Merge ra4king#94: Call floating wires "z" instead of "x"

docs/docs/wires/wire-colors.md

@@ -28,38 +28,37 @@ light green wire - 1-bit wire with value of 1
 
 ![pt-1-light-green-wire]
 
-### Part 2: Blue
+### Part 2: Light Blue / Dark Blue
 
-blue indicates an unitialized 1-bit wire
+Light blue indicates a 1-bit wire that is "floating" or in a "high impedance
+state" — in other words, the wire is not connected to anything.
 
-The wire below is unitialized because no value is being driven onto it.
+The wire below is floating because no value is being driven onto it.
 
 ![pt-2-blue-wire]
 
-Since you may have both initialized and unitialized wires in a 
-properly functioning circuit, an unitialized wire is not considered an error.
+Dark blue indicates a floating multi-bit wire.
 
+![pt-3-dark-blue-wire-uninit]
+
+Since you may have both floating wires and wires with 0/1 on them in a properly
+functioning circuit, a floating wire is not considered an error.
 
 ### Part 3: Black
 
-black indicates either an initialized or unitialized multi-bit wire
+Black indicates a multi-bit wire carrying no floating values (only 0s and 1s).
 
-black wire - multi-bit wire, initialized
+Black wire - multi-bit wire carrying only 0s and 1s:
 
 ![pt-3-black-wire]
 
-black wire - multi-bit wire, unitialized
-
-![pt-3-black-wire-unint]
-
-Also note that a multi-bit wire can have both initialized and unitialized bits.
-This error usually pops up when you combine wires together with a splitter, and
-some of the individual wires that make up the multi-bit wire are unitialized.
-
-As stated above, since you may have both initialized and unitialized wires in a 
-properly functioning circuit, an unitialized wire is not considered an error.
-
+Also note that a multi-bit wire can carry both floating and 0/1 bits.
+This usually pops up when you combine wires together with a splitter, and
+some of the individual wires that make up the multi-bit wire are floating.
 
+As stated above, since you may have both floating wires and wires with 0/1 on
+them in a properly functioning circuit, a floating wire is not considered an
+error.
 
 ## Error State Wires
 
@@ -101,6 +100,6 @@ These multi-bit wires are known as "wire bundles" in industry.
 [pt-1-dark-green-wire]: img/wire-colors-pt-1-dark-green-wire.PNG "dark green CircuitSim wire"
 [pt-2-blue-wire]: img/wire-colors-pt-2-blue-wire.PNG "blue CircuitSim wire"
 [pt-3-black-wire]: img/wire-colors-pt-3-black-wire.PNG "black CircuitSim wire"
-[pt-3-black-wire-unint]: img/wire-colors-pt-3-black-wire-uninit.PNG "black CircuitSim wire uninitialized"
+[pt-3-dark-blue-wire-uninit]: img/wire-colors-pt-3-dark-blue-wire-uninit.PNG "dark blue CircuitSim wire"
 [pt-4-orange-wire]: img/wire-colors-pt-4-orange-wire.PNG "orange CircuitSim wire"
 [pt-5-red-wire]: img/wire-colors-pt-5-red-wire.PNG "red CircuitSim wire"

src/main/java/com/ra4king/circuitsim/gui/GuiUtils.java

@@ -220,7 +220,7 @@ public static void setBitColor(GraphicsContext graphics, CircuitState circuitSta
 					setBitColor(graphics, circuitState.getMergedValue(link));
 				}
 			} else {
-				setBitColor(graphics, State.X);
+				setBitColor(graphics, State.Z);
 			}
 		} else {
 			graphics.setStroke(Color.ORANGE);
@@ -230,8 +230,8 @@ public static void setBitColor(GraphicsContext graphics, CircuitState circuitSta
 
 	private static final Color ONE_COLOR = Color.GREEN.brighter();
 	private static final Color ZERO_COLOR = Color.GREEN.darker();
-	private static final Color X_1BIT_COLOR = Color.BLUE;
-	private static final Color X_MULTIBIT_COLOR = Color.BLUE.darker();
+	private static final Color Z_1BIT_COLOR = Color.BLUE;
+	private static final Color Z_MULTIBIT_COLOR = Color.BLUE.darker();
 
 	public static void setBitColor(GraphicsContext graphics, WireValue value) {
 		if (value.getBitSize() == 1) {
@@ -240,8 +240,8 @@ public static void setBitColor(GraphicsContext graphics, WireValue value) {
 			graphics.setStroke(Color.BLACK);
 			graphics.setFill(Color.BLACK);
 		} else {
-			graphics.setStroke(X_MULTIBIT_COLOR);
-			graphics.setFill(X_MULTIBIT_COLOR);
+			graphics.setStroke(Z_MULTIBIT_COLOR);
+			graphics.setFill(Z_MULTIBIT_COLOR);
 		}
 	}
 
