I am having an issue with scope, I think?
I am unsure why this.wheel_on_ground always returns a FALSE when I check it in the update_position function. The raytrace is showing TRUE, as the log code shows, but checking the value in the other function or the main update just returns FALSE no matter what.
Ok, here’s my code, I’ve cut out some unrelated bits to get to the source issue:
pc.script.create('Robot_movement', function (app) {
// Creates a new Robot_movement instance
var Robot_movement = function (entity) {
this.entity = entity;
//////////////////////////////////////////////////
this.wheel_on_ground = false; //is the wheel of the player on the ground?
this.groundCheckRay = new pc.Vec3(0,-this.ground_check_distance,0);
this.rayEnd = new pc.Vec3();
};
Robot_movement.prototype = {
// Called once after all resources are loaded and before the first update
initialize: function () {
},
/////////////////////////////////////
update_wheel_on_ground: function() {
//var po = this.entity.getPosition();
this.groundCheckRay.x = 0;
this.groundCheckRay.y = -this.ground_check_distance;
this.groundCheckRay.z = 0;
this.rayEnd.add2(this.entity.getPosition(), this.groundCheckRay);
//console.log("rayEnd is " + this.rayEnd);
this.wheel_on_ground = false;
// Fire a ray straight down to just below the bottom of the rigid body,
// if it hits something then the character is standing on something.
app.systems.rigidbody.raycastFirst(this.entity.getPosition(), this.rayEnd, function (result) {
this.wheel_on_ground = true;
console.log("Raytrace returned a target, wheel_on_ground is set to " + this.wheel_on_ground); //<-- This is returning TRUE in the console.
});
},
update_position: function() {
console.log("update_position the wheel_on_ground is equal to " + this.wheel_on_ground); //<-- Yet this is always returning FALSE, despite running later
//if the wheel is touching the ground
if(this.wheel_on_ground){
//move robot forwards
//I removed code here, but it's basically pushing the object forwards if the wheel_on_ground is TRUE.
} //end of if wheel is on ground brackets
},
// Called every frame, dt is time in seconds since last update
update: function (dt) {
this.update_wheel_on_ground();
this.update_position(); //push the player object based on speed.
}
};
return Robot_movement;
});
I’m sure I’m just missing something very basic, but shouldn’t this.wheel_on_ground always refer to the entity’s property I defined at the beginning? According to this it should, the paused, amplitude, and timer variables are described as working that way in the example: http://developer.playcanvas.com/en/user-manual/scripting/anatomy/
But somehow I’m losing the value in my setup. Is it because “this” changes target somewhere along the way? If so, why?
