unreal/AdventureMap.cpp

// Fill out your copyright notice in the Description page of Project Settings.


#include "AdventureMap.h"
#include "HexTile.h"
#include "AdventureCameraPawn.h"
#include "AdventureCharacter.h"
#include "Kismet/GameplayStatics.h"


// Sets default values
AAdventureMap::AAdventureMap()
{
}

// Called when the game starts or when spawned
void AAdventureMap::BeginPlay()
{
	Super::BeginPlay();
	UWorld* World = GetWorld();
	if (IsValid(BaseTileClass)) 
	{ 
		MakeGrid();
	}
}

// Called once on Begin Play
void AAdventureMap::MakeGrid() 
{	
	UWorld* World = GetWorld();
	FVector NextHexAt = FVector();
	float HexWidth = sqrt(3) * TileSize;
	int QOffset = 0;

	for (int r = 1; r <= GridSize; r++) 
	{
		float XOffset = 0.f;

		if (r % 2 != 0)	
		{ 
			if (r > 1) 
			{
				QOffset--; // The Q axis is (i.e. columns are) oriented diagonally.
			}	
		}
		else
		{
			XOffset = HexWidth / 2;
		}

		for (int q = 1; q <= GridSize; q++)
		{
			NextHexAt.X = XOffset + (HexWidth * q);
			NextHexAt.Y = TileSize * 1.5f * r;
			NextHexAt.Z = 0.f;

			FTransform SpawnTransform = FTransform(NextHexAt);
			AHexTile* Tile = World->SpawnActor<AHexTile>(BaseTileClass, SpawnTransform);

			Tile->Q = q - 1 + QOffset;
			Tile->R = r - 1;

			Grid.Add(Tile);
		}
	}

	for (auto& tile : Grid)
	{
		tile->Index = GridIndex(tile->Q, tile->R);
	}

	bHexGridReady = true;
}

// Every Hex Tile's index within the Grid Array can be derived from its Q and R coordinates
int32 AAdventureMap::GridIndex(int32 qAxial, int32 rAxial)
{
	/*
	*	The Q axis is (i.e. columns are) oriented diagonally.
	*	The Hex Grid has a rough square shape, hence the Q coordinates must be offset by -1 every other row.
	*/
	int32 column = qAxial + FMath::FloorToInt(rAxial / 2);
	return (rAxial * GridSize) + column;
}

AHexTile* AAdventureMap::RandomHex()
{
	int32 RandHex = GridIndex(FMath::RandRange(0, GridSize), FMath::RandRange(0, GridSize));
	while (RandHex > Grid.Num())
	{
		RandHex = GridIndex(FMath::RandRange(0, GridSize), FMath::RandRange(0, GridSize));
	}
	return Grid[RandHex];
}

TArray<AHexTile*> AAdventureMap::Neighbors(AHexTile* OfHex)
{
	TArray<AHexTile*> Neighbors;
	int32 Index;

	Index = GridIndex(OfHex->Q + 1	, OfHex->R + 0	);
	if (Index < Grid.Num() && Index >= 0) { Neighbors.Add(Grid[Index]); }

	Index = GridIndex(OfHex->Q + 1	, OfHex->R - 1	);
	if (Index < Grid.Num() && Index >= 0) { Neighbors.Add(Grid[Index]); }

	Index = GridIndex(OfHex->Q + 0	, OfHex->R - 1	);
	if (Index < Grid.Num() && Index >= 0) { Neighbors.Add(Grid[Index]); }

	Index = GridIndex(OfHex->Q - 1	, OfHex->R + 0	);
	if (Index < Grid.Num() && Index >= 0) { Neighbors.Add(Grid[Index]); }

	Index = GridIndex(OfHex->Q - 1	, OfHex->R + 1	);
	if (Index < Grid.Num() && Index >= 0) { Neighbors.Add(Grid[Index]); }

	Index = GridIndex(OfHex->Q + 0	, OfHex->R + 1	);
	if (Index < Grid.Num() && Index >= 0) { Neighbors.Add(Grid[Index]); }

	return Neighbors; // currently wrapping from corner to corner --> rectify this with a manhattan distance check
}