Implemented polygons.

src/cmd/test/main.go

@@ -24,12 +24,13 @@ type Rect struct {
 }
 
 type Tri struct {
-	*gx.DrawableTriangles
+	*gx.DrawablePolygon
 }
 
 func NewTri() *Tri {
 	ret := &Tri{}
-	ret.DrawableTriangles = &gx.DrawableTriangles{}
+	ret.DrawablePolygon = &gx.DrawablePolygon{}
+	ret.Transform.S = gx.V(1, 1)
 	
 	ret.Triangles = gx.Triangles{
 		gx.Triangle{
@@ -88,6 +89,7 @@ var (
 	player *Player
 	rectMove gx.Rectangle
 	rect *Rect
+	tri *Tri
 )
 
 func NewPlayer() *Player {
@@ -190,6 +192,12 @@ func (p *Player) Update(e *gx.Engine) error {
 		} else {
 			c.RA.Y += gx.Pi * p.MoveSpeed * dt
 		}
+	case ebiten.KeyV :
+		if e.KeyIsPressed(ebiten.KeyShift) {
+			tri.R -= gx.Pi * 0.3 * dt
+		} else {
+			tri.R += gx.Pi * 0.3 * dt
+		}
 	case ebiten.KeyLeftBracket :
 		if e.KeyIsPressed(ebiten.KeyShift) {
 			rect.R -= gx.Pi * 0.3 * dt
@@ -241,7 +249,7 @@ func main() {
 
 	player = NewPlayer()
 	rect = NewRect()
-	tri := NewTri()
+	tri = NewTri()
 	
 	e.Add(1, &Debug{})
 	e.Add(0, player)

src/gx/polygon.go

@@ -1,29 +1,52 @@
 package gx
 
+import (
+)
+
 type PolygonTriangle struct {
-	P, S int
+	T, S int
 }
 
+// Grouped triangles type.
 type Polygon struct {
 	Transform
-	base Triangle
-	triangles []PolygonTriangle
+	Triangles
 }
 
+// Polygon that can be drawn.
 type DrawablePolygon struct {
 	Polygon
+	
 	ShaderOptions
+	Visibility
+	Colority
 }
 
-func NewPolygon(base Triangle) *Polygon {
-	ret := &Polygon{
-		Transform: T(),
-		base: base,
+func (p *Polygon) MakeTriangles() Triangles {
+	mv := p.Matrix()
+	m := &mv
+	
+	ret := make(Triangles, len(p.Triangles))
+	for i, t := range p.Triangles {
+		ret[i] = Triangle{
+			t[0].Apply(m),
+			t[1].Apply(m),
+			t[2].Apply(m),
+		}
 	}
+	
 	return ret
 }
 
-func (p *Polygon) Triangles() Triangles {
-	return Triangles{}
+func (p *DrawablePolygon) Draw(
+	e *Engine,
+	i *Image,
+) {
+	(&DrawableTriangles{
+		Visibility: p.Visibility,
+		Colority: p.Colority,
+		ShaderOptions: p.ShaderOptions,
+		Triangles: p.MakeTriangles(),
+	}).Draw(e, i)
 }