text: /*
   * Copyright 2013 Jeremie Roy. All rights reserved.
   * License: http://www.opensource.org/licenses/BSD-2-Clause
   */
  
  #include "common.h"
  
  #include <bgfx.h>
  #include <bx/timer.h>
  #include <bx/string.h>
  #include <bx/fpumath.h>
  
  #include "font/font_manager.h"
  #include "font/text_buffer_manager.h"
  #include "entry/input.h"
  
  #include <stdio.h>
  #include <wchar.h>
  
  long int fsize(FILE* _file)
  {
  	long int pos = ftell(_file);
  	fseek(_file, 0L, SEEK_END);
  	long int size = ftell(_file);
  	fseek(_file, pos, SEEK_SET);
  	return size;
  }
  
  TrueTypeHandle loadTtf(FontManager* _fm, const char* _filePath)
  {
  	FILE* file = fopen(_filePath, "rb");
  	if (NULL != file)
  	{
  		uint32_t size = (uint32_t)fsize(file);
  		uint8_t* mem = (uint8_t*)malloc(size+1);
  		size_t ignore = fread(mem, 1, size, file);
  		BX_UNUSED(ignore);
  		fclose(file);
  		mem[size-1] = '\0';
  		TrueTypeHandle handle = _fm->createTtf(mem, size);
  		free(mem);
  		return handle;
  	}
  
  	TrueTypeHandle invalid = BGFX_INVALID_HANDLE;
  	return invalid;
  }
  
  int _main_(int /*_argc*/, char** /*_argv*/)
  {
  	uint32_t width = 1280;
  	uint32_t height = 720;
  	uint32_t debug = BGFX_DEBUG_TEXT;
  	uint32_t reset = BGFX_RESET_VSYNC;
  
  	bgfx::init();
  
  	bgfx::reset(width, height, reset);
  
  	// Enable debug text.
  	bgfx::setDebug(debug);
  
  	// Set view 0 clear state.
  	bgfx::setViewClear(0
  		, BGFX_CLEAR_COLOR | BGFX_CLEAR_DEPTH
  		, 0x303030ff
  		, 1.0f
  		, 0
  		);
  
  	// Init the text rendering system.
  	FontManager* fontManager = new FontManager(512);
  	TextBufferManager* textBufferManager = new TextBufferManager(fontManager);
  
  	// Load some TTF files.
  	const char* fontFilePath[7] =
  	{
  		"font/droidsans.ttf",
  		"font/chp-fire.ttf",
  		"font/bleeding_cowboys.ttf",
  		"font/mias_scribblings.ttf",
  		"font/ruritania.ttf",
  		"font/signika-regular.ttf",
  		"font/five_minutes.otf",
  	};
  
  	const uint32_t numFonts = BX_COUNTOF(fontFilePath);
  
  	TrueTypeHandle fontFiles[numFonts];
  	FontHandle fonts[numFonts];
  	for (uint32_t ii = 0; ii < numFonts; ++ii)
  	{
  		// Instantiate a usable font.
  		fontFiles[ii] = loadTtf(fontManager, fontFilePath[ii]);
  		fonts[ii] = fontManager->createFontByPixelSize(fontFiles[ii], 0, 32);
  
  		// Preload glyphs and blit them to atlas.
  		fontManager->preloadGlyph(fonts[ii], L"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ. \n");
  
  		// You can unload the truetype files at this stage, but in that 
  		// case, the set of glyph's will be limited to the set of preloaded 
  		// glyph.
  		fontManager->destroyTtf(fontFiles[ii]);
  	}
  
  	TrueTypeHandle fontAwesomeTtf = loadTtf(fontManager, "font/fontawesome-webfont.ttf");
  
  	// This font doesn't have any preloaded glyph's but the truetype file 
  	// is loaded so glyph will be generated as needed.
  	FontHandle fontAwesome72 = fontManager->createFontByPixelSize(fontAwesomeTtf, 0, 72);
  
  	TrueTypeHandle visitorTtf = loadTtf(fontManager, "font/visitor1.ttf");
  
  	// This font doesn't have any preloaded glyph's but the truetype file 
  	// is loaded so glyph will be generated as needed.
  	FontHandle visitor10 = fontManager->createFontByPixelSize(visitorTtf, 0, 10);
  
  	//create a static text buffer compatible with alpha font
  	//a static text buffer content cannot be modified after its first submit.
  	TextBufferHandle staticText = textBufferManager->createTextBuffer(FONT_TYPE_ALPHA, BufferType::Static);
  
  	// The pen position represent the top left of the box of the first line 
  	// of text.
  	textBufferManager->setPenPosition(staticText, 24.0f, 100.0f);
  
  	for (uint32_t ii = 0; ii < numFonts; ++ii)
  	{
  		// Add some text to the buffer.
  		// The position of the pen is adjusted when there is an endline.
  		textBufferManager->appendText(staticText, fonts[ii], L"The quick brown fox jumps over the lazy dog\n");
  	}
  
  	// Now write some styled text.
  
