extend(vec) and extend_bound(bound) for bounds

expands bounds to cover new points

modules/bound2.lua

@@ -62,6 +62,22 @@ function bound2.at(a, b) -- "bounded by". b may be nil
 	end
 end
 
+--- Extend bound to include point
+-- @tparam bound2 a bound
+-- @tparam vec2 point to include
+-- @treturn bound2 Bound covering current min, current max and new point
+function bound2.extend(a, center)
+	return bound2.new(a.min:component_min(center), a.max:component_max(center))
+end
+
+--- Extend bound to entirety of other bound
+-- @tparam bound2 a bound
+-- @tparam bound2 bound to cover
+-- @treturn bound2 Bound covering current min and max of each bound in the pair
+function bound2.extend_bound(a, b)
+	return a:extend(b.min):extend(b.max)
+end
+
 --- Get size of bounding box as a vector 
 -- @tparam bound2 a bound
 -- @treturn vec2 Vector spanning min to max points

modules/bound3.lua

@@ -62,6 +62,22 @@ function bound3.at(a, b) -- "bounded by". b may be nil
 	end
 end
 
+--- Extend bound to include point
+-- @tparam bound3 a bound
+-- @tparam vec3 point to include
+-- @treturn bound3 Bound covering current min, current max and new point
+function bound3.extend(a, center)
+	return bound3.new(a.min:component_min(center), a.max:component_max(center))
+end
+
+--- Extend bound to entirety of other bound
+-- @tparam bound3 a bound
+-- @tparam bound3 bound to cover
+-- @treturn bound3 Bound covering current min and max of each bound in the pair
+function bound3.extend_bound(a, b)
+	return a:extend(b.min):extend(b.max)
+end
+
 --- Get size of bounding box as a vector 
 -- @tparam bound3 a bound
 -- @treturn vec3 Vector spanning min to max points

spec/bound2_spec.lua

@@ -171,6 +171,42 @@ describe("bound2:", function()
 		assert.is_not_true(a:contains(vec2(2,3)))
 	end)
 
+	it("extends a bound2 with a point", function()
+		local min = vec2(1,2)
+		local max = vec2(4,5)
+		local downright = vec2(8,8)
+		local downleft = vec2(-4,8)
+		local top = vec2(2, 0)
+
+		local a = bound2(min, max)
+		local temp
+
+		temp = a:extend(downright)
+		assert.is_true(a.min == min and a.max == max)
+		assert.is_true(temp.min == min and temp.max == downright)
+		temp = a:extend(downleft)
+		assert.is_true(temp.min == vec2(-4,2) and temp.max == vec2(4,8))
+		temp = a:extend(top)
+		assert.is_true(temp.min == vec2(1,0) and temp.max == max)
+	end)
+
+	it("extends a bound with another bound", function()
+		local min = vec2(1,2)
+		local max = vec2(4,5)
+		local leftexpand = bound2.new(vec2(0,0), vec2(1.5, 6))
+		local rightexpand = bound2.new(vec2(1.5,0), vec2(5, 6))
+
+		local a = bound2(min, max)
+		local temp
+
+		temp = a:extend_bound(leftexpand)
+		assert.is_equal(temp.min, vec2(0,0))
+		assert.is_equal(temp.max, vec2(4,6))
+		temp = temp:extend_bound(rightexpand)
+		assert.is_equal(temp.min, vec2(0,0))
+		assert.is_equal(temp.max, vec2(5,6))
+	end)
+	
 	it("checks for bound2.zero", function()
 		assert.is.equal(0, bound2.zero.min.x)
 		assert.is.equal(0, bound2.zero.min.y)

spec/bound3_spec.lua

@@ -208,6 +208,42 @@ describe("bound3:", function()
 		assert.is_not_true(a:contains(vec3(2,3,7)))
 	end)
 
+	it("extends a bound3 with a point", function()
+		local min = vec3(1,2,6)
+		local max = vec3(4,5,9)
+		local downright = vec3(8,8,10)
+		local downleft = vec3(-4,8,10)
+		local top = vec3(2, 0, 7)
+
+		local a = bound3(min, max)
+		local temp
+
+		temp = a:extend(downright)
+		assert.is_true(a.min == min and a.max == max)
+		assert.is_true(temp.min == min and temp.max == downright)
+		temp = a:extend(downleft)
+		assert.is_true(temp.min == vec3(-4,2,6) and temp.max == vec3(4,8,10))
+		temp = a:extend(top)
+		assert.is_true(temp.min == vec3(1,0,6) and temp.max == max)
+	end)
+
+	it("extends a bound with another bound", function()
+		local min = vec3(1,2,3)
+		local max = vec3(4,5,6)
+		local leftexpand = bound3.new(vec3(0,0,4), vec3(1.5,6,5))
+		local rightexpand = bound3.new(vec3(1.5,0,1), vec3(5,6,7))
+
+		local a = bound3(min, max)
+		local temp
+
+		temp = a:extend_bound(leftexpand)
+		assert.is_equal(temp.min, vec3(0,0,3))
+		assert.is_equal(temp.max, vec3(4,6,6))
+		temp = temp:extend_bound(rightexpand)
+		assert.is_equal(temp.min, vec3(0,0,1))
+		assert.is_equal(temp.max, vec3(5,6,7))
+	end)
+
 	it("checks for bound3.zero", function()
 		assert.is.equal(0, bound3.zero.min.x)
 		assert.is.equal(0, bound3.zero.min.y)