OpenGL 和 SDL，在保持内部分辨率不变的情况下调整窗口大小？
我正在 OpenGL 中做一个游戏，并使用 SDL 来管理窗口、设置图标以及所有这些东西。 现在我已经将场景渲染设置为帧缓冲区，我想知道是否可以在保持起始 GL 设置的同时调整 SDL 窗口的大小（我正在尝试模拟精确的分辨率，因此窗口大小调整是将帧缓冲区重新调整为窗口大小）
我尝试将 SDL 窗口的分辨率设置为我传递给 glortho 的分辨率的两倍，但它给出了意想不到的结果©。这是否可能，或者我是否需要始终将工作分辨率调整为屏幕分辨率？ 我使用此代码来初始化视频
SDL_SetVideoMode(XRES, YRES, bpp, SDL_OPENGL | SDL_HWPALETTE);
gl_init(XRES,YRES);
，并在 gl_init 中将 glortho 设置为 glOrtho(0, width, 0, height, -1, 1)，然后将帧缓冲区“空白”纹理的大小设置为宽度和高度。
当像上面那样调用该函数时，一切都很好。但是，如果我尝试类似的方法，
SDL_SetVideoMode(XRES*2, YRES*2, bpp, SDL_OPENGL | SDL_HWPALETTE);
gl_init(XRES,YRES);
而不是得到预期的结果（缩放输出），我会发现输出位于 X 轴最左侧的某个位置和 Y 轴中间的某个位置，就像 GL 大小甚至大于屏幕，其余部分被裁剪掉。我有什么遗漏的吗？
I am doing a game in OpenGL and using SDL for managing the window, setting the icons, and all that stuff.
Now that I have set rendering the scene to a framebuffer, I wondered if I could resize the SDL window while keeping my starting GL settings (I am trying to emulate a exact resolution so window resizing is a rescale of the framebuffer to the window size)
I tried giving the SDL window double the resolution of the resolution I pass to glortho, but it gives unexpected results©. Is this possible at all, or do I need to adapt my working resolution to the screen resolution all the time?
I use this code to initialize video
SDL_SetVideoMode(XRES, YRES, bpp, SDL_OPENGL | SDL_HWPALETTE);
gl_init(XRES,YRES);
And into gl_init I set glortho to glOrtho(0, width, 0, height, -1, 1), and then the framebuffer "blank" texture to width and height in size, as well.
When the function is called as above, all is well. But if I try something like
SDL_SetVideoMode(XRES*2, YRES*2, bpp, SDL_OPENGL | SDL_HWPALETTE);
gl_init(XRES,YRES);
Instead of getting my expected results (scaled output) I find out that the output is somewhere at the far left on X axis and somewhere in the middle of the Y axis, like if GL size was even bigger than the screen and the rest was cropped out. Is there anything I am missing?
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尝试简单地将FBO纹理大小设置为窗口大小的1/4（其边缘长度的1/2），然后将FBO的颜色缓冲区纹理渲染到整个SDL窗口。
Try to simply set the FBO texture size to 1/4 of the window size (1/2 of its edge lengths), then render the FBO's color buffer texture to the entire SDL window.
我知道这是一个老问题，但它是谷歌上的最高结果，并且没有答案。
您需要调用
glViewport()。假设您希望内部分辨率为 1024x768，窗口分辨率为 windowWidth 和 windowHeight。在写入 FBO 之前，请调用glViewport(0, 0, 1024, 768)。然后，在将 FBO 写入窗口之前，调用glViewport(0, 0, windowWidth, windowHeight)。I know this is an old question, but it is a top result on Google and does not have an answer.
You'll need to call
glViewport(). Suppose you want your internal resolution as 1024x768, and your window resolution is windowWidth and windowHeight. Before you write to your FBO, callglViewport(0, 0, 1024, 768). Then, before writing your FBO to the window, callglViewport(0, 0, windowWidth, windowHeight).您在游戏循环中使用此代码
You use this code in your game loop