Added an options button. It doesn't do much, yet...

src/main/java/com/minelittlepony/unicopia/UnicopiaClient.java

@@ -1,5 +1,6 @@
 package com.minelittlepony.unicopia;
 
+import java.util.List;
 import java.util.UUID;
 
 import javax.annotation.Nullable;
@@ -12,14 +13,23 @@ import com.minelittlepony.unicopia.network.MsgRequestCapabilities;
 import com.minelittlepony.unicopia.player.IPlayer;
 import com.minelittlepony.unicopia.player.IView;
 import com.minelittlepony.unicopia.player.PlayerSpeciesList;
+import com.minelittlepony.util.gui.ButtonGridLayout;
+import com.minelittlepony.util.gui.UButton;
 
 import net.minecraft.client.Minecraft;
+import net.minecraft.client.audio.PositionedSoundRecord;
 import net.minecraft.client.entity.EntityPlayerSP;
+import net.minecraft.client.gui.GuiButton;
+import net.minecraft.client.gui.GuiOptions;
+import net.minecraft.client.gui.GuiScreen;
+import net.minecraft.client.resources.I18n;
 import net.minecraft.entity.player.EntityPlayer;
+import net.minecraft.init.SoundEvents;
 import net.minecraft.world.IInteractionObject;
 import net.minecraftforge.client.event.ColorHandlerEvent;
 import net.minecraftforge.client.event.EntityViewRenderEvent;
 import net.minecraftforge.client.event.FOVUpdateEvent;
+import net.minecraftforge.client.event.GuiScreenEvent;
 import net.minecraftforge.client.event.RenderGameOverlayEvent;
 import net.minecraftforge.client.event.RenderGameOverlayEvent.ElementType;
 import net.minecraftforge.client.event.RenderLivingEvent;
@@ -32,6 +42,8 @@ import net.minecraftforge.fml.common.gameevent.TickEvent.Phase;
 import net.minecraftforge.fml.relauncher.Side;
 import net.minecraftforge.fml.relauncher.SideOnly;
 
+import static com.minelittlepony.util.gui.ButtonGridLayout.*;
+
 @EventBusSubscriber(Side.CLIENT)
 public class UnicopiaClient extends UClient {
 
@@ -55,6 +67,7 @@ public class UnicopiaClient extends UClient {
             }
         }
 
+
         return UConfig.getInstance().getPrefferedRace();
     }
 
@@ -106,6 +119,44 @@ public class UnicopiaClient extends UClient {
         return Minecraft.getMinecraft().gameSettings.thirdPersonView;
     }
 
+    @SideOnly(Side.CLIENT)
+    @SubscribeEvent
+    public static void onDisplayGui(GuiScreenEvent.InitGuiEvent.Post event) {
+        if (event.getGui() instanceof GuiOptions) {
+            addUniButton(event);
+        }
+    }
+
+    static void addUniButton(GuiScreenEvent.InitGuiEvent.Post event) {
+        ButtonGridLayout layout = new ButtonGridLayout(event.getButtonList());
+
+        GuiButton uni = new UButton(layout.getNextButtonId(), 0, 0, 150, 20, I18n.format("gui.unicopia"), b -> {
+            Minecraft.getMinecraft().getSoundHandler().playSound(PositionedSoundRecord.getMasterRecord(SoundEvents.BLOCK_ANVIL_USE, 1));
+            b.displayString = "<< WIP >>";
+
+            return false;
+        });
+
+        List<Integer> possibleXCandidates = list(layout.getColumns());
+        List<Integer> possibleYCandidates = list(layout.getRows());
+
+        uni.y = last(possibleYCandidates, 1);
+
+        if (layout.getRows()
+                .filter(y -> layout.getRow(y).size() == 1).count() < 2) {
+            uni.y += 25;
+            uni.x = first(possibleXCandidates, 0);
+
+            layout.getRow(last(possibleYCandidates, 0)).forEach(button -> {
+                button.y = Math.max(button.y, uni.y + uni.height + 13);
+            });
+        } else {
+            uni.x = first(possibleXCandidates, 2);
+        }
+
+        layout.getElements().add(uni);
+    }
+
     @SideOnly(Side.CLIENT)
     @SubscribeEvent
     public static void preEntityRender(RenderLivingEvent.Pre<?> event) {

