File indexing completed on 2024-04-28 15:07:52

 /* GCompris - gravity.js
 *
 * SPDX-FileCopyrightText: 2020 Timothée Giet <animtim@gmail.com>
 *
 * Authors:
 *   Bruno Coudoin <bruno.coudoin@gcompris.net> and Matilda Bernard (GTK+ version)
 *   Siddhesh suthar <siddhesh.it@gmail.com> (Qt Quick port)
 *   Timothée Giet <animtim@gmail.com> (complete activity rewrite)
 *
 *   SPDX-License-Identifier: GPL-3.0-or-later
 */
 .pragma library
 .import QtQuick 2.12 as Quick
 .import "qrc:/gcompris/src/core/core.js" as Core
 
 var url = "qrc:/gcompris/src/activities/gravity/resource/"
 
 var levels = [
             { // Level 1
                 planetFrequency: 12000,
                 planetCount: 5
             },
             { // Level 2
                 planetFrequency: 10000,
                 planetCount: 10
             },
             { // Level 3
                 planetFrequency: 8000,
                 planetCount: 15
             },
             { // Level 4
                 planetFrequency: 7000,
                 planetCount: 20
             },
             { // Level 5
                 planetFrequency: 6000,
                 planetCount: 25
             },
             { // Level 6
                 planetFrequency: 5000,
                 planetCount: 30
             }
         ]
 
 var numberOfLevel = levels.length;
 var items;
 var message;
 
 // delta move
 var move = 0;
 // control move
 var controlMove = 0;
 // gravity of current planet
 var planetGravity = 0;
 // speed for key controls
 var controlSpeed = 0.2;
 
 var currentPlanet;
 var planetsCounter = 0;
 
 function start(items_,message_) {
     items = items_;
     items.currentLevel = Core.getInitialLevel(numberOfLevel);
     message = message_;
     initLevel();
 }
 
 function stop() {
     items.processTimer.stop();
     items.planetCreation.stop();
     destroyPlanet();
     planetsCounter = 0;
     controlMove = 0;
     move = 0;
 }
 
 function initLevel() {
     stop();
     items.planetFrequency = levels[items.currentLevel].planetFrequency;
     items.background.initSpace();
     items.explosion.hide();
     items.spaceship.opacity = 100;
     items.spaceshipX = items.background.width * 0.5;
     items.stationDown.stop();
     items.station.y = -items.station.height;
     controlSpeed = 0.2 * (items.currentLevel * 0.25 + 1);
     if(!items.startMessage) {
         items.processTimer.start();
         createPlanet();
         items.planetCreation.start();
         message.index = -1;
     } else {
         message.index = 0;
     }
 }
 
 function nextLevel() {
     items.currentLevel = Core.getNextLevel(items.currentLevel, numberOfLevel);
     initLevel();
 }
 
 function previousLevel() {
     items.currentLevel = Core.getPreviousLevel(items.currentLevel, numberOfLevel);
     initLevel();
 }
 
 function processKeyPress(event) {
     var key = event.key;
     event.accepted = true;
     if(key === Qt.Key_Left) {
         controlMove += -controlSpeed;
     } else if(key === Qt.Key_Right) {
         controlMove += controlSpeed;
     }
 }
 
 function processKeyRelease(event) {
     var key = event.key;
     event.accepted = true;
     if(key === Qt.Key_Left || key === Qt.Key_Right) {
         controlMove = 0;
     }
 }
 
 function createPlanet() {
     if(planetsCounter < levels[items.currentLevel].planetCount) {
         var planetSide = Math.floor( Math.random() * 2);  
         var planetSize = Math.max(Math.random() * items.maxPlanetSize, items.minPlanetSize);
         if(planetSide == 0) {
             currentPlanet = items.planet0;
         } else if(planetSide == 1) {
             currentPlanet = items.planet1;
         }
         currentPlanet.source = url + "planet" + Math.floor(Math.random() * 2) + ".webp";
         currentPlanet.fallDuration = levels[items.currentLevel].planetFrequency;
         currentPlanet.height = planetSize;
         currentPlanet.width = planetSize;
         currentPlanet.y = currentPlanet.height * -2;
         currentPlanet.visible = true;
         currentPlanet.startMoving();
         planetGravity = currentPlanet.leftSide ? -currentPlanet.width * 0.5: currentPlanet.width * 0.5;
         planetsCounter++;
     } else {
         items.stationDown.restart();
     }
 }
 
 function moveSpaceship() {
     // calculate gravity
     if(planetsCounter > 0) {
         // calculate distance between planet center and spaceship center
         var hypothenuse = Math.sqrt(
             Math.pow((currentPlanet.x + (currentPlanet.width * 0.5)) - items.spaceshipX, 2) +
             Math.pow((currentPlanet.y + (currentPlanet.height * 0.5)) - items.spaceshipY, 2));
         items.gravity = (planetGravity * (items.currentLevel * 0.33 + 1)) / Math.pow(hypothenuse, 2) * 100;
     } else {
         items.gravity = 0;
     }
     move += controlMove + (items.gravity);
     items.spaceshipX += move;
 
     // Check for crash
     computeOverlap();
 
     // Don't go out of the screen or stay stuck on the borders
     if(items.spaceshipX > items.background.width - items.borderMargin) {
         move = 0;
         controlMove = 0;
         items.spaceshipX -= 1;
     } else if(items.spaceshipX < items.borderMargin) {
         move = 0;
         controlMove = 0;
         items.spaceshipX += 1;
     }
 }
 
 function computeOverlap() {
     if(planetsCounter > 0) {
         // compute overlap with a little margin on the planets to not hit too much on corners
         var xOverlap = Math.min(items.spaceship.x + items.spaceship.width,
                                 currentPlanet.x + currentPlanet.width * 0.9) - 
                        Math.max(items.spaceship.x, currentPlanet.x + currentPlanet.width * 0.1);
         var yOverlap = Math.min(items.spaceship.y + items.spaceship.height,
                                 currentPlanet.y + currentPlanet.height * 0.9) - 
                        Math.max(items.spaceship.y, currentPlanet.y +
                                 currentPlanet.height * 0.1);
         // again add a safety margin to avoid hitting on corners
         if(xOverlap > items.spaceship.width * 0.2 && yOverlap > items.spaceship.height * 0.2) {
             crash();
             items.bonus.bad("lion");
         }
     }
 }
 
 function destroyPlanet() {
     planetGravity = 0;
     items.gravity = 0;
     if(planetsCounter > 0) {
         currentPlanet.visible = false;
     }
 }
 
 function crash() {
     items.audioEffects.play("qrc:/gcompris/src/core/resource/sounds/crash.wav");
     items.explosion.show();
     items.spaceship.hide();
     stop();
 }