ppsspp/ext/native/gfx_es2/draw_text_android.cpp

#include "base/display.h"
#include "base/logging.h"
#include "base/stringutil.h"
#include "thin3d/thin3d.h"
#include "util/hash/hash.h"
#include "util/text/wrap_text.h"
#include "util/text/utf8.h"
#include "gfx_es2/draw_text.h"
#include "gfx_es2/draw_text_android.h"

#include "android/jni/app-android.h"
#include <assert.h>

#if PPSSPP_PLATFORM(ANDROID) && !defined(__LIBRETRO__)

#include <jni.h>

TextDrawerAndroid::TextDrawerAndroid(Draw::DrawContext *draw) : TextDrawer(draw) {
	auto env = getEnv();
	const char *textRendererClassName = "org/ppsspp/ppsspp/TextRenderer";
	jclass localClass = findClass(textRendererClassName);
	cls_textRenderer = reinterpret_cast<jclass>(env->NewGlobalRef(localClass));
	if (cls_textRenderer) {
		method_measureText = env->GetStaticMethodID(cls_textRenderer, "measureText", "(Ljava/lang/String;D)I");
		method_renderText = env->GetStaticMethodID(cls_textRenderer, "renderText", "(Ljava/lang/String;D)[I");
	} else {
		ELOG("Failed to find class: '%s'", textRendererClassName);
	}
	dpiScale_ = CalculateDPIScale();
	ILOG("Initializing TextDrawerAndroid with DPI scale %f", dpiScale_);
}

TextDrawerAndroid::~TextDrawerAndroid() {
	// Not sure why we can't do this but it crashes. Likely some deeper threading issue.
	// At worst we leak one ref...
	// env_->DeleteGlobalRef(cls_textRenderer);
	ClearCache();
}

bool TextDrawerAndroid::IsReady() const {
	return cls_textRenderer != nullptr && method_measureText != nullptr && method_renderText != nullptr;
}

uint32_t TextDrawerAndroid::SetFont(const char *fontName, int size, int flags) {
	// We will only use the default font but just for consistency let's still involve
	// the font name.
	uint32_t fontHash = hash::Adler32((const uint8_t *)fontName, strlen(fontName));
	fontHash ^= size;
	fontHash ^= flags << 10;

	auto iter = fontMap_.find(fontHash);
	if (iter != fontMap_.end()) {
		fontHash_ = fontHash;
		return fontHash;
	}

	// Just chose a factor that looks good, don't know what unit size is in anyway.
	AndroidFontEntry entry;
	entry.size = (float)(size * 1.4f) / dpiScale_;
	fontMap_[fontHash] = entry;
	fontHash_ = fontHash;
	return fontHash;
}

void TextDrawerAndroid::SetFont(uint32_t fontHandle) {
	uint32_t fontHash = fontHandle;
	auto iter = fontMap_.find(fontHash);
	if (iter != fontMap_.end()) {
		fontHash_ = fontHandle;
	} else {
		ELOG("Invalid font handle %08x", fontHandle);
	}
}

std::string TextDrawerAndroid::NormalizeString(std::string str) {
	return ReplaceAll(str, "&&", "&");
}

void TextDrawerAndroid::MeasureString(const char *str, size_t len, float *w, float *h) {
	CacheKey key{ std::string(str, len), fontHash_ };
	TextMeasureEntry *entry;
	auto iter = sizeCache_.find(key);
	if (iter != sizeCache_.end()) {
		entry = iter->second.get();
	} else {
		float scaledSize = 14;
		auto iter = fontMap_.find(fontHash_);
		if (iter != fontMap_.end()) {
			scaledSize = iter->second.size;
		} else {
			ELOG("Missing font");
		}
		std::string text(NormalizeString(std::string(str, len)));
		auto env = getEnv();
		jstring jstr = env->NewStringUTF(text.c_str());
		uint32_t size = env->CallStaticIntMethod(cls_textRenderer, method_measureText, jstr, scaledSize);
		env->DeleteLocalRef(jstr);

		entry = new TextMeasureEntry();
		entry->width = (size >> 16);
		entry->height = (size & 0xFFFF);
		sizeCache_[key] = std::unique_ptr<TextMeasureEntry>(entry);
	}
	entry->lastUsedFrame = frameCount_;
	*w = entry->width * fontScaleX_ * dpiScale_;
	*h = entry->height * fontScaleY_ * dpiScale_;
}

