Tweak emitters so their wire state is more clear.

This has become a problem in the presence of bombs.

game.scm

@@ -371,11 +371,17 @@
 (define (draw-brick pos)
   (draw-tile context tileset 22 (vec2-x pos) (vec2-y pos)))
 
-(define (draw-clock-emitter pos)
-  (draw-tile context tileset 48 (vec2-x pos) (vec2-y pos)))
+(define (draw-clock-emitter pos state)
+  (draw-tile context tileset 48 (vec2-x pos) (vec2-y pos))
+  (set-global-alpha! context 0.5)
+  (draw-wire-state pos state)
+  (set-global-alpha! context 1.0))
 
-(define (draw-switched-emitter pos on?)
-  (draw-tile context tileset (if on? 48 47) (vec2-x pos) (vec2-y pos)))
+(define (draw-switched-emitter pos state)
+  (draw-tile context tileset (if state 48 47) (vec2-x pos) (vec2-y pos))
+  (set-global-alpha! context 0.5)
+  (draw-wire-state pos state)
+  (set-global-alpha! context 1.0))
 
 (define (draw-floor-switch pos on?)
   (draw-tile context tileset (if on? 25 24) (vec2-x pos) (vec2-y pos)))
@@ -420,8 +426,8 @@
     (('wall pos type) (draw-wall pos type))
     (('block pos type) (draw-block pos type))
     (('brick pos) (draw-brick pos))
-    (('clock-emitter pos) (draw-clock-emitter pos))
-    (('switched-emitter pos on?) (draw-switched-emitter pos on?))
+    (('clock-emitter pos state) (draw-clock-emitter pos state))
+    (('switched-emitter pos state) (draw-switched-emitter pos state))
     (('floor-switch pos on?) (draw-floor-switch pos on?))
     (('bomb pos countdown) (draw-bomb pos countdown))
     (('gem pos) (draw-gem pos))

modules/game/actors.scm

@@ -165,43 +165,50 @@
     (('pushed?) ($ pushed?))))
 
 (define (^clock-emitter bcom x y interval)
-  (define timer (spawn ^cell -1))
+  (define timer (spawn ^cell 0))
   (define position (vector x y 0))
-  (match-lambda*
-    (('type) 'emitter)
-    (('position) position)
-    (('tick grid-info)
-     (let ((t (modulo (+ ($ timer) 1) interval)))
-       ($ timer t)
-       (when (= t 0)
-         ($ grid-info 'append-event `(emit ,x ,y)))))
-    (('post-tick grid-info) #f)
-    (('enter obj grid-info) #f)
-    (('exit obj grid-info) #f)
-    (('wire-state grid-info from from-x from-y)
+  (define (wire-state)
     (match ($ timer)
       (0 'electron-head)
       (1 'electron-tail)
       (_ 'copper)))
+  (match-lambda*
+    (('type) 'emitter)
+    (('position) position)
+    (('tick grid-info) #f)
+    (('post-tick grid-info)
+     (let ((t (modulo (+ ($ timer) 1) interval)))
+       ($ timer t)
+       (when (= t 1)
+         ($ grid-info 'append-event `(emit ,x ,y)))))
+    (('enter obj grid-info) #f)
+    (('exit obj grid-info) #f)
+    (('wire-state grid-info from from-x from-y) (wire-state))
     (('update-wire-state grid-info neighbor-grid) #f)
     (('alive?) #t)
-    (('describe) `(clock-emitter ,position))
+    (('describe) `(clock-emitter ,position ,(wire-state)))
     (('collide other offset grid-info) #f)))
 
 (define (^switched-emitter bcom x y interval)
-  (define timer (spawn ^cell -1))
+  (define timer (spawn ^cell 0))
   (define on? (spawn ^cell))
   (define position (vector x y 0))
+  (define (wire-state)
+    (and ($ on?)
+         (match ($ timer)
+           (0 'electron-head)
+           (1 'electron-tail)
+           (_ 'copper))))
   (match-lambda*
     (('type) 'switched-emitter)
     (('position) position)
-    (('tick grid-info)
+    (('tick grid-info) #f)
+    (('post-tick grid-info)
      (when ($ on?)
        (let ((t (modulo (+ ($ timer) 1) interval)))
          ($ timer t)
-         (when (= t 0)
+         (when (= t 1)
            ($ grid-info 'append-event `(emit ,x ,y))))))
-    (('post-tick grid-info) #f)
     (('enter obj grid-info) #f)
     (('exit obj grid-info) #f)
     (('activate grid-info)
@@ -211,16 +218,11 @@
     (('deactivate grid-info)
      ($ on? #f)
      ($ grid-info 'append-event `(emitter-off ,x ,y)))
-    (('wire-state grid-info from from-x from-y)
-     (and ($ on?)
-          (match ($ timer)
-            (0 'electron-head)
-            (1 'electron-tail)
-            (_ 'copper))))
+    (('wire-state grid-info from from-x from-y) (wire-state))
     (('update-wire-state grid-info neighbor-grid) #f)
     (('alive?) #t)
     (('on?) ($ on?))
-    (('describe) `(switched-emitter ,position ,($ on?)))
+    (('describe) `(switched-emitter ,position ,(wire-state)))
     (('collide other offset grid-info) #f)))
 
 (define (first-non-player-occupant grid-info x y)

modules/game/levels/level-4.tmx

@@ -62,7 +62,7 @@
   </object>
   <object id="22" type="clock-emitter" gid="49" x="32" y="144" width="16" height="16">
    <properties>
-    <property name="interval" type="int" value="1"/>
+    <property name="interval" type="int" value="3"/>
    </properties>
   </object>
   <object id="23" type="switched-emitter" gid="48" x="80" y="112" width="16" height="16">