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I am having problems when I change between  Landscape and Portrait modes under IOS and Android. I have Portrait and Landscape modes allowed for both. I am setting the new aspect ratio of the camera and calling glViewport with the new resolution. In my case Portrait is 640x1136 and Landscape is the reverse 1136x640 .

This is how I am handling it at the moment. Is that the correct way of doing it with SDL ?

SDL_DisplayMode displayMode;
SDL_GetDesktopDisplayMode(0, &displayMode);

SDL_Window* window = SDL_CreateWindow(NULL, 0, 0, displayMode.w, displayMode.h, SDL_WINDOW_OPENGL | SDL_WINDOW_FULLSCREEN | SDL_WINDOW_RESIZABLE);

SDL_GLContext gl = SDL_GL_CreateContext(window);

...

float width = displayMode.w;

float height = displayMode.h;


float aspect = width/height;
m_pCamera->SetAspect(aspect);

glViewport(0, 0, width, height);

while(game->running)
{
     while (SDL_PollEvent(&event)) {
            if (event.type == SDL_WINDOWEVENT && event.window.event == SDL_WINDOWEVENT_RESIZED)
            {
                width = event.window.data1;
                height = event.window.data2;
               
                aspect = width/height;
                m_pCamera->SetAspect(aspect);

                glViewport(0, 0, width, height);
            }
}

...


This is my end result where in Portrait the Model is bigger compared to Landscape.

The SDL output makes sense; the image on the Portrait screen is the same as the Landscape one, but scaled vertically, with the viewport obscuring most of the left and right hand sides. I would check the middleware you're using to set the projection matrix; you're probably going to have to do more than just set the aspect ratio to get the effect you're looking for.



On 20 July 2014 05:31, Alexander Chaliovski wrote:

I am out of options I was trying to compensate with the Camera field of view but I couldn't get the ratio properly.  Is there an SDL function that can help for this. Maybe I can do something like crop to fit ?

Not really. SDL has minimal interaction with OpenGL, mostly from the window-management side of things. The issue you're having is caused by the projection matrix set up by your Camera object middleware, which is responsible for mapping the field-of-view in world space to normalized screen coordinates. Perhaps if you can tell us what middleware you're using, the initial setup of your m_pCamera object (cropped out in your original post), and a diagram of how you want things to look on screen, we might be able to assist.



On 20 July 2014 17:00, Alexander Chaliovski wrote: