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c++glfwopengl-3

How to determine size of the drawable area of an OpenGL 3.3 window using GLFW

I'm trying to create an game / application using GLFW and OpenGL 3.3. I'd like to be able to detect collision with the sides of the window, but it seems that the drawable area of the window differs from the size of the window set using glfwCreateWindow().

So my question is, how do I get that drawable area, ie. the size of the window minus the border? I'd rather not have to use the WinAPI so as to make it more cross-platform, and glfwGetWindowFrameSize() is in GLFW 3.1, which isn't completed yet.

Edit: My question makes it seem like I need to use GLFW do accomplish this, which isn't true. I just wanted to note that I'm using GLFW as a window / input handler.

Solution

  • You want glfwGetFramebufferSize.

    glfwGetVideoMode returns the video mode of the specified monitor, not the size of your window. For fullscreen windows, they happen to be the same, but for other windows they are likely to be very different.