SDL库自适应窗口大小及遇到的坑

烈日下的奔跑2024-08-15 18:43

一、窗口尺寸改变大小时，视频卡住不动

网上介绍的方法有：

1：修改源码中的代码！

SDL_OnWindowResized中的SDL_WINDOWEVENT_SIZE_CHANGED更改为SDL_WINDOWEVENT_RESIZED

2：SDL_EventState(SDL_WINDOWEVENT, SDL_IGNORE);

我都试过了，确实可以实现，但是牺牲了分辨率，视频边的模糊

我总结了方法，既然不信那就重新创建SDL_Window、SDL_Renderer、SDL_Texture呗，再利用事件即可解决

cpp 复制代码

void SDLRender::_HandleEventProc()
{
	std::string str = "1";
	while (true)
	{
		SDL_Event event;
		if (SDL_PollEvent(&event))
		{
			switch (event.type)
			{
			case SDL_WINDOWEVENT:
				switch (event.window.event)
				{
				case SDL_WINDOWEVENT_RESIZED:
				case SDL_WINDOWEVENT_SIZE_CHANGED:
					m_nScaleWidth = event.window.data1;
					m_nScaleHeight = event.window.data2;
					if (m_SdlWindow)
					{
						SDL_DestroyWindow(m_SdlWindow);
						m_SdlWindow = nullptr;
					}
					if (m_SdlTexture)
					{
						SDL_DestroyTexture(m_SdlTexture);
						m_SdlTexture = nullptr;
					}
					if (m_SdlRender)
					{
						SDL_DestroyRenderer(m_SdlRender);
						m_SdlRender = nullptr;
					}

					if (!m_SdlWindow)
						m_SdlWindow = SDL_CreateWindowFrom(m_hwnd);
					if (!m_SdlRender)
						m_SdlRender = SDL_CreateRenderer(m_SdlWindow, -1, SDL_RendererFlags::SDL_RENDERER_ACCELERATED);
					break;
				default:
					break;
				}
				break;
			default:
				break;
			}
		}
	}
}

只要检测到窗口尺寸变化就重新创建。

二、播放不同分辨率视频会崩溃

解决办法：检测到不用分辨率的帧重新创建SDL_CreateTexture

cpp 复制代码

		if (m_SdlTexture)
		{
			SDL_DestroyTexture(m_SdlTexture);
			m_SdlTexture = nullptr;
		}
		m_SdlTexture = SDL_CreateTexture(m_SdlRender, GetSDLFormat((AVPixelFormat)frame->format), SDL_TEXTUREACCESS_STREAMING, frame->width, frame->height);

有不足指出还请指教。。。。