Add-ons: Color Effects — live exposure, desaturate and invert, apply as filter, panel

A built-in add-on in Effect › Color Effects and Object › Plug-ins › Color Effects:
- Exposure (stops of linear light, offset and gamma), Desaturate and
  Invert Colors as live colour adjustments, evaluated in stack order with
  those of Effect › Color Adjustments.
- addon.color.filter applies any colour adjustment to the colours
  themselves, through the Edit Colors pass, as one undo step.
- A panel picks an adjustment and its values, then adds it as a live
  effect or applies it as a filter.

The add-on lives in its own modules (effects, engine and ui-egui addons
folders) and leaves the existing effects, commands and menus as they
were.

crates/effects/src/addons.rs

@@ -0,0 +1,6 @@
+//! Effects of VectorCraft's built-in add-ons, one module per add-on.
+//!
+//! - [`color`]: Color Effects' live Exposure, Desaturate and Invert Colors, colour adjustments
+//!   evaluated with the others ([`crate::adjust`]).
+
+pub mod color;

crates/effects/src/addons/color.rs

@@ -0,0 +1,132 @@
+//! Color Effects (a built-in add-on): live Exposure, Desaturate and Invert Colors, in Effect › Color
+//! Effects. They are colour adjustments ([`crate::is_adjustment`]): they recolour what an object
+//! paints as the others do, in stack order with them.
+
+use serde_json::{Value, json};
+
+use crate::catalog::{EffectInfo, Lengths};
+use crate::util::num;
+
+/// Exposure: brighten or darken in stops of light, with an offset and a gamma.
+pub const EXPOSURE: &str = "addon.color.exposure";
+/// Desaturate: every colour to the grey of its lightness.
+pub const DESATURATE: &str = "addon.color.desaturate";
+/// Invert Colors: every colour to its RGB inverse.
+pub const INVERT: &str = "addon.color.invert";
+
+/// The add-on's effects, in menu order.
+pub const EFFECTS: [&str; 3] = [DESATURATE, EXPOSURE, INVERT];
+
+/// Is `id` one of the add-on's effects?
+pub fn is_color_effect(id: &str) -> bool {
+    EFFECTS.contains(&id)
+}
+
+/// The add-on's catalogue entries.
+pub(crate) fn catalog() -> Vec<EffectInfo> {
+    const MENU: &[&str] = &["Effect", "Color Effects"];
+    let e = |id, label, params, defaults| EffectInfo { id, label, menu: MENU, params, defaults, raster: false, lengths: Lengths::default() };
+    vec![
+        e(DESATURATE, "Desaturate", "{} turns every colour the object paints to the grey of its lightness (each colour keeps its model)", json!({})),
+        e(
+            EXPOSURE,
+            "Exposure…",
+            "{exposure: stops -20..20 (0; mostly the highlights: each stop doubles or halves the light), offset: -0.5..0.5 (0; lifts or sinks the shadows and midtones), gamma: 0.1..10 (1; above 1 lightens the midtones)} recolours as Brightness/Contrast does, in linear light",
+            json!({"exposure": 0.0, "offset": 0.0, "gamma": 1.0}),
+        ),
+        e(INVERT, "Invert Colors", "{} turns every colour the object paints to its RGB inverse (each colour keeps its model)", json!({})),
+    ]
+}
+
+/// One of the add-on's adjustments, its parameters normalised.
+#[derive(Clone, Debug, PartialEq)]
+pub(crate) enum Adjust {
+    /// Linear light times `gain`, plus `offset`, to the power 1 / `gamma`.
+    Exposure {
+        gain: f32,
+        offset: f32,
+        gamma: f32,
+    },
+    Desaturate,
+    Invert,
+}
+
+impl Adjust {
+    pub(crate) fn parse(id: &str, p: &Value) -> Option<Self> {
+        Some(match id {
+            EXPOSURE => Adjust::Exposure {
+                gain: 2f64.powf(num(p, "exposure", 0.0).clamp(-20.0, 20.0)) as f32,
