11 Writing Text Session 5.1

Session Overview  Show how fonts are managed in computers  Discover the difference between bitmap fonts and vector fonts  Find out how to create font resources in an XNA program  Add a font to a game and use it to display text messages  Discover how font properties are managed and how to create different text sizes  Show how fonts are managed in computers  Discover the difference between bitmap fonts and vector fonts  Find out how to create font resources in an XNA program  Add a font to a game and use it to display text messages  Discover how font properties are managed and how to create different text sizes Chapter 5.1: Writing Text2

Text and Computers  Early computers did not print text at all  Output was displayed by lights, or punched on paper tape  Later devices were restricted to the physical design of mechanical print heads and characters built into text displays  Only recently have computers become powerful enough to be able to manage the range of fonts and type sizes that are taken for granted today  Early computers did not print text at all  Output was displayed by lights, or punched on paper tape  Later devices were restricted to the physical design of mechanical print heads and characters built into text displays  Only recently have computers become powerful enough to be able to manage the range of fonts and type sizes that are taken for granted today Chapter 5.1: Writing Text3

Fonts  A font is a set of character designs in a particular style  There are many different font designs  Popular ones are: Arial Times New Roman Courier  A font is a set of character designs in a particular style  There are many different font designs  Popular ones are: Arial Times New Roman Courier Chapter 5.1: Writing Text4

Bitmap Fonts  In the early days of computers the font was actually a set of images, one for each character, drawn at a particular size  These bitmapped fonts were hard to scale so a font design had to be supplied in a range of sizes  In the early days of computers the font was actually a set of images, one for each character, drawn at a particular size  These bitmapped fonts were hard to scale so a font design had to be supplied in a range of sizes Chapter 5.1: Writing Text5

Vector Fonts  Characters in a vector font are created by joining dots with lines  The computer uses an equation to work out the position of each point on the character shape  This makes scaling very easy, but makes a lot of work for the computer  Characters in a vector font are created by joining dots with lines  The computer uses an equation to work out the position of each point on the character shape  This makes scaling very easy, but makes a lot of work for the computer Chapter 5.1: Writing Text6

Fonts in XNA  A font in an XNA program is an item of content  It is a bitmap font which is rendered at a particular size and then drawn as a sprite  This is so XNA games can draw text as quickly as possible  The Content Manager generates the SpriteFont resource from a Windows PC font when the program is built  This is all done automatically  A font in an XNA program is an item of content  It is a bitmap font which is rendered at a particular size and then drawn as a sprite  This is so XNA games can draw text as quickly as possible  The Content Manager generates the SpriteFont resource from a Windows PC font when the program is built  This is all done automatically Chapter 5.1: Writing Text7

Adding a Font Resource  A font resource is added in a similar way to an image  The difference is that we need to create a new item, rather than load an existing picture  This opens the “Add New Item – Content” dialog  A font resource is added in a similar way to an image  The difference is that we need to create a new item, rather than load an existing picture  This opens the “Add New Item – Content” dialog Chapter 5.1: Writing Text8

Creating a New SpriteFont  The Add New Item dialog lets you select the content you want to add  For a font select SpriteFont and click Add  The Add New Item dialog lets you select the content you want to add  For a font select SpriteFont and click Add Chapter 5.1: Writing Text9

The Added Font Resource  Once the font has been added it appears in the Content part of the solution  You can add multiple fonts if a game needs to have different sizes or styles of text  The XNA Content Manager takes care of all this automatically  Once the font has been added it appears in the Content part of the solution  You can add multiple fonts if a game needs to have different sizes or styles of text  The XNA Content Manager takes care of all this automatically Chapter 5.1: Writing Text10

Building a SpriteFont  When a game program is built, the Content Manager performs the following sequence: 1. It looks in the font resource file to find out what font to use and what sized characters are required. 2. It uses this font on the Windows PC to generate a set of bitmaps (the actual SpriteFont) and puts this into a file. 3. It copies the SpriteFont file it has produced into the right place for the game to use when it runs.  When a game program is built, the Content Manager performs the following sequence: 1. It looks in the font resource file to find out what font to use and what sized characters are required. 2. It uses this font on the Windows PC to generate a set of bitmaps (the actual SpriteFont) and puts this into a file. 3. It copies the SpriteFont file it has produced into the right place for the game to use when it runs. Chapter 5.1: Writing Text11

