1 files changed, 78 insertions, 0 deletions
diff --git a/examples/game/world.tm b/examples/game/world.tm
new file mode 100644
index 00000000..6af7cc75
--- /dev/null
+++ b/examples/game/world.tm
@@ -0,0 +1,78 @@
+
+use vectors
+
+use ./player.tm
+use ./color.tm
+use ./box.tm
+
+# Return a displacement relative to `a` that will push it out of `b`
+func solve_overlap(a_pos:Vec2, a_size:Vec2, b_pos:Vec2, b_size:Vec2)->Vec2:
+    a_left := a_pos.x
+    a_right := a_pos.x + a_size.x
+    a_top := a_pos.y
+    a_bottom := a_pos.y + a_size.y
+
+    b_left := b_pos.x
+    b_right := b_pos.x + b_size.x
+    b_top := b_pos.y
+    b_bottom := b_pos.y + b_size.y
+
+    # Calculate the overlap in each dimension
+    overlap_x := (a_right _min_ b_right) - (a_left _max_ b_left)
+    overlap_y := (a_bottom _min_ b_bottom) - (a_top _max_ b_top)
+
+    # If either axis is not overlapping, then there is no collision:
+    if overlap_x <= 0 or overlap_y <= 0:
+        return Vec2(0, 0)
+
+    if overlap_x < overlap_y:
+        if a_right > b_left and a_right < b_right:
+            return Vec2(-(overlap_x), 0)
+        else if a_left < b_right and a_left > b_left:
+            return Vec2(overlap_x, 0)
+    else:
+        if a_top < b_bottom and a_top > b_top:
+            return Vec2(0, overlap_y)
+        else if a_bottom > b_top and a_bottom < b_bottom:
+            return Vec2(0, -overlap_y)
+
+    return Vec2(0, 0)
+
+struct World(player:@Player, boxes:[@Box], dt_accum=0.0):
+    DT := 1./60.
+    CURRENT := @World(@Player(Vec2(0,0), Vec2(0,0)), [:@Box])
+    STIFFNESS := 0.3
+
+    func update(w:&World, dt:Num):
+        w.dt_accum += dt
+        while w.dt_accum > 0:
+            w:update_once()
+            w.dt_accum -= World.DT
+
+    func update_once(w:&World):
+        w.player:update()
+
+        # Resolve player overlapping with any boxes:
+        for i in 3:
+            for b in w.boxes:
+                w.player.pos += STIFFNESS * solve_overlap(w.player.pos, Player.SIZE, b.pos, b.size)
+
+    func draw(w:&World):
+        for b in w.boxes:
+            b:draw()
+        w.player:draw()
+
+    func load_map(w:&World, map:Text):
+        map = map:replace_all({$/[]/: "X", $/@{1..}/: "@", $/  /: " "})
+        w.boxes = [:@Box]
+        box_size := Vec2(50., 50.)
+        for y,line in map:lines():
+            for x,cell in line:split():
+                if cell == "X":
+                    pos := Vec2((Num(x)-1) * box_size.x, (Num(y)-1) * box_size.y)
+                    box := @Box(pos, size=box_size, color=Color.GRAY)
+                    (&w.boxes):insert(box)
+                else if cell == "@":
+                    pos := Vec2((Num(x)-1) * box_size.x, (Num(y)-1) * box_size.y)
+                    w.player = @Player(pos,pos)
+