Helpers and Renderers

Helpers & Renderers

A grab-bag of static helpers in Helpers/ and a renderer base in Renderers/, shared across the family so you don't rebuild rotation math, particle/sound catalogues, inventory counting or fluid surfaces inline. Everything here is reusable from a consuming mod.

ExOrientation - rotation math

Single source of truth for horizontal rotation. Use these instead of hand-rolled angle switches.

public static class ExOrientation
{
    public static int AngleFromSide(string? side);                 // north 0, west 90, south 180, east 270
    public static Vec3i RotateOffset(Vec3i off, int angle);        // rotate a structure-local offset (Y untouched)
    public static Vec3i RotateOffset(int x, int y, int z, int angle);
    public static BlockPos GlobalPos(BlockPos origin, int localX, int localY, int localZ, int angle);
    public static Vec3i ReadOffset(JsonObject? node, Vec3i fallback);     // read { x, y, z } from JSON
    public static Vec3d ReadOffsetD(JsonObject? node, Vec3d fallback);    // double-precision (particle anchors)
    public static BlockPos WorldPosFromAttr(BlockPos origin, JsonObject? node, Vec3i fallback, int angle);
    public static Cuboidf[] RotateBoxes(Cuboidf[] boxes, int angle);     // rotate collision/selection boxes around centre
    public static BlockFacing RotateFacing(BlockFacing baseFace, int angle);
    public static void RotateAroundCenter(ref float x, ref float z, int angle, float center = 0.5f);
}

WorldPosFromAttr is the canonical "JSON offset -> world position": origin + RotateOffset(ReadOffset(node), angle). RotateBoxes returns copies (unchanged for angle 0), so cache the result rather than recomputing each frame. AllowedOrientations-style lookups should likewise be cached props.

ExParticles - particle catalogue

Named colour presets plus a configurable core and high-level effect helpers - don't build SimpleParticleProperties inline.

public static class ExParticles
{
    // Colour presets (int ARGB):
    public static readonly int Vapor, Exhaust, GasLeakTint, Water, Smoke, GlowSpark, Dust, AirTint;

    public static void Spawn(IWorldAccessor world, int color, Vec3d minPos, Vec3d maxPos,
        Vec3f minVelocity, Vec3f maxVelocity, float minQuantity, float maxQuantity,
        float lifeLength, float gravityEffect, float minSize, float maxSize,
        EnumParticleModel model = EnumParticleModel.Quad,
        EvolvingNatFloat? opacityEvolve = null, EvolvingNatFloat? sizeEvolve = null,
        bool shouldDieInLiquid = false);

    public static Vec3d FaceCenter(BlockPos pos, BlockFacing face);
    public static Vec3f OutVel(BlockFacing face, float speed, float spread);
    public static int? GasColor(string gasType, bool ventAir = true);

    // High-level effects:
    public static void RisingPlume(/* box bounds + timing */);
    public static void ChimneySmoke(IWorldAccessor world, BlockPos chimneyPos, string gasType);
    public static void SteamPlume(IWorldAccessor world, BlockPos cell, int count);
    public static void SteamPuff(IWorldAccessor world, Vec3d pos, int count);
    public static void AirInhale(IWorldAccessor world, Vec3d mouth, int count);
    public static void SmokeCloud(IWorldAccessor world, Vec3d pos, int count);
    public static void GasLeak(IWorldAccessor world, BlockPos pos, BlockFacing face, float intensity = 1f);
    public static void GasVent(IWorldAccessor world, BlockPos pos, BlockFacing face, string gasType);
    public static void WaterJet(IWorldAccessor world, BlockPos pos, BlockFacing face, float intensity = 1f);
    public static void WaterSpill(IWorldAccessor world, BlockPos cell);
    public static void FallingDust(IWorldAccessor world, BlockPos pos);
}

ExSounds - sound catalogue

AssetLocation constants for every sound the family reuses (many repurposed vanilla sounds), plus play helpers with the side-gating done right.

public static class ExSounds
{
    // Constants (AssetLocation), grouped: molten/heat (Sizzle, MoltenMetal, PourMetal, Embers, Fire,
    // Extinguish, Ignite), mechanical (Latch, Bellows, Ingot, AnvilHit, Build, StoneCrush, ToggleSwitch,
    // CokeOvenDoorOpen/Close, ...), fluids/venting (SmallSplash, WaterPour, Watering, ExtinguishHiss),
    // steam ambience (Cooking, Lava, Creek, MetalGrinding, Swoosh, PlanetaryGears, *Explosion, ...).

