Fix goof with segment number

WhistleGui.java

package com.leviathan143.dogwhistle.client.handlers;

import java.util.List;
import java.util.Map;

import org.lwjgl.input.Mouse;
import org.lwjgl.opengl.GL11;

import com.google.common.collect.Maps;
import com.leviathan143.dogwhistle.api.whistle.Whistle;
import com.leviathan143.dogwhistle.api.whistle.WhistleRegistry;
import com.leviathan143.dogwhistle.api.whistle.WhistleRegistry.WhistleType;
import com.leviathan143.dogwhistle.client.GuiParameters;
import com.leviathan143.dogwhistle.common.packets.PacketHandler;
import com.leviathan143.dogwhistle.common.packets.PacketWhistleAction;

import net.minecraft.client.Minecraft;
import net.minecraft.client.gui.ScaledResolution;
import net.minecraft.client.renderer.GlStateManager;
import net.minecraft.client.renderer.Tessellator;
import net.minecraft.client.renderer.VertexBuffer;
import net.minecraft.client.renderer.vertex.DefaultVertexFormats;
import net.minecraftforge.client.event.MouseEvent;
import net.minecraftforge.client.event.RenderGameOverlayEvent;
import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;

public class WhistleGui
{
	private static final double SEGMENT_OFFSET = 2.5;
	private static final Map<Integer, GuiParameters> parameterMap = Maps.newHashMap();

	static
	{
		parameterMap.put(1, new GuiParameters(24, 15));
		parameterMap.put(2, new GuiParameters(12, 15));
		parameterMap.put(3, new GuiParameters(8, 15));
		parameterMap.put(4, new GuiParameters(6, 15));
		parameterMap.put(5, new GuiParameters(4, 18));
		parameterMap.put(6, new GuiParameters(4, 15));
		parameterMap.put(7, new GuiParameters(3, 17.1428F));
		parameterMap.put(8, new GuiParameters(3, 15));
		parameterMap.put(9, new GuiParameters(2, 20));
		parameterMap.put(10, new GuiParameters(2, 18));
	}

	private static Minecraft mc = Minecraft.getMinecraft();
	private static WhistleType whistleType;
	private static Object additionalParam;
	private static boolean isActive;

	private static int segments, subsegments, hoveredSegment = -1;
	private static float radius = 50.0F, segmentAngle;

	@SubscribeEvent
	public static void onRenderGameOverlay(RenderGameOverlayEvent.Pre event)
	{
		if(!isActive || whistleType == WhistleType.NONE) return;
		if(event.getType() == RenderGameOverlayEvent.ElementType.CROSSHAIRS)
		{
			renderWhistleGui(whistleType, event.getResolution().getScaledWidth() / 2, event.getResolution().getScaledHeight() / 2);
			event.setCanceled(true);
		}
	}

	private static void renderWhistleGui(WhistleType type, int x, int y)
	{
		List<Whistle> whistles = WhistleRegistry.getWhistlesByType(type);
		segments = whistles.size();
		if(!parameterMap.containsKey(segments)) return;
		subsegments = parameterMap.get(segments).getSubsegments();
		float subsegmentAngle = parameterMap.get(segments).getAngle();
		segmentAngle = subsegmentAngle * subsegments;

		Tessellator tess = Tessellator.getInstance();
		VertexBuffer vtxBuf = tess.getBuffer();
		GlStateManager.pushMatrix();

		GlStateManager.translate(x, y, 0.0F);
		//Dark mathgic to rotate segment 0 to 0 degrees
		GlStateManager.rotate((segments / -2.0F + 1.0F) * segmentAngle, 0, 0, 1);
		for(int segment = 0; segment < segments; segment++)
		{
			GlStateManager.pushMatrix();
			GlStateManager.translate(SEGMENT_OFFSET * Math.cos(Math.toRadians(90 - segmentAngle / 2)), SEGMENT_OFFSET * Math.cos(Math.toRadians(segmentAngle / 2)), 0);
			for(int subsegment = 0; subsegment < subsegments; subsegment++)
			{
				vtxBuf.begin(segment == hoveredSegment ? GL11.GL_TRIANGLE_FAN : GL11.GL_LINE_LOOP, DefaultVertexFormats.POSITION);
				vtxBuf.pos(0, 0 , 0).endVertex();
				vtxBuf.pos(0, radius, 0).endVertex();
				vtxBuf.pos(radius * Math.cos(Math.toRadians(90 - subsegmentAngle)), radius * Math.cos(Math.toRadians(subsegmentAngle)), 0).endVertex();
				tess.draw();
				GlStateManager.rotate(-subsegmentAngle, 0, 0, 1);
			}
			GlStateManager.popMatrix();
			GlStateManager.rotate(segmentAngle, 0, 0, 1);
		}
		for(int segment = 0; segment < segments; segment++)
		{
			renderWhistleIcon(whistles.get(segment),(float) ((radius / 2.0F) * Math.cos(Math.toRadians(90 - segmentAngle / 2))), (float) ((radius / 2.0F) * Math.cos(Math.toRadians(segmentAngle / 2))), segment);
			GlStateManager.rotate(segmentAngle, 0.0F, 0.0F, 1.0F);
		}
		GlStateManager.popMatrix();
	}

