I was always unsure, what does the restrict keyword mean in C++? Does it mean the two or more pointer given to the function does not overlap? What else does it mean? In his paper, Memory Optimization, Christer Ericson says that while restrict is not part of the C++ standard yet, that it is supported by many compilers and he recommends it's usage when available: restrict keyword ! Ne
我总是不确定,C ++中的restrict关键字是什么意思? 这是否意味着给函数的两个或多个指针不重叠? 这是什么意思? Christer Ericson在他的论文“内存优化”中说,虽然restrict并不是C ++标准的一部分,但它被许多编译器支持,而且他建议在可用时使用它: 限制关键字 ! 1999年新的ANSI / ISO C标准 ! 目前还不在C ++标准中,但被许多C ++编译器支持 ! 只有一个提示,所以可能什么也不做,仍然是一致的 限制合
I want to draw/paint on a webcam screen using OpenCV. Since I'm reading from a cam, the frames are constantly changing, so I'm trying to figure out a way to keep or save the drawing on the current frame and use it for the next frame. The code below allows you to draw on the screen but when it gets the next frame, the drawing is gone and it starts over. Could someone please help me ...
我想使用OpenCV在网络摄像头屏幕上绘制/绘制。 由于我是从凸轮读取的,所以这些帧不断变化,所以我试图找出一种方法来保存或保存当前帧上的图形,并将其用于下一帧。 下面的代码允许你在屏幕上绘图,但是当它到达下一帧时,绘图消失并重新开始。 有人可以帮助我...谢谢。 CvCapture *input; input = cvCaptureFromCAM( 0 ); cvSetMouseCallback("Demo",&on_mouse, 0);
I have heard that somewhere @ web I'll be able to find good C++ example of Mediator working with GUI components. But I menaged to find only that GoF sample or things from sorcemaking and similar that aren't helpful to me. So... do you know where that mentioned GUI sample can be found? Sorry for that kind of question, but that can be useful for others too. How about this one: http:/
我听说在某个地方,我可以找到使用GUI组件的Mediator的良好C ++示例。 但我试图找到只有GoF的样品或制造巫术的东西以及类似的东西,这对我没有帮助。 所以......你知道那里提到的GUI样本可以找到吗? 对不起,这样的问题,但也可以用于其他人。 这个怎么样:http://www.andypatterns.com/index.php/design_patterns/model_gui_mediator_pattern/。 看起来作者正在将该模式专门应用于GUI功能的“视图”部分(而不是其背后的
I am working with code that has a global static variable (which is an object) and I need access to it from another class. I have always avoided global variables/functions in general so in this situation I am not sure how to go about it properly. Just to clear my understand of things, in a global static variable has internal linkage, which means that any source file that includes this particula
我正在使用具有全局静态变量(这是一个对象)的代码,我需要从另一个类访问它。 我一直总是避免使用全局变量/函数,所以在这种情况下我不确定如何正确地执行它。 为了清楚我对事物的理解,在全局静态变量中有内部链接,这意味着包含这个特定头文件的任何源文件都将获得它自己的变量副本? 编辑:我到目前为止所尝试的是使一个函数返回变量的地址。 不幸的是,这似乎并没有奏效。 // names were changed but the code is as
I use a VirtualTreeView in C++ Builder and use it with structure like this: struct TVTNodeData { int Index; UnicodeString Caption; } I pre-fill nodes of the tree using loop that has this: TVirtualNode *Node = VTree->AddChild(NULL); pNode = (TVTNodeData *)VTree->GetNodeData(Node); pNode->Index = 1; pNode->Caption = "Whatever"; I noticed that the memory for the applicati
我在C ++ Builder中使用了VirtualTreeView,并将其用于这样的结构: struct TVTNodeData { int Index; UnicodeString Caption; } 我使用循环预先填充树的节点: TVirtualNode *Node = VTree->AddChild(NULL); pNode = (TVTNodeData *)VTree->GetNodeData(Node); pNode->Index = 1; pNode->Caption = "Whatever"; 我发现应用程序的内存不断增加(内存泄漏),即使我清除树并重新加载它。 此页面 -
I am making a program with OpenGL that renders frames in the GPU, which I then transfer to memory so I can use them in another program. I have no need for a window or render to screen, so I am using GLFW but with a hidden window and context. Following opengl-tutorial.com I set up a Framebuffer with a texture and a depth renderbuffer so I can render to the texture and then read it's pixels.
