Link various screens accessible from the bridge

This kind of linking is starting to creak...

internal/ui/buttons.go

@@ -11,7 +11,9 @@ func init() {
 	registerBuilder(menus.TypeSimpleButton, registerSimpleButton)
 	registerBuilder(menus.TypeInvokeButton, registerInvokeButton)
 	registerBuilder(menus.TypeMainButton, registerMainButton)
-	registerBuilder(menus.TypeDoorHotspot, registerDebug("Unimplemented DoorHotspot", nil))
+	registerBuilder(menus.TypeDoorHotspot, registerDoorHotspot)
+	registerBuilder(menus.TypeDoorHotspot2, registerDoorHotspot)
+	registerBuilder(menus.TypeDoorHotspot3, registerDoorHotspot)
 }
 
 // A button without hover animation
@@ -79,6 +81,29 @@ func registerMainButton(d *Driver, r *menus.Record) error {
 	return nil
 }
 
+func registerDoorHotspot(d *Driver, r *menus.Record) error {
+	sprites, err := d.menu.Sprites(r.Share, 2) // base, pressed
+	if err != nil {
+		return err
+	}
+
+	btn := &button{
+		path:      r.Path(),
+		baseSpr:   sprites[0],
+		clickSpr:  sprites[1],
+		frozenSpr: sprites[0], // No disabled sprite
+		hoverImpl: hoverImpl{text: r.Text},
+	}
+
+	d.clickables = append(d.clickables, btn)
+	d.freezables = append(d.freezables, btn)
+	d.hoverables = append(d.hoverables, btn)
+	d.paintables = append(d.paintables, btn)
+
+	return nil
+
+}
+
 func registerButton(d *Driver, r *menus.Record, spriteId int) error {
 	sprites, err := d.menu.Sprites(spriteId, 3) // base, pressed, disabled
 	if err != nil {

internal/ui/driver.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"image"
 	"log"
+	"runtime/debug"
 	"strconv"
 
 	"github.com/hajimehoshi/ebiten"
@@ -24,14 +25,10 @@ func init() {
 	registerBuilder(menus.TypeLineKbd, registerDebug("Unimplemented LineKbd", nil))
 	registerBuilder(menus.TypeDialogue, registerDebug("Unimplemented Dialogue", nil))
 
-	// Needed for Arrange.mnu (???)
-	registerBuilder(menus.TypeSquadButton, registerDebug("Unimplemented SquadButton", nil))
-
 	// Needed for Briefing.mnu
 	registerBuilder(menus.TypeLineBriefing, registerDebug("Unimplemented LineBriefing", nil))
 
 	// Needed for ChaEquip.mnu
-	registerBuilder(menus.TypeUnknown1, registerDebug("Unimplemented Unknown1", nil))
 	registerBuilder(menus.TypeThumb, registerDebug("Unimplemented Thumb", nil))
 
 	// Needed for MainGameChaos.mnu
@@ -226,6 +223,11 @@ func (d *Driver) SetValueInt(id string, value int) error {
 }
 
 func (d *Driver) Update(screenX, screenY int) error {
+	if d == nil {
+		debug.PrintStack()
+		return fmt.Errorf("Tried to update a nil ui.Driver")
+	}
+
 	// This will be updated while processing hovers
 	d.tooltip = ""
 	d.ticks += 1
@@ -274,6 +276,11 @@ func (d *Driver) Update(screenX, screenY int) error {
 }
 
 func (d *Driver) Draw(screen *ebiten.Image) error {
+	if d == nil {
+		debug.PrintStack()
+		return fmt.Errorf("Tried to draw a nil ui.Driver")
+	}
+
 	var do ebiten.DrawImageOptions
 
 	for _, paint := range d.paintables {

internal/ui/noninteractive.go

@@ -15,7 +15,7 @@ func init() {
 	registerBuilder(menus.TypeHypertext, registerHypertext)
 	registerBuilder(menus.TypeOverlay, registerOverlay)
 	registerBuilder(menus.TypeAnimationSample, registerAnimation)
-	registerBuilder(menus.TypeAnimationHover, registerDebug("WIP AnimationHover", registerAnimationHover))
+	registerBuilder(menus.TypeAnimationHover, registerAnimationHover)
 }
 
 // A non-interactive element is not a widget; it merely displays some pixels and