diff --git a/box.go b/box.go
index ca5c472..a127c85 100644
--- a/box.go
+++ b/box.go
@@ -76,11 +76,10 @@ func (b *Box) GetItems() []*Item {
 
 // PutItem Attempts to place an element at anchor point p of box b.
 func (b *Box) PutItem(item *Item, p Pivot) bool {
-	if !b.canTryToPlace(item) {
+	if !b.canQuota(item) {
 		return false
 	}
 
-	fit := false
 	item.position = p
 
 	for rt := RotationTypeWhd; rt <= RotationTypeWdh; rt++ {
@@ -91,34 +90,22 @@ func (b *Box) PutItem(item *Item, p Pivot) bool {
 			continue
 		}
 
-		fit = true
-
 		for _, ib := range b.items {
 			if ib.Intersect(item) {
 				return false
 			}
 		}
 
-		if fit {
-			b.insert(item)
+		b.insert(item)
 
-			break
-		}
+		return true
 	}
 
-	return fit
+	return false
 }
 
-func (b *Box) canTryToPlace(item *Item) bool {
-	if b.itemsVolume+item.volume > b.volume {
-		return false
-	}
-
-	if b.itemsWeight+item.weight > b.maxWeight {
-		return false
-	}
-
-	return true
+func (b *Box) canQuota(item *Item) bool {
+	return b.itemsVolume+item.volume <= b.volume && b.itemsWeight+item.weight <= b.maxWeight
 }
 
 func (b *Box) insert(item *Item) {
@@ -128,7 +115,7 @@ func (b *Box) insert(item *Item) {
 }
 
 func (b *Box) purge() {
-	b.items = b.items[:0] // keep allocated memory
+	b.items = make([]*Item, 0, len(b.items))
 	b.itemsVolume = 0
 	b.itemsWeight = 0
 }
diff --git a/go.mod b/go.mod
index 937aae4..429ddca 100644
--- a/go.mod
+++ b/go.mod
@@ -3,6 +3,7 @@ module github.com/bavix/boxpacker3
 go 1.20
 
 require (
+	github.com/g3n/engine v0.2.0
 	github.com/google/uuid v1.3.0
 	github.com/stretchr/testify v1.8.4
 	golang.org/x/exp v0.0.0-20230801115018-d63ba01acd4b
@@ -10,6 +11,10 @@ require (
 
