equivalent-exchange-3/src/main/java/com/pahimar/ee3/handler/DrawBlockHighlightHandler.java

package com.pahimar.ee3.handler;

import com.pahimar.ee3.configuration.ConfigurationSettings;
import com.pahimar.ee3.helper.TransmutationHelper;
import com.pahimar.ee3.item.IChargeable;
import com.pahimar.ee3.item.ITransmutationStone;
import com.pahimar.ee3.lib.Textures;
import cpw.mods.fml.client.FMLClientHandler;
import cpw.mods.fml.relauncher.Side;
import cpw.mods.fml.relauncher.SideOnly;
import net.minecraft.client.Minecraft;
import net.minecraft.client.renderer.Tessellator;
import net.minecraft.util.EnumMovingObjectType;
import net.minecraft.util.ResourceLocation;
import net.minecraftforge.client.event.DrawBlockHighlightEvent;
import net.minecraftforge.common.ForgeDirection;
import net.minecraftforge.event.ForgeSubscribe;
import org.lwjgl.opengl.GL11;
import org.lwjgl.opengl.GL12;

/**
 * Equivalent-Exchange-3
 * <p/>
 * DrawBlockHighlightHandler
 *
 * @author pahimar
 */
@SideOnly(Side.CLIENT)
public class DrawBlockHighlightHandler
{

    private static int pulse = 0;
    private static boolean doInc = true;

    @ForgeSubscribe
    public void onDrawBlockHighlightEvent(DrawBlockHighlightEvent event)
    {

        Minecraft minecraft = FMLClientHandler.instance().getClient();

        if (event.currentItem != null)
        {
            if (event.currentItem.getItem() instanceof ITransmutationStone)
            {
                if (event.target.typeOfHit == EnumMovingObjectType.TILE)
                {
                    TransmutationHelper.updateTargetBlock(event.player.worldObj, event.target.blockX, event.target.blockY, event.target.blockZ);

                    if (Minecraft.isGuiEnabled() && minecraft.inGameHasFocus)
                    {
                        if (ConfigurationSettings.ENABLE_OVERLAY_WORLD_TRANSMUTATION)
                        {
                            drawInWorldTransmutationOverlay(event);
                        }
                    }
                }
            }
        }
    }

    public void drawInWorldTransmutationOverlay(DrawBlockHighlightEvent event)
    {

        double x = event.target.blockX + 0.5F;
        double y = event.target.blockY + 0.5F;
        double z = event.target.blockZ + 0.5F;
        double iPX = event.player.prevPosX + (event.player.posX - event.player.prevPosX) * event.partialTicks;
        double iPY = event.player.prevPosY + (event.player.posY - event.player.prevPosY) * event.partialTicks;
        double iPZ = event.player.prevPosZ + (event.player.posZ - event.player.prevPosZ) * event.partialTicks;

        float xScale = 1;
        float yScale = 1;
        float zScale = 1;
        float xShift = 0.1F;
        float yShift = 0.1F;
        float zShift = 0.1F;
        int chargeLevel;
        int itemChargeLevel = 0;

        if (event.currentItem.getItem() instanceof IChargeable)
        {
            itemChargeLevel = ((IChargeable) event.currentItem.getItem()).getCharge(event.currentItem);
        }
        chargeLevel = 1 + itemChargeLevel * 2;

        ForgeDirection sideHit = ForgeDirection.getOrientation(event.target.sideHit);

        switch (sideHit)
        {
            case UP:
            {
                xScale = chargeLevel + 0.1F;
                zScale = chargeLevel + 0.1F;
                xShift = 0;
                zShift = 0;
                break;
            }
            case DOWN:
            {
                xScale = chargeLevel + 0.1F;
                zScale = chargeLevel + 0.1F;
                xShift = 0;
                yShift = -yShift;
                zShift = 0;
                break;
            }
            case NORTH:
            {
                xScale = chargeLevel + 0.1F;
                yScale = chargeLevel + 0.1F;
                xShift = 0;
                yShift = 0;
                zShift = -zShift;
                break;
            }
            case SOUTH:
            {
                xScale = chargeLevel + 0.1F;
                yScale = chargeLevel + 0.1F;
                xShift = 0;
                yShift = 0;
                break;
            }
            case EAST:
            {
                yScale = chargeLevel + 0.1F;
                zScale = chargeLevel + 0.1F;
                yShift = 0;
                zShift = 0;
                break;
            }
            case WEST:
            {
                yScale = chargeLevel + 0.1F;
                zScale = chargeLevel + 0.1F;
                xShift = -xShift;
                yShift = 0;
                zShift = 0;
                break;
            }
            default:
                break;
        }

        GL11.glDepthMask(false);
        GL11.glDisable(GL11.GL_CULL_FACE);

        for (int i = 0; i < 6; i++)
        {
            ForgeDirection forgeDir = ForgeDirection.getOrientation(i);
            int zCorrection = i == 2 ? -1 : 1;
            GL11.glPushMatrix();
            GL11.glTranslated(-iPX + x + xShift, -iPY + y + yShift, -iPZ + z + zShift);
            GL11.glScalef(1F * xScale, 1F * yScale, 1F * zScale);
            GL11.glRotatef(90, forgeDir.offsetX, forgeDir.offsetY, forgeDir.offsetZ);
            GL11.glTranslated(0, 0, 0.5f * zCorrection);
            GL11.glClear(GL11.GL_DEPTH_BUFFER_BIT);
            renderPulsingQuad(Textures.EFFECT_WORLD_TRANSMUTATION, 0.75F);
            GL11.glPopMatrix();
        }

        GL11.glEnable(GL11.GL_CULL_FACE);
        GL11.glDepthMask(true);
    }

    public static void renderPulsingQuad(ResourceLocation texture, float maxTransparency)
    {

        float pulseTransparency = getPulseValue() * maxTransparency / 3000f;

        FMLClientHandler.instance().getClient().renderEngine.bindTexture(texture);
        Tessellator tessellator = Tessellator.instance;

        GL11.glEnable(GL12.GL_RESCALE_NORMAL);
        GL11.glEnable(GL11.GL_BLEND);
        GL11.glBlendFunc(GL11.GL_SRC_ALPHA, GL11.GL_ONE_MINUS_SRC_ALPHA);
        GL11.glColor4f(1, 1, 1, pulseTransparency);

        tessellator.startDrawingQuads();
        tessellator.setColorRGBA_F(1, 1, 1, pulseTransparency);

        tessellator.addVertexWithUV(-0.5D, 0.5D, 0F, 0, 1);
        tessellator.addVertexWithUV(0.5D, 0.5D, 0F, 1, 1);
        tessellator.addVertexWithUV(0.5D, -0.5D, 0F, 1, 0);
        tessellator.addVertexWithUV(-0.5D, -0.5D, 0F, 0, 0);

        tessellator.draw();
        GL11.glDisable(GL11.GL_BLEND);
        GL11.glDisable(GL12.GL_RESCALE_NORMAL);
    }

    private static int getPulseValue()
    {

        if (doInc)
        {
            pulse += 8;
        }
        else
        {
            pulse -= 8;
        }

        if (pulse == 3000)
        {
            doInc = false;
        }

        if (pulse == 0)
        {
            doInc = true;
        }

        return pulse;
    }
}