	private static void renderWhistleIcon(Whistle whistle, float x, float y, int segment) 
	{
		GlStateManager.pushMatrix();
		GlStateManager.enableAlpha();
		GlStateManager.translate(x, y, 0);
		//Reverse the dark mathgic
		GlStateManager.rotate(-segmentAngle * segment + (segments / 2.0F - 1.0F) * segmentAngle, 0, 0, 1);
		Tessellator tess = Tessellator.getInstance();
		VertexBuffer vtxBuf = tess.getBuffer();

		mc.getTextureManager().bindTexture(whistle.getResource());
		vtxBuf.begin(GL11.GL_QUADS, DefaultVertexFormats.POSITION_TEX);
		vtxBuf.pos(-8, -8, 1).tex(0.0D, 0.0D).endVertex();
		vtxBuf.pos(-8, 8, 1).tex(0.0D, 1.0D).endVertex();
		vtxBuf.pos(8, 8, 1).tex(1.0D, 1.0D).endVertex();
		vtxBuf.pos(8, -8, 1).tex(1.0D, 0.0D).endVertex();
		tess.draw();
		GlStateManager.disableAlpha();
		GlStateManager.popMatrix();
	}

	@SubscribeEvent
	public static void handleMouseInput(MouseEvent event)
	{
		if(!isActive) return;
		int mouseX = transformMouseX() - mc.displayWidth / 4;
		int mouseY = transformMouseY() - mc.displayHeight / 4;
		handleMovement(event, mouseX, mouseY);
		if(event.getButton() != -1) handleClicks(event, mouseX, mouseY);
	}

	public static void handleMovement(MouseEvent event, int mouseX, int mouseY)
	{
		if((mouseX <= radius && mouseX >= -radius ) && (mouseY <= radius && mouseY >= -radius ))
		{
			double mouseAngle = calcMouseAngle(mouseX, mouseY);
			for(int segment = 0; segment < segments; segment++)
			{
				//All hail inverse modulus!
				hoveredSegment = (int) ((mouseAngle - mouseAngle % segmentAngle) / segmentAngle);
			}
		}
		else
		{
			hoveredSegment = -1;
		}
	}

	public static void handleClicks(MouseEvent event, int mouseX, int mouseY)
	{
		if(hoveredSegment == -1)
		{
			toggleState();
		}
		else if(event.getButton() == 0 && event.isButtonstate())
		{
			System.out.println(whistleType);
			PacketHandler.CHANNEL.sendToServer(new PacketWhistleAction(mc.theWorld, mc.thePlayer, additionalParam, WhistleRegistry.getWhistlesByType(whistleType).get(hoveredSegment)));
			toggleState();
		}
	}


	private static double calcMouseAngle(double mouseX, double mouseY)
	{
		//The + 90.0D moves 0 degrees to the top of the gui
		return wrapD(Math.toDegrees(Math.atan2(mouseY, mouseX)) + 90.0D, 0.0D, 360.0D);
	}

	/*private static float wrapF(float in, float min, float max)
	{
		if(in < min)
			in = max + in - min;
		if(in > max)
			in = in - max + min;
		return in;
	}*/
	
	private static double wrapD(double in, double min, double max)
	{
		if(in < min)
			in = max + in - min;
		if(in > max)
			in = in - max + min;
		return in;
	}

	/*private static double wrapI(double in, double min, double max)
	{
		if(in < min)
			in = max + in - min;
		if(in > max)
			in = in - max + min;
		return in;
	}*/

	private static int transformMouseX()
	{
		ScaledResolution scaledresolution = new ScaledResolution(mc);
		int scaledWidth = scaledresolution.getScaledWidth();
		return Mouse.getX() * scaledWidth / mc.displayWidth;
	}

	private static int transformMouseY()
	{
		ScaledResolution scaledresolution = new ScaledResolution(mc);
		int scaledHeight = scaledresolution.getScaledHeight();
		return scaledHeight - Mouse.getY() * scaledHeight / mc.displayHeight - 1;
	}

	public static boolean toggleState() 
	{
		isActive = !isActive;
		if (isActive) mc.setIngameNotInFocus(); 
		else mc.setIngameFocus();
		hoveredSegment = -1;
		return isActive;
	}
	
	public static void initialise(WhistleType  type, Object addParam)
	{
		whistleType = type;
		additionalParam = addParam;
	}
}