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/go-gl/glfw/v3.3/glfw v0.0.0-20210410170116-ea3d685f79fb // indirect
+	github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
+	golang.org/x/image v0.0.0-20210607152325-775e3b0c77b9 // indirect
+	gopkg.in/yaml.v2 v2.4.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )
diff --git a/go.sum b/go.sum
index 2ffca3b..b1a79d1 100644
--- a/go.sum
+++ b/go.sum
@@ -1,5 +1,11 @@
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/g3n/engine v0.2.0 h1:7dmj4c+3xHcBnYrVmRuVf/oZ2JycxJU9Y+2FQj1Af2Y=
+github.com/g3n/engine v0.2.0/go.mod h1:rnj8jiLdKEDI8VbveKhmdL4rovjjy+uxNP5YROg2x8g=
+github.com/go-gl/glfw/v3.3/glfw v0.0.0-20210410170116-ea3d685f79fb h1:T6gaWBvRzJjuOrdCtg8fXXjKai2xSDqWTcKFUPuw8Tw=
+github.com/go-gl/glfw/v3.3/glfw v0.0.0-20210410170116-ea3d685f79fb/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
+github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0 h1:DACJavvAHhabrF08vX0COfcOBJRhZ8lUbR+ZWIs0Y5g=
+github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0/go.mod h1:E/TSTwGwJL78qG/PmXZO1EjYhfJinVAhrmmHX6Z8B9k=
 github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
 github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
@@ -8,7 +14,13 @@ github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcU
 github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
 golang.org/x/exp v0.0.0-20230801115018-d63ba01acd4b h1:r+vk0EmXNmekl0S0BascoeeoHk/L7wmaW2QF90K+kYI=
 golang.org/x/exp v0.0.0-20230801115018-d63ba01acd4b/go.mod h1:FXUEEKJgO7OQYeo8N01OfiKP8RXMtf6e8aTskBGqWdc=
+golang.org/x/image v0.0.0-20210607152325-775e3b0c77b9 h1:D0iM1dTCbD5Dg1CbuvLC/v/agLc79efSj/L35Q3Vqhs=
+golang.org/x/image v0.0.0-20210607152325-775e3b0c77b9/go.mod h1:023OzeP/+EPmXeapQh35lcL3II3LrY8Ic+EFFKVhULM=
+golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
+gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
diff --git a/internal/visualize3d/main.go b/internal/visualize3d/main.go
new file mode 100644
index 0000000..3f8233a
--- /dev/null
+++ b/internal/visualize3d/main.go
@@ -0,0 +1,127 @@
+//nolint:all
+package main
+
+import (
+	"math/rand"
+	"time"
+
+	"github.com/g3n/engine/app"
+	"github.com/g3n/engine/camera"
+	"github.com/g3n/engine/core"
+	"github.com/g3n/engine/geometry"
+	"github.com/g3n/engine/gls"
+	"github.com/g3n/engine/graphic"
+	"github.com/g3n/engine/light"
+	"github.com/g3n/engine/material"
+	"github.com/g3n/engine/math32"
+	"github.com/g3n/engine/renderer"
+	"github.com/google/uuid"
+
+	"github.com/bavix/boxpacker3"
+)
+
+const (
+	BoxTypeF       = "8ec81501-11a4-4b3f-9a52-7cd2f9c8370c"
+	BoxTypeE       = "9c69baf8-1ca3-46a0-9fc2-6f15ad9fef9a"
+	BoxTypeG       = "2c5279d3-48ad-451b-b673-f6d9be7fc6f6"
+	BoxTypeC       = "7f1cc68f-d554-4094-8734-c68df5c13154"
+	BoxTypeB       = "76cede41-86bb-4487-bfb0-9513f032d53e"
+	BoxTypeA       = "8e10cebf-cee6-4136-b060-1587b993d083"
+	BoxTypeStd     = "ba973206-aa64-493b-b37a-c53192cde8fd"
+	BoxTypeNotStd1 = "cb1ed5b8-7405-48c5-bfd0-d86f75c99261"
+	BoxTypeNotStd2 = "d91e2661-aebb-4a55-bfb5-4ff9c6e3c008"
+	BoxTypeNotStd3 = "a0ecd730-375a-4313-bbe8-820710606b3d"
+	BoxTypeNotStd4 = "6dff37f0-4dd1-4143-abdc-c19ab94f2e68"
+	BoxTypeNotStd5 = "abac6d59-b51f-4d62-a338-42aca7afe1cc"
+	BoxTypeNotStd6 = "981ffb30-a7b9-4d9e-820e-04de2145763e"
+)
+
+func NewDefaultBoxList() []*boxpacker3.Box {
+	return []*boxpacker3.Box{
+		boxpacker3.NewBox(BoxTypeF, 220, 185, 50, 20000),           // 0
+		boxpacker3.NewBox(BoxTypeE, 165, 215, 100, 20000),          // 1
+		boxpacker3.NewBox(BoxTypeG, 265, 165, 190, 20000),          // 2
+		boxpacker3.NewBox(BoxTypeC, 425, 165, 190, 20000),          // 3
+		boxpacker3.NewBox(BoxTypeB, 425, 265, 190, 20000),          // 4
+		boxpacker3.NewBox(BoxTypeA, 425, 265, 380, 20000),          // 5
+		boxpacker3.NewBox(BoxTypeStd, 530, 380, 265, 20000),        // 6
+		boxpacker3.NewBox(BoxTypeNotStd1, 1000, 500, 500, 20000),   // 7
+		boxpacker3.NewBox(BoxTypeNotStd2, 1000, 1000, 1000, 20000), // 8
+		boxpacker3.NewBox(BoxTypeNotStd3, 2000, 500, 500, 20000),   // 9
+		boxpacker3.NewBox(BoxTypeNotStd4, 2000, 2000, 2000, 20000), // 10
+		boxpacker3.NewBox(BoxTypeNotStd5, 2500, 2500, 2500, 20000), // 11
+		boxpacker3.NewBox(BoxTypeNotStd6, 3000, 3000, 3000, 20000), // 12
+	}
+}
+
+func main() {
+	a := app.App()
+	scene := core.NewNode()
+
+	cam := camera.NewPerspective(1, 1, 3000, 60, camera.Vertical)
+	cam.SetPosition(0, 0, 3)
+	scene.Add(cam)
+	camera.NewOrbitControl(cam)
+
+	packer := boxpacker3.NewPacker()
+
+	boxes := NewDefaultBoxList()
+	items := []*boxpacker3.Item{
+		// 5
+		boxpacker3.NewItem(uuid.New().String(), 100, 100, 5, 2690),
+		boxpacker3.NewItem(uuid.New().String(), 100, 5, 100, 2690),
+		boxpacker3.NewItem(uuid.New().String(), 5, 100, 100, 2690),
+		boxpacker3.NewItem(uuid.New().String(), 5, 100, 100, 2690),
+		boxpacker3.NewItem(uuid.New().String(), 5, 100, 100, 2690),
+		boxpacker3.NewItem(uuid.New().String(), 5, 100, 100, 2690),
+
+		// 35
+		boxpacker3.NewItem(uuid.New().String(), 35, 100, 100, 2690),
+		boxpacker3.NewItem(uuid.New().String(), 35, 100, 100, 2690),
+	}
+
+	packResult, _ := packer.Pack(boxes, items)
+
+	for _, box := range packResult.Boxes {
+		if len(box.GetItems()) == 0 {
+			continue
+		}
+
+		boxGeo := geometry.NewBox(float32(box.GetWidth()), float32(box.GetHeight()), float32(box.GetDepth()))
+		mat := material.NewStandard(math32.NewColor("DarkGreen"))
+		mat.SetOpacity(0.25)
+		boxMesh := graphic.NewMesh(boxGeo, mat)
+		boxMesh.SetPosition(0, 0, 0)
+		scene.Add(boxMesh)
+
+		for _, item := range box.GetItems() {
+			dimension := item.GetDimension()
+
+			itemGeo := geometry.NewBox(float32(dimension[0]), float32(dimension[1]), float32(dimension[2]))
+			mat := material.NewStandard(math32.NewColorHex(uint(rand.Uint32())))
+			itemMesh := graphic.NewMesh(itemGeo, mat)
+			mat.SetOpacity(0.7)
+
+			itemMesh.SetPosition(
+				float32(item.GetPosition()[boxpacker3.WidthAxis])-float32(box.GetWidth())/2+float32(dimension[0])/2,
+				float32(item.GetPosition()[boxpacker3.HeightAxis])-float32(box.GetHeight())/2+float32(dimension[1])/2,
+				float32(item.GetPosition()[boxpacker3.DepthAxis])-float32(box.GetDepth())/2+float32(dimension[2])/2)
+
+			scene.Add(itemMesh)
+		}
+
+		break
+	}
+
+	scene.Add(light.NewAmbient(&math32.Color{1.0, 1.0, 1.0}, 0.8))
+	pointLight := light.NewPoint(&math32.Color{1, 1, 0}, 5.0)
+	pointLight.SetPosition(1, 0, 2)
+	scene.Add(pointLight)
+
+	a.Gls().ClearColor(0.5, 0.5, 0.5, 1.0)
+
+	a.Run(func(renderer *renderer.Renderer, deltaTime time.Duration) {
+		a.Gls().Clear(gls.DEPTH_BUFFER_BIT | gls.STENCIL_BUFFER_BIT | gls.COLOR_BUFFER_BIT)
+		renderer.Render(scene, cam)
+	})
+}
diff --git a/item.go b/item.go
index 49ecf53..d7961d4 100644
--- a/item.go
+++ b/item.go
@@ -26,7 +26,7 @@ func (it itemSlice) Len() int {
 }
 
