From 0387e313de874d63e535fd95a41717c4c871a862 Mon Sep 17 00:00:00 2001
From: Sander Schobers <sander@schobers.eu>
Date: Wed, 6 Mar 2019 18:18:35 +0100
Subject: [PATCH] Added user events & possibility to 'refresh'. - Refresh
 unblocks event loop for the next redraw.

---
 allg5/event.go         | 43 +++++++++++++++++++++++++++++++++++++++++-
 ui/allg5ui/renderer.go | 17 ++++++++++++++++-
 ui/renderer.go         |  1 +
 3 files changed, 59 insertions(+), 2 deletions(-)

diff --git a/allg5/event.go b/allg5/event.go
index caaea3f..f4505c4 100644
--- a/allg5/event.go
+++ b/allg5/event.go
@@ -1,6 +1,15 @@
 package allg5
 
-// #include <allegro5/allegro.h>
+/*
+#include <allegro5/allegro.h>
+
+#define USER_EVENT_TYPE ALLEGRO_GET_EVENT_TYPE('u', 's', 'e', 'r')
+
+void init_user_event(ALLEGRO_EVENT* e)
+{
+	e->user.type = USER_EVENT_TYPE;
+}
+*/
 import "C"
 
 import (
@@ -117,6 +126,14 @@ type MouseMoveEvent struct {
 	Pressure       float32
 }
 
+type UserEvent struct {
+	EventBase
+}
+
+type UserEventSource struct {
+	source *C.ALLEGRO_EVENT_SOURCE
+}
+
 func NewEventQueue() (*EventQueue, error) {
 	q := C.al_create_event_queue()
 	if q == nil {
@@ -141,6 +158,10 @@ func (eq *EventQueue) RegisterKeyboard() {
 	eq.register(C.al_get_keyboard_event_source())
 }
 
+func (eq *EventQueue) RegisterUserEvents(source *UserEventSource) {
+	eq.register(source.source)
+}
+
 func (eq *EventQueue) mapEvent(e *C.ALLEGRO_EVENT) Event {
 	any := (*C.ALLEGRO_ANY_EVENT)(unsafe.Pointer(e))
 	eb := EventBase{float64(any.timestamp)}
@@ -172,6 +193,8 @@ func (eq *EventQueue) mapEvent(e *C.ALLEGRO_EVENT) Event {
 	case C.ALLEGRO_EVENT_KEY_CHAR:
 		key := (*C.ALLEGRO_KEYBOARD_EVENT)(unsafe.Pointer(e))
 		return &KeyCharEvent{KeyEvent{eb, Key(key.keycode), nil}, rune(key.unichar), KeyMod(key.modifiers), bool(key.repeat)}
+	case C.USER_EVENT_TYPE:
+		return &UserEvent{eb}
 	}
 	return nil
 }
@@ -193,3 +216,21 @@ func (eq *EventQueue) GetWait() Event {
 func (eq *EventQueue) Destroy() {
 	C.al_destroy_event_queue(eq.queue)
 }
+
+func NewUserEventSource() *UserEventSource {
+	s := (*C.ALLEGRO_EVENT_SOURCE)(C.malloc(C.sizeof_ALLEGRO_EVENT_SOURCE))
+	source := &UserEventSource{s}
+	C.al_init_user_event_source(s)
+	return source
+}
+
+func (s *UserEventSource) Destroy() {
+	C.al_destroy_user_event_source(s.source)
+	C.free(unsafe.Pointer(s.source))
+}
+
+func (s *UserEventSource) EmitEvent() bool {
+	e := (*C.ALLEGRO_EVENT)(C.malloc(C.sizeof_ALLEGRO_EVENT))
+	C.init_user_event(e)
+	return bool(C.al_emit_user_event(s.source, e, nil))
+}
diff --git a/ui/allg5ui/renderer.go b/ui/allg5ui/renderer.go
index ec48ca6..72aa33e 100644
--- a/ui/allg5ui/renderer.go
+++ b/ui/allg5ui/renderer.go
@@ -28,11 +28,13 @@ func NewRenderer(w, h int, opts allg5.NewDisplayOptions) (*Renderer, error) {
 		return nil, err
 	}
 
+	user := allg5.NewUserEventSource()
 	eq.RegisterKeyboard()
 	eq.RegisterMouse()
 	eq.RegisterDisplay(disp)
+	eq.RegisterUserEvents(user)
 
-	return &Renderer{disp, eq, map[string]*font{}}, nil
+	return &Renderer{disp, eq, map[string]*font{}, user}, nil
 }
 
 // Renderer implements ui.Renderer using Allegro 5.
@@ -40,6 +42,7 @@ type Renderer struct {
 	disp *allg5.Display
 	eq   *allg5.EventQueue
 	ft   map[string]*font
+	user *allg5.UserEventSource
 }
 
 // Renderer implementation (events)
@@ -60,14 +63,21 @@ func (r *Renderer) PushEvents(t ui.EventTarget, wait bool) {
 			t.Handle(&ui.MouseButtonUpEvent{MouseEvent: mouseEvent(e.MouseEvent), Button: ui.MouseButton(e.Button)})
 		case *allg5.MouseMoveEvent:
 			t.Handle(&ui.MouseMoveEvent{MouseEvent: mouseEvent(e.MouseEvent), MouseWheel: float32(e.DeltaZ)})
+		case *allg5.UserEvent:
+			// used to unblock the wait for events.
 		}
 		ev = r.eq.Get()
 	}
 }
 
+func (r *Renderer) Refresh() {
+	r.user.EmitEvent()
+}
+
 // Renderer implementation (lifetime)
 
 func (r *Renderer) Destroy() error {
+	r.user.Destroy()
 	r.eq.Destroy()
 	r.disp.Destroy()
 	return nil
@@ -168,6 +178,11 @@ func (r *Renderer) Size() geom.PointF32 {
 	return geom.PtF32(float32(r.disp.Width()), float32(r.disp.Height()))
 }
 
+func (r *Renderer) SetIcon(im ui.Image) {
+	bmp := r.mustGetBitmap(im)
+	r.disp.SetIcon(bmp)
+}
+
 func (r *Renderer) SetWindowTitle(t string) {
 	r.disp.SetWindowTitle(t)
 }
diff --git a/ui/renderer.go b/ui/renderer.go
index b2f9138..b90a654 100644
--- a/ui/renderer.go
+++ b/ui/renderer.go
@@ -10,6 +10,7 @@ import (
 type Renderer interface {
 	// Events
 	PushEvents(t EventTarget, wait bool)
+	Refresh()
 
 	// Lifetime
 	Destroy() error