  	// Setup style colors.
  	textBufferManager->setBackgroundColor(staticText, 0x551111ff);
  	textBufferManager->setUnderlineColor(staticText, 0xff2222ff);
  	textBufferManager->setOverlineColor(staticText, 0x2222ffff);
  	textBufferManager->setStrikeThroughColor(staticText, 0x22ff22ff);
  
  	// Background.
  	textBufferManager->setStyle(staticText, STYLE_BACKGROUND);
  	textBufferManager->appendText(staticText, fonts[0], L"The quick ");
  
  	// Strike-through.
  	textBufferManager->setStyle(staticText, STYLE_STRIKE_THROUGH);
  	textBufferManager->appendText(staticText, fonts[0], L"brown fox ");
  
  	// Overline.
  	textBufferManager->setStyle(staticText, STYLE_OVERLINE);
  	textBufferManager->appendText(staticText, fonts[0], L"jumps over ");
  
  	// Underline.
  	textBufferManager->setStyle(staticText, STYLE_UNDERLINE);
  	textBufferManager->appendText(staticText, fonts[0], L"the lazy ");
  
  	// Background + strike-through.
  	textBufferManager->setStyle(staticText, STYLE_BACKGROUND | STYLE_STRIKE_THROUGH);
  	textBufferManager->appendText(staticText, fonts[0], L"dog\n");
  
  	textBufferManager->setStyle(staticText, STYLE_NORMAL);
  	textBufferManager->appendText(staticText, fontAwesome72, L"\xf011 \xf02e \xf061 \xf087 \xf0d9 \xf099 \xf05c \xf021 \xf113\n");
  
  	// Create a transient buffer for real-time data.
  	TextBufferHandle transientText = textBufferManager->createTextBuffer(FONT_TYPE_ALPHA, BufferType::Transient);
  
  	while (!entry::processEvents(width, height, debug, reset) )
  	{
  		// This dummy draw call is here to make sure that view 0 is cleared
  		// if no other draw calls are submitted to view 0.
  		bgfx::submit(0);
  
  		int64_t now = bx::getHPCounter();
  		static int64_t last = now;
  		const int64_t frameTime = now - last;
  		last = now;
  		const double freq = double(bx::getHPFrequency() );
  		const double toMs = 1000.0 / freq;
  
  		// Use debug font to print information about this example.
  		bgfx::dbgTextClear();
  		bgfx::dbgTextPrintf(0, 1, 0x4f, "bgfx/examples/10-font");
  		bgfx::dbgTextPrintf(0, 2, 0x6f, "Description: Use the font system to display text and styled text.");
  		bgfx::dbgTextPrintf(0, 3, 0x0f, "Frame: % 7.3f[ms]", double(frameTime)*toMs);
  
  		// Use transient text to display debug information.
  		wchar_t fpsText[64];
  		bx::swnprintf(fpsText, BX_COUNTOF(fpsText), L"Frame: % 7.3f[ms]", double(frameTime) * toMs);
  
  		textBufferManager->clearTextBuffer(transientText);
  		textBufferManager->setPenPosition(transientText, width - 150.0f, 10.0f);
  		textBufferManager->appendText(transientText, visitor10, L"Transient\n");
  		textBufferManager->appendText(transientText, visitor10, L"text buffer\n");
  		textBufferManager->appendText(transientText, visitor10, fpsText);
  
  		float at[3]  = { 0, 0,  0.0f };
  		float eye[3] = { 0, 0, -1.0f };
  
  		float view[16];
  		bx::mtxLookAt(view, eye, at);
  
  		const float centering = 0.5f;
  
  		// Setup a top-left ortho matrix for screen space drawing.
  		const bgfx::HMD* hmd = bgfx::getHMD();
  		if (NULL != hmd)
  		{
  			float proj[16];
  			bx::mtxProj(proj, hmd->eye[0].fov, 0.1f, 100.0f);
  
  			static float time = 0.0f;
  			time += 0.05f;
  
  			const float dist = 10.0f;
  			const float offset0 = -proj[8] + (hmd->eye[0].viewOffset[0] / dist * proj[0]);
  			const float offset1 = -proj[8] + (hmd->eye[1].viewOffset[0] / dist * proj[0]);
  
  			float ortho[2][16];
  			const float offsetx = width/2.0f;
  			bx::mtxOrtho(ortho[0], centering, offsetx + centering, height + centering, centering, -1.0f, 1.0f, offset0);
  			bx::mtxOrtho(ortho[1], centering, offsetx + centering, height + centering, centering, -1.0f, 1.0f, offset1);
  			bgfx::setViewTransform(0, view, ortho[0], BGFX_VIEW_STEREO, ortho[1]);
  			bgfx::setViewRect(0, 0, 0, hmd->width, hmd->height);
  		}
  		else
  		{
  			float ortho[16];
  			bx::mtxOrtho(ortho, centering, width + centering, height + centering, centering, -1.0f, 1.0f);
  			bgfx::setViewTransform(0, view, ortho);
  			bgfx::setViewRect(0, 0, 0, width, height);
  		}
  
  		// Submit the debug text.
  		textBufferManager->submitTextBuffer(transientText, 0);
  
  		// Submit the static text.
  		textBufferManager->submitTextBuffer(staticText, 0);
  
  		// Advance to next frame. Rendering thread will be kicked to
  		// process submitted rendering primitives.
  		bgfx::frame();
  	}
  
  	fontManager->destroyTtf(fontAwesomeTtf);
  	fontManager->destroyTtf(visitorTtf);
  
  	// Destroy the fonts.
  	fontManager->destroyFont(fontAwesome72);
  	fontManager->destroyFont(visitor10);
  	for (uint32_t ii = 0; ii < numFonts; ++ii)
  	{
  		fontManager->destroyFont(fonts[ii]);
  	}
  
  	textBufferManager->destroyTextBuffer(staticText);
  	textBufferManager->destroyTextBuffer(transientText);
  
  	delete textBufferManager;
  	delete fontManager;
  
  	// Shutdown bgfx.
  	bgfx::shutdown();
  
  	return 0;
  }
  