 func (it itemSlice) Less(i, j int) bool {
-	return it[i].GetVolume() < it[j].GetVolume()
+	return it[i].volume < it[j].volume
 }
 
 func (it itemSlice) Swap(i, j int) {
diff --git a/packer.go b/packer.go
index 6d10d75..943e7b0 100644
--- a/packer.go
+++ b/packer.go
@@ -59,7 +59,7 @@ func (p *Packer) preferredSort(boxes boxSlice, items itemSlice) boxSlice {
 
 	for i, b := range boxes {
 		if b.volume >= volume && b.maxWeight >= weight && b.maxLength >= maxLength {
-			return append(boxSlice{b}, slices.Delete(boxes, i, i)...)
+			return append(boxSlice{b}, slices.Delete(boxes, i, i+1)...)
 		}
 	}
 
@@ -94,18 +94,14 @@ func (p *Packer) packToBox(b *Box, items []*Item) []*Item {
 
 				switch pt {
 				case WidthAxis:
-					pv[WidthAxis] += +dimension[WidthAxis]
+					pv[WidthAxis] += dimension[WidthAxis]
 				case HeightAxis:
 					pv[HeightAxis] += dimension[HeightAxis]
 				case DepthAxis:
 					pv[DepthAxis] += dimension[DepthAxis]
 				}
 
-				if b.PutItem(i, pv) {
-					fitted = true
-
-					break
-				}
+				fitted = b.PutItem(i, pv)
 			}
 		}
 
@@ -131,7 +127,7 @@ func (p *Packer) packToBox(b *Box, items []*Item) []*Item {
 
 							switch pt {
 							case WidthAxis:
-								pv[WidthAxis] += +dimension[WidthAxis]
+								pv[WidthAxis] += dimension[WidthAxis]
 							case HeightAxis:
 								pv[HeightAxis] += dimension[HeightAxis]
 							case DepthAxis: