准备
配置dll和lib 我就不细说了可以模仿我demo用cmake配置
头文件放SDL.h同一个目录
sample.ttf SourceSansPro-Regular 字体文件
目的
使用ttf字体文件 进行文字的渲染
也就是使用ttf文件 自定义文字的字体显示
主要绘制一行"Shiver Is Best Awesome"消息文本
初始化,创建窗口、渲染器等
TTF_Init() tif初始化
//Start up SDL and make sure it went ok if (SDL_Init(SDL_INIT_VIDEO) != 0) { logSDLError(std::cout, "SDL_Init"); return 1; } //Also need to init SDL_ttf if (TTF_Init() != 0) { logSDLError(std::cout, "TTF_Init"); SDL_Quit(); return 1; } //Setup our window and renderer SDL_Window* window = SDL_CreateWindow("Lesson 6", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, SCREEN_WIDTH, SCREEN_HEIGHT, SDL_WINDOW_SHOWN); if (window == nullptr) { logSDLError(std::cout, "CreateWindow"); TTF_Quit(); SDL_Quit(); return 1; } SDL_Renderer* renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC); if (renderer == nullptr) { logSDLError(std::cout, "CreateRenderer"); cleanup(window); TTF_Quit(); SDL_Quit(); return 1; }
载入字体内容并绘制
绘制文字需要：
1.消息文本message
2.字体文件fontFile
3.字体颜色color
4.字体大小fontSize
const std::string resPa th = getResourcePath("Lesson6"); //We'll render the string "TTF fonts are cool!" in white //Color is in RGB format SDL_Color color = { 255, 255, 255, 255 }; SDL_Texture* image = renderText("Shiver is best Aswsome", "..\\..\\res\\06sdl_learn\\sample.ttf", color, 64, renderer); if (image == nullptr) { cleanup(image, renderer, window); TTF_Quit(); SDL_Quit(); return 1; }
绘制字体过程：
1.打开字体文件
2.先根据render,message,color 创建Surface
3.使用Surface创建Texture
SDL_Texture* renderText(const std::string& message, const std::string& fontFile, SDL_Color color, int fontSize, SDL_Renderer* renderer) { //Open the font TTF_Font* font = TTF_OpenFont(fontFile.c_str(), fontSize); if (font == nullptr) { logSDLError(std::cout, "TTF_OpenFont"); return nullptr; } //We need to first render to a surface as that's what TTF_RenderText returns, then //load that surface into a texture SDL_Surface* surf = TTF_RenderText_Blended(font, message.c_str(), color); if (surf == nullptr) { TTF_CloseFont(font); logSDLError(std::cout, "TTF_RenderText"); return nullptr; } SDL_Texture* texture = SDL_CreateTextureFromSurface(renderer, surf); if (texture == nullptr) { logSDLError(std::cout, "CreateTexture"); } //Clean up the surface and font SDL_FreeSurface(surf); TTF_CloseFont(font); return texture; }
