Add state diagrams to elevator example readme file

examples/elevator/Makefile

@@ -18,6 +18,7 @@ RM_R         = rm -rf
 CP           = cp
 MKDIR_P      = mkdir -p
 DOXYGEN      = doxygen
+DOT          = dot
 
 
 SRC_DIRS     = .
@@ -26,6 +27,8 @@ INCLUDE      = -I ../../include
 SRCS         = $(wildcard $(addsuffix /*.cpp, $(SRC_DIRS)))
 OBJS         = $(SRCS:.cpp=.o)
 DEPENDS      = $(OBJS:.o=.d)
+DOT_FILES    = $(wildcard $(addsuffix /*.dot, $(SRC_DIRS)))
+PNG_FILES    = $(DOT_FILES:.dot=.png)
 
 EXE          = $(PROJECT)
 MAP          = $(PROJECT).map
@@ -80,7 +83,7 @@ LDFLAGS     += -fno-rtti
 
 .PHONY: all clean
 
-all: $(EXE)
+all: $(EXE) $(PNG_FILES)
 
 $(EXE): $(OBJS)
 	$(LD) $(OBJS) $(LDFLAGS) -o $(EXE)
@@ -89,6 +92,9 @@ $(EXE): $(OBJS)
 %.o: %.cpp
 	$(CXX) -c $(CXXFLAGS) -o $@ $<
 
+%.png: %.dot
+	$(DOT) -Tpng $^ -o $@
+
 clean:
 	$(RM) *.o
 	$(RM) *.d

examples/elevator/README.md

@@ -28,11 +28,14 @@ each other:
     - State: Moving
     - State: Panic
 
+![Elevator states](./elevator_state.png)
+
  2. Motor
     - State: Stopped
     - State: Up
     - State: Down
 
+![Machine states](./machine_state.png)
 
 A good state machine design avoids circular dependencies at all
 cost: While the elevator sends events to the motor, the motor NEVER

examples/elevator/elevator_state.dot

@@ -0,0 +1,13 @@
+digraph "G" {
+	// Colour palette from https://venngage.com/blog/color-blind-friendly-palette/
+
+	"Idle" -> "Idle" [label="Call" color="#601A4A" fontcolor="#601A4A"]
+	"Idle" -> "Moving" [label="Call" color="#601A4A" fontcolor="#601A4A"]
+	"Idle" -> "Panic" [label="Alarm" color="#EE442F" fontcolor="#EE442F"]
+
+	"Moving" -> "Panic" [label="FloorSensor" color="#63ACBE" fontcolor="#63ACBE"]
+	"Moving" -> "Idle" [label="FloorSensor" color="#63ACBE" fontcolor="#63ACBE"]
+
+	"Panic" -> "Panic" [label="Alarm" color="#EE442F" fontcolor="#EE442F"]
+
+}

examples/elevator/machine_state.dot

@@ -0,0 +1,15 @@
+digraph "G" {
+	// Colour palette from https://venngage.com/blog/color-blind-friendly-palette/
+
+	"Up" -> "Stopped" [label="MotorStop" color="#F5793A" fontcolor="#F5793A" ]
+	"Down" -> "Stopped" [label="MotorStop" color="#F5793A" fontcolor="#F5793A" ]
+	"Stopped" -> "Stopped" [label="MotorStop" color="#F5793A" fontcolor="#F5793A" ]
+
+	"Up" -> "Up" [label="MotorUp"  color="#A95AA1" fontcolor="#A95AA1" ]
+	"Down" -> "Up" [label="MotorUp" color="#A95AA1" fontcolor="#A95AA1" ]
+	"Stopped" -> "Up" [label="MotorUp" color="#A95AA1" fontcolor="#A95AA1" ]
+
+	"Up" -> "Down" [label="MotorDown" color="#0F2080" fontcolor="#0F2080" ]
+	"Down" -> "Down" [label="MotorDown" color="#0F2080" fontcolor="#0F2080" ]
+	"Stopped" -> "Down" [label="MotorDown" color="#0F2080" fontcolor="#0F2080" ]
+}