still working

examples/marblemachine/main.go

@@ -25,6 +25,14 @@ type object struct {
 	physicsShape *cp.Shape
 }
 
+/*
+A Body appears to be what has mass, momentum
+A Shape is what touches other things, and is attached to a body.
+A shape seems to usually be made out of segments.
+
+A segment seems to be a wide line with rounded ends.
+*/
+
 func simStartFunc(sim models.Scratch) {
 	oList := []*object{}
 
@@ -33,12 +41,12 @@ func simStartFunc(sim models.Scratch) {
 
 	container := space.AddBody(cp.NewKinematicBody())
 	container.SetAngularVelocity(0.4)
-	container.SetPosition(cp.Vector{0, 0})
+	container.SetPosition(cp.Vector{X: 0, Y: 0})
 
-	a := cp.Vector{-200, -200}
-	b := cp.Vector{-200, 200}
-	c := cp.Vector{200, 200}
-	d := cp.Vector{200, -200}
+	a := cp.Vector{X: -200, Y: -200}
+	b := cp.Vector{X: -200, Y: 200}
+	c := cp.Vector{X: 200, Y: 200}
+	d := cp.Vector{X: 200, Y: -200}
 
 	AddWall(space, container, a, b, 1)
 	AddWall(space, container, b, c, 1)
@@ -55,7 +63,8 @@ func simStartFunc(sim models.Scratch) {
 
 			typ := rand.Intn(3)
 			if typ == 0 {
-				// AddBox(space, pos, mass, width, height)
+				a := AddBox(sim, space, pos, mass, width, height)
+				oList = append(oList, a)
 			} else if typ == 1 {
 				// AddSegment(space, pos, mass, width, height)
 			} else {
@@ -103,32 +112,6 @@ func createRectangleImage(width, height float64, c color.Color) image.Image {
 	return dc.Image()
 }
 
-// func createContainer(sim models.Scratch, space *cp.Space) []*object {
-// 	container := space.AddBody(cp.NewKinematicBody())
-// 	container.SetAngularVelocity(0.4)
-// 	container.SetPosition(cp.Vector{X: 0, Y: 0})
-
-// 	container
-// 	shape := space.AddShape(circle.Shape)
-
-// 	a := cp.Vector{X: -200, Y: -200}
-// 	b := cp.Vector{X: -200, Y: 200}
-// 	c := cp.Vector{X: 200, Y: 200}
-// 	d := cp.Vector{X: 200, Y: -200}
-
-// 	AddWall(space, container, a, b, 1)
-// 	AddWall(space, container, b, c, 1)
-// 	AddWall(space, container, c, d, 1)
-// 	AddWall(space, container, d, a, 1)
-
-// 	ret := &object{
-// 		sprite:       sprite,
-// 		physicsShape: shape,
-// 	}
-
-// 	return ret
-// }
-
 func AddWall(space *cp.Space, body *cp.Body, a, b cp.Vector, radius float64) {
 	// swap so we always draw the same direction horizontally
 	if a.X < b.X {