XNa game development (II) -- isfixedtimestep

[Original] Alex
By default, the update method is called 60 times per second, or updated every 16.667 milliseconds. You can change the update frequency by changing the targetelapsedtime variable: This. targetelapsedtime = timespan. fromseconds (1.0f/15000000f); when this line is calledCodeXNa calls the update method at 1500 times per second.

XNa does not call the update method at a fixed interval. To do this, set the is fixedtimestep variable to false.

 

 

Code

Using System;
Using System. Collections. Generic;
Using System. LINQ;
Using Microsoft. xNa. Framework;
Using Microsoft. xNa. Framework. Audio;
Using Microsoft. xNa. Framework. content;
Using Microsoft. xNa. Framework. gamerservices;
Using Microsoft. xNa. Framework. graphics;
Using Microsoft. xNa. Framework. input;
Using Microsoft. xNa. Framework. Media;
Using Microsoft. xNa. Framework. net;
Using Microsoft. xNa. Framework. storage;

Namespace Alex
{
///   <Summary>
/// This is the main type for your game
///   </Summary>
Public   Class Alexgame: Microsoft. xNa. Framework. Game
{
Graphicsdevicemanager graphics;
Spritebatch;
Int Updatecount =   0 ;
Public Alexgame ()
{
Graphics =   New Graphicsdevicemanager ( This );
Content. rootdirectory =   " Content " ;
}

///   <Summary>
/// Allows the game to perform any initialization it needs to before starting to run.
/// This is where it can query for any required services and load any non-graphic
/// Related content. Calling base. initialize will enumerate through any components
/// And initialize them as well.
///   </Summary>
Protected   Override   Void Initialize ()
{
// Todo: add your initialization logic here
// Set the number of refresh times
This . Targetelapsedtime = Timespan. fromseconds ( 1.0f   /   1500366f );
// The number of refresh attempts that call this method is invalid.
This . Isfixedtimestep =   False ;
Base . Initialize ();
}

///   <Summary>
/// Loadcontent will be called once per game and is the place to load
/// All of your content.
///   </Summary>
Protected   Override   Void Loadcontent ()
{
// Create a new spritebatch, which can be used to draw textures.
Spritebatch =   New Spritebatch (graphicsdevice );

//Todo: Use this. content to load your game content here
}

///   <Summary>
/// Unloadcontent will be called once per game and is the place to unload
/// All content.
///   </Summary>
Protected   Override   Void Unloadcontent ()
{
// Todo: unload any non contentmanager content here
}

///   <Summary>
/// Allows the game to run logic such as updating the world,
/// Checking for collisions, gathering input, and playing audio.
///   </Summary>
///   <Param name = "gametime"> Provides a snapshot of timing values. </Param>
Protected   Override   Void Update (gametime)
{
// Allows the game to exit
If (Gamepad. getstate (playerindex. One). Buttons. Back = Buttonstate. Pressed)
{
This . Exit ();
}
If (Keyboard. getstate (). iskeydown (Keys. Escape ))
{
This . Exit ();
}
Updatecount = Updatecount + 1 ;
This . Window. Title = Updatecount. tostring ();

//Todo: add your update logic here

Base. Update (gametime );
}

///   <Summary>
/// This is called when the game shoshould draw itself.
///   </Summary>
///   <Param name = "gametime"> Provides a snapshot of timing values. </Param>
Protected   Override   Void Draw (gametime)
{
Graphicsdevice. Clear (color. cornflowerblue );

//Todo: add your drawing code here

Base. Draw (gametime );
}
}
}Running result: