Point3->Int3; new Float3 type

engine/actor.go

@@ -17,13 +17,13 @@ func init() {
 // Actor handles basic movement.
 type Actor struct {
 	CollisionDomain  string // id of component to look for colliders inside of
-	Pos, Size        Point3
+	Pos, Size        Int3
 	xRem, yRem, zRem float64
 
 	game *Game
 }
 
-func (a *Actor) CollidesAt(p Point3) bool {
+func (a *Actor) CollidesAt(p Int3) bool {
 	bounds := Box{Min: p, Max: p.Add(a.Size)}
 	for c := range a.game.Query(a.CollisionDomain, ColliderType) {
 		if c.(Collider).CollidesWith(bounds) {

engine/box.go

@@ -4,7 +4,7 @@ import "image"
 
 // Box describes an axis-aligned rectangular prism.
 type Box struct {
-	Min, Max Point3
+	Min, Max Int3
 }
 
 // String returns a string representation of b like "(3,4,5)-(6,5,8)".
@@ -32,7 +32,7 @@ func (b Box) Overlaps(c Box) bool {
 }
 
 // Size returns b's width, height, and depth.
-func (b Box) Size() Point3 {
+func (b Box) Size() Int3 {
 	return b.Max.Sub(b.Min)
 }
 

engine/camera.go

@@ -35,7 +35,7 @@ type Camera struct {
 
 // PointAt points the camera at a particular centre point and zoom, but adjusts
 // for the bounds of the child component (if available).
-func (c *Camera) PointAt(centre Point3, zoom float64) {
+func (c *Camera) PointAt(centre Int3, zoom float64) {
 	// Special sauce: if Child has a BoundingRect, make some adjustments
 	bnd, ok := c.Child.(Bounder)
 	if !ok {

engine/game.go

@@ -41,6 +41,7 @@ type Game struct {
 	Hidden
 	ScreenSize image.Point
 	Root       interface{} // typically a *Scene or SceneRef though
+	VoxelScale Float3
 
 	dbmu     sync.RWMutex
 	byID     map[string]Identifier              // Named components by ID

engine/matrix.go

@@ -6,8 +6,8 @@ import "image"
 type IntMatrix3 [3][3]int
 
 // Apply applies the matrix to a vector to obtain a transformed vector.
-func (a IntMatrix3) Apply(v Point3) Point3 {
-	return Point3{
+func (a IntMatrix3) Apply(v Int3) Int3 {
+	return Int3{
 		X: v.X*a[0][0] + v.Y*a[0][1] + v.Z*a[0][2],
 		Y: v.X*a[1][0] + v.Y*a[1][1] + v.Z*a[1][2],
 		Z: v.X*a[2][0] + v.Y*a[2][1] + v.Z*a[2][2],
@@ -40,19 +40,19 @@ func (a IntMatrix3) Concat(b IntMatrix3) IntMatrix3 {
 type IntMatrix3x4 [3][4]int
 
 // Apply applies the matrix to a vector to obtain a transformed vector.
-func (a IntMatrix3x4) Apply(v Point3) Point3 {
-	return Point3{
+func (a IntMatrix3x4) Apply(v Int3) Int3 {
+	return Int3{
 		X: v.X*a[0][0] + v.Y*a[0][1] + v.Z*a[0][2] + a[0][3],
 		Y: v.X*a[1][0] + v.Y*a[1][1] + v.Z*a[1][2] + a[1][3],
 		Z: v.X*a[2][0] + v.Y*a[2][1] + v.Z*a[2][2] + a[2][3],
 	}
 }
 
-// IntMatrix2x3 implements a 2 row, 3 column matrix (as two Point3 row vectors).
-type IntMatrix2x3 [2]Point3
+// IntMatrix2x3 implements a 2 row, 3 column matrix (as two row vectors).
+type IntMatrix2x3 [2]Int3
 
 // Apply applies the matrix to a vector to obtain a transformed vector.
-func (a IntMatrix2x3) Apply(v Point3) image.Point {
+func (a IntMatrix2x3) Apply(v Int3) image.Point {
 	return image.Point{
 		X: v.Dot(a[0]),
 		Y: v.Dot(a[1]),

engine/point.go

@@ -1,77 +1,78 @@
 package engine
 
 import (
+	"fmt"
 	"image"
 	"strconv"
 )
 