Configuring a SpriteFont  The font and size settings for a SpriteFont are held in the SpriteFont file  You can open this file and edit it within Microsoft Visual Studio  The file itself is held in the XML file format  The font and size settings for a SpriteFont are held in the SpriteFont file  You can open this file and edit it within Microsoft Visual Studio  The file itself is held in the XML file format Chapter 5.1: Writing Text12

What Is XML?  XML stands for “eXtensible Markup Language”  It means “Way I can put stuff into a file that you (and a computer) can understand”  It is a format that lets you give data a structure  Above I’ve created an XML file to hold high score information  XML stands for “eXtensible Markup Language”  It means “Way I can put stuff into a file that you (and a computer) can understand”  It is a format that lets you give data a structure  Above I’ve created an XML file to hold high score information Chapter 5.1: Writing Text13 Rob Miles 1500

SpriteFont XML  There are numerous font properties that you might want to change  These are the two most important ones  There are numerous font properties that you might want to change  These are the two most important ones Chapter 5.1: Writing Text14 <!— Modify this string to change the font that will be imported. --> Kootenay <!— Size is a float value, measured in points. Modify this value to change the size of the font. --> 14 <!— Modify this string to change the font that will be imported. --> Kootenay <!— Size is a float value, measured in points. Modify this value to change the size of the font. --> 14

Editing a SpriteFont Chapter 5.1: Writing Text15

Adding a SpriteFont value to the Game World  If a game needs to display text messages it needs a SpriteFont variable as part of the game world  This will be used when the characters are drawn  A SpriteFont is a bit like a Texture2D, except that it contains a set of character designs rather than a single image  It will be used with the SpriteBatch to draw text  If a game needs to display text messages it needs a SpriteFont variable as part of the game world  This will be used when the characters are drawn  A SpriteFont is a bit like a Texture2D, except that it contains a set of character designs rather than a single image  It will be used with the SpriteBatch to draw text Chapter 5.1: Writing Text16 // Game World SpriteFont font; // Game World SpriteFont font;

Loading a SpriteFont  The best place to load a SpriteFont is in the LoadContent method  The format of the load is similar to image loading  This time we ask the Load method to fetch a SpriteFont rather than a Texture2D  The best place to load a SpriteFont is in the LoadContent method  The format of the load is similar to image loading  This time we ask the Load method to fetch a SpriteFont rather than a Texture2D Chapter 5.1: Writing Text17 protected override void LoadContent() { // Create a new SpriteBatch spriteBatch = new SpriteBatch(GraphicsDevice); font = Content.Load ("SpriteFont1"); }

Drawing Text with the DrawString Method  The SpriteBatch type provides a method called DrawString which draws a string of text on the display  DrawString is told:  the font to use to draw the text  the string of text to draw  the vector identifying the position on the display to start drawing  the color to draw the text with  The SpriteBatch type provides a method called DrawString which draws a string of text on the display  DrawString is told:  the font to use to draw the text  the string of text to draw  the vector identifying the position on the display to start drawing  the color to draw the text with Chapter 5.1: Writing Text18

Vectors  A vector is a way of packaging together values that describe a particular position relative to the origin  They can be 2D (x,y) or 3D (x,y,z)  They can also be used to describe a direction  We need to create a 2D vector to position the text  The XNA type for a 2D vector is called Vector2  The above statements create a vector set to 20,30  A vector is a way of packaging together values that describe a particular position relative to the origin  They can be 2D (x,y) or 3D (x,y,z)  They can also be used to describe a direction  We need to create a 2D vector to position the text  The XNA type for a 2D vector is called Vector2  The above statements create a vector set to 20,30 Chapter 5.1: Writing Text19 Vector2 textVector = new Vector2(20, 30 );

