Topics

1

DotNet / SFML and event management (solved)

« on: March 14, 2017, 12:11:36 am »

Consider the following (very simple) SFML app.
It creates a render window, poll events and print to console each mouse move position:

public static void Main()
{                      
        RenderWindow window = new RenderWindow(new VideoMode(800, 600), "SFML window");
       
        window.MouseMoved += (sender, e) => {
                Console.WriteLine(e.X + " " + e.Y);
        };
                       
        // Start the game loop
        while (window.IsOpen())
        {
                window.DispatchEvents();                                               
                window.Clear();                        
                window.Display();
                //System.Threading.Thread.Sleep(1000);
        }
}

Imagine we remove the line in comment (Thread.Sleep(...)).
Now the display in the console is very laggy (which is expected).

However it only prints one mouse position per second. I would rather expect that it would wait one second, then print a bunch of mouse positions (actually all the ones send to the window while sleeping), then wait one second , then print some messages and so on.

I have taken a look at source code (both C++ and C# github repos) and AFAIK SFML behavior is to pump all messages from the window (using PeekMessageW()) then store in it's own queue (a C++ vector) and dispatch them one by one. So I don't understand behavior that I got. I expect Console.WriteLine() to be called several times between two Thread.Sleep().

2

DotNet / All sprites displayed as white squares after migrating for SFML.NET 2.1 to 2.2

« on: March 09, 2017, 07:09:30 pm »

I have a perfectly working application made with SFML.Net 2.1. I have decided to migrate to 2.2.

However, after the migration I have noticed the following : ALL sprites are now displayed as white rectangles (no more textures)

I have reduce program to the bare minimum and problem still occurs :

public static void Main()
{
        RenderWindow window = new RenderWindow(new VideoMode(800, 600), "SFML window");
       
        window.Closed += OnClosed;
        Sprite spr = new Sprite(new Texture(@"test.png"));     
                       
        while (window.IsOpen)
        {
                window.DispatchEvents();                                                       
                window.Clear();                                
                window.Draw(spr);
                window.Display();
        }
}

   

Issue is not related to test.png file : if it was not there it would throw an exception.

Compiling the exact same program under SFML 2.1 (expect minor changes like window.Open vs window.Open()) => it works perfectly (sprites are displayed as they should).

At runtime, the following errors are sometimes shown when using SFML 2.2 :

Code: [Select]

OpenGL Warning: SHCRGL_GUEST_FN_WRITE_READ (36) failed with ffffffdb ffffffea   

Code: [Select]

Unhandled Exception: System.AccessViolationException: Attempted to read or write
 protected memory. This is often an indication that other memory is corrupt.
   at SFML.Graphics.Sprite.sfRenderWindow_drawSprite(IntPtr CPointer, IntPtr Spr
ite, MarshalData& states)
   at SFML.Graphics.Sprite.Draw(RenderTarget target, RenderStates states)
   at SFML.Graphics.RenderWindow.Draw(Drawable drawable)
   at Test.Program.Main() in Program.cs:line 22   

I use SFML.Net 2.2 32-bit version from here : http://www.sfml-dev.org/download/sfml.net/ + CSFML 2.2 from here : http://www.sfml-dev.org/download/csfml/

3

Graphics / How to draw a line strip that has some thickness

« on: March 04, 2017, 11:19:42 am »

I would like to draw a line made of several points (more than 2) and that have some thickness (aka width).

How can I do that in SFML ?

Here is my actual code (C#) :

Vertex[] line =
{
        new Vertex(new Vector2f(10.0f, 10.0f)),
        new Vertex(new Vector2f(150.0f, 150.0f)),
        new Vertex(new Vector2f(300.0f, 60.0f))
};

window.Draw(line, PrimitiveType.LinesStrip);

4

General / Which SFML package to install from NuGet ?

« on: February 17, 2017, 02:48:56 pm »

When I search "SFML" on NuGet I got the following packages :

- "SFML.Net" (2.1.5) By Laurent G

However there is also the following ones :

sfml-system
sfml-window
sfml-graphics
sfml-audio
sfml-network

They are also by Laurent G. but version is 2.4.0

Should I install "SFML.Net" package (which is outdated) or the individual (more recent) packages (only the one I need) ?
If it's better to install the individual packages, what is the purpose of "SFML.Net" package ?

5

Graphics / How to check if a sprite is visible within a view ?

« on: February 17, 2017, 11:30:07 am »

Hi all,
I am a beginner with SFML and have a question.

Let's say I have a game with a scrollable view.

Is there a simple way using SFML to check if a given sprite (eg : an enemy) is visible within a view ? By visible I mean the sprite can be seen with the current scroll values, not that it is occluded by another sprite.

I have same problem with mouse : how to check that a the mouse cursor is inside a view ?