2 files changed, 134 insertions, 1 deletions

diff --git a/src/main/java/io/github/cottonmc/cotton/gui/client/CottonHud.java b/src/main/java/io/github/cottonmc/cotton/gui/client/CottonHud.java
new file mode 100644
index 0000000..255c8bd
--- /dev/null
+++ b/src/main/java/io/github/cottonmc/cotton/gui/client/CottonHud.java
@@ -0,0 +1,109 @@
+package io.github.cottonmc.cotton.gui.client;
+
+import io.github.cottonmc.cotton.gui.widget.WWidget;
+import net.fabricmc.api.EnvType;
+import net.fabricmc.api.Environment;
+import net.fabricmc.fabric.api.client.rendering.v1.HudRenderCallback;
+import net.minecraft.client.MinecraftClient;
+import net.minecraft.client.util.Window;
+
+import java.util.*;
+
+/**
+ * Manages widgets that are painted on the in-game HUD.
+ */
+@Environment(EnvType.CLIENT)
+public enum CottonHud implements HudRenderCallback {
+	INSTANCE;
+
+	static {
+		HudRenderCallback.EVENT.register(INSTANCE);
+	}
+
+	private final Set<WWidget> widgets = new HashSet<>();
+	private final Map<WWidget, Positioner> positioners = new HashMap<>();
+
+	/**
+	 * Adds a new widget to the HUD.
+	 *
+	 * @param widget the widget
+	 */
+	public void add(WWidget widget) {
+		widgets.add(widget);
+	}
+
+	/**
+	 * Adds a new widget to the HUD with a custom positioner.
+	 *
+	 * @param widget the widget
+	 * @param positioner the positioner
+	 */
+	public void add(WWidget widget, Positioner positioner) {
+		widgets.add(widget);
+		setPositioner(widget, positioner);
+	}
+
+	/**
+	 * Sets the positioner of the widget.
+	 *
+	 * @param widget the widget
+	 * @param positioner the positioner
+	 */
+	public void setPositioner(WWidget widget, Positioner positioner) {
+		positioners.put(widget, positioner);
+	}
+
+	/**
+	 * Removes the widget from the HUD.
+	 *
+	 * @param widget the widget
+	 */
+	public void remove(WWidget widget) {
+		widgets.remove(widget);
+	}
+
+	@Override
+	public void onHudRender(float tickDelta) {
+		Window window = MinecraftClient.getInstance().getWindow();
+		int hudWidth = window.getScaledWidth();
+		int hudHeight = window.getScaledHeight();
+		for (WWidget widget : widgets) {
+			Positioner positioner = positioners.get(widget);
+			if (positioner != null) {
+				positioner.reposition(widget, hudWidth, hudHeight);
+			}
+
+			widget.paintBackground(widget.getX(), widget.getY(), -1, -1);
+		}
+	}
+
+	/**
+	 * Positioners can be used to change the position of a widget based on the window dimensions.
+	 */
+	@FunctionalInterface
+	public interface Positioner {
+		/**
+		 * Repositions the widget according to the HUD dimensions.
+		 *
+		 * @param widget the widget
+		 * @param hudWidth the width of the HUD
+		 * @param hudHeight the height of the HUD
+		 */
+		void reposition(WWidget widget, int hudWidth, int hudHeight);
+
+		/**
+		 * Creates a new positioner that offsets widgets.
+		 *
+		 * <p>If an offset is negative, the offset is subtracted from the HUD dimension on that axis.
+		 *
+		 * @param x the x offset
+		 * @param y the y offset
+		 * @return an offsetting positioner
+		 */
+		static Positioner of(int x, int y) {
+			return (widget, hudWidth, hudHeight) -> {
+				widget.setLocation((hudWidth + x) % hudWidth, (hudHeight + y) % hudHeight);
+			};
+		}
+	}
+}
diff --git a/src/main/java/io/github/cottonmc/cotton/gui/widget/WBar.java b/src/main/java/io/github/cottonmc/cotton/gui/widget/WBar.java
index 3b634b4..d3bb769 100644
--- a/src/main/java/io/github/cottonmc/cotton/gui/widget/WBar.java
+++ b/src/main/java/io/github/cottonmc/cotton/gui/widget/WBar.java
@@ -11,6 +11,8 @@ import net.minecraft.text.Text;
 import net.minecraft.text.TranslatableText;
 import net.minecraft.util.Identifier;
 
+import javax.annotation.Nullable;
+
 public class WBar extends WWidget {
 	protected final Identifier bg;
 	protected final Identifier bar;
@@ -149,7 +151,29 @@ public class WBar extends WWidget {
 	public void createPeers(GuiDescription c) {
 		if (properties==null) properties = c.getPropertyDelegate();
 	}
-	
+
+	/**
+	 * Gets the current properties of this bar.
+	 *
+	 * @return the current property delegate, or null if not initialized yet
+	 */
+	@Nullable
+	public PropertyDelegate getProperties() {
+		return properties;
+	}
+
+	/**
+	 * Sets the current properties of this bar.
+	 *
+	 * <p>This method is meant for situations when a GUI description is unavailable (such as HUDs).
+	 * {@link GuiDescription#getPropertyDelegate()} should be preferred over this if available.
+	 *
+	 * @param properties the properties
+	 */
+	public void setProperties(PropertyDelegate properties) {
+		this.properties = properties;
+	}
+
 	/**
 	 * Creates a WBar that has a constant maximum-value instead of getting the maximum from a field.
 	 * @param bg         the background image to use for the bar