godot/doc/classes/float.xml
Hugo Locurcio 063637ec77
Rename float=64 SCons option to precision=double
This avoids confusion with the old `bits=64` option and building
for 64-bit CPUs in general.
2022-12-10 16:43:45 +01:00

298 lines
11 KiB
XML

<?xml version="1.0" encoding="UTF-8" ?>
<class name="float" version="4.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../class.xsd">
<brief_description>
Float built-in type.
</brief_description>
<description>
The [float] built-in type is a 64-bit double-precision floating-point number, equivalent to [code]double[/code] in C++. This type has 14 reliable decimal digits of precision. The [float] type can be stored in [Variant], which is the generic type used by the engine. The maximum value of [float] is approximately [code]1.79769e308[/code], and the minimum is approximately [code]-1.79769e308[/code].
Many methods and properties in the engine use 32-bit single-precision floating-point numbers instead, equivalent to [code]float[/code] in C++, which have 6 reliable decimal digits of precision. For data structures such as [Vector2] and [Vector3], Godot uses 32-bit floating-point numbers by default, but it can be changed to use 64-bit doubles if Godot is compiled with the [code]precision=double[/code] option.
Math done using the [float] type is not guaranteed to be exact or deterministic, and will often result in small errors. You should usually use the [method @GlobalScope.is_equal_approx] and [method @GlobalScope.is_zero_approx] methods instead of [code]==[/code] to compare [float] values for equality.
</description>
<tutorials>
<link title="Wikipedia: Double-precision floating-point format">https://en.wikipedia.org/wiki/Double-precision_floating-point_format</link>
<link title="Wikipedia: Single-precision floating-point format">https://en.wikipedia.org/wiki/Single-precision_floating-point_format</link>
</tutorials>
<constructors>
<constructor name="float">
<return type="float" />
<description>
Constructs a default-initialized [float] set to [code]0.0[/code].
</description>
</constructor>
<constructor name="float">
<return type="float" />
<param index="0" name="from" type="float" />
<description>
Constructs a [float] as a copy of the given [float].
</description>
</constructor>
<constructor name="float">
<return type="float" />
<param index="0" name="from" type="String" />
<description>
Converts a [String] to a [float], following the same rules as [method String.to_float].
</description>
</constructor>
<constructor name="float">
<return type="float" />
<param index="0" name="from" type="bool" />
<description>
Cast a [bool] value to a floating-point value, [code]float(true)[/code] will be equal to 1.0 and [code]float(false)[/code] will be equal to 0.0.
</description>
</constructor>
<constructor name="float">
<return type="float" />
<param index="0" name="from" type="int" />
<description>
Cast an [int] value to a floating-point value, [code]float(1)[/code] will be equal to [code]1.0[/code].
</description>
</constructor>
</constructors>
<operators>
<operator name="operator !=">
<return type="bool" />
<param index="0" name="right" type="float" />
<description>
Returns [code]true[/code] if two floats are different from each other.
</description>
</operator>
<operator name="operator !=">
<return type="bool" />
<param index="0" name="right" type="int" />
<description>
Returns [code]true[/code] if the integer has different value than the float.
</description>
</operator>
<operator name="operator *">
<return type="Color" />
<param index="0" name="right" type="Color" />
<description>
Multiplies each component of the [Color] by the given [float].
[codeblock]
print(1.5 * Color(0.5, 0.5, 0.5)) # Color(0.75, 0.75, 0.75)
[/codeblock]
</description>
</operator>
<operator name="operator *">
<return type="Quaternion" />
<param index="0" name="right" type="Quaternion" />
<description>
Multiplies each component of the [Quaternion] by the given [float]. This operation is not meaningful on its own, but it can be used as a part of a larger expression.
</description>
</operator>
<operator name="operator *">
<return type="Vector2" />
<param index="0" name="right" type="Vector2" />
<description>
Multiplies each component of the [Vector2] by the given [float].
[codeblock]
print(2.5 * Vector2(1, 3)) # Prints "(2.5, 7.5)"
[/codeblock]
</description>
</operator>
<operator name="operator *">
<return type="Vector2" />
<param index="0" name="right" type="Vector2i" />
<description>
Multiplies each component of the [Vector2i] by the given [float]. Returns a [Vector2].
[codeblock]
print(0.9 * Vector2i(10, 15)) # Prints "(9, 13.5)"
[/codeblock]
</description>
</operator>
<operator name="operator *">
<return type="Vector3" />
<param index="0" name="right" type="Vector3" />
<description>
Multiplies each component of the [Vector3] by the given [float].
</description>
</operator>
<operator name="operator *">
<return type="Vector3" />
<param index="0" name="right" type="Vector3i" />
<description>
Multiplies each component of the [Vector3i] by the given [float]. Returns a [Vector3].