我正在用OpenGL制作一个程序,在GPU中渲染帧,然后将其传输到内存中,以便我可以在另一个程序中使用它们。 我不需要窗口或渲染器来显示,所以我使用GLFW,但是有一个隐藏的窗口和上下文。 在opengl-tutorial.com之后,我设置了一个带有纹理和深度渲染缓冲区的Framebuffer,这样我就可以渲染纹理,然后读取它的像素。 只是为了检查一些东西,我可以使窗口可见,并将纹理渲染回四边形的屏幕上,并使用直通着色器。 我的问题是
I'm trying to draw a waveform from a raw audio file. I demuxed/decoded an audio file using FFmpeg and I have those informations: samples buffer, the size of the samples buffer, the duration of the audio file (in seconds), sample rate (44100, 48000, etc), sample size, sample format (uint8, int16, int32, float, double), and the raw audio data itself. Digging on the Internet I found this algo
我试图从原始音频文件中绘制波形。 我使用FFmpeg对音频文件进行了解复用/解码,并且我有这些信息:采样缓冲区,采样缓冲区的大小,音频文件的持续时间(以秒为单位),采样率(44100,4800等),采样大小,采样格式(uint8,int16,int32,float,double)和原始音频数据本身。 在互联网上挖掘我发现这个算法(更多): 白噪声: 算法 你所需要做的就是随机化每个样本从幅度到幅度。 我们不关心大多数情况下的通道数量
I would like to generate waveforms which show the low, mid and high frequencies together: ala traktor for ipad http://www.dawsons.co.uk/blog/wp-content/uploads/2013/02/TRAKTOR_DJ_main-2_L.jpg I have managed to get frequency data of the audio using fft, then sum up the amplitudes in the bins based on frequency ranges (low: 0 - 300Hz, mid: 300 - 2000Hz, high: 2000Hz +) but when plotted these do n
我想生成一起显示低频,中频和高频的波形:ala traktor for ipad http://www.dawsons.co.uk/blog/wp-content/uploads/2013/02/TRAKTOR_DJ_main-2_L.jpg 我已经设法使用fft获得音频的频率数据,然后基于频率范围(低:0-300Hz,中:300-2000Hz,高:2000Hz +)来总结频段中的幅度,但是当绘制时它们不相似相同声音的平常RMS图。 有人能给我一个关于Traktor波形如何生成的指针吗? 非常感谢! 我不会使用FFT数据来做这么简
I'm new to SDL. I'm developing a media player using SDL, and now I met the problem that the audio callback function is sometimes not called in time, and cause the audio a little fitful. I use such piece of code to open the audio device: wanted_spec.xxx = xxx; wanted_spec.callback = audio_callback; //audio_callback is my audio callback function SDL_OpenAudio(&wanted_spec, &s
我是SDL新手。 我正在开发一款使用SDL的媒体播放器,现在我遇到了音频回调函数有时不能及时调用的问题,并导致音频稍微有些紧张。 我使用这样的代码来打开音频设备: wanted_spec.xxx = xxx; wanted_spec.callback = audio_callback; //audio_callback is my audio callback function SDL_OpenAudio(&wanted_spec, &spec); 我的操作系统是Windows XP。 你知道这件事吗? 有人可以建议如何将数据馈送与回调函
In c++, when and how do you use a callback function? EDIT: I would like to see a simple example to write a callback function. Note: Most of the answers cover function pointers which is one possibility to achieve "callback" logic in C++, but as of today not the most favourable one I think. What are callbacks(?) and why to use them(!) A callback is a callable (see further down)
在c ++中,何时以及如何使用回调函数? 编辑: 我想看一个简单的例子来编写一个回调函数。 注意:大部分答案都包含了函数指针,这是C ++中实现“回调”逻辑的一种可能,但到目前为止,并不是我认为最有利的一种。 什么是回调(?)以及为什么要使用它们(!) 回调是类或函数接受的可调用的函数(详见下文),用于根据回调来定制当前的逻辑。 使用回调的一个原因是编写与被调用函数中的逻辑无关的通用代码,并且可以通