将鼠标事件转换为移动触摸事件

时间:2015-06-29 10:37:19

标签: javascript cordova

我正在尝试使用从互联网收集的以下代码(抱歉,我忘记了网址)。它应该在桌面浏览器中运行良好。但我想在移动设备上使用它(可能与cordova一起使用)。我试图用等效的触摸事件来改变鼠标事件而没有运气。那么,任何人都可以帮我定制移动设备。

                <!DOCTYPE html>

        <html>

          <head>

            <meta charset="utf-8">

            <title>Physics + Particles Mashup</title>

        <script src="jquery-1.11.1.js"></script>



        <STYLE type="text/css">

        /* basic styles for black background and crosshair cursor */
        body {
            background: #000;
            margin: 0;
        }

        canvas {
            cursor: crosshair;
            display: block;
        }

        </STYLE>

        </head>

        <body>

        <!-- setup our canvas element -->

        <canvas id="canvas">Canvas is not supported in your browser.</canvas>

        <script type="text/javascript">

        window.requestAnimFrame = ( function() {
            return window.requestAnimationFrame ||
                        window.webkitRequestAnimationFrame ||
                        window.mozRequestAnimationFrame ||
                        function( callback ) {
                            window.setTimeout( callback, 1000 / 60 );
                        };
        })();

        // now we will setup our basic variables for the demo

        var canvas = document.getElementById( 'canvas' ),
                ctx = canvas.getContext( '2d' ),
                // full screen dimensions
                cw = window.innerWidth,
                ch = window.innerHeight,
                // firework collection
                fireworks = [],
                // particle collection
                particles = [],
                // starting hue
                hue = 120,
                // when launching fireworks with a click, too many get launched at once without a limiter, one launch per 5 loop ticks
                limiterTotal = 5,
                limiterTick = 0,
                // this will time the auto launches of fireworks, one launch per 80 loop ticks
                timerTotal = 80,
                timerTick = 0,
                mousedown = false,
                // mouse x coordinate,
                mx,
                // mouse y coordinate
                my;

        // set canvas dimensions
        canvas.width = cw;
        canvas.height = ch;

        // now we are going to setup our function placeholders for the entire demo

        // get a random number within a range
        function random( min, max ) {
            return Math.random() * ( max - min ) + min;
        }

        // calculate the distance between two points
        function calculateDistance( p1x, p1y, p2x, p2y ) {
            var xDistance = p1x - p2x,
                    yDistance = p1y - p2y;
            return Math.sqrt( Math.pow( xDistance, 2 ) + Math.pow( yDistance, 2 ) );
        }

        // create firework
        function Firework( sx, sy, tx, ty ) {
            // actual coordinates
            this.x = sx;
            this.y = sy;
            // starting coordinates
            this.sx = sx;
            this.sy = sy;
            // target coordinates
            this.tx = tx;
            this.ty = ty;
            // distance from starting point to target
            this.distanceToTarget = calculateDistance( sx, sy, tx, ty );
            this.distanceTraveled = 0;
            // track the past coordinates of each firework to create a trail effect, increase the coordinate count to create more prominent trails
            this.coordinates = [];
            this.coordinateCount = 3;
            // populate initial coordinate collection with the current coordinates
            while( this.coordinateCount-- ) {
                this.coordinates.push( [ this.x, this.y ] );
            }
            this.angle = Math.atan2( ty - sy, tx - sx );
            this.speed = 2;
            this.acceleration = 1.05;
            this.brightness = random( 50, 70 );
            // circle target indicator radius
            this.targetRadius = 1;
        }

        // update firework
        Firework.prototype.update = function( index ) {
            // remove last item in coordinates array
            this.coordinates.pop();
            // add current coordinates to the start of the array
            this.coordinates.unshift( [ this.x, this.y ] );

            // cycle the circle target indicator radius
            if( this.targetRadius < 8 ) {
                this.targetRadius += 0.3;
            } else {
                this.targetRadius = 1;
            }

            // speed up the firework
            this.speed *= this.acceleration;

            // get the current velocities based on angle and speed
            var vx = Math.cos( this.angle ) * this.speed,
                    vy = Math.sin( this.angle ) * this.speed;
            // how far will the firework have traveled with velocities applied?
            this.distanceTraveled = calculateDistance( this.sx, this.sy, this.x + vx, this.y + vy );

            // if the distance traveled, including velocities, is greater than the initial distance to the target, then the target has been reached
            if( this.distanceTraveled >= this.distanceToTarget ) {
                createParticles( this.tx, this.ty );
                // remove the firework, use the index passed into the update function to determine which to remove
                fireworks.splice( index, 1 );
            } else {
                // target not reached, keep traveling
                this.x += vx;
                this.y += vy;
            }
        }

