Poor CPU Performance about raylib HOT 6 CLOSED

After further investigation, it seems that high (100% or 25% for quad-cores) CPU usage is the expected behavior for most cases in OpenGL/Direct3D games, it mainly depends on graphics driver implementation. Game loop just keeps running all the time if not locked in any way. In GLFW3 is possible to glfwWaitEvents() instead of glfwPollEvent() so frame swap can be locked waiting for events and CPU usage falls to ~1% but that's not the desired behaviour in a game. Enabling VSYNC could have a similar effect but it also depends on graphics driver...

A couple of links with further info:

http://stackoverflow.com/questions/18365269/cpu-usage-is-high-when-using-opengl-control-class
http://gamedev.stackexchange.com/questions/19066/why-is-opengl-using-100-cpu-shortly-after-start-up-when-wglswapintervalext-is-e

from raylib.

Having an option in the lib API for vsync might help allot. When vendor drivers have trouble with vsync, the opengl software can make up for that and override the driver settings.

#ifdef _WIN32
    // Turn on vertical screen sync under Windows.
    // (I.e. it uses the WGL_EXT_swap_control extension)
    typedef BOOL (WINAPI *PFNWGLSWAPINTERVALEXTPROC)(int interval);
    PFNWGLSWAPINTERVALEXTPROC wglSwapIntervalEXT = NULL;
    wglSwapIntervalEXT = (PFNWGLSWAPINTERVALEXTPROC)wglGetProcAddress("wglSwapIntervalEXT");
    if(wglSwapIntervalEXT)
        wglSwapIntervalEXT(1);
#endif

from raylib.

GLFW already uses WGL_EXT_swap_control extension to provide VSYNC (where this extension is available) but, again, it can be overriden by graphic driver, forcing on or off. Here it is further information on Swap Internal:

https://www.opengl.org/wiki/Swap_Interval

But there is something I can do; I can expose GLFW VSYNC mechanism to raylib users through a flag, to be set before windows creation. That way users can try forcing VSYNC and wait for the driver to respond.

I'm working on it.

from raylib.

Thank you for the time and effort you have put into this.

from raylib.

Use function: SetConfigFlags(FLAG_VSYNC_HINT); // Use before InitWindow()

Underlying system, GLFW3, will try to enable vsync if graphic driver allows it.

Upcoming raylib v1.3 includes this change.

from raylib.

Issue corrected on commit b681e8c.

from raylib.