+                offset: num(p, "offset", 0.0).clamp(-0.5, 0.5) as f32,
+                gamma: num(p, "gamma", 1.0).clamp(0.1, 10.0) as f32,
+            },
+            DESATURATE => Adjust::Desaturate,
+            INVERT => Adjust::Invert,
+            _ => return None,
+        })
+    }
+
+    pub(crate) fn apply(&self, rgb: [f32; 3]) -> [f32; 3] {
+        match self {
+            Adjust::Exposure { gain, offset, gamma } => rgb.map(|v| to_srgb((to_linear(v) * gain + offset).max(0.0).powf(1.0 / gamma))),
+            Adjust::Desaturate => {
+                let [r, g, b] = rgb;
+                [(r.max(g).max(b) + r.min(g).min(b)) / 2.0; 3]
+            }
+            Adjust::Invert => rgb.map(|v| 1.0 - v),
+        }
+    }
+}
+
+fn to_linear(v: f32) -> f32 {
+    let v = v.clamp(0.0, 1.0);
+    if v <= 0.04045 { v / 12.92 } else { ((v + 0.055) / 1.055).powf(2.4) }
+}
+
+fn to_srgb(v: f32) -> f32 {
+    let v = v.clamp(0.0, 1.0);
+    if v <= 0.003_130_8 { v * 12.92 } else { 1.055 * v.powf(1.0 / 2.4) - 0.055 }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::color_map;
+    use vectorcraft_doc::Effect;
+
+    fn map(id: &str, params: Value) -> crate::ColorMap {
+        color_map(&[Effect { id: id.into(), params, visible: true }]).unwrap()
+    }
+
+    fn close(a: [f32; 3], b: [f32; 3]) -> bool {
+        a.iter().zip(b).all(|(x, y)| (x - y).abs() < 0.01)
+    }
+
+    #[test]
+    fn the_effects_are_colour_adjustments_in_their_own_menu() {
+        for id in EFFECTS {
+            assert!(crate::is_adjustment(id), "{id}");
+            assert_eq!(crate::effect_info(id).unwrap().menu, ["Effect", "Color Effects"]);
+        }
+    }
+
+    #[test]
+    fn exposure_works_in_stops_of_linear_light() {
+        let grey = [0.5; 3];
+        assert!(close(map(EXPOSURE, json!({})).apply_rgb(grey), grey), "neutral by default");
+        // One stop doubles the light: sRGB 0.5 (linear 0.214) becomes linear 0.428, sRGB 0.686.
+        assert!(close(map(EXPOSURE, json!({"exposure": 1})).apply_rgb(grey), [0.686; 3]));
+        assert!(close(map(EXPOSURE, json!({"exposure": -20})).apply_rgb([1.0; 3]), [0.0; 3]));
+        assert!(map(EXPOSURE, json!({"offset": 0.1})).apply_rgb([0.0; 3])[0] > 0.3, "the offset lifts the shadows");
+        assert!(map(EXPOSURE, json!({"gamma": 2})).apply_rgb(grey)[0] > 0.6);
+        assert!(close(map(EXPOSURE, json!({"exposure": 1e300, "gamma": 0})).apply_rgb(grey), [1.0; 3]), "out of range values are clamped");
+    }
+
+    #[test]
+    fn desaturate_and_invert() {
+        assert!(close(map(DESATURATE, json!({})).apply_rgb([1.0, 0.0, 0.0]), [0.5; 3]));
+        assert!(close(map(DESATURATE, json!({})).apply_rgb([1.0, 1.0, 0.0]), [0.5; 3]), "lightness is kept, not luminance");
+        assert!(close(map(INVERT, json!({})).apply_rgb([1.0, 0.25, 0.0]), [0.0, 0.75, 1.0]));
+        let both = map(INVERT, json!({})).then(&map(INVERT, json!({})));
+        assert!(close(both.apply_rgb([0.2, 0.4, 0.6]), [0.2, 0.4, 0.6]));
+    }
+}

crates/effects/src/adjust.rs

@@ -27,7 +27,7 @@ pub const ADJUSTMENTS: [&str; 6] =
 
 /// Is `id` a colour adjustment effect?
 pub fn is_adjustment(id: &str) -> bool {
-    ADJUSTMENTS.contains(&id)
+    ADJUSTMENTS.contains(&id) || crate::addons::color::is_color_effect(id)
 }
 
 fn visible_adjustment(e: &Effect) -> bool {
@@ -88,6 +88,8 @@ enum Adjust {
     ShiftToColor { target: [f32; 3], amount: f32, preserve: bool },
     /// Warm/cool and magenta/green shifts, -1..1.
     TemperatureTint { temperature: f32, tint: f32 },
+    /// One of the Color Effects add-on's.
+    Addon(crate::addons::color::Adjust),
 }
 
