From 7f7d97f536ebbf5aa2e9335da728aa2056710297 Mon Sep 17 00:00:00 2001
From: Aaron Franke <arnfranke@yahoo.com>
Date: Tue, 31 Jul 2018 18:34:20 -0500
Subject: [PATCH] [Core] Expose approximate equality methods to GDScript

---
 doc/classes/@GDScript.xml               | 20 ++++++++++++++++++++
 modules/gdscript/gdscript_functions.cpp | 23 +++++++++++++++++++++++
 modules/gdscript/gdscript_functions.h   |  2 ++
 3 files changed, 45 insertions(+)

diff --git a/doc/classes/@GDScript.xml b/doc/classes/@GDScript.xml
index 29bf9b62ce9..22834a4c81e 100644
--- a/doc/classes/@GDScript.xml
+++ b/doc/classes/@GDScript.xml
@@ -498,6 +498,17 @@
 				[/codeblock]
 			</description>
 		</method>
+		<method name="is_equal_approx">
+			<return type="bool">
+			</return>
+			<argument index="0" name="a" type="float">
+			</argument>
+			<argument index="1" name="b" type="float">
+			</argument>
+			<description>
+				Returns True/False whether [code]a[/code] and [code]b[/code] are approximately equal to each other.
+			</description>
+		</method>
 		<method name="is_inf">
 			<return type="bool">
 			</return>
@@ -525,6 +536,15 @@
 				Returns whether [code]s[/code] is a NaN (Not-A-Number) value.
 			</description>
 		</method>
+		<method name="is_zero_approx">
+			<return type="bool">
+			</return>
+			<argument index="0" name="s" type="float">
+			</argument>
+			<description>
+				Returns True/False whether [code]s[/code] is zero or almost zero.
+			</description>
+		</method>
 		<method name="len">
 			<return type="int">
 			</return>
diff --git a/modules/gdscript/gdscript_functions.cpp b/modules/gdscript/gdscript_functions.cpp
index 4fd136d5cc1..7552bc6bffb 100644
--- a/modules/gdscript/gdscript_functions.cpp
+++ b/modules/gdscript/gdscript_functions.cpp
@@ -68,6 +68,8 @@ const char *GDScriptFunctions::get_func_name(Function p_func) {
 		"exp",
 		"is_nan",
 		"is_inf",
+		"is_equal_approx",
+		"is_zero_approx",
 		"ease",
 		"decimals",
 		"stepify",
@@ -316,6 +318,17 @@ void GDScriptFunctions::call(Function p_func, const Variant **p_args, int p_arg_
 			VALIDATE_ARG_NUM(0);
 			r_ret = Math::is_inf((double)*p_args[0]);
 		} break;
+		case MATH_ISEQUALAPPROX: {
+			VALIDATE_ARG_COUNT(2);
+			VALIDATE_ARG_NUM(0);
+			VALIDATE_ARG_NUM(1);
+			r_ret = Math::is_equal_approx((real_t)*p_args[0], (real_t)*p_args[1]);
+		} break;
+		case MATH_ISZEROAPPROX: {
+			VALIDATE_ARG_COUNT(1);
+			VALIDATE_ARG_NUM(0);
+			r_ret = Math::is_zero_approx((real_t)*p_args[0]);
+		} break;
 		case MATH_EASE: {
 			VALIDATE_ARG_COUNT(2);
 			VALIDATE_ARG_NUM(0);
@@ -1596,6 +1609,16 @@ MethodInfo GDScriptFunctions::get_info(Function p_func) {
 			mi.return_val.type = Variant::BOOL;
 			return mi;
 		} break;
+		case MATH_ISEQUALAPPROX: {
+			MethodInfo mi("is_equal_approx", PropertyInfo(Variant::REAL, "a"), PropertyInfo(Variant::REAL, "b"));
+			mi.return_val.type = Variant::BOOL;
+			return mi;
+		} break;
+		case MATH_ISZEROAPPROX: {
+			MethodInfo mi("is_zero_approx", PropertyInfo(Variant::REAL, "s"));
+			mi.return_val.type = Variant::BOOL;
+			return mi;
+		} break;
 		case MATH_EASE: {
 			MethodInfo mi("ease", PropertyInfo(Variant::REAL, "s"), PropertyInfo(Variant::REAL, "curve"));
 			mi.return_val.type = Variant::REAL;
diff --git a/modules/gdscript/gdscript_functions.h b/modules/gdscript/gdscript_functions.h
index 14bf3d75609..0dbd172acf2 100644
--- a/modules/gdscript/gdscript_functions.h
+++ b/modules/gdscript/gdscript_functions.h
@@ -59,6 +59,8 @@ public:
 		MATH_EXP,
 		MATH_ISNAN,
 		MATH_ISINF,
+		MATH_ISEQUALAPPROX,
+		MATH_ISZEROAPPROX,
 		MATH_EASE,
 		MATH_DECIMALS,
 		MATH_STEPIFY,