
+	binary.Write(b.Writer, binary.LittleEndian, c.r)
+	binary.Write(b.Writer, binary.LittleEndian, c.t)
 }
 
-
 // draws a polygon from the points given, it triangulates by
 // using a triangle strip from the given points
 func (b *Bvg) DrawPoly(p Poly) {
 	binary.Write(b.Writer, binary.LittleEndian, int8('p'))
 	binary.Write(b.Writer, binary.LittleEndian, uint32(len(p.Pts)))
-//	fmt.Println(len(p.Pts))
+	//	fmt.Println(len(p.Pts))
 	for _, p := range p.Pts {
 		p.Write(b.Writer)
 	}
@@ -226,6 +223,6 @@ func (b *Bvg) DrawLineStrip(l LineStrip) {
 	binary.Write(b.Writer, binary.LittleEndian, uint32(len(l.Pts)))
 	for _, p := range l.Pts {
 		p.Write(b.Writer)
-		
+
 	}
 }