CRT effect on HTML published carts

Sat, 10 Feb 2024 23:45:54 UTC

Here's some code to add a old CRT monitor effect over your HTML-published carts.

I read an article recently about how low-res graphics looked better/softer on old CRT monitors and TVs, so did some googleing and found an effect you can apply via Cascading Style Sheets to your HTML-published game.

When you've export my_game.html open up the .html file in a text editor and add the following inside a STYLE tag near the top of the file:

  @keyframes flicker {
  0% {
    opacity: 0.27861;
  }
  5% {
    opacity: 0.34769;
  }
  10% {
    opacity: 0.23604;
  }
  15% {
    opacity: 0.90626;
  }
  20% {
    opacity: 0.18128;
  }
  25% {
    opacity: 0.83891;
  }
  30% {
    opacity: 0.65583;
  }
  35% {
    opacity: 0.67807;
  }
  40% {
    opacity: 0.26559;
  }
  45% {
    opacity: 0.84693;
  }
  50% {
    opacity: 0.96019;
  }
  55% {
    opacity: 0.08594;
  }
  60% {
    opacity: 0.20313;
  }
  65% {
    opacity: 0.71988;
  }
  70% {
    opacity: 0.53455;
  }
  75% {
    opacity: 0.37288;
  }
  80% {
    opacity: 0.71428;
  }
  85% {
    opacity: 0.70419;
  }
  90% {
    opacity: 0.7003;
  }
  95% {
    opacity: 0.36108;
  }
  100% {
    opacity: 0.24387;
  }
}
@keyframes textShadow {
  0% {
    text-shadow: 0.4389924193300864px 0 1px rgba(0,30,255,0.5), -0.4389924193300864px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  5% {
    text-shadow: 2.7928974010788217px 0 1px rgba(0,30,255,0.5), -2.7928974010788217px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  10% {
    text-shadow: 0.02956275843481219px 0 1px rgba(0,30,255,0.5), -0.02956275843481219px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  15% {
    text-shadow: 0.40218538552878136px 0 1px rgba(0,30,255,0.5), -0.40218538552878136px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  20% {
    text-shadow: 3.4794037899852017px 0 1px rgba(0,30,255,0.5), -3.4794037899852017px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  25% {
    text-shadow: 1.6125630401149584px 0 1px rgba(0,30,255,0.5), -1.6125630401149584px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  30% {
    text-shadow: 0.7015590085143956px 0 1px rgba(0,30,255,0.5), -0.7015590085143956px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  35% {
    text-shadow: 3.896914047650351px 0 1px rgba(0,30,255,0.5), -3.896914047650351px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  40% {
    text-shadow: 3.870905614848819px 0 1px rgba(0,30,255,0.5), -3.870905614848819px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  45% {
    text-shadow: 2.231056963361899px 0 1px rgba(0,30,255,0.5), -2.231056963361899px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  50% {
    text-shadow: 0.08084290417898504px 0 1px rgba(0,30,255,0.5), -0.08084290417898504px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  55% {
    text-shadow: 2.3758461067427543px 0 1px rgba(0,30,255,0.5), -2.3758461067427543px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  60% {
    text-shadow: 2.202193051050636px 0 1px rgba(0,30,255,0.5), -2.202193051050636px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  65% {
    text-shadow: 2.8638780614874975px 0 1px rgba(0,30,255,0.5), -2.8638780614874975px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  70% {
    text-shadow: 0.48874025155497314px 0 1px rgba(0,30,255,0.5), -0.48874025155497314px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  75% {
    text-shadow: 1.8948491305757957px 0 1px rgba(0,30,255,0.5), -1.8948491305757957px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  80% {
    text-shadow: 0.0833037308038857px 0 1px rgba(0,30,255,0.5), -0.0833037308038857px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  85% {
    text-shadow: 0.09769827255241735px 0 1px rgba(0,30,255,0.5), -0.09769827255241735px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  90% {
    text-shadow: 3.443339761481782px 0 1px rgba(0,30,255,0.5), -3.443339761481782px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  95% {
    text-shadow: 2.1841838852799786px 0 1px rgba(0,30,255,0.5), -2.1841838852799786px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
  100% {
    text-shadow: 2.6208764473832513px 0 1px rgba(0,30,255,0.5), -2.6208764473832513px 0 1px rgba(255,0,80,0.3), 0 0 3px;
  }
}
.crt::after {
  content: " ";
  display: block;
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
  background: rgba(18, 16, 16, 0.06);
  opacity: 0;
  z-index: 2;
  pointer-events: none;
  animation: flicker 0.15s infinite;
}
.crt::before {
  content: " ";
  display: block;
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
  background: linear-gradient(rgba(18, 16, 16, 0) 50%, rgba(0, 0, 0, 0.25) 50%), linear-gradient(90deg, rgba(255, 0, 0, 0.06), rgba(0, 255, 0, 0.02), rgba(0, 0, 255, 0.06));
  z-index: 2;
  background-size: 100% 3px, 3px 100%;
  pointer-events: none;
  backdrop-filter: blur(0.4px);
  mix-blend-mode: color-burn;
}
.crt {
  animation: textShadow 1.6s infinite;
}

Then find the line id="p8_playarea" style="display:none; margin:auto; and change it to add a class of 'crt' like this: id="p8_playarea" class="crt" style="display:none; margin:auto;

You can see a working version here: https://steveattewell.com/alien/index_crt.html
Go there and "view source" to see how it's done.

I adapted this code to get the effect working: https://aleclownes.com/2017/02/01/crt-display.html and did some tweaks and added some blur.

Destroy the Puny Humans - WIP (v0.5)

Sun, 05 Nov 2023 18:18:46 UTC

v0.5 Updated 3rd Dec 2023 - 2 players and some more levels

This is my first go at a Pico-8 game. Loving the Pico-8 and have learned a lot over the last couple of weeks.

V0.2 - Updated to include weapon power ups that give you faster firing rates
V0.4 - TANKS!!! cleaned up sounds. Extended music. Refactored map ready for multiple levels.
v0.5 - 2 Player option, 5 levels (then stops rather abruptly!), boats, homing missiles, water level, adjusted difficulty

Shoot the puny humans...

Pick up power ups for faster fire rate...

Save the animals for points and health boost...

How to play

Objective: Destroy the puny humans
Increase health by picking up the animals by flying low to the ground.
Increase fire rate by picking up Crystals
Increase speed by picking up stars
Kill ground enemies by dropping bombs.
Kill air enemies using your lasers!

You will get shot at so make sure you save as many animals as you can to increase your health.

How many points can you get? Would love to see score screenshots :)

There may be bugs - please report if you find any. And let me know what the difficulty level is like.

Destroy the puny humans v0.5

by progbod

[Click to Play]

Next steps

add more levels
Bug: pickups, crashes and bullets still seem to hit player when dead in 2 player mode.
only spawn power-ups when you haven’t reached max-speed and max-firepower.
Make there be a small chance of dropping a power if you get shot.
“SHIELDS” power up that gives you infinite shield for 30 seconds (or maybe bind to a button).

Thanks for your feedback.

progbod [Lexaloffle Blog Feed]

CRT effect on HTML published carts

Destroy the Puny Humans - WIP (v0.5)

v0.5 Updated 3rd Dec 2023 - 2 players and some more levels

How to play

Next steps