up3

server/block/cube/trace/entity.go

@@ -0,0 +1,51 @@
+package trace
+
+import (
+	"github.com/df-mc/dragonfly/server/block/cube"
+	"github.com/df-mc/dragonfly/server/world"
+	"github.com/go-gl/mathgl/mgl64"
+)
+
+// EntityResult is the result of a ray trace collision with an entities bounding box.
+type EntityResult struct {
+	bb   cube.BBox
+	pos  mgl64.Vec3
+	face cube.Face
+
+	entity world.Entity
+}
+
+// BBox returns the entities bounding box that was collided with.
+func (r EntityResult) BBox() cube.BBox {
+	return r.bb
+}
+
+// Position ...
+func (r EntityResult) Position() mgl64.Vec3 {
+	return r.pos
+}
+
+// Face ...
+func (r EntityResult) Face() cube.Face {
+	return r.face
+}
+
+// Entity returns the entity that was collided with.
+func (r EntityResult) Entity() world.Entity {
+	return r.entity
+}
+
+// EntityIntercept performs a ray trace and calculates the point on the entities bounding box's edge nearest to the start position
+// that the ray collided with.
+// EntityIntercept returns an EntityResult with the entity collided with and with the colliding vector closest to the start position,
+// if no colliding point was found, a zero BlockResult is returned ok is false.
+func EntityIntercept(e world.Entity, start, end mgl64.Vec3) (result EntityResult, ok bool) {
+	bb := e.H().Type().BBox(e).Translate(e.Position()).Grow(0.3)
+
+	r, ok := BBoxIntercept(bb, start, end)
+	if !ok {
+		return
+	}
+
+	return EntityResult{bb: bb, pos: r.Position(), face: r.Face(), entity: e}, true
+}