-// Point3 is a an element of int^3.
-type Point3 struct {
+// Int3 is a an element of int^3.
+type Int3 struct {
 	X, Y, Z int
 }
 
-// Pt3(x, y, z) is shorthand for Point3{x, y, z}.
-func Pt3(x, y, z int) Point3 {
-	return Point3{x, y, z}
+// Pt3(x, y, z) is shorthand for Int3{x, y, z}.
+func Pt3(x, y, z int) Int3 {
+	return Int3{x, y, z}
 }
 
 // String returns a string representation of p like "(3,4,5)".
-func (p Point3) String() string {
+func (p Int3) String() string {
 	return "(" + strconv.Itoa(p.X) + "," + strconv.Itoa(p.Y) + "," + strconv.Itoa(p.Z) + ")"
 }
 
 // XY applies the Z-forgetting projection. (It returns just X and Y.)
-func (p Point3) XY() image.Point {
+func (p Int3) XY() image.Point {
 	return image.Point{p.X, p.Y}
 }
 
 // Add performs vector addition.
-func (p Point3) Add(q Point3) Point3 {
-	return Point3{p.X + q.X, p.Y + q.Y, p.Z + q.Z}
+func (p Int3) Add(q Int3) Int3 {
+	return Int3{p.X + q.X, p.Y + q.Y, p.Z + q.Z}
 }
 
 // Sub performs vector subtraction.
-func (p Point3) Sub(q Point3) Point3 {
+func (p Int3) Sub(q Int3) Int3 {
 	return p.Add(q.Neg())
 }
 
 // CMul performs componentwise multiplication.
-func (p Point3) CMul(q Point3) Point3 {
-	return Point3{p.X * q.X, p.Y * q.Y, p.Z * q.Z}
+func (p Int3) CMul(q Int3) Int3 {
+	return Int3{p.X * q.X, p.Y * q.Y, p.Z * q.Z}
 }
 
 // Mul performs scalar multiplication.
-func (p Point3) Mul(k int) Point3 {
-	return Point3{p.X * k, p.Y * k, p.Z * k}
+func (p Int3) Mul(k int) Int3 {
+	return Int3{p.X * k, p.Y * k, p.Z * k}
 }
 
 // CDiv performs componentwise division.
-func (p Point3) CDiv(q Point3) Point3 {
-	return Point3{p.X / q.X, p.Y / q.Y, p.Z / q.Z}
+func (p Int3) CDiv(q Int3) Int3 {
+	return Int3{p.X / q.X, p.Y / q.Y, p.Z / q.Z}
 }
 
 // Div performs scalar division by k.
-func (p Point3) Div(k int) Point3 {
-	return Point3{p.X / k, p.Y / k, p.Z / k}
+func (p Int3) Div(k int) Int3 {
+	return Int3{p.X / k, p.Y / k, p.Z / k}
 }
 
 // Neg returns the vector pointing in the opposite direction.
-func (p Point3) Neg() Point3 {
-	return Point3{-p.X, -p.Y, -p.Z}
+func (p Int3) Neg() Int3 {
+	return Int3{-p.X, -p.Y, -p.Z}
 }
 
 // Coord returns the components of the vector.
-func (p Point3) Coord() (x, y, z int) {
+func (p Int3) Coord() (x, y, z int) {
 	return p.X, p.Y, p.Z
 }
 
 // Sign returns a sign vector.
-func (p Point3) Sign() Point3 {
-	return Point3{sign(p.X), sign(p.Y), sign(p.Z)}
+func (p Int3) Sign() Int3 {
+	return Int3{sign(p.X), sign(p.Y), sign(p.Z)}
 }
 
 // Dot returns the dot product of the two vectors.
-func (p Point3) Dot(q Point3) int {
+func (p Int3) Dot(q Int3) int {
 	return p.X*q.X + p.Y*q.Y + p.Z*q.Z
 }
 