Drawing Hello World Chapter 5.1: Writing Text20 protected override void Draw(GameTime gameTime) { graphics.GraphicsDevice.Clear(Color.CornflowerBlue); Vector2 textVector = new Vector2(20, 30 ); spriteBatch.Begin(); spriteBatch.DrawString(font, "Hello World", textVector, Color.Red); spriteBatch.End(); base.Draw(gameTime); } protected override void Draw(GameTime gameTime) { graphics.GraphicsDevice.Clear(Color.CornflowerBlue); Vector2 textVector = new Vector2(20, 30 ); spriteBatch.Begin(); spriteBatch.DrawString(font, "Hello World", textVector, Color.Red); spriteBatch.End(); base.Draw(gameTime); }

1. Drawing Text Chapter 5.1: Writing Text21  Visual Studio creates and manages a number of folders which all hold parts of the game project  This includes a folder that contains the content for the game  Visual Studio creates and manages a number of folders which all hold parts of the game project  This includes a folder that contains the content for the game

Summary  Computers can manage character fonts as either bitmaps (an image that holds a picture of the character) or vectors (a set of lines and points that describe how to draw a character)  XNA regards a font as a set of bitmaps that have been produced by the Content Manager from a vector font when the program is built  XNA font properties are held in XML  Fonts are loaded and used by a game in a very similar way to textures  Computers can manage character fonts as either bitmaps (an image that holds a picture of the character) or vectors (a set of lines and points that describe how to draw a character)  XNA regards a font as a set of bitmaps that have been produced by the Content Manager from a vector font when the program is built  XNA font properties are held in XML  Fonts are loaded and used by a game in a very similar way to textures Chapter 5.1: Writing Text22

True/False Revision Quiz  Bitmap fonts are the slowest type of font to draw.  An XNA game can only contain one font.  A vector font describes how to draw the characters.  XML is only used for SpriteFont files.  The XNA Content Manager draws the fonts on the display.  Bitmap fonts are the slowest type of font to draw.  An XNA game can only contain one font.  A vector font describes how to draw the characters.  XML is only used for SpriteFont files.  The XNA Content Manager draws the fonts on the display. Chapter 5.1: Writing Text23

True/False Revision Quiz  Bitmap fonts are the slowest type of font to draw.  An XNA game can only contain one font.  A vector font describes how to draw the characters.  XML is only used for SpriteFont files.  The XNA Content Manager draws the fonts on the display.  Bitmap fonts are the slowest type of font to draw.  An XNA game can only contain one font.  A vector font describes how to draw the characters.  XML is only used for SpriteFont files.  The XNA Content Manager draws the fonts on the display. Chapter 5.1: Writing Text24

True/False Revision Quiz  Bitmap fonts are the slowest type of font to draw.  An XNA game can only contain one font.  A vector font describes how to draw the characters.  XML is only used for SpriteFont files.  The XNA Content Manager draws the text on the display.  Bitmap fonts are the slowest type of font to draw.  An XNA game can only contain one font.  A vector font describes how to draw the characters.  XML is only used for SpriteFont files.  The XNA Content Manager draws the text on the display. Chapter 5.1: Writing Text25

True/False Revision Quiz  Bitmap fonts are the slowest type of font to draw.  An XNA game can only contain one font.  A vector font describes how to draw the characters.  XML is only used for SpriteFont files.  The XNA Content Manager draws the text on the display.  Bitmap fonts are the slowest type of font to draw.  An XNA game can only contain one font.  A vector font describes how to draw the characters.  XML is only used for SpriteFont files.  The XNA Content Manager draws the text on the display. Chapter 5.1: Writing Text26

True/False Revision Quiz  Bitmap fonts are the slowest type of font to draw.  An XNA game can only contain one font.  A vector font describes how to draw the characters.  XML is only used for SpriteFont files.  The XNA Content Manager draws the text on the display.  Bitmap fonts are the slowest type of font to draw.  An XNA game can only contain one font.  A vector font describes how to draw the characters.  XML is only used for SpriteFont files.  The XNA Content Manager draws the text on the display. Chapter 5.1: Writing Text27

True/False Revision Quiz  Bitmap fonts are the slowest type of font to draw.  An XNA game can only contain one font.  A vector font describes how to draw the characters.  XML is only used for SpriteFont files.  The XNA Content Manager draws the text on the display.  Bitmap fonts are the slowest type of font to draw.  An XNA game can only contain one font.  A vector font describes how to draw the characters.  XML is only used for SpriteFont files.  The XNA Content Manager draws the text on the display. Chapter 5.1: Writing Text28