VoxelEngine/src/voxels/Chunks.cpp

#include "Chunks.h"
#include "Chunk.h"
#include "voxel.h"
#include "Block.h"
#include "WorldGenerator.h"
#include "../content/Content.h"
#include "../lighting/Lightmap.h"
#include "../files/WorldFiles.h"
#include "../world/LevelEvents.h"

#include "../graphics/Mesh.h"
#include "../maths/voxmaths.h"
#include "../maths/aabb.h"
#include "../maths/rays.h"

#include <math.h>
#include <limits.h>

using glm::vec3;
using glm::ivec3;
using std::shared_ptr;

Chunks::Chunks(int w, int d, 
			   int ox, int oz, 
			   WorldFiles* wfile, 
			   LevelEvents* events, 
			   const Content* content) 
		: content(content),
		  contentIds(content->indices), 
		  w(w), d(d), ox(ox), oz(oz), 
		  worldFiles(wfile), 
		  events(events) {
	volume = (size_t)w*(size_t)d;
	chunks = new shared_ptr<Chunk>[volume];
	chunksSecond = new shared_ptr<Chunk>[volume];

	for (size_t i = 0; i < volume; i++){
		chunks[i] = nullptr;
	}
	chunksCount = 0;
}

Chunks::~Chunks(){
	for (size_t i = 0; i < volume; i++){
		chunks[i] = nullptr;
	}
	delete[] chunks;
}

voxel* Chunks::get(int x, int y, int z){
	x -= ox * CHUNK_W; 
	z -= oz * CHUNK_D;
	int cx = x / CHUNK_W;
	int cy = y / CHUNK_H;
	int cz = z / CHUNK_D;
	if (x < 0) cx--;
	if (y < 0) cy--;
	if (z < 0) cz--;
	if (cx < 0 || cy < 0 || cz < 0 || cx >= w || cy >= 1 || cz >= d)
		return nullptr;
	shared_ptr<Chunk> chunk = chunks[cz * w + cx]; // chunks is 2D-array
	if (chunk == nullptr)
		return nullptr;
	int lx = x - cx * CHUNK_W;
	int ly = y - cy * CHUNK_H;
	int lz = z - cz * CHUNK_D;
	return &chunk->voxels[(ly * CHUNK_D + lz) * CHUNK_W + lx];
}

const AABB* Chunks::isObstacle(float x, float y, float z){
	int ix = floor(x);
	int iy = floor(y);
	int iz = floor(z);
	voxel* v = get(ix,iy,iz);
	if (v == nullptr)
		return nullptr;
	const Block* def = contentIds->getBlockDef(v->id);
	if (def->obstacle) {
		const AABB& hitbox = def->rotatable 
							 ? def->rt.hitboxes[v->rotation()] 
							 : def->hitbox;
		if (def->rt.solid) {
			return &hitbox;
		} else {
			if (hitbox.inside({x - ix, y - iy, z - iz}))
				return &hitbox;
			return nullptr;
		}
	}
	return nullptr;
}

ubyte Chunks::getLight(int x, int y, int z, int channel){
	x -= ox * CHUNK_W;
	z -= oz * CHUNK_D;
	int cx = floordiv(x, CHUNK_W);
	int cy = floordiv(y, CHUNK_H);
	int cz = floordiv(z, CHUNK_D);
	if (cx < 0 || cy < 0 || cz < 0 || cx >= w || cy >= 1 || cz >= d)
		return 0;
	shared_ptr<Chunk> chunk = chunks[(cy * d + cz) * w + cx];
	if (chunk == nullptr)
		return 0;
	int lx = x - cx * CHUNK_W;
	int ly = y - cy * CHUNK_H;
	int lz = z - cz * CHUNK_D;
	return chunk->lightmap->get(lx,ly,lz, channel);
}

light_t Chunks::getLight(int x, int y, int z){
	x -= ox * CHUNK_W;
	z -= oz * CHUNK_D;
	int cx = floordiv(x, CHUNK_W);
	int cy = floordiv(y, CHUNK_H);
	int cz = floordiv(z, CHUNK_D);
	if (cx < 0 || cy < 0 || cz < 0 || cx >= w || cy >= 1 || cz >= d)
		return 0;
	shared_ptr<Chunk> chunk = chunks[(cy * d + cz) * w + cx];
	if (chunk == nullptr)
		return 0;
	int lx = x - cx * CHUNK_W;
	int ly = y - cy * CHUNK_H;
	int lz = z - cz * CHUNK_D;
	return chunk->lightmap->get(lx,ly,lz);
}

