Snowfall

  • 1
  • Question
  • Updated 3 years ago
  • Answered
I'd love to be able to make a falling snow effect on a screen... any thoughts?!
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Thomas Pitts

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  • Christmassy!

Posted 3 years ago

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Ashleigh

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Hi Thomas!

I provided a code for that in this post: https://community.risevision.com/rise_vision_inc/topics/free-resources-to-help-you-design-great-digi...

You will need to use the HTML tag and paste it between the <body> tags. Then, stretch that HTML placeholder to fit the entire screen in your editor.

Let me know if you run into any issues!

Thanks
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Thomas Pitts

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Thank you. Should it appear in the preview? http://bit.ly/1XOpyv2
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John Iannelli

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I cannot seem to get this to work.  Can you give me some help?  I created a new presentation, the put a placeholder on it, choose HTML, copy and pasted the code into the placeholder, saved and previewed it.  Oh....changed the background to a color so I could see the snow but nothing happens.
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Thomas Pitts

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It's not working for me either - will it only work with the new editor? I can't check the live screen until Monday.
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Ashleigh

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Hi,

Apologies. Sometimes the code gets mixed up when using the code tag with our community platform.

Here is the working code:

<body><canvas id="canvas"></canvas>

<style>
* {margin: 0; padding: 0;}

}
canvas {
display: block;
}

</style>

<script>
    window.onload = function(){
//canvas init
var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");

//canvas dimensions
var W = window.innerWidth;
var H = window.innerHeight;
canvas.width = W;
canvas.height = H;

//snowflake particles
var mp = 25; //max particles
var particles = [];
for(var i = 0; i < mp; i++)
{
particles.push({
x: Math.random()*W, //x-coordinate
y: Math.random()*H, //y-coordinate
r: Math.random()*4+1, //radius
d: Math.random()*mp //density
})
}

//Lets draw the flakes
function draw()
{
ctx.clearRect(0, 0, W, H);

ctx.fillStyle = "rgba(255, 255, 255, 0.8)";
ctx.beginPath();
for(var i = 0; i < mp; i++)
{
var p = particles[i];
ctx.moveTo(p.x, p.y);
ctx.arc(p.x, p.y, p.r, 0, Math.PI*2, true);
}
ctx.fill();
update();
}

//Function to move the snowflakes
//angle will be an ongoing incremental flag. Sin and Cos functions will be applied to it to create vertical and horizontal movements of the flakes
var angle = 0;
function update()
{
angle += 0.01;
for(var i = 0; i < mp; i++)
{
var p = particles[i];
//Updating X and Y coordinates
//We will add 1 to the cos function to prevent negative values which will lead flakes to move upwards
//Every particle has its own density which can be used to make the downward movement different for each flake
//Lets make it more random by adding in the radius
p.y += Math.cos(angle+p.d) + 1 + p.r/2;
p.x += Math.sin(angle) * 2;

//Sending flakes back from the top when it exits
//Lets make it a bit more organic and let flakes enter from the left and right also.
if(p.x > W+5 || p.x < -5 || p.y > H)
{
if(i%3 > 0) //66.67% of the flakes
{
particles[i] = {x: Math.random()*W, y: -10, r: p.r, d: p.d};
}
else
{
//If the flake is exitting from the right
if(Math.sin(angle) > 0)
{
//Enter from the left
particles[i] = {x: -5, y: Math.random()*H, r: p.r, d: p.d};
}
else
{
//Enter from the right
particles[i] = {x: W+5, y: Math.random()*H, r: p.r, d: p.d};
}
}
}
}
}

//animation loop
setInterval(draw, 33);
}

</script>
</body>
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Thomas Pitts

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Fab! Seems to be working now. Thank you.
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Ashleigh

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Matt,

Did I -SAY- you could steal my thunder?!

Kidding, those look great! 
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mlm, Official Rep

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If you are interested in thunder you could always trigger a mp3 with GSAP and do a svg animation for the lightning.
http://codepen.io/MAW/pen/dYXObP