From e6b9c84a6c45030b2704c0411e5f1576d56d4f36 Mon Sep 17 00:00:00 2001
From: Colby Klein <shakesoda@gmail.com>
Date: Sat, 15 Aug 2015 01:19:32 -0700
Subject: [PATCH] Add utils.deadzone and threshold + tests

---
 modules/utils.lua   |  9 +++++++++
 spec/utils_spec.lua | 23 ++++++++++++++++++++++-
 2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/modules/utils.lua b/modules/utils.lua
index 68494a3..683fac6 100644
--- a/modules/utils.lua
+++ b/modules/utils.lua
@@ -4,6 +4,15 @@ function utils.clamp(v, min, max)
 	return math.max(math.min(v, max), min)
 end
 
+function utils.deadzone(value, size)
+	return math.abs(value) >= size and value or 0
+end
+
+-- I know, it barely saves any typing at all.
+function utils.threshold(value, threshold)
+	return math.abs(value) >= threshold
+end
+
 function utils.map(v, min_in, max_in, min_out, max_out)
 	return ((v) - (min_in)) * ((max_out) - (min_out)) / ((max_in) - (min_in)) + (min_out)
 end
diff --git a/spec/utils_spec.lua b/spec/utils_spec.lua
index 846710d..dd68444 100644
--- a/spec/utils_spec.lua
+++ b/spec/utils_spec.lua
@@ -35,5 +35,26 @@ describe("utils:", function()
 		assert.is.is_true(math.abs(utils.round(5.5555, 0.1) - 5.6) < constants.FLT_EPSILON)
 	end)
 
-	pending "lerp"
+	it("testing deadzone", function()
+		assert.is.equal(utils.deadzone(0.5, 0.05), 0.5)
+		assert.is.equal(utils.deadzone(0.02, 0.05), 0.0)
+		assert.is.equal(utils.deadzone(-0.1, 0.02), -0.1)
+	end)
+
+	it("testing threshold", function()
+		assert.is_true(utils.threshold(0.5, 0.25))
+		assert.is_true(utils.threshold(0.25, 0.25))
+		assert.is_false(utils.threshold(-0.1, 0.5))
+		assert.is_true(utils.threshold(-0.25, 0.1))
+	end)
+
+	it("testing lerp", function()
+		local l = 0.5
+		local h = 20.0
+		assert.is.equal(utils.lerp(0, l, h), l)
+		assert.is.equal(utils.lerp(1, l, h), h)
+		assert.is.equal(utils.lerp(0.5, l, h), (l+h)/2)
+	end)
+
+	pending "smoothstep"
 end)