src/main/java/com/minelittlepony/util/gui/ButtonGridLayout.java

@@ -0,0 +1,90 @@
+package com.minelittlepony.util.gui;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import net.minecraft.client.gui.GuiButton;
+
+public class ButtonGridLayout {
+
+    private List<GuiButton> elements;
+
+    private Map<Integer, List<GuiButton>> leftLookup = new HashMap<>();
+    private Map<Integer, List<GuiButton>> topLookup = new HashMap<>();
+
+    private Map<Integer, List<GuiButton>> idLookup = new HashMap<>();
+
+    private int nextButtonId = -1;
+
+    public ButtonGridLayout(List<GuiButton> elements) {
+        elements.forEach(this::addElement);
+        this.elements = elements;
+    }
+
+    public int getNextButtonId() {
+        return nextButtonId++;
+    }
+
+    public GuiButton addElement(GuiButton button) {
+        if (elements != null) {
+            elements.add(button);
+        }
+        getColumn(button.x).add(button);
+        getRow(button.y).add(button);
+        getButton(button.id).add(button);
+
+        while (button.id >= nextButtonId) {
+            getNextButtonId();
+        }
+
+        return button;
+    }
+
+    public List<GuiButton> getElements() {
+        return elements;
+    }
+
+    public List<GuiButton> getRow(int y) {
+        return topLookup.computeIfAbsent(y, ArrayList::new);
+    }
+
+    public List<GuiButton> getColumn(int x) {
+        return leftLookup.computeIfAbsent(x, ArrayList::new);
+    }
+
+    public List<GuiButton> getButton(int id) {
+        return idLookup.computeIfAbsent(id, ArrayList::new);
+    }
+
+    public Stream<Integer> getButtonIds() {
+        return idLookup.keySet().stream().sorted();
+    }
+
+    public Stream<Integer> getColumns() {
+        return leftLookup.keySet().stream().sorted();
+    }
+
+    public Stream<Integer> getRows() {
+        return topLookup.keySet().stream().sorted();
+    }
+
+    public Stream<Integer> getIds() {
+        return idLookup.keySet().stream().sorted();
+    }
+
+    public static <T> List<T> list(Stream<T> s) {
+        return s.collect(Collectors.toList());
+    }
+
+    public static <T> T first(List<T> c, int i) {
+        return c.get(i);
+    }
+
+    public static <T> T last(List<T> c, int i) {
+        return first(c, (c.size() - 1) - i);
+    }
+}

src/main/java/com/minelittlepony/util/gui/UButton.java

@@ -0,0 +1,24 @@
+package com.minelittlepony.util.gui;
+
+import java.util.function.Function;
+
+import net.minecraft.client.Minecraft;
+import net.minecraft.client.gui.GuiButton;
+
+public class UButton extends GuiButton {
+
+    private final Function<GuiButton, Boolean> action;
+
+    public UButton(int id, int x, int y, int w, int h, String label, Function<GuiButton, Boolean> action) {
+        super(id, x, y, w, h, label);
+        this.action = action;
+    }
+
+    public boolean mousePressed(Minecraft mc, int mouseX, int mouseY) {
+        if (super.mousePressed(mc, mouseX, mouseY)) {
+            return action.apply(this);
+        }
+
+        return false;
+    }
+}

src/main/resources/assets/unicopia/lang/en_US.lang

@@ -101,6 +101,8 @@ toxicity.fair.name=Fairly Toxic
 toxicity.severe.name=Toxic
 toxicity.lethal.name=Lethal
 
+gui.unicopia=Unicopia...
+
 commands.race.success.self=Your race has been updated
 commands.race.success.otherself=%s changed race to %s
 commands.race.success.other=Changed %s's race to %s