 /// The colour adjustments of an effect list, composed in order.
@@ -175,7 +177,7 @@ impl Adjust {
                 preserve: flag(p, "preserveLightness", true),
             },
             "adjust.temperatureTint" => Adjust::TemperatureTint { temperature: amount(p, "temperature"), tint: amount(p, "tint") },
-            _ => return None,
+            _ => Adjust::Addon(crate::addons::color::Adjust::parse(id, p)?),
         })
     }
 
@@ -225,6 +227,7 @@ impl Adjust {
                 let (t, m) = (temperature * 0.3, tint * 0.3);
                 [r * (1.0 + t), g * (1.0 - m), b * (1.0 - t)]
             }
+            Adjust::Addon(a) => a.apply([r, g, b]),
         }
     }
 }

crates/effects/src/catalog.rs

@@ -791,6 +791,7 @@ pub fn effect_catalog() -> Vec<EffectInfo> {
             v.push(g(id, label, PATHFINDER, "{} (groups and layers: live Pathfinder over the members)", json!({})));
         }
     }
+    v.extend(crate::addons::color::catalog());
     v.push(g(TRAP, "Trap…", PATHFINDER, trap::EFFECT_PARAMS_DOC, trap::effect_defaults()));
     v.push(g(
         CROP_MARKS,

crates/effects/src/lib.rs

@@ -34,6 +34,7 @@
 //! anchored at the object's centre.
 #![forbid(unsafe_code)]
 
+pub mod addons;
 mod adjust;
 mod bake;
 mod clip;

crates/engine/src/cmd/addons.rs

@@ -2,10 +2,13 @@
 //! with commands under `addon.<name>.*` (see `docs/mcp.md`).
 
 mod cleanup;
+mod color;
 
 use super::CommandSpec;
 
 /// The commands of every built-in add-on.
 pub fn specs() -> Vec<CommandSpec> {
-    cleanup::specs()
+    let mut v = cleanup::specs();
+    v.extend(color::specs());
+    v
 }