@@ -84,3 +85,73 @@ func sign(m int) int {
 	}
 	return 1
 }
+
+func signf(m float64) float64 {
+	if m == 0 {
+		return 0
+	}
+	if m < 0 {
+		return -1
+	}
+	return 1
+}
+
+// Float3 is an element of float64^3.
+type Float3 struct {
+	X, Y, Z float64
+}
+
+// String returns a string representation of p like "(3.0,4.0,5.0)".
+func (p Float3) String() string {
+	return fmt.Sprintf("(%f,%f,%f)", p.X, p.Y, p.Z)
+}
+
+// Add performs vector addition.
+func (p Float3) Add(q Float3) Float3 {
+	return Float3{p.X + q.X, p.Y + q.Y, p.Z + q.Z}
+}
+
+// Sub performs vector subtraction.
+func (p Float3) Sub(q Float3) Float3 {
+	return p.Add(q.Neg())
+}
+
+// CMul performs componentwise multiplication.
+func (p Float3) CMul(q Float3) Float3 {
+	return Float3{p.X * q.X, p.Y * q.Y, p.Z * q.Z}
+}
+
+// Mul performs scalar multiplication.
+func (p Float3) Mul(k float64) Float3 {
+	return Float3{p.X * k, p.Y * k, p.Z * k}
+}
+
+// CDiv performs componentwise division.
+func (p Float3) CDiv(q Float3) Float3 {
+	return Float3{p.X / q.X, p.Y / q.Y, p.Z / q.Z}
+}
+
+// Div performs scalar division by k.
+func (p Float3) Div(k float64) Float3 {
+	return Float3{p.X / k, p.Y / k, p.Z / k}
+}
+
+// Neg returns the vector pointing in the opposite direction.
+func (p Float3) Neg() Float3 {
+	return Float3{-p.X, -p.Y, -p.Z}
+}
+
+// Coord returns the components of the vector.
+func (p Float3) Coord() (x, y, z float64) {
+	return p.X, p.Y, p.Z
+}
+
+// Sign returns a sign vector.
+func (p Float3) Sign() Float3 {
+	return Float3{signf(p.X), signf(p.Y), signf(p.Z)}
+}
+
+// Dot returns the dot product of the two vectors.
+func (p Float3) Dot(q Float3) float64 {
+	return p.X*q.X + p.Y*q.Y + p.Z*q.Z
+}

engine/prisms.go

@@ -33,12 +33,12 @@ type PrismMap struct {
 	Disabled
 	Hidden
 
-	Map           map[Point3]*Prism // pos -> prism
-	DrawOrderBias image.Point       // dot with pos.XY() = bias value
-	DrawOffset    image.Point       // offset applies to whole map
-	PosToDraw     IntMatrix2x3      // p.pos -> drawspace (before offset and camera and ...)
-	PosToWorld    IntMatrix3x4      // p.pos -> worldspace
-	PrismSize     Point3            // in worldspace
+	Map           map[Int3]*Prism // pos -> prism
+	DrawOrderBias image.Point     // dot with pos.XY() = bias value
+	DrawOffset    image.Point     // offset applies to whole map
+	PosToDraw     IntMatrix2x3    // p.pos -> drawspace (before offset and camera and ...)
+	PosToWorld    IntMatrix3x4    // p.pos -> worldspace
+	PrismSize     Int3            // in worldspace
 	Sheet         Sheet
 }
 
@@ -65,7 +65,7 @@ func (m *PrismMap) Transform(pt Transform) (tf Transform) {
 type Prism struct {
 	Cell int
 
-	pos Point3
+	pos Int3
 	pm  *PrismMap
 }
 

engine/projection.go

@@ -8,7 +8,7 @@ type IntProjection image.Point
 //
 // If π.X = 0, the x returned is p.X; similarly for π.Y and y.
 // Otherwise, x projects to x + z/π.X and y projects to y + z/π.Y.
-func (π IntProjection) Project(p Point3) image.Point {
+func (π IntProjection) Project(p Int3) image.Point {
 	/*
 		I'm using the π character because I'm a maths wanker.