create showcase for many different models!

This will end up in the README, in higher resolution of course.

Author: unixpickle

examples/decoration/curvy_thing/main.go

@@ -32,7 +32,8 @@ func main() {
 		},
 	}
 	log.Println("Creating mesh...")
-	mesh := model3d.MarchingCubesSearch(solid, 0.01, 8)
+	mesh := model3d.MarchingCubesSearch(solid, 0.03, 8)
+	mesh = mesh.EliminateCoplanar(1e-8)
 
 	log.Println("Saving results...")
 	mesh.SaveGroupedSTL("curvy_thing.stl")

examples/decoration/curvy_thing/rendering.png

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"fmt"
 	"io/ioutil"
 	"log"
 	"math"
@@ -37,10 +38,54 @@ func main() {
 		return [3]float64{79.0 / 255, 53.0 / 255, 0}
 	}
 
+	outsideMesh := model3d.NewMesh()
+	insideMesh := model3d.NewMesh()
+	stemMesh := model3d.NewMesh()
+
 	log.Println("Creating mesh...")
 	mesh := model3d.MarchingCubesSearch(base, 0.02, 8)
 	mesh.AddMesh(model3d.MarchingCubesSearch(lid, 0.02, 8))
 
+	fmt.Println(mesh.Min(), mesh.Max())
+
+	dec := &model3d.Decimator{
+		FeatureAngle:       0.1,
+		PlaneDistance:      4e-4,
+		BoundaryDistance:   1e-5,
+		MinimumAspectRatio: 0.01,
+	}
+	fmt.Println("before", len(mesh.TriangleSlice()))
+	mesh = dec.Decimate(mesh)
+	fmt.Println("after", len(mesh.TriangleSlice()))
+
+	mesh.Iterate(func(t *model3d.Triangle) {
+		c := t[0]
+		if (PumpkinSolid{Scale: 1.025}).Contains(c) {
+			expectedNormal := t[0].Geo().Coord3D()
+			if math.Abs(expectedNormal.Dot(t.Normal())) > 0.5 {
+				outsideMesh.Add(t)
+			} else {
+				insideMesh.Add(t)
+			}
+		} else {
+			stemMesh.Add(t)
+		}
+	})
+
+	mat := model3d.NewMatrix3Rotation(
+		model3d.Coord3D{X: 1}, math.Pi/2,
+	)
+	mat = model3d.NewMatrix3Rotation(
+		model3d.Coord3D{Z: 1}, -math.Pi/2,
+	).Mul(mat)
+	outsideMesh = outsideMesh.MapCoords(mat.MulColumn)
+	insideMesh = insideMesh.MapCoords(mat.MulColumn)
+	stemMesh = stemMesh.MapCoords(mat.MulColumn)
+
+	outsideMesh.SaveGroupedSTL("pumpkin_outside.stl")
+	insideMesh.SaveGroupedSTL("pumpkin_inside.stl")
+	stemMesh.SaveGroupedSTL("pumpkin_stem.stl")
+
 	log.Println("Saving mesh...")
 	ioutil.WriteFile("pumpkin.zip", mesh.EncodeMaterialOBJ(colorFunc), 0755)
 

examples/decoration/pumpkin/main.go

@@ -13,7 +13,7 @@ import (
 const (
 	AdditionSamples = 1000
 	KeepSamples     = 990
-	GridSize        = 3
+	GridSize        = 10
 )
 
 func main() {
@@ -50,7 +50,7 @@ func main() {
 			for i := 0; i < 100; i++ {
 				rock = AddConstraint(rock)
 			}
-			min := model3d.Coord3D{X: float64(i) * 1.1, Y: float64(j) * 1.1, Z: 0}
+			min := model3d.Coord3D{X: float64(i)*5.0 + rand.Float64()*4, Y: float64(j)*5.0 + rand.Float64()*4, Z: 0}
 			mesh.AddMesh(rock.Mesh().MapCoords(min.Add))
 		}
 	}

examples/decoration/pumpkin/rendering.png

@@ -24,7 +24,14 @@ func main() {
 	}
 	collider := model3d.MeshToCollider(m)
 	solid := model3d.NewColliderSolidHollow(collider, 0.1)
-	m1 := model3d.MarchingCubesSearch(solid, 0.01, 8).Blur(-1)
+	m1 := model3d.MarchingCubesSearch(solid, 0.02, 8)
+	dec := &model3d.Decimator{
+		FeatureAngle:       0.1,
+		PlaneDistance:      4e-4,
+		BoundaryDistance:   1e-5,
+		MinimumAspectRatio: 0.01,
+	}
+	m1 = dec.Decimate(m1)
 	m1.SaveGroupedSTL("rose.stl")
 
 	log.Println("Generating rendering...")