@@ -255,9 +255,9 @@ public static void setBitColor(GraphicsContext graphics, State bitState) {
 				graphics.setStroke(ZERO_COLOR);
 				graphics.setFill(ZERO_COLOR);
 			}
-			case X -> {
-				graphics.setStroke(X_1BIT_COLOR);
-				graphics.setFill(X_1BIT_COLOR);
+			case Z -> {
+				graphics.setStroke(Z_1BIT_COLOR);
+				graphics.setFill(Z_1BIT_COLOR);
 			}
 		}
 	}

src/main/java/com/ra4king/circuitsim/simulator/CircuitState.java

@@ -353,7 +353,7 @@ void link(LinkState other) {
 
 			cachedMergedValue = null;
 			isShortCircuited = null;
-			participants.forEach((port, info) -> info.lastPropagated.setAllBits(State.X));
+			participants.forEach((port, info) -> info.lastPropagated.setAllBits(State.Z));
 
 			linkStates.remove(other.link);
 			getCircuit().getSimulator().linkRemoved(other.link);

src/main/java/com/ra4king/circuitsim/simulator/WireValue.java

@@ -7,7 +7,7 @@
  */
 public class WireValue {
 	public enum State {
-		ONE('1'), ZERO('0'), X('x');
+		ONE('1'), ZERO('0'), Z('z');
 
 		public final char repr;
 
@@ -16,14 +16,14 @@ public enum State {
 		}
 
 		public State negate() {
-			return this == X ? X : this == ONE ? ZERO : ONE;
+			return this == Z ? Z : this == ONE ? ZERO : ONE;
 		}
 	}
 
 	private State[] bits;
 
 	public WireValue(int bitSize) {
-		this(bitSize, State.X);
+		this(bitSize, State.Z);
 	}
 
 	public WireValue(int bitSize, State state) {
@@ -53,9 +53,9 @@ public WireValue merge(WireValue value) {
 		}
 
 		for (int i = 0; i < getBitSize(); i++) {
-			if (getBit(i) == State.X) {
+			if (getBit(i) == State.Z) {
 				setBit(i, value.getBit(i));
-			} else if (value.getBit(i) == State.X) {
+			} else if (value.getBit(i) == State.Z) {
 				setBit(i, getBit(i));
 			} else if (value.getBit(i) != getBit(i)) {
 				throw new ShortCircuitException(this, value);
@@ -81,7 +81,7 @@ public void setBitSize(int bitSize) {
 		State[] oldBits = bits;
 
 		bits = new State[bitSize];
-		setAllBits(State.X);
+		setAllBits(State.Z);
 		System.arraycopy(oldBits, 0, bits, 0, Math.min(bitSize, oldBits.length));
 	}
 
@@ -129,7 +129,7 @@ public boolean isValidValue() {
 		}
 
 		for (State bit : bits) {
-			if (bit == State.X) {
+			if (bit == State.Z) {
 				return false;
 			}
 		}
@@ -140,7 +140,7 @@ public boolean isValidValue() {
 	public int getValue() {
 		int value = 0;
 		for (int i = 0; i < bits.length; i++) {
-			if (bits[i] == State.X) {
+			if (bits[i] == State.Z) {
 				throw new IllegalStateException("Invalid value");
 			}
 
@@ -153,29 +153,29 @@ public int getValue() {
 	 * Converts the value held on this wire to a hex string.
 	 *
 	 * @return a lowercase hex string if all bits are defined, otherwise
-	 * getBitSize() 'x's
+	 * getBitSize() 'z's
 	 */
 	public String toHexString() {
 		int hexDigits = 1 + (getBitSize() - 1) / 4;
 		if (isValidValue()) {
 			return String.format("%0" + hexDigits + "x", getValue());
 		} else {
-			return "x".repeat(Math.max(0, hexDigits));
+			return "z".repeat(Math.max(0, hexDigits));
 		}
 	}
 
