phaser/src/physics/arcade/GetOverlapY.js

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/**
* @author Richard Davey <rich@photonstorm.com>
* @copyright 2019 Photon Storm Ltd.
2019-05-10 15:15:04 +00:00
* @license {@link https://opensource.org/licenses/MIT|MIT License}
*/
var CONST = require('./const');
/**
* Calculates and returns the vertical overlap between two arcade physics bodies and sets their properties
* accordingly, including: `touching.up`, `touching.down`, `touching.none` and `overlapY'.
*
* @function Phaser.Physics.Arcade.GetOverlapY
* @since 3.0.0
*
* @param {Phaser.Physics.Arcade.Body} body1 - The first Body to separate.
* @param {Phaser.Physics.Arcade.Body} body2 - The second Body to separate.
* @param {boolean} overlapOnly - Is this an overlap only check, or part of separation?
* @param {number} bias - A value added to the delta values during collision checks. Increase it to prevent sprite tunneling(sprites passing through another instead of colliding).
*
* @return {number} The amount of overlap.
*/
var GetOverlapY = function (body1, body2, overlapOnly, bias)
{
var overlap = 0;
var maxOverlap = body1.deltaAbsY() + body2.deltaAbsY() + bias;
if (body1._dy === 0 && body2._dy === 0)
{
// They overlap but neither of them are moving
body1.embedded = true;
body2.embedded = true;
}
else if (body1._dy > body2._dy)
{
// Body1 is moving down and/or Body2 is moving up
overlap = body1.bottom - body2.y;
if ((overlap > maxOverlap && !overlapOnly) || body1.checkCollision.down === false || body2.checkCollision.up === false)
{
overlap = 0;
}
else
{
body1.touching.none = false;
body1.touching.down = true;
body2.touching.none = false;
body2.touching.up = true;
if (body2.physicsType === CONST.STATIC_BODY)
{
body1.blocked.none = false;
body1.blocked.down = true;
}
if (body1.physicsType === CONST.STATIC_BODY)
{
body2.blocked.none = false;
body2.blocked.up = true;
}
}
}
else if (body1._dy < body2._dy)
{
// Body1 is moving up and/or Body2 is moving down
overlap = body1.y - body2.bottom;
if ((-overlap > maxOverlap && !overlapOnly) || body1.checkCollision.up === false || body2.checkCollision.down === false)
{
overlap = 0;
}
else
{
body1.touching.none = false;
body1.touching.up = true;
body2.touching.none = false;
body2.touching.down = true;
if (body2.physicsType === CONST.STATIC_BODY)
{
body1.blocked.none = false;
body1.blocked.up = true;
}
if (body1.physicsType === CONST.STATIC_BODY)
{
body2.blocked.none = false;
body2.blocked.down = true;
}
}
}
// Resets the overlapY to zero if there is no overlap, or to the actual pixel value if there is
body1.overlapY = overlap;
body2.overlapY = overlap;
return overlap;
};
module.exports = GetOverlapY;