void TextDrawerAndroid::MeasureStringRect(const char *str, size_t len, const Bounds &bounds, float *w, float *h, int align) {
	double scaledSize = 14;
	auto iter = fontMap_.find(fontHash_);
	if (iter != fontMap_.end()) {
		scaledSize = iter->second.size;
	} else {
		ELOG("Missing font");
	}

	std::string toMeasure = std::string(str, len);
	int wrap = align & (FLAG_WRAP_TEXT | FLAG_ELLIPSIZE_TEXT);
	if (wrap) {
		bool rotated = (align & (ROTATE_90DEG_LEFT | ROTATE_90DEG_RIGHT)) != 0;
		WrapString(toMeasure, toMeasure.c_str(), rotated ? bounds.h : bounds.w, wrap);
	}

	auto env = getEnv();
	std::vector<std::string> lines;
	SplitString(toMeasure, '\n', lines);
	float total_w = 0.0f;
	float total_h = 0.0f;
	for (size_t i = 0; i < lines.size(); i++) {
		CacheKey key{ lines[i], fontHash_ };

		TextMeasureEntry *entry;
		auto iter = sizeCache_.find(key);
		if (iter != sizeCache_.end()) {
			entry = iter->second.get();
		} else {
			std::string text(NormalizeString(lines[i]));
			jstring jstr = env->NewStringUTF(text.c_str());
			uint32_t size = env->CallStaticIntMethod(cls_textRenderer, method_measureText, jstr, scaledSize);
			env->DeleteLocalRef(jstr);
			int sizecx = size >> 16;
			int sizecy = size & 0xFFFF;
			entry = new TextMeasureEntry();
			entry->width = sizecx;
			entry->height = sizecy;
			sizeCache_[key] = std::unique_ptr<TextMeasureEntry>(entry);
		}
		entry->lastUsedFrame = frameCount_;

		if (total_w < entry->width * fontScaleX_) {
			total_w = entry->width * fontScaleX_;
		}
		total_h += entry->height * fontScaleY_;
	}
	*w = total_w * dpiScale_;
	*h = total_h * dpiScale_;
}

void TextDrawerAndroid::DrawStringBitmap(std::vector<uint8_t> &bitmapData, TextStringEntry &entry, Draw::DataFormat texFormat, const char *str, int align) {
	if (!strlen(str)) {
		bitmapData.clear();
		return;
	}

	double size = 0.0;
	auto iter = fontMap_.find(fontHash_);
	if (iter != fontMap_.end()) {
		size = iter->second.size;
	} else {
		ELOG("Missing font");
	}

	auto env = getEnv();
	jstring jstr = env->NewStringUTF(str);
	uint32_t textSize = env->CallStaticIntMethod(cls_textRenderer, method_measureText, jstr, size);
	int imageWidth = (short)(textSize >> 16);
	int imageHeight = (short)(textSize & 0xFFFF);
	if (imageWidth <= 0)
		imageWidth = 1;
	if (imageHeight <= 0)
		imageHeight = 1;

	jintArray imageData = (jintArray)env->CallStaticObjectMethod(cls_textRenderer, method_renderText, jstr, size);
	env->DeleteLocalRef(jstr);

	entry.texture = nullptr;
	entry.bmWidth = imageWidth;
	entry.width = imageWidth;
	entry.bmHeight = imageHeight;
	entry.height = imageHeight;
	entry.lastUsedFrame = frameCount_;