    public static void Play(ICoreAPI? api, BlockPos pos, AssetLocation sound, float volume = 1f, float range = 24f);  // server only
    public static void PlayThrottled(ICoreAPI? api, BlockPos pos, AssetLocation sound, ref long lastMs, long intervalMs, float volume = 1f, float range = 24f);
    public static void PlayLocal(IWorldAccessor world, BlockPos pos, AssetLocation sound, float volume = 1f, float range = 16f, bool randomizePitch = true);  // client-safe, no side gate
    public static void PlayLoop(IWorldAccessor world, BlockPos pos, AssetLocation sound, ref long lastMs, long intervalMs, float volume = 1f, float range = 16f);  // client-safe
    public static void PlayAt(IWorldAccessor world, BlockPos pos, AssetLocation sound, IPlayer? byPlayer = null, bool randomizePitch = true, float range = 32f, float volume = 1f);
    public static void PlayChance(IWorldAccessor world, BlockPos pos, AssetLocation sound, double chance, bool randomizePitch = true, float range = 32f, float volume = 1f);
    public static ILoadedSound? CreateLoop(ICoreAPI? api, BlockPos pos, AssetLocation sound, float volume = 1f, float range = 16f, float pitch = 1f);  // client only, gapless loop
    public static void SplashSound(IWorldAccessor world, BlockPos pos);   // quiet splash ~30% of the time
    public static void HissSound(IWorldAccessor world, BlockPos pos);     // soft steam/gas hiss ~30% of the time
}

Play* (server) vs PlayLocal/PlayLoop (no side gate, client-safe) is the distinction to get right; CreateLoop returns the ILoadedSound for you to start/stop/dispose.

ExInventory - counting & consuming items

public static class ExInventory
{
    public static int Count(IPlayer player, Func<ItemStack, bool> matches);            // all inventories
    public static int Take(IPlayer player, Func<ItemStack, bool> matches, int quantity);
    public static int CountHotbar(IPlayer player, Func<ItemStack, bool> matches);      // hotbar only
    public static int TakeHotbar(IPlayer player, Func<ItemStack, bool> matches, int quantity);
}

Take/TakeHotbar remove up to quantity matching items and return how many were actually taken

• useful for machine build/operation costs.

ExItems, ExCreativeTabs, ExBlockNames

public static class ExItems
{
    public static ItemStack[] WrenchStacks(IWorldAccessor world);   // one stack per registered wrench, cached, for interaction help
}

public static class ExCreativeTabs
{
    public static void EnsureTab(string tabCode);   // append a custom creative tab (reflection; no-op if internal type absent)
}

public static class ExBlockNames
{
    public static string Decorate(Block block, string baseName);    // append material/rock/brick variant + refractory tier
}

ExContentGate - disabling content

Config-gated "turn this content off": hide collectibles from creative + handbook and strip their recipes. Each method returns how many it affected.

public static class ExContentGate
{
    public static int HideFromCreativeAndHandbook(ICoreAPI api, Func<CollectibleObject, bool> match);
    public static int RemoveClayformingRecipes(ICoreAPI api, Func<AssetLocation, bool> outputMatch);
    public static int RemoveGridRecipes(ICoreAPI api, Func<AssetLocation, bool> outputMatch);
}

Clearing a block's creative tabs and stacks also removes it from the handbook, so HideFromCreativeAndHandbook does both. Pair it with a config toggle for "disable X" features (e.g. smex tool-mold gating behind /exmod molds).

SurfaceRenderer - flat fluid surfaces

Renderers/SurfaceRenderer is an IRenderer base for drawing a flat, textured horizontal surface (a liquid line) inside a block - water tanks, molten canals. It owns the quad geometry built from footprint boxes and the standard-shader plumbing; subclasses supply tint, height and texture.

public abstract class SurfaceRenderer : IRenderer
{
    protected SurfaceRenderer(BlockPos pos, ICoreClientAPI api, Cuboidf[] footprintBoxes, float rotationY, bool combine);

    public abstract double RenderOrder { get; }
    public virtual int RenderRange => 24;

    // Implement:
    protected abstract bool ShouldRender { get; }                     // draw this frame?
    protected abstract float SurfaceY { get; }                        // absolute surface height in block units
    protected abstract void ConfigureShader(IStandardShaderProgram shader, IRenderAPI render);  // tint/glow
    protected abstract bool BindSurfaceTexture(IRenderAPI render);    // bind texture; false to skip drawing

    // Optionally override:
    protected virtual int SelectMeshIndex() => 0;                     // which box-mesh to draw (combine == false)
    protected virtual bool UseBlend => false;                         // alpha blending for translucent surfaces

    public void OnRenderFrame(float deltaTime, EnumRenderStage stage);
    public virtual void Dispose();
}

combine: true merges all footprint boxes into one always-drawn mesh; combine: false keeps one mesh per box and lets SelectMeshIndex pick the cross-section by fill level.

Re-init on OnExchanged. rotationY is captured at construction. A wrench-rotated block renders its fluid surface in the pre-rotation orientation unless you rebuild the renderer in the block entity's OnExchanged. Surface glow is push-based, so a hot mold/tap/barrel also needs a client tick calling its update path or it freezes hot and snaps cold on interaction.

Related pages

• Multiblock Structures - ExOrientation drives SetStructureAngle.
• Config System - back ExContentGate toggles with a live config value.