RayTraceResult res = /*world.isRemote? Minecraft.getMinecraft().objectMouseOver :*/RayTracer.retrace(player,16);
BlockPos to = res.getBlockPos();
if(player.getDistanceSqToCenter(to)>16*16)return;
if(world.isRemote){
//FIXME to is the player position (client side) if using world.raytrace
world.spawnParticle(EnumParticleTypes.SPELL, true, to.getX()+0.5, to.getY(), to.getZ()+0.5, 0d, 0d, 0d, 0);
}else{
((WorldServer)world).spawnParticle(EnumParticleTypes.SPELL_MOB, to.getX()+0.5, to.getY(), to.getZ()+0.5, 10, 0d, 0d, 0d, 0);
                    }
public static RayTraceResult retrace(EntityPlayer player, double reach) {
        Vec3d headVec = getCorrectedHeadVec(player);
        Vec3d lookVec = player.getLook(1);
        Vec3d endVec = headVec.addVector(lookVec.xCoord * reach, lookVec.yCoord * reach, lookVec.zCoord * reach);
        return player.worldObj.rayTraceBlocks(headVec, endVec, true, false, true);
    }

public static Vec3d getCorrectedHeadVec(EntityPlayer player) {
        double y = player.posY;
        if (player.worldObj.isRemote) {
            //compatibility with eye height changing mods
            y += player.getEyeHeight() - player.getDefaultEyeHeight();
        } else {
            y += player.getEyeHeight();
            if (player instanceof EntityPlayerMP && player.isSneaking())
                y -= 0.08;
        }
        return new Vec3d(player.posX,y,player.posZ);
}