Valves, splitters and timing in Mixmatics
The early chapters of Mixmatics are about where liquid goes. The later ones are about when. Sequenced orders, shared outputs and mixers that need two colours at once all depend on timing, and timing depends on understanding how the simulation moves each drop. This guide covers the rules of movement, then the pieces that control it: tees, splitters and programmable valves.
How liquid moves
Mixmatics runs in ticks, and every unit of liquid behaves the same way:
- One cell per tick. A unit moves at most one cell each tick, so a pipe ten cells long takes ten ticks to cross.
- One unit per pipe. An ordinary pipe holds a single unit. A full line advances together, like a queue.
- Sources release one unit per tick, whenever their outlet is clear.
- No unit ever turns back the way it came.
- When two flows meet, the one entering from the top goes first, then the right, then the bottom, then the left.
Those five rules explain almost everything you see when you press Run. If two colours arrive at a mixer at different times, count the cells on each path: the difference is the delay in ticks.
Tees: alternating exits
A tee has one inlet and two possible exits. It does not split a single unit; instead, it alternates: the first unit goes one way, the next goes the other, and so on. If the exit it is due to use is blocked, the unit waits rather than switching to the other side.
That makes a tee a simple way to share one source between two destinations, as long as both can keep accepting liquid.
Splitters: dividing a flow
From Chapter 4, splitters appear on the board. A splitter takes liquid in from below and sends it out to the left and right in turn, giving an even one-to-one split. Like a tee, it waits if its next exit is blocked.
Splitter puzzles usually have two orders to fill from one source. Count how many units each order needs: an even split means a source of eight units can fill two orders of four. If one order needs more, the extra must come from somewhere else, or the split must happen further along the line.
Valves: controlling when
A valve looks like a straight pipe, but you can program it. It starts open, and a closed valve neither accepts nor releases liquid, holding whatever is inside it.
A valve program is a short list of steps, run in order:
| Step | What it does |
|---|---|
| Open | Opens the valve straight away and moves to the next step |
| Close | Closes the valve straight away and moves to the next step |
| Delay n | Waits n ticks before moving on |
| Release n | Stays open until n units have passed, then closes |
| Wait for sensor | Waits until a chosen sensor has liquid in it |
A program can hold up to sixteen steps and can be set to loop back to the start.
The most useful program by far is Close, Delay n, Open. It holds one colour back for exactly n ticks and then lets it through. Almost every timing puzzle in the campaign can be solved with that pattern; the skill is choosing n.
Sequenced orders
Chapter 3 introduces orders marked as a sequence: they need, say, two red and then two blue, and they will not accept the blue until the red is complete. Any blue that arrives early is discarded as waste.
The usual set-up has two sources feeding one order through a merging pipe. Put a valve on the line that must go second and program it with Close, Delay n, Open. To choose n:
- Count the first colour's arrival. How many ticks until its last unit reaches the order? That is roughly the path length plus the number of units.
- Count the second colour's path. How many ticks does it take from the valve to the order?
- Set the delay so the second colour arrives just after the first finishes. Too short and units are wasted; too long and you lose cycles.
Step through the run tick by tick to check. If a unit is discarded, increase the delay by one; if the order sits idle waiting, decrease it.
Mixers and timing
Mixers need their two colours together. If one input arrives early, two units of the same colour can fill the mixer's buffer and jam it. Two fixes work:
- Balance the paths, so both colours travel the same number of cells.
- Hold back the faster side with a valve and a short delay.
Balanced paths are usually better: they cost no actions to program and add no cycles.
Where the chapters take you
| Chapter | Name | What it adds |
|---|---|---|
| 1 | First Drops | Pipes and routing |
| 2 | Colour Chemistry | Mixers and recipes |
| 3 | Valve Workshop | Valves, sequenced orders and filters |
| 4 | Split Decisions | Splitters and two orders at once |
| 5 | Production Line | Chambers and treated orders |
| 6 | Factory Automation | Everything so far, combined |
| 7 | Resource Crisis | Energy and pipe limits on some puzzles |
| 8 | Master Factory | The hardest combinations |
Each chapter has 25 puzzles, and finishing 15 opens the next. By Chapter 6 you will be timing valves, balancing mixers and splitting flows in the same factory, and the rules on this page are the ones that make it work.