 	/**
 	 * Converts the value held on this wire to a decimal string.
 	 *
 	 * @return a decimal string if all bits are defined, otherwise
-	 * getBitSize() 'x's
+	 * getBitSize() 'z's
 	 */
 	public String toDecString() {
 		int decDigits = (int)Math.ceil(getBitSize() / 3.322);
 		if (isValidValue()) {
 			return String.format("%0" + decDigits + "d", getValue());
 		} else {
-			return "x".repeat(Math.max(0, decDigits));
+			return "z".repeat(Math.max(0, decDigits));
 		}
 	}
 

src/main/java/com/ra4king/circuitsim/simulator/components/arithmetic/Comparator.java

@@ -46,7 +46,7 @@ public void valueChanged(CircuitState state, WireValue value, int portIndex) {
 			state.pushValue(getPort(PORT_EQ), new WireValue(1, valueA == valueB ? State.ONE : State.ZERO));
 			state.pushValue(getPort(PORT_GT), new WireValue(1, valueA > valueB ? State.ONE : State.ZERO));
 		} else {
-			WireValue xValue = new WireValue(1, State.X);
+			WireValue xValue = new WireValue(1, State.Z);
 			state.pushValue(getPort(PORT_LT), xValue);
 			state.pushValue(getPort(PORT_EQ), xValue);
 			state.pushValue(getPort(PORT_GT), xValue);

src/main/java/com/ra4king/circuitsim/simulator/components/gates/ControlledBuffer.java

@@ -9,15 +9,15 @@
  * @author Roi Atalla
  */
 public class ControlledBuffer extends Component {
-	private final WireValue X_VALUE;
+	private final WireValue Z_VALUE;
 
 	public static final int PORT_IN = 0;
 	public static final int PORT_ENABLE = 1;
 	public static final int PORT_OUT = 2;
 
 	public ControlledBuffer(String name, int bitSize) {
 		super(name, new int[] { bitSize, 1, bitSize });
-		X_VALUE = new WireValue(bitSize);
+		Z_VALUE = new WireValue(bitSize);
 	}
 
 	@Override
@@ -29,7 +29,7 @@ public void valueChanged(CircuitState state, WireValue value, int portIndex) {
 		if (state.getLastReceived(getPort(PORT_ENABLE)).getBit(0) == State.ONE) {
 			state.pushValue(getPort(PORT_OUT), state.getLastReceived(getPort(PORT_IN)));
 		} else {
-			state.pushValue(getPort(PORT_OUT), X_VALUE);
+			state.pushValue(getPort(PORT_OUT), Z_VALUE);
 		}
 	}
 }

src/main/java/com/ra4king/circuitsim/simulator/components/gates/Gate.java

@@ -71,20 +71,20 @@ public void valueChanged(CircuitState state, WireValue value, int portIndex) {
 			}
 
 			result.setBit(bit, portBit);
-			boolean isX = result.getBit(bit) == State.X;
+			boolean isX = result.getBit(bit) == State.Z;
 
 			for (int port = 1; port < numInputs; port++) {
 				portBit = state.getLastReceived(getPort(port)).getBit(bit);
 				if (negateInputs[port]) {
 					portBit = portBit.negate();
 				}
 
-				isX &= portBit == State.X;
+				isX &= portBit == State.Z;
 				result.setBit(bit, operate(result.getBit(bit), portBit));
 			}
 
 			if (isX) {
-				result.setBit(bit, State.X);
+				result.setBit(bit, State.Z);
 			} else if (negateOutput) {
 				result.setBit(bit, result.getBit(bit) == State.ONE ? State.ZERO : State.ONE);
 			}

src/main/java/com/ra4king/circuitsim/simulator/components/gates/XorGate.java

@@ -24,6 +24,6 @@ protected XorGate(String name, int bitSize, int numInputs, boolean[] negateInput
 
 	@Override
 	protected State operate(State acc, State bit) {
-		return acc != State.X && bit != State.X && acc != bit ? State.ONE : State.ZERO;
+		return acc != State.Z && bit != State.Z && acc != bit ? State.ONE : State.ZERO;
 	}
 }

src/main/java/com/ra4king/circuitsim/simulator/components/memory/DFlipFlop.java

@@ -49,7 +49,7 @@ public void valueChanged(CircuitState state, WireValue value, int portIndex) {
 			pushValue(state, State.ONE);
 		} else if (enable != State.ZERO && portIndex == PORT_CLOCK && value.getBit(0) == State.ONE) {
 			State d = state.getLastReceived(getPort(PORT_D)).getBit(0);
-			if (d != State.X) {
+			if (d != State.Z) {
 				pushValue(state, d);
 			}
 		}

src/main/java/com/ra4king/circuitsim/simulator/components/plexers/PriorityEncoder.java

