# fxSmoke A puff of smoke on a card facing the camera (`zero_billboard`), for blending over the frame. It draws a soft, lumpy disc of three-octave value noise whose edge is pushed in and out by the noise, and as the puff ages the noise thins it from its wisps inward. It is lit by the ambient light plus the sun, wrapped around a sphere normal under the card so the side toward the sun is brighter. The colour is the element's colour times that light, and the alpha is the density times the element's opacity times `gain`. The combat graphs beside it in `combat/` draw with it as `fxSmoke`, transparent. The `impact` graph uses it for the burst of dust and grit off the struck surface (grit colour `(0.58, 0.53, 0.46)`, opacity falling from 0.55 to 0 over life), and the `muzzleFlash` graph for the puffs of smoke leaving the bore (grey `(0.56, 0.54, 0.52)`, opacity falling from 0.42 to 0). Both swell the card as it ages. The `bench_mixed` scene places both graphs and the `main` scene places `muzzleFlash`. The shader includes `@builtin::shaderModules.billboard`. ## Properties | Property | Type | Default | Meaning | |---|---|---|---| | `gain` | float | 1.0 | Multiplies the output alpha. | | `vertexBoundsDilation` | float | 5 | How far the vertex hook moves a vertex past the mesh, in world units: the culling bounds grow by it so a moved vertex stays inside them. | ## Lanes | Lane | Carries | |---|---| | `data0.rgb` | Smoke colour, multiplied by the lighting. | | `data1.x` | Seed: picks the puff's lumps. | | `data1.y` | Life, 0 at birth to 1 at death: thins the puff and drifts its noise. | | `data1.z` | Opacity. |

# fxFlash The bloom of a discharge, drawn procedurally on a card for additive blending. With `shape` 0 it is a ragged star facing the camera (`zero_billboard`): five to seven spikes of hashed length and turn around a white-hot core, each spike brightest at its root and fading to its tip. With `shape` above 0.5 it is a tongue of flame on a card turned onto the element's Y axis (`zero_billboard_streak`), running from the middle of the card (the muzzle) to its tip along +Y, wavering at its edges and cooling toward the tip, on the half of the card between its middle and its +Y end. The petals are re-seeded every 1/30 s of world time, so a flash held for more than one frame flickers. The colour is the element's `data0` colour over the shape, plus a white `(1.0, 0.95, 0.85)` core scaled by the colour's brightest channel. The combat graphs beside it in `combat/` draw with it as `fxFlash`, additive. The `impact` graph draws two stars (`shape` 0) at the point of impact for three frames. The `muzzleFlash` graph draws three stars turned apart by their seeds (`shape` 0) and one tongue of flame down the bore (`shape` 1). Both colour the flash from an HDR ramp that falls to black over its short life. The `bench_mixed` scene places both graphs and the `main` scene places `muzzleFlash`. The shader includes `@builtin::shaderModules.billboard`. ## Properties | Property | Type | Default | Meaning | |---|---|---|---| | `gain` | float | 1.0 | Multiplies the output colour. | | `shape` | float | 0.0 | 0 draws the camera-facing star; above 0.5 draws the tongue along the element's Y axis. | | `vertexBoundsDilation` | float | 5 | How far the vertex hook moves a vertex past the mesh, in world units: the culling bounds grow by it so a moved vertex stays inside them. | ## Lanes | Lane | Carries | |---|---| | `data0.rgb` | The element's colour in linear HDR. | | `data1.x` | Seed that turns and re-sizes the petals; the shader adds a step every 1/30 s. |

# fxSpark A spark: a card turned onto its element's motion and stretched along it (`zero_billboard_streak`), drawn as a white-hot core fading to its colour at the rim and tapering to a point at both ends. The width across the streak follows `1 - along^2`, so the card is widest at its middle; pixels outside that width are discarded. The body carries the element's colour, and a white core is added on the axis, scaled by the colour's brightest channel (capped at 4) times 0.35. The result times `gain` is added to the frame. The combat graphs beside it in `combat/` draw with it as `fxSpark`, additive. The `impact` graph uses it for the sparks thrown back off the struck surface, the `muzzleFlash` graph for the burning powder streaking out of the bore, and the `tracer` graph for the round's white-hot streak and the embers it sheds. Each graph turns the particle onto its velocity, lengthens its Y scale, and colours it from an HDR ramp that cools over its life. The `bench_mixed` scene places all three graphs and the `main` scene places `muzzleFlash`. The shader includes `@builtin::shaderModules.billboard`. ## Properties | Property | Type | Default | Meaning | |---|---|---|---| | `gain` | float | 1.0 | Multiplies the output colour. | | `vertexBoundsDilation` | float | 0.3 | How far the vertex hook moves a vertex past the mesh, in world units: the culling bounds grow by it so a moved vertex stays inside them. | ## Lanes | Lane | Carries | |---|---| | `data0.rgb` | The element's colour in linear HDR. |

# effectShowcase The procedural effects of the Procgen Effects Showcase world. Each one is a `.procGraph` that plays through a `Generator`, and every shader, material and module a graph draws with sits beside it in this package, so the package carries everything its graphs need. Each graph's README says what it makes, how to place it and what each of its inputs changes. ## Contents | Folder | Graphs | What they make | |---|---|---| | `combat/` | `impact`, `muzzleFlash`, `tracer` | A round striking a hard surface, the bloom at a barrel as a weapon fires, and the glowing streak of a round in flight. They draw with `fxFlash`, `fxSmoke` and `fxSpark` in `combat/shaders/`. | | `blast/` | `wall_blast` | A charge blowing a breach through a stone block wall, on a 9.6 s loop. | | `storm/` | `storm`, `tower` | A thunderstorm around a lone tower: wind-driven rain, lightning striking on the schedule `schedule.module` keeps, and sparks and smoke where strikes land. `tower` is the stone keep it stands around. | | `rift/` | `arcane_rift` | A rift tearing open in the ground, its motes and rubble moved by the compute shaders in `rift/compute/`. | | `dragon/` | `dragon_breath` | A dragon's fire breath sweeping a courtyard: a flame jet, rolling smoke and drifting embers. | | `launch/` | `launch` | A heavy-lift rocket liftoff on one looping timeline, with the heat-haze material `rk_haze_mat`. | | `waterfall/` | `wf_env`, `wf_water`, `wf_spray`, `wf_foam`, `wf_mist` | A waterfall built in parts: the cliff, basin and boulders, the falling and still water, the droplets, the foam where the falls land, and the mist with its rainbow. Its water materials are in `waterfall/materials/`. | | `shaders/` | | `fx_noise`, the noise functions the waterfall and wall blast shaders include. | ## Playing one A graph plays on a `Generator` component bound to it: ```lua -- `graph` is the graph's reference: the AssetRef `asset.resolve` or a search returns for it. local e = entity.spawn("impact", { position = { 0, 1, 0 } }) e.component.add("Generator", { graph = graph, playOn = "load" }) ``` Set a graph's inputs with the Generator's `params`, e.g. `params = { size = 3 }`.