Hello all, welcome to this week’s tech update for You’re Doomed! One of the things we’ve been getting sorted this week is the Sludge Puddles the Chucker enemy throws at the players, this has been on my to-do list for a while so it was time to bite the laser bullet and just get it do. We’ve have had a version of the chucker’s sludge puddles in the game for some time now, but the method we used for them has been problematic. Until now the puddles were created as physical geometry (see the GIF below), because this gave us a lot of control over how the puddles looked, but this limited the puddles to only appearing on flat ground as the puddle geometry is a set shape and can’t deform over a non-uniform surface.
The main problem with this is that the levels are designed to have ledges and walk ways through out the them (to increase the visual fidelity of the levels), this obviously is not flat ground so the geometry based sludge puddles couldn’t work here (this is the reason why the levels are flat in the last pre-alpha build). To try and solve this issue we’ve looked at a number of solutions, the first was to make the puddle geometry a soft body and allow it to deform over the level geometry, however this was far to unpredictable in its deforming behaviour so the idea was quickly scrapped. The second solution was to use meta-balls with physical simulations make the puddles more dynamic and fluid like, however we couldn’t overcome the performance impact of this (it tanked the frame rate) so we gave this idea up too. After this we actually shelved the problem for a later date as it was taking too long to solve, but this week was that date so yours truly had to find a viable solution...And we’ve finally settled on a particle based solution and I’m super happy with it.
In the new method the Sludge is rendered as a particle effect with expanding and popping bubbles of sludge and a green tinged steam. Each bubble of sludge is a spherical mesh particle, and the material applied to them uses the alpha channel to eat through the rendered geometry to create the popping effect. The complete puddle is actually made up of 7 different smaller and fully independent puddles, each once of these puddles monitors agents entering and leaving their area of influence so that they can each individually apply their status effects to those agents. When the small puddles are spawned a ray is drawn through the level to find the highest piece of geometry where the puddle will be, and then the puddle is placed on top of that geometry, because of this the puddles give the appearance of building up over non uniform surfaces.
We’ve now also added the ability for players to destroy the sludge puddles by shooting them with a charged shot from their weapon, because the sludge puddle is actually 7 smaller independent puddles each puddle can be destroyed individually by the charged shot, this can give the appearance of the shot tearing through and destroying parts of the large puddle.
We’re also working on getting a new pre-alpha build out soon, so the new sludge, weapons, gameplay, and levels(!) should be with you soon! For now here’s a sneak peek at the mines levels
I hope you all enjoy your weekend!
Jules