Torque2D MIT 学习笔记(4) ---- 脚本语法(2)

数字

TorqueScript支持的数字类型有四种:

123        // 整型
1.23       // 浮点
123e-4  // 科学计数
0xabcd  // 十六进制
 

字符串

文本,比如名字或者短语词组都可以作为字符串存储.

数字也可以以字符串格式存储.

标准的字符串存储在双引号标记区域内.如:

"123abc"

标记字符串存储在单引号标记区域内,如:

'123abc'

在TorqueScript中,标记字符串会被特殊对待,他们不仅有自己的字符串数据还有一个与之相关联的特殊数字标记.

标记字符串通常被用在网络数据发送中,不管实际发送多少次字符串,其字符串数据只会被发送一次,其他的时间都是发送标记值.

在使用的时候需要通过detag命令来解析内容,通常我们用不到标记字符串,除非有很多字符串要通过网络传递,比如聊天系统等等.如下:

$a = 'This is a tagged string';
echo("  Tagged string: ", $a);
echo("Detagged string: ", detag('$a'));

输出结果为:

   Tagged string:
SOH1
Detagged string:

第二行为空值,除非字符串是通过网络传递到客户端的.

 

字符串运算符

基本语法: "string1" operation "string2"

如同使用数学运算符一样,TorqueScript提供了四种操作符供程序猿使用.

@     连接两个字符串
TAB   使用制表符连接两个字符串
SPC   使用空格连接两个字符串
NL    新行

比如:

echo("Hello" @ "World");
echo("Hello" TAB "World");
echo("Hello" SPC "World");
echo("Hello" NL "World");

OUTPUT:
HelloWorld
Hello   World
Hello World
Hello
World

布尔型

true (1)

false (0)

和其他许多编程语言一样,0和false被认为假,true和非零被认为真,常常被用来作为条件判断的开关,如下:

$lightsOn = true;

if($lightsOn)
  echo("Lights are turned on");

数组

数组结构被用来存储连贯的相同类型的数据,比如:

$TestArray[n]   (一维数组)
$TestArray[m,n] (二维数组)
$TestArray[m_n] (二维数组)

PS:数组下标从0开始.

比如:

$userNames[0] = "Heather";
$userNames[1] = "Nikki";
$userNames[2] = "Mich";

echo($userNames[0]);
echo($userNames[1]);
echo($userNames[2]);

 

向量

在TorqueScript中"向量"(组合数据)是一种非常重要的类型,比如SceneObject就有许多的变量时2或3个数据的组合类型,比如位置,向量,颜色等.

一次性赋值的时候以字符串的方式,单个数据之间用空格分隔,比如:

%position = "25 32";
%firstColor = "100 100 100 1.0";
echo(%firstColor);

脚本变量的组合方式:

%red = 128;
%blue = 255;
%green = 64;
%alpha = 1.0;

%secondColor = %red SPC %blue SPC %green SPC %alpha;
echo(%secondColor);

 

运算符

算数运算符:

Operator	Name	Example	Explanation
*	multiplication	$a * $b	Multiply $a and $b.
/	division	$a / $b	Divide $a by $b.
%	modulo	$a % $b	Remainder of $a divided by $b.
+	addition	$a + $b	Add $a and $b.
-	subtraction	$a - $b	Subtract $b from $a.
++	auto-increment (post-fix only)	$a++	Increment $a. The value of $a++ is that of the incremented variable: auto-increment is post-fix in syntax, but pre-increment in sematics (the variable is incremented, before the return value is calculated). This behavior is unlike that of C and C++.
--	auto-decrement (post-fix only)	$b--	Decrement $b. The value of $a-- is that of the decremented variable: auto-decrement is post-fix in syntax, but pre-decrement in sematics (the variable is decremented, before the return value is calculated). This behavior is unlike that of C and C++.

 

关系运算符:

Operator	Name	Example	Explanation
`<	Less than	$a < $b	1 if $a is less than % b (0 otherwise.)
`>	More than	$a > $b	1 if $a is greater than % b (0 otherwise.)
`<=	Less than or Equal to	$a <= $b	1 if $a is less than or equal to % b (0 otherwise.)
`>=	More than or Equal to	$a >= $b	1 if $a is greater than or equal to % b (0 otherwise.)
`==	Equal to	$a == $b	1 if $a is equal to % b (0 otherwise.)
`!=	Not equal to	$a != $b	1 if $a is not equal to % b (0 otherwise.)
`!	Logical NOT	!$a	1 if $a is 0 (0 otherwise.)
`&&	Logical AND	$a && $b	1 if $a and $b are both non-zero (0 otherwise.)
$=	String equal to	$c $= $d	1 if $c equal to $d .
!$=	String not equal to	$c !$= $d	1 if $c not equal to $d.

还有一个额外的逻辑或操作, ||, 比如:

$a || $b

两者有一个非零,结果就为1,否则为0;

 

位操作

Operator	Name	Example	Explanation
~	Bitwise complement	~$a	flip bits 1 to 0 and 0 to 1. (i.e. ~10b == 01b)
&	Bitwise AND	$a & $b	composite of elements where bits in same position are 1. (i.e. 1b & 1b == 1b)
^	Bitwise XOR	$a ^ $b	composite of elements where bits in same position are opposite. (i.e. 100b & 101b == 001b)
<<	Left Shift	$a << 3	element shifted left by 3 and padded with zeros. (i.e. 11b << 3d == 11000b)
>>	Right Shift	$a >> 3	element shifted right by 3 and padded with zeros. (i.e. 11010b >> 3d == 00011b)

还有一个额外的位或操作, |, 比如:

$a | $b

赋值

Operator	Name	Example	Explanation
Assignment	$a = $b;	Assign value of $b to $a.	Note: the value of an assignment is the value being assigned, so $a = $b = $c is legal.
op=	Assignment Operators	$a op= $b;	Equivalent to $a = $a op $b, where op can be any of:
* / % + - &	^ << >>