I'm trying to animate circles to achieve an infinite effect of colliding waves.

I laid the base but I can't make the order of the animations smooth and linear.

Codepen available here.

<div 
    <!-- 1er circle -->
    <svg width="1280" height="1280" xmlns="http://www.w3.org/2000/svg" style="z-index: 1;">
      <path  d="M0 0h640c0 353.466-286.534 640-640 640V0Z" fill="currentColor" fill-rule="evenodd" />
    </svg>
    <!-- 2eme circle -->
    <svg width="1280" height="1280" xmlns="http://www.w3.org/2000/svg" style="z-index: 2;">
      <path  d="M0 0h640c0 353.466-286.534 640-640 640V0Z" fill="currentColor" fill-rule="evenodd" />
    </svg>
    <!-- 3eme circle -->
    <svg width="1280" height="1280" xmlns="http://www.w3.org/2000/svg" style="z-index: 3;">
      <path  d="M0 0h640c0 353.466-286.534 640-640 640V0Z" fill="currentColor" fill-rule="evenodd" />
    </svg>
</div>


.circles-container { position: relative; }

.circles-container svg {
  position: absolute;
  top: 0;
  left: 0;
}

.circle-1 {
  animation: scaleCircle 7.5s ease-in-out infinite;
  transform: scale(0);
  transition: all 2s ease-in-out;
  color: #1D1D28;
}

.circle-2 {
  animation: scaleCircle 5s ease-in-out infinite 2.5s;
  transform: scale(0);
  transition: all 2s ease-in-out;
  color: #420DC4;
}

.circle-3 {
  animation: scaleCircle 5s ease-in-out infinite;
  transform: scale(0);
  transition: all 2s ease-in-out;
  color: #1D1D28;
}

@keyframes scaleCircle {
  0% {
    transform: scale(0);
  }

  100% {
    transform: scale(2);
  }
}

Here is the scenario:

When loading, a first blue circle is displayed.

1. A first black circle grows until it crushes the blue circle
2. at 50% of step's 1 animation, a new blue circle is displayed and enlarged until it overwrites the black circle created during step 1
3. back to step 1

In my render, you can see that the circles are showing but some are hiding too soon, etc. The circles should display one after the other in a linear fashion.

Is it possible to do this in full CSS with keyframes ?

CodePudding user response：

Not sure if this is exactly what you are going for but maybe you can tinker with it.

So with 4 circles you can animate the scale basically the way you have it. And then for their svg container, you animate the z-index so whenever a wave starts it gets its highest z-index and then it deceases before the next wave starts.

<div >
  
  <!-- 1er cercle -->
  <svg  width="1280" height="1280" xmlns="http://www.w3.org/2000/svg">
    <path  d="M0 0h640c0 353.466-286.534 640-640 640V0Z" fill="currentColor" fill-rule="evenodd" />
  </svg>

  <!-- 2eme cercle -->
  <svg   width="1280" height="1280" xmlns="http://www.w3.org/2000/svg" >
    <path  d="M0 0h640c0 353.466-286.534 640-640 640V0Z" fill="currentColor" fill-rule="evenodd" />
  </svg>
  
  <svg   width="1280" height="1280" xmlns="http://www.w3.org/2000/svg" >
    <path  d="M0 0h640c0 353.466-286.534 640-640 640V0Z" fill="currentColor" fill-rule="evenodd" />
  </svg>
  

  <svg   width="1280" height="1280" xmlns="http://www.w3.org/2000/svg" >
    <path  d="M0 0h640c0 353.466-286.534 640-640 640V0Z" fill="currentColor" fill-rule="evenodd" />
  </svg>
  
body {
  margin: 0;
  padding: 0;
}

.circles-container { position: relative; }

.circles-container svg {
  position: absolute;
  top: 0;
  left: 0;
}

.circle-parent-1 {
  animation: zIndexCircle 8s ease-in-out infinite;
  animation-delay: 0s;
}

.circle-parent-2 {
  animation: zIndexCircle 8s ease-in-out infinite;
  animation-delay: 2s;
}

.circle-parent-3 {
  animation: zIndexCircle 8s ease-in-out infinite;
  animation-delay: 4s;
}

.circle-parent-3 {
  animation: zIndexCircle 8s ease-in-out infinite;
  animation-delay: 4s;
}
.circle-parent-4 {
  animation: zIndexCircle 8s ease-in-out infinite;
  animation-delay: 6s;
}


.circle-1 {
  animation: scaleCircle 8s ease-in-out infinite;
  animation-delay:0s;
  transform: scale(0);
  color: #1D1D28;
}

.circle-2 {
  animation: scaleCircle 8s ease-in-out infinite;
  animation-delay:2s;
  transform: scale(0);
  color: #420DC4;
}

.circle-3 {
  animation: scaleCircle 8s ease-in-out infinite;
  animation-delay:4s;
  transform: scale(0);
  color: #1D1D28;
}

.circle-4 {
  animation: scaleCircle 8s ease-in-out infinite;
  animation-delay:6s;
  transform: scale(0);
  color: #420DC4;
}

@keyframes zIndexCircle {
    0% {
    z-index:5;
  }
  25% {
    z-index: 4;
  }
  50% {
    z-index:3;
  }
  75% {
    z-index:2;
  }
  
  100% {
    z-index:1;
  }
}
@keyframes scaleCircle {
  0% {
    transform: scale(0);
  }
  75% {
     transform: scale(2);
  } 
  100% {
    transform: scale(2);
  }
}

https://codepen.io/todilo-the-vuer/pen/XWEmdXL