[codeblock]
print(0.9 * Vector3i(10, 15, 20)) # Prints "(9, 13.5, 18)"
[/codeblock]
</description>
</operator>
<operator name="operator *">
<return type="Vector4" />
<param index="0" name="right" type="Vector4" />
<description>
Multiplies each component of the [Vector4] by the given [float].
</description>
</operator>
<operator name="operator *">
<return type="Vector4" />
<param index="0" name="right" type="Vector4i" />
<description>
Multiplies each component of the [Vector4i] by the given [float]. Returns a [Vector4].
[codeblock]
print(0.9 * Vector4i(10, 15, 20, -10)) # Prints "(9, 13.5, 18, -9)"
[/codeblock]
</description>
</operator>
<operator name="operator *">
<return type="float" />
<param index="0" name="right" type="float" />
<description>
Multiplies two [float]s.
</description>
</operator>
<operator name="operator *">
<return type="float" />
<param index="0" name="right" type="int" />
<description>
Multiplies a [float] and an [int]. The result is a [float].
</description>
</operator>
<operator name="operator **">
<return type="float" />
<param index="0" name="right" type="float" />
<description>
Raises a [float] to a power of a [float].
[codeblock]
print(39.0625**0.25) # 2.5
[/codeblock]
</description>
</operator>
<operator name="operator **">
<return type="float" />
<param index="0" name="right" type="int" />
<description>
Raises a [float] to a power of an [int]. The result is a [float].
[codeblock]
print(0.9**3) # 0.729
[/codeblock]
</description>
</operator>
<operator name="operator +">
<return type="float" />
<param index="0" name="right" type="float" />
<description>
Adds two floats.
</description>
</operator>
<operator name="operator +">
<return type="float" />
<param index="0" name="right" type="int" />
<description>
Adds a [float] and an [int]. The result is a [float].
</description>
</operator>
<operator name="operator -">
<return type="float" />
<param index="0" name="right" type="float" />
<description>
Subtracts a float from a float.
</description>
</operator>
<operator name="operator -">
<return type="float" />
<param index="0" name="right" type="int" />
<description>
Subtracts an [int] from a [float]. The result is a [float].
</description>
</operator>
<operator name="operator /">
<return type="float" />
<param index="0" name="right" type="float" />
<description>
Divides two floats.
</description>
</operator>
<operator name="operator /">
<return type="float" />
<param index="0" name="right" type="int" />
<description>
Divides a [float] by an [int]. The result is a [float].
</description>
</operator>
<operator name="operator &lt;">
<return type="bool" />
<param index="0" name="right" type="float" />
<description>
Returns [code]true[/code] if the left float is less than the right one.
</description>
</operator>
<operator name="operator &lt;">
<return type="bool" />
<param index="0" name="right" type="int" />
<description>
Returns [code]true[/code] if this [float] is less than the given [int].
</description>
</operator>
<operator name="operator &lt;=">
<return type="bool" />
<param index="0" name="right" type="float" />
<description>
Returns [code]true[/code] if the left float is less than or equal to the right one.
</description>
</operator>
<operator name="operator &lt;=">
<return type="bool" />
<param index="0" name="right" type="int" />
<description>
Returns [code]true[/code] if this [float] is less than or equal to the given [int].
</description>
</operator>
<operator name="operator ==">
<return type="bool" />
<param index="0" name="right" type="float" />
<description>
Returns [code]true[/code] if both floats are exactly equal.
[b]Note:[/b] Due to floating-point precision errors, consider using [method @GlobalScope.is_equal_approx] or [method @GlobalScope.is_zero_approx] instead, which are more reliable.
</description>
</operator>
<operator name="operator ==">
<return type="bool" />
<param index="0" name="right" type="int" />
<description>
Returns [code]true[/code] if the [float] and the given [int] are equal.
</description>
</operator>
<operator name="operator &gt;">
<return type="bool" />
<param index="0" name="right" type="float" />
<description>
Returns [code]true[/code] if the left float is greater than the right one.
</description>
</operator>
<operator name="operator &gt;">
<return type="bool" />
<param index="0" name="right" type="int" />
<description>
Returns [code]true[/code] if this [float] is greater than the given [int].
</description>
</operator>
<operator name="operator &gt;=">
<return type="bool" />
<param index="0" name="right" type="float" />
<description>
Returns [code]true[/code] if the left float is greater than or equal to the right one.
</description>
</operator>
<operator name="operator &gt;=">
<return type="bool" />
<param index="0" name="right" type="int" />
<description>
Returns [code]true[/code] if this [float] is greater than or equal to the given [int].
</description>
</operator>
<operator name="operator unary+">
<return type="float" />
<description>
Returns the same value as if the [code]+[/code] was not there. Unary [code]+[/code] does nothing, but sometimes it can make your code more readable.
</description>
</operator>
<operator name="operator unary-">
<return type="float" />
<description>
Returns the negative value of the [float]. If positive, turns the number negative. If negative, turns the number positive. With floats, the number zero can be either positive or negative.
</description>
</operator>
</operators>
</class>