        // draw firework
        Firework.prototype.draw = function() {
            ctx.beginPath();
            // move to the last tracked coordinate in the set, then draw a line to the current x and y
            ctx.moveTo( this.coordinates[ this.coordinates.length - 1][ 0 ], this.coordinates[ this.coordinates.length - 1][ 1 ] );
            ctx.lineTo( this.x, this.y );
            ctx.strokeStyle = 'hsl(' + hue + ', 100%, ' + this.brightness + '%)';
            ctx.stroke();

            ctx.beginPath();
            // draw the target for this firework with a pulsing circle
            ctx.arc( this.tx, this.ty, this.targetRadius, 0, Math.PI * 2 );
            ctx.stroke();
        }

        // create particle
        function Particle( x, y ) {
            this.x = x;
            this.y = y;
            // track the past coordinates of each particle to create a trail effect, increase the coordinate count to create more prominent trails
            this.coordinates = [];
            this.coordinateCount = 8;
            while( this.coordinateCount-- ) {
                this.coordinates.push( [ this.x, this.y ] );
            }
            // set a random angle in all possible directions, in radians
            this.angle = random( 0, Math.PI * 2 );
            this.speed = random( 1, 10 );
            // friction will slow the particle down
            this.friction = 0.95;
            // gravity will be applied and pull the particle down
            this.gravity = 1;
            // set the hue to a random number +-50 of the overall hue variable
            this.hue = random( hue - 50, hue + 50 );
            this.brightness = random( 50, 80 );
            this.alpha = 1;
            // set how fast the particle fades out
            this.decay = random( 0.015, 0.03 );
        }

        // update particle
        Particle.prototype.update = function( index ) {
            // remove last item in coordinates array
            this.coordinates.pop();
            // add current coordinates to the start of the array
            this.coordinates.unshift( [ this.x, this.y ] );
            // slow down the particle
            this.speed *= this.friction;
            // apply velocity
            this.x += Math.cos( this.angle ) * this.speed;
            this.y += Math.sin( this.angle ) * this.speed + this.gravity;
            // fade out the particle
            this.alpha -= this.decay;

            // remove the particle once the alpha is low enough, based on the passed in index
            if( this.alpha <= this.decay ) {
                particles.splice( index, 1 );
            }
        }

        // draw particle
        Particle.prototype.draw = function() {
            ctx. beginPath();
            // move to the last tracked coordinates in the set, then draw a line to the current x and y
            ctx.moveTo( this.coordinates[ this.coordinates.length - 1 ][ 0 ], this.coordinates[ this.coordinates.length - 1 ][ 1 ] );
            ctx.lineTo( this.x, this.y );
            ctx.strokeStyle = 'hsla(' + this.hue + ', 100%, ' + this.brightness + '%, ' + this.alpha + ')';
            ctx.stroke();
        }

        // create particle group/explosion
        function createParticles( x, y ) {
            // increase the particle count for a bigger explosion, beware of the canvas performance hit with the increased particles though
            var particleCount = 30;
            while( particleCount-- ) {
                particles.push( new Particle( x, y ) );
            }
        }

        // main demo loop
        function loop() {
            // this function will run endlessly with requestAnimationFrame
            requestAnimFrame( loop );

            // increase the hue to get different colored fireworks over time
            //hue += 0.5;

          // create random color
          hue= random(0, 360 );

            // normally, clearRect() would be used to clear the canvas
            // we want to create a trailing effect though
            // setting the composite operation to destination-out will allow us to clear the canvas at a specific opacity, rather than wiping it entirely
            ctx.globalCompositeOperation = 'destination-out';
            // decrease the alpha property to create more prominent trails
            ctx.fillStyle = 'rgba(0, 0, 0, 0.5)';
            ctx.fillRect( 0, 0, cw, ch );
            // change the composite operation back to our main mode
            // lighter creates bright highlight points as the fireworks and particles overlap each other
            ctx.globalCompositeOperation = 'lighter';

            // loop over each firework, draw it, update it
            var i = fireworks.length;
            while( i-- ) {
                fireworks[ i ].draw();
                fireworks[ i ].update( i );
            }

            // loop over each particle, draw it, update it
            var i = particles.length;
            while( i-- ) {
                particles[ i ].draw();
                particles[ i ].update( i );
            }

            // launch fireworks automatically to random coordinates, when the mouse isn't down


            // limit the rate at which fireworks get launched when mouse is down
            if( limiterTick >= limiterTotal ) {
                if( mousedown ) {
                    // start the firework at the bottom middle of the screen, then set the current mouse coordinates as the target
                    fireworks.push( new Firework( cw / 2, ch, mx, my ) );
                    limiterTick = 0;
                }
            } else {
                limiterTick++;
            }
        }

        // mouse event bindings
        // update the mouse coordinates on mousemove
        canvas.addEventListener( 'mousemove', function( e ) {
            mx = e.pageX - canvas.offsetLeft;
            my = e.pageY - canvas.offsetTop;
        });

        // toggle mousedown state and prevent canvas from being selected
        canvas.addEventListener( 'mousedown', function( e ) {
            e.preventDefault();
            mousedown = true;
        });

        canvas.addEventListener( 'mouseup', function( e ) {
            e.preventDefault();
            mousedown = false;
        });

        // once the window loads, we are ready for some fireworks!
        window.onload = loop;



        </script>

        </body>

        </html>

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提前致谢。

0 个答案:

没有答案