ppsspp/GPU/Common/ReplacedTexture.h

// Copyright (c) 2016- PPSSPP Project.

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, version 2.0 or later versions.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License 2.0 for more details.

// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/

// Official git repository and contact information can be found at
// https://github.com/hrydgard/ppsspp and http://www.ppsspp.org/.

#pragma once

#include <retro_atomic.h>
#include <string>

#include "Common/File/VFS/VFS.h"
#include "Common/GPU/thin3d.h"
#include "Core/ConfigValues.h"
#include "GPU/Common/ImageCommon.h"

class TextureReplacer;
class LimitedWaitable;

// For forward compatibility, we specify the hash.
enum class ReplacedTextureHash {
	QUICK,
	XXH32,
	XXH64,
};

enum class ReplacedImageType {
	PNG,
	ZIM,
	DDS,
	BASIS,  // TODO: Might not even do this, KTX2 is a better container.
	KTX2,
	INVALID,
};

static const int MAX_REPLACEMENT_MIP_LEVELS = 12;  // 12 should be plenty, 8 is the max mip levels supported by the PSP.

enum class ReplacementState : uint32_t {
	UNLOADED,
	PENDING,
	NOT_FOUND,  // Also used on error loading the images.
	ACTIVE,
	CANCEL_INIT,
	COUNT,  // Not a valid state
};

const char *StateString(ReplacementState state);

struct GPUFormatSupport {
	bool bc123;
	bool astc;
	bool bc7;
	bool etc2;
};

struct ReplacementCacheKey {
	u64 cachekey;  // Split into two u32?
	u32 hash;

	ReplacementCacheKey() : cachekey(0), hash(0) {}
	ReplacementCacheKey(u64 ckey, u32 h) : cachekey(ckey), hash(h) {}

	bool operator ==(const ReplacementCacheKey &k) const {
		return k.cachekey == cachekey && k.hash == hash;
	}

	bool operator <(const ReplacementCacheKey &k) const {
		if (k.cachekey == cachekey) {
			return k.hash < hash;
		}
		return k.cachekey < cachekey;
	}

	// Access the parts.
	u64 CacheKey() const { return cachekey; }
	u32 ClutHash() const { return (u32)(cachekey & 0xFFFFFFFFULL); }
	u32 Address() const { return (u32)(cachekey >> 32); }
	u32 ContentsHash() const { return hash; }

	void ZeroAddress() {
		cachekey &= 0xFFFFFFFFULL;
	}
	void ZeroClutHash() {
		cachekey &= 0xFFFFFFFF00000000ULL;
	}
	void ZeroContentsHash() {
		hash = 0;
	}
};

struct ReplacementDesc {
	int newW;
	int newH;
	ReplacementCacheKey cacheKey;
	int w;
	int h;
	TextureFiltering forceFiltering;
	std::string hashfiles;
	Path basePath;
	std::vector<std::string> filenames;
	std::string logId;
	GPUFormatSupport formatSupport;
};

class ReplacedTexture;

// These aren't actually all replaced, they can also represent a placeholder for a not-found
// replacement (texture == nullptr).
struct ReplacedTextureRef {
	ReplacedTexture *texture;  // shortcut
	std::string hashfiles;  // key into levelCache_
};

// Metadata about a given texture level.
struct ReplacedTextureLevel {
	// Data dimensions
	int w = 0;
	int h = 0;
	// PSP texture dimensions
	int fullW = 0;
	int fullH = 0;

	int fullDataSize = 0;

	// To be able to reload, we need to be able to reopen, unfortunate we can't use zip_file_t.
	// TODO: This really belongs on the level in the cache, not in the individual ReplacedTextureLevel objects.
	VFSFileReference *fileRef = nullptr;
};

class ReplacedTexture {
public:
	ReplacedTexture(const ReplacedTexture &) = delete;
	ReplacedTexture &operator=(const ReplacedTexture &) = delete;
	ReplacedTexture(VFSBackend *vfs, const ReplacementDesc &desc);
	~ReplacedTexture();

	// The loader task publishes the levels with its final state (release), and the
	// emu thread only reads them once it sees that state (acquire).
	inline ReplacementState State() const {
		return (ReplacementState)retro_atomic_load_acquire_int(const_cast<retro_atomic_int_t *>(&state_));
	}

	void SetState(ReplacementState state) {
		_dbg_assert_(state != State());
		retro_atomic_store_release_int(&state_, (int)state);
	}

	void GetSize(int level, int *w, int *h) const {
		_dbg_assert_(State() == ReplacementState::ACTIVE);
		_dbg_assert_((size_t)level < levels_.size());
		*w = levels_[level].fullW;
		*h = levels_[level].fullH;
	}

	int GetLevelDataSizeAfterCopy(int level) const {
		// Includes padding etc.
		return levels_[level].fullDataSize;
	}

	size_t GetTotalDataSize() const {
		if (State() != ReplacementState::ACTIVE) {
			return 0;
		}
		size_t sz = 0;
		for (auto &data : data_) {
			sz += data.size();
		}
		return sz;
	}

	bool ForceFiltering(TextureFiltering *forceFiltering) const {
		if (desc_.forceFiltering != (TextureFiltering)0) {
			*forceFiltering = desc_.forceFiltering;
			return true;
		} else {
			return false;
		}
	}

	int NumLevels() const {
		_dbg_assert_(State() == ReplacementState::ACTIVE);
		return (int)levels_.size();
	}

	Draw::DataFormat Format() const {
		_dbg_assert_(State() == ReplacementState::ACTIVE);
		return fmt;
	}

	const ReplacementDesc &Desc() const {
		return desc_;
	}

	TextureAlpha AlphaStatus() const {
		return alphaStatus_;
	}

	// wait: block until a pending load is done, rather than checking on it.
	bool Poll(bool wait);
	bool CopyLevelTo(int level, uint8_t *out, size_t outDataSize, int rowPitch);

	std::string logId_;

private:
	enum class LoadLevelResult {
		LOAD_ERROR = 0,
		CONTINUE = 1,
		DONE = 2,
	};

	void Prepare(VFSBackend *vfs);
	// Waits for any load task, then drops all data and file references, and detaches from the VFS.
	// The texture reloads from scratch once it gets a VFS again. Must run before the VFS is deleted.
	void Unload();
	void ReleaseLevels();
	LoadLevelResult LoadLevelData(VFSFileReference *fileRef, const std::string &filename, int level, Draw::DataFormat *pixelFormat);
	void PurgeIfNotUsedSinceTime(double t);

	std::vector<std::vector<uint8_t>> data_;
	std::vector<ReplacedTextureLevel> levels_;
	// Image format of mip level 0; mixing formats across levels is not
	// allowed (container formats like KTX2/DDS manage their own mip chain).
	ReplacedImageType firstImageType_ = ReplacedImageType::INVALID;

	double lastUsed_ = 0.0;
	LimitedWaitable *threadWaitable_ = nullptr;
	Draw::DataFormat fmt = Draw::DataFormat::UNDEFINED;
	TextureAlpha alphaStatus_ = TextureAlpha::Any;
	double lastUsed = 0.0;

	retro_atomic_int_t state_{ (int)ReplacementState::UNLOADED };

	VFSBackend *vfs_ = nullptr;
	ReplacementDesc desc_;

	friend class TextureReplacer;
	friend class ReplacedTextureTask;
};