@@ -42,7 +42,7 @@ public void valueChanged(CircuitState state, WireValue value, int portIndex) {
 		// The only other input Port are the indexed inputs
 		if (!this.isEnabled) {
 			state.pushValue(getEnabledOutPort(), new WireValue(1, State.ZERO));
-			state.pushValue(out, new WireValue(out.getLink().getBitSize(), State.X));
+			state.pushValue(out, new WireValue(out.getLink().getBitSize(), State.Z));
 			state.pushValue(getGroupSignalPort(), new WireValue(1, State.ZERO));
 			return;
 		}
@@ -59,7 +59,7 @@ public void valueChanged(CircuitState state, WireValue value, int portIndex) {
 
 		if (highest == -1) {
 			state.pushValue(getEnabledOutPort(), new WireValue(1, State.ONE));
-			state.pushValue(out, new WireValue(out.getLink().getBitSize(), State.X));
+			state.pushValue(out, new WireValue(out.getLink().getBitSize(), State.Z));
 			state.pushValue(getGroupSignalPort(), new WireValue(1, State.ZERO));
 
 		} else {

src/main/java/com/ra4king/circuitsim/simulator/components/wiring/SimpleTransistor.java

@@ -93,7 +93,7 @@ public class SimpleTransistor extends Component {
 	public static final int PORT_GATE = 1;
 	public static final int PORT_DRAIN = 2;
 
-	private static final WireValue X_VALUE = new WireValue(1);
+	private static final WireValue Z_VALUE = new WireValue(1);
 
 	private boolean isIllegallyWired;
 	private boolean isPType;
@@ -124,7 +124,7 @@ public void valueChanged(CircuitState state, WireValue value, int portIndex) {
 		if (pTypeOk && nTypeOk && state.getLastReceived(getPort(PORT_GATE)).getBit(0) == enableBit) {
 			state.pushValue(getPort(PORT_DRAIN), new WireValue(sourceBit));
 		} else {
-			state.pushValue(getPort(PORT_DRAIN), X_VALUE);
+			state.pushValue(getPort(PORT_DRAIN), Z_VALUE);
 
 			if (!nTypeOk) {
 				throw new SimulationException("N-type transistor must not be connected to logic-level high!");

src/main/java/com/ra4king/circuitsim/simulator/components/wiring/Transistor.java

@@ -13,7 +13,7 @@ public class Transistor extends Component {
 	public static final int PORT_GATE = 1;
 	public static final int PORT_OUT = 2;
 
-	private static final WireValue X_VALUE = new WireValue(1);
+	private static final WireValue Z_VALUE = new WireValue(1);
 
 	private State enableBit;
 
@@ -32,7 +32,7 @@ public void valueChanged(CircuitState state, WireValue value, int portIndex) {
 		if (state.getLastReceived(getPort(PORT_GATE)).getBit(0) == enableBit) {
 			state.pushValue(getPort(PORT_OUT), state.getLastReceived(getPort(PORT_IN)));
 		} else {
-			state.pushValue(getPort(PORT_OUT), X_VALUE);
+			state.pushValue(getPort(PORT_OUT), Z_VALUE);
 		}
 	}
 }

src/test/java/com/ra4king/circuitsim/simulator/WireValueTest.java

@@ -15,7 +15,7 @@ public class WireValueTest {
 	public void testBasic() {
 		WireValue value = new WireValue(10);
 		assertThat(value.getBitSize()).isEqualTo(10);
-		assertThat(WireValueUtils.allBitsEqualTo(value, State.X)).isTrue();
+		assertThat(WireValueUtils.allBitsEqualTo(value, State.Z)).isTrue();
 
 		value = new WireValue(15, State.ONE);
 		assertThat(value.getBitSize()).isEqualTo(15);
@@ -44,7 +44,7 @@ public void testMerge() {
 		value2.setBit(2, State.ZERO);
 
 		WireValue merge = new WireValue(value1).merge(value2);
-		assertThat(WireValueUtils.allBitsEqualTo(merge, State.ONE, State.ZERO, State.ZERO, State.X)).isTrue();
+		assertThat(WireValueUtils.allBitsEqualTo(merge, State.ONE, State.ZERO, State.ZERO, State.Z)).isTrue();
 	}
 
 	@Test