examples: Add Allegro 5 example

Author: dkl

examples/graphics/Allegro5/hello.bas

@@ -0,0 +1,47 @@
+'' Allegro5 example, based on the Allegro5 documentation
+
+#include "allegro5/allegro.bi"
+#include "allegro5/allegro_font.bi"
+#include "allegro5/allegro_ttf.bi"
+
+var TTF_FONT = exepath() + "/../SDL/data/Vera.ttf"
+
+al_init()
+al_init_font_addon()
+al_init_ttf_addon()
+
+var display = al_create_display(640, 480)
+if display = NULL then
+	print "al_create_display() failed"
+	end 1
+end if
+
+var font = al_load_ttf_font(TTF_FONT, 24, 0)
+if font = NULL then
+	print "al_load_ttf_font() failed"
+	end 1
+end if
+
+var eventqueue = al_create_event_queue()
+al_install_keyboard()
+al_register_event_source(eventqueue, al_get_display_event_source(display))
+al_register_event_source(eventqueue, al_get_keyboard_event_source())
+
+do
+	al_clear_to_color(al_map_rgb(0,0,255))
+	al_draw_text(font, al_map_rgb(255,255,255), 100, 100, 0, "Hello!")
+	al_draw_text(font, al_map_rgb(0,255,0), 100, 200, 0, "Press any key to exit.")
+
+	al_flip_display()
+
+	dim event as ALLEGRO_EVENT
+	al_wait_for_event(eventqueue, @event)
+
+	select case event.type
+	case ALLEGRO_EVENT_KEY_DOWN, ALLEGRO_EVENT_DISPLAY_CLOSE
+		exit do
+	end select
+loop
+
+al_destroy_event_queue(eventqueue)
+al_destroy_display(display)