Messages

1

Window / Window and multiple threads

« on: September 19, 2011, 11:07:17 pm »

thanks, that explains everything. i believe this should be mentioned in the docs.

2

Window / Window and multiple threads

« on: September 19, 2011, 10:47:10 pm »

then appearently i am doing something really wrong as the window does not seem to generate any events this way

3

Window / Window and multiple threads

« on: September 19, 2011, 10:15:50 pm »

i dont. i want to draw in one thread and poll events in another. but it appears that i still need the window to be active to poll events from it.

4

Window / Window and multiple threads

« on: September 19, 2011, 08:42:39 pm »

Would doing that really often (like every frame) introduce huge overhead?

5

Window / Window and multiple threads

« on: September 19, 2011, 07:51:15 pm »

I have a thread one where i create the window:

Code: [Select]

sf::Window* wnd = new sf::Window(sf::VideoMode(400, 300), "some title", sf::Style::Close);
Then i pass the wnd ponter to two other threads.
In thread two i query window for events:

Code: [Select]

sf::Event event;
while (true)
    while(wnd->PollEvent(event))
    {
         //....
    }
And in thread three I draw in it:

Code: [Select]

while (true)
{
    //...
    wnd->Display();
}

The window is of course protected by proper locking.

This causes lots of

Failed to activate window's context

messages to the console. Is what i am trying to do even possible?

6

Graphics / RenderTarget::ConvertCoords backwards

« on: September 12, 2011, 08:33:30 pm »

I wanted to draw some text in RenderWindow that would be positioned near a sprite, like a label or tag always moving along with the sprite, attached to some point of it and not rotating or scaling regardless of sprite's transformations. And I was really surprised to not find a complementary function to ConvertCoords, that would convert world coordinates to screen coordinates. I believe this to be a frequently occuring task and i guess it is only reasonable to add such functionality to RenderTarget

7

Window / Event::MouseWheelEvent::Delta bug

« on: September 11, 2011, 09:38:08 am »

Under windows/sfml2 i enountered a problem where  Event::MouseWheelEvent::Delta is almost allways zero, you need to scroll the wheel REALLY fast to obtain some other sensible value. After taking a look at the ProcessEvent function in /src/SFML/Window/Win32/WindowImplWin32.cpp, i found this:

Code: [Select]


        // Mouse wheel event
        case WM_MOUSEWHEEL :
        {
            // Mouse position is in screen coordinates, convert it to window coordinates
            POINT position;
            position.x = static_cast<Int16>(LOWORD(lParam));
            position.y = static_cast<Int16>(HIWORD(lParam));
            ScreenToClient(myHandle, &position);

            Event event;
            event.Type = Event::MouseWheelMoved;
            event.MouseWheel.Delta = static_cast<Int16>(HIWORD(wParam)) / 120;
            event.MouseButton.X    = position.x;
            event.MouseButton.Y    = position.y;
            PushEvent(event);
            break;
        }


Now, after carefully reading http://msdn.microsoft.com/en-us/library/ms645617(v=vs.85).aspx, the following was noticed:

The high-order word indicates the distance the wheel is rotated, expressed in multiples or divisions of WHEEL_DELTA, which is 120.

so it becomes appearent that

Code: [Select]

event.MouseWheel.Delta = static_cast<Int16>(HIWORD(wParam)) / 120;
sets Delta to zero whenever the absolute value of HIWORD(wParam) is less than 120, which happens to be quite often.

After taking a look at the Linux implementation:

Code: [Select]

event.MouseWheel.Delta = windowEvent.xbutton.button == Button4 ? 1 : -1; which can return only 1 or -1 i believe the windows one should be changed to something like

Code: [Select]

event.MouseWheel.Delta = static_cast<Int16>(HIWORD(wParam)) > 0 ? 1 : -1;
as well, or make Delta a float to allow fractional values.