Chunk* Chunks::getChunkByVoxel(int x, int y, int z){
	if (y < 0 || y >= CHUNK_H)
		return nullptr;
	x -= ox * CHUNK_W;
	z -= oz * CHUNK_D;
	int cx = floordiv(x, CHUNK_W);
	int cz = floordiv(z, CHUNK_D);
	if (cx < 0 || cz < 0 || cx >= w || cz >= d)
		return nullptr;
	return chunks[cz * w + cx].get();
}

Chunk* Chunks::getChunk(int x, int z){
	x -= ox;
	z -= oz;
	if (x < 0 || z < 0 || x >= w || z >= d)
		return nullptr;
	return chunks[z * w + x].get();
}

void Chunks::set(int x, int y, int z, int id, uint8_t states){
	if (y < 0 || y >= CHUNK_H)
		return;
	x -= ox * CHUNK_W;
	z -= oz * CHUNK_D;
	int cx = floordiv(x, CHUNK_W);
	int cz = floordiv(z, CHUNK_D);
	if (cx < 0 || cz < 0 || cx >= w || cz >= d)
		return;
	Chunk* chunk = chunks[cz * w + cx].get();
	if (chunk == nullptr)
		return;
	int lx = x - cx * CHUNK_W;
	int lz = z - cz * CHUNK_D;
	chunk->voxels[(y * CHUNK_D + lz) * CHUNK_W + lx].id = id;
	chunk->voxels[(y * CHUNK_D + lz) * CHUNK_W + lx].states = states;
	chunk->setUnsaved(true);
	chunk->setModified(true);

	if (y < chunk->bottom) chunk->bottom = y;
	else if (y + 1 > chunk->top) chunk->top = y + 1;
	else if (id == 0) chunk->updateHeights();

	if (lx == 0 && (chunk = getChunk(cx+ox-1, cz+oz))) 
		chunk->setModified(true);
	if (lz == 0 && (chunk = getChunk(cx+ox, cz+oz-1))) 
		chunk->setModified(true);

	if (lx == CHUNK_W-1 && (chunk = getChunk(cx+ox+1, cz+oz))) 
		chunk->setModified(true);
	if (lz == CHUNK_D-1 && (chunk = getChunk(cx+ox, cz+oz+1))) 
		chunk->setModified(true);
}
#include "../util/timeutil.h"
voxel* Chunks::rayCast(vec3 start, 
					   vec3 dir, 
					   float maxDist, 
					   vec3& end, 
					   ivec3& norm, 
					   ivec3& iend) {
	float px = start.x;
	float py = start.y;
	float pz = start.z;

	float dx = dir.x;
	float dy = dir.y;
	float dz = dir.z;

	float t = 0.0f;
	int ix = floor(px);
	int iy = floor(py);
	int iz = floor(pz);

	int stepx = (dx > 0.0f) ? 1 : -1;
	int stepy = (dy > 0.0f) ? 1 : -1;
	int stepz = (dz > 0.0f) ? 1 : -1;

	constexpr float infinity = std::numeric_limits<float>::infinity();

	float txDelta = (dx == 0.0f) ? infinity : abs(1.0f / dx);
	float tyDelta = (dy == 0.0f) ? infinity : abs(1.0f / dy);
	float tzDelta = (dz == 0.0f) ? infinity : abs(1.0f / dz);

	float xdist = (stepx > 0) ? (ix + 1 - px) : (px - ix);
	float ydist = (stepy > 0) ? (iy + 1 - py) : (py - iy);
	float zdist = (stepz > 0) ? (iz + 1 - pz) : (pz - iz);

	float txMax = (txDelta < infinity) ? txDelta * xdist : infinity;
	float tyMax = (tyDelta < infinity) ? tyDelta * ydist : infinity;
	float tzMax = (tzDelta < infinity) ? tzDelta * zdist : infinity;

	int steppedIndex = -1;      
                                
	while (t <= maxDist){       
		voxel* voxel = get(ix, iy, iz);		
		if (!voxel){ return nullptr; }

		const Block* def = contentIds->getBlockDef(voxel->id);
		if (def->selectable){
			timeutil::ScopeLogTimer lg((long long)def);
			end.x = px + t * dx;
			end.y = py + t * dy;
			end.z = pz + t * dz;
					iend.x = ix;
					iend.y = iy;
					iend.z = iz;
			
			if (!def->rt.solid) {
				const AABB& box = def->rotatable 
								  ? def->rt.hitboxes[voxel->rotation()] 
								  : def->hitbox;
				rayvec3 in, out; // <- now not used, but for future...
				if (Rays::rayIntersectAABB(start, dir, iend, box, maxDist, in, out, norm) > RayRelation::None){
					return voxel;
				}

			} else {
				iend.x = ix;
				iend.y = iy;
				iend.z = iz;

				norm.x = norm.y = norm.z = 0;
				if (steppedIndex == 0) norm.x = -stepx;
				if (steppedIndex == 1) norm.y = -stepy;
				if (steppedIndex == 2) norm.z = -stepz;
				return voxel;
			}
		}
		if (txMax < tyMax) {
			if (txMax < tzMax) {
				ix += stepx;
				t = txMax;
				txMax += txDelta;
				steppedIndex = 0;
			} else {
				iz += stepz;
				t = tzMax;
				tzMax += tzDelta;
				steppedIndex = 2;
			}
		} else {
			if (tyMax < tzMax) {
				iy += stepy;
				t = tyMax;
				tyMax += tyDelta;
				steppedIndex = 1;
			} else {
				iz += stepz;
				t = tzMax;
				tzMax += tzDelta;
				steppedIndex = 2;
			}
		}
	}
	iend.x = ix;
	iend.y = iy;
	iend.z = iz;

	end.x = px + t * dx;
	end.y = py + t * dy;
	end.z = pz + t * dz;
	norm.x = norm.y = norm.z = 0;
	return nullptr;
}

void Chunks::setCenter(int x, int z) {
	int cx = floordiv(x, CHUNK_W);
	int cz = floordiv(z, CHUNK_D);
	cx -= ox + w / 2;
	cz -= oz + d / 2;
	if (cx | cz) {
		translate(cx,cz);
	}
}

void Chunks::translate(int dx, int dz){
	for (uint i = 0; i < volume; i++){
		chunksSecond[i] = nullptr;
	}
	for (int z = 0; z < d; z++){
		for (int x = 0; x < w; x++){
			shared_ptr<Chunk> chunk = chunks[z * w + x];
			int nx = x - dx;
			int nz = z - dz;
			if (chunk == nullptr)
				continue;
			if (nx < 0 || nz < 0 || nx >= w || nz >= d){
				events->trigger(EVT_CHUNK_HIDDEN, chunk.get());
				if (worldFiles)
					worldFiles->put(chunk.get());
				chunksCount--;
				continue;
			}
			chunksSecond[nz * w + nx] = chunk;
		}
	}
	std::swap(chunks, chunksSecond);

	ox += dx;
	oz += dz;
}

void Chunks::resize(int newW, int newD) {
	if (newW < w) {
		int delta = w - newW;
		translate(delta / 2, 0);
		translate(-delta, 0);
		translate(delta, 0);
	}
	if (newD < d) {
		int delta = d - newD;
		translate(0, delta / 2);
		translate(0, -delta);
		translate(0, delta);
	}
	const int newVolume = newW * newD;
	auto newChunks = new shared_ptr<Chunk>[newVolume] {};
	auto newChunksSecond = new shared_ptr<Chunk>[newVolume] {};
	for (int z = 0; z < d && z < newD; z++) {
		for (int x = 0; x < w && x < newW; x++) {
			newChunks[z * newW + x] = chunks[z * w + x];
		}
	}
	delete[] chunks;
	delete[] chunksSecond;
	w = newW;
	d = newD;
	volume = newVolume;
	chunks = newChunks;
	chunksSecond = newChunksSecond;
}

void Chunks::_setOffset(int x, int z){
	ox = x;
	oz = z;
}

bool Chunks::putChunk(shared_ptr<Chunk> chunk) {
	int x = chunk->x;
	int z = chunk->z;
	x -= ox;
	z -= oz;
	if (x < 0 || z < 0 || x >= w || z >= d)
		return false;
	chunks[z * w + x] = chunk;
	chunksCount++;
	return true;
}

void Chunks::saveAndClear(){
	for (size_t i = 0; i < volume; i++){
		Chunk* chunk = chunks[i].get();
		if (chunk) {
			worldFiles->put(chunk);
			events->trigger(EVT_CHUNK_HIDDEN, chunk);
		}
		chunks[i] = nullptr;
	}
	chunksCount = 0;
}