Rect2().encloses(Rect2()) with same rect is false

[AlexHolly]

Result is false, expected true
Rect2(0,0,1,1).encloses( Rect2(0,0,1,1) )
Rect2(0,0,0,0).encloses( Rect2(0,0,0,0) )

godot/core/math/rect2.h

Line 99 in b16c309

inline bool encloses(const Rect2 &p_rect) const {

Compared with java

import java.awt.Rectangle;

class Main {
  public static void main(String[] args) {
    System.out.println(new Rectangle(0,0,1,1).contains(new Rectangle(0,0,1,1))); // true
    System.out.println(new Rectangle(0,0,0,0).contains(new Rectangle(0,0,0,0))); // false
  }
}

I suggest simply do <= instead of <
https://github.com/godotengine/godot/blob/b16c309f82c77d606472c3c721a1857e323a09e7/core/math/rect2.h#L102-#L103

It will return true in this case which differs from Java but that should be fine.
Rect2(0,0,0,0).encloses( Rect2(0,0,0,0) )

[aaronfranke]

I suppose the question then would be "what is the desired functionality"? Should a rectangle enclose itself? What are the game programming use cases for true vs false?

See also: #25829 Might want to look over all this code at once.

[ghost]

if A is a Rect2 representing the game map area
and B is a Rect2 reprensenting the area of a building
then
A.encloses(B) should return true because the workaround is enlarging virtually the map (not really good) or shrinking virtually the futur building (probably by 0.1 map unit) => not very elegant but its what I do because of this bug

[akien-mga]

@xakz What's your use case for A.encloses(B) if A is the same size as B?

[ghost]

@akien-mga Probably none but:
Rect2(0, 0, 2, 2).encloses(Rect2(1, 1, 1, 1)) returns false
and
Rect2(0, 0, 2, 2).encloses(Rect2(1, 1, 0.99999, 0.99999)) returns true

For world coordinates, it's not really a problem, but for map coordinates (TileMap) it's not what one expect. We expect a 1x1 tile fit in each corner of a 2x2 tile.

Just some precisons in the doc could be enought.

[fossegutten]

Rect2.encloses method is inconsistent now.
When it checks for >= on top and left side, but < on right and bottom sides. Agree with @AlexHolly that it should be changed to <=.
Alternatively > and < on encloses method, and make a new "contains" method, that uses >= and <=.
Edit: typo

[Xrayez]

Some geometry methods follow non-strict inequalities already:

godot/doc/classes/Geometry.xml

Lines 219 to 242 in 0827258

	<method name="is_point_in_circle">
	<return type="bool">
	</return>
	<argument index="0" name="point" type="Vector2">
	</argument>
	<argument index="1" name="circle_position" type="Vector2">
	</argument>
	<argument index="2" name="circle_radius" type="float">
	</argument>
	<description>
	Returns [code]true[/code] if [code]point[/code] is inside the circle or if it's located exactly [i]on[/i] the circle's boundary, otherwise returns [code]false[/code].
	</description>
	</method>
	<method name="is_point_in_polygon">
	<return type="bool">
	</return>
	<argument index="0" name="point" type="Vector2">
	</argument>
	<argument index="1" name="polygon" type="PoolVector2Array">
	</argument>
	<description>
	Returns [code]true[/code] if [code]point[/code] is inside [code]polygon[/code] or if it's located exactly [i]on[/i] polygon's boundary, otherwise returns [code]false[/code].
	</description>
	</method>

I've also had to define some constant to emulate strictness (copied directly from my custom camera class to be enclosed within world limits):

const LIMIT_MARGIN = 1.0 # if 0.0 - strictly enclosed