	jint *jimage = env->GetIntArrayElements(imageData, nullptr);
	assert(env->GetArrayLength(imageData) == imageWidth * imageHeight);
	if (texFormat == Draw::DataFormat::B4G4R4A4_UNORM_PACK16 || texFormat == Draw::DataFormat::R4G4B4A4_UNORM_PACK16) {
		bitmapData.resize(entry.bmWidth * entry.bmHeight * sizeof(uint16_t));
		uint16_t *bitmapData16 = (uint16_t *)&bitmapData[0];
		for (int x = 0; x < entry.bmWidth; x++) {
			for (int y = 0; y < entry.bmHeight; y++) {
				uint32_t v = jimage[imageWidth * y + x];
				v = 0xFFF0 | ((v >> 12) & 0xF);  // Just grab some bits from the green channel.
				bitmapData16[entry.bmWidth * y + x] = (uint16_t)v;
			}
		}
	} else if (texFormat == Draw::DataFormat::R8_UNORM) {
		bitmapData.resize(entry.bmWidth * entry.bmHeight);
		for (int x = 0; x < entry.bmWidth; x++) {
			for (int y = 0; y < entry.bmHeight; y++) {
				uint32_t v = jimage[imageWidth * y + x];
				v = (v >> 12) & 0xF;  // Just grab some bits from the green channel.
				bitmapData[entry.bmWidth * y + x] = (uint8_t)(v | (v << 4));
			}
		}
	} else {
		ELOG("Bad TextDrawer format");
		assert(false);
	}
	env->ReleaseIntArrayElements(imageData, jimage, 0);
	env->DeleteLocalRef(imageData);
}

void TextDrawerAndroid::DrawString(DrawBuffer &target, const char *str, float x, float y, uint32_t color, int align) {
	using namespace Draw;
	std::string text(NormalizeString(std::string(str)));
	if (text.empty())
		return;

	CacheKey key{ std::string(str), fontHash_ };
	target.Flush(true);

	TextStringEntry *entry;

	auto iter = cache_.find(key);
	if (iter != cache_.end()) {
		entry = iter->second.get();
		entry->lastUsedFrame = frameCount_;
	} else {
		DataFormat texFormat = Draw::DataFormat::R4G4B4A4_UNORM_PACK16;

		entry = new TextStringEntry();

		TextureDesc desc{};
		std::vector<uint8_t> bitmapData;
		DrawStringBitmap(bitmapData, *entry, texFormat, text.c_str(), align);
		desc.initData.push_back(&bitmapData[0]);

		desc.type = TextureType::LINEAR2D;
		desc.format = texFormat;
		desc.width = entry->bmWidth;
		desc.height = entry->bmHeight;
		desc.depth = 1;
		desc.mipLevels = 1;
		desc.generateMips = false;
		desc.tag = "TextDrawer";
		entry->texture = draw_->CreateTexture(desc);
		cache_[key] = std::unique_ptr<TextStringEntry>(entry);
	}

	if (entry->texture) {
		draw_->BindTexture(0, entry->texture);
	}

	float w = entry->bmWidth * fontScaleX_ * dpiScale_;
	float h = entry->bmHeight * fontScaleY_ * dpiScale_;
	DrawBuffer::DoAlign(align, &x, &y, &w, &h);
	if (entry->texture) {
		target.DrawTexRect(x, y, x + w, y + h, 0.0f, 0.0f, 1.0f, 1.0f, color);
		target.Flush(true);
	}
}

void TextDrawerAndroid::ClearCache() {
	for (auto &iter : cache_) {
		if (iter.second->texture)
			iter.second->texture->Release();
	}
	cache_.clear();
	sizeCache_.clear();
}

void TextDrawerAndroid::OncePerFrame() {
	frameCount_++;
	// If DPI changed (small-mode, future proper monitor DPI support), drop everything.
	float newDpiScale = CalculateDPIScale();
	if (newDpiScale != dpiScale_) {
		// TODO: Don't bother if it's a no-op (cache already empty)
		ILOG("DPI Scale changed (%f to %f) - wiping font cache (%d items, %d fonts)", dpiScale_, newDpiScale, (int)cache_.size(), (int)fontMap_.size());
		dpiScale_ = newDpiScale;
		ClearCache();
		fontMap_.clear();  // size is precomputed using dpiScale_.
	}

	// Drop old strings. Use a prime number to reduce clashing with other rhythms
	if (frameCount_ % 23 == 0) {
		for (auto iter = cache_.begin(); iter != cache_.end();) {
			if (frameCount_ - iter->second->lastUsedFrame > 100) {
				if (iter->second->texture)
					iter->second->texture->Release();
				cache_.erase(iter++);
			} else {
				iter++;
			}
		}

		for (auto iter = sizeCache_.begin(); iter != sizeCache_.end(); ) {
			if (frameCount_ - iter->second->lastUsedFrame > 100) {
				sizeCache_.erase(iter++);
			} else {
				iter++;
			}
		}
	}
}

#endif