examples/decoration/rock/main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"fmt"
 	"log"
 	"math"
 
@@ -32,11 +33,21 @@ func main() {
 		Ratio: 0.5,
 	}
 
-	mesh := model3d.MarchingCubesSearch(model3d.TransformSolid(ax, VaseSolid{}), 0.015, 8)
+	mesh := model3d.MarchingCubesSearch(model3d.TransformSolid(ax, VaseSolid{}), 0.02, 8)
 	mesh = mesh.MapCoords(ax.Inverse().Apply)
 
+	dec := &model3d.Decimator{
+		FeatureAngle:       0.1,
+		PlaneDistance:      4e-4,
+		BoundaryDistance:   1e-5,
+		MinimumAspectRatio: 0.01,
+	}
+	fmt.Println("before", len(mesh.TriangleSlice()))
+	mesh = dec.Decimate(mesh)
+	fmt.Println("after", len(mesh.TriangleSlice()))
+
 	log.Println("Flattening base...")
-	mesh = mesh.FlattenBase(0)
+	//mesh = mesh.FlattenBase(0)
 
 	log.Println("Saving STL...")
 	mesh.SaveGroupedSTL("vase.stl")

examples/decoration/rock/rendering.png

@@ -0,0 +1,16 @@
+# showcase
+
+This example renders a bunch of different 3D models created by various `model3d` examples. It is meant to produce a sort of "banner ad" for `model3d` as a whole.
+
+Included are:
+
+ * Wine glass - `examples/parody/place_setting`
+ * Pumpkin - `examples/decoration/pumpkin`
+ * Curvy thing - `examples/decoration/curvy_thing`
+ * Vase - `examples/decoration/vase`
+ * Rose - `examples/decoration/rose`
+ * Rocks - `examples/decoration/rock`
+
+The result looks like this:
+
+![Output](output.png)

examples/decoration/rose/main.go

@@ -0,0 +1,30 @@
+package main
+
+import "github.com/unixpickle/model3d"
+
+var LightDirection = model3d.Coord3D{X: 2, Y: -3, Z: 3}.Normalize()
+
+const (
+	CameraY = -5
+	CameraZ = 4
+
+	WineGlassX = -6.5
+	WineGlassY = 9.0
+
+	PumpkinX = -2
+	PumpkinY = 10
+
+	RocksY = 15.0
+
+	VaseX          = 5
+	VaseY          = 11
+	RoseX          = VaseX
+	RoseY          = VaseY
+	RoseZ          = 7
+	RoseStemRadius = 0.15
+
+	CurvyThingX = 1.8
+	CurvyThingY = 9.0
+
+	RoomRadius = 100.0
+)

examples/decoration/rose/rendering.png

@@ -0,0 +1,65 @@
+package main
+
+import (
+	"fmt"
+	"math"
+
+	"github.com/unixpickle/model3d/render3d"
+
+	"github.com/unixpickle/model3d"
+)
+
+func main() {
+	scene := render3d.JoinedObject{
+		NewFloorObject(),
+		NewDomeObject(),
+		ReadVase(),
+		ReadRose(),
+		ReadWineGlass(),
+		ReadPumpkin(),
+		ReadRocks(),
+		ReadCurvyThing(),
+	}
+
+	RenderScene(scene)
+}
+
+func RenderScene(scene render3d.Object) {
+	renderer := render3d.RecursiveRayTracer{
+		Camera: render3d.NewCameraAt(model3d.Coord3D{Y: CameraY, Z: CameraZ},
+			model3d.Coord3D{Y: RoomRadius, Z: CameraZ}, math.Pi/3.6),
+
+		FocusPoints: []render3d.FocusPoint{
+			&render3d.PhongFocusPoint{
+				Target: LightDirection.Scale(RoomRadius),
+				Alpha:  20.0,
+				MaterialFilter: func(m render3d.Material) bool {
+					switch m.(type) {
+					case *render3d.PhongMaterial:
+						return true
+					case *render3d.LambertMaterial:
+						return true
+					}
+					return false
+				},
+			},
+		},
+		FocusPointProbs: []float64{0.3},
+
+		MaxDepth:   10,
+		NumSamples: 100,
+		Antialias:  1.0,
+		Cutoff:     1e-4,
+
+		LogFunc: func(p, samples float64) {
+			fmt.Printf("\rRendering %.1f%%...", p*100)
+		},
+	}
+
+	fmt.Println("Variance:", renderer.RayVariance(scene, 200, 133, 2))
+
+	img := render3d.NewImage(480, 320)
+	renderer.Render(img, scene)
+	fmt.Println()
+	img.Save("output.png")
+}