crates/engine/src/cmd/addons/color.rs

@@ -0,0 +1,49 @@
+//! Color Effects (`addon.color.*`), a built-in add-on: its live effects (Exposure, Desaturate and
+//! Invert Colors, in Effect › Color Effects) are the effects crate's; here, Apply as Filter writes
+//! any colour adjustment into the colours themselves. Its panel and its submenu, Object › Plug-ins ›
+//! Color Effects, are the UI's.
+
+#[cfg(test)]
+mod tests;
+
+use serde_json::{Value, json};
+use vectorcraft_render::effects;
+
+use super::super::colorcmds::recolor;
+use super::super::{CommandSpec, bad, checked_ids_or_selection, cmd, has_selection, text_param};
+use crate::{Result, Session};
+
+pub fn specs() -> Vec<CommandSpec> {
+    vec![cmd!(
+        "addon.color.filter",
+        "Apply as Filter",
+        ["Object", "Plug-ins", "Color Effects"],
+        None,
+        "{effect: a colour adjustment's effect id (adjust.brightnessContrast, adjust.curves, adjust.hueSaturation, adjust.levels, adjust.shiftToColor, adjust.temperatureTint, addon.color.exposure, addon.color.desaturate or addon.color.invert), params?: {…} (as effect.apply; missing keys take the dialog defaults), fill?: true, stroke?: true, includeImages?: true, includePatterns?: true, ids?: [id…] (default: the selection)} recolour the objects and everything inside them as the live effect would draw them, but in their colours, as edit.colors.invert does (fills, strokes, type, gradient meshes, embedded images and pattern tiles), as one undo step; their effects stay → {changed}",
+        has_selection,
+        filter
+    )]
+}
+
+fn filter(s: &mut Session, p: &Value) -> Result<Value> {
+    const C: &str = "addon.color.filter";
+    let id = text_param(p, "effect", C)?.ok_or_else(|| bad(C, "missing `effect`"))?;
+    if !effects::is_adjustment(id) {
+        return Err(bad(C, format!("`{id}` is not a colour adjustment")));
+    }
+    let params = match p.get("params") {
+        None | Some(Value::Null) => json!({}),
+        Some(v @ Value::Object(_)) => v.clone(),
+        Some(_) => return Err(bad(C, "`params` must be an object")),
+    };
+    let fx = effects::new_effect(id, &params).ok_or_else(|| bad(C, format!("unknown effect `{id}`")))?;
+    let ids = checked_ids_or_selection(s, p, C)?;
+    // Settings that change nothing still make the pass, which then leaves every colour as it was.
+    let Some(map) = effects::color_map(&[fx]) else { return Ok(json!({ "changed": 0 })) };
+    let mut given = p.clone();
+    if let Some(o) = given.as_object_mut() {
+        o.insert("ids".into(), json!(ids.iter().map(|i| i.0).collect::<Vec<_>>()));
+    }
+    let label = effects::effect_info(id).map_or("Apply as Filter", |e| e.label.trim_end_matches('…'));
+    recolor(s, &given, label, &|c| map.apply(c))
+}

crates/engine/src/cmd/addons/color/tests.rs

@@ -0,0 +1,89 @@
+//! Color Effects: its live effects through effect.apply, and Apply as Filter.
+
+use serde_json::json;
+use vectorcraft_doc::NodeId;
+use vectorcraft_geom::Rect;
+
+use crate::Session;
+
+/// A document with a selected red rectangle, unstroked.
+fn red_rect() -> (Session, NodeId) {
+    let mut s = Session::new();
+    s.execute("file.new", &json!({"width": 200, "height": 200})).unwrap();
+    let id = NodeId(s.execute("shape.rectangle", &json!({"x": 20, "y": 20, "width": 60, "height": 60})).unwrap()["id"].as_u64().unwrap());
+    s.execute("paint.setFill", &json!({"color": "#ff0000"})).unwrap();
+    s.execute("paint.setStroke", &json!({"none": true})).unwrap();
+    (s, id)
+}
+
+fn fill_hex(s: &Session, id: NodeId) -> String {
+    s.doc().unwrap().doc.node(id).unwrap().appearance.fill_paint().color().unwrap().to_hex()
+}
+
+fn pixel(s: &Session) -> [u8; 4] {
+    vectorcraft_render::Renderer::new().render_region(&s.doc().unwrap().doc, Rect::new(0.0, 0.0, 100.0, 100.0), 1.0, true).pixel(50, 50)
+}
+
+#[test]
+fn the_live_effects_draw_without_changing_the_colours() {
+    for (effect, params, drawn) in [
+        ("addon.color.invert", json!({}), [0, 255, 255, 255]),
+        ("addon.color.desaturate", json!({}), [128, 128, 128, 255]),
+        ("addon.color.exposure", json!({"exposure": -20}), [0, 0, 0, 255]),
+    ] {
+        let (mut s, id) = red_rect();
+        s.execute("effect.apply", &json!({"effect": effect, "params": params})).unwrap();
+        assert_eq!(fill_hex(&s, id), "#ff0000", "{effect}");
+        assert_eq!(pixel(&s), drawn, "{effect}");
+    }
+}
+
+#[test]
+fn a_filter_recolours_the_object_as_one_undo_step() {
+    let (mut s, id) = red_rect();
+    let undo = s.doc().unwrap().history.undo.len();
+    let v = s.execute("addon.color.filter", &json!({"effect": "addon.color.invert"})).unwrap();
+    assert_eq!(v["changed"], 1);
+    assert_eq!(fill_hex(&s, id), "#00ffff");
+    let n = s.doc().unwrap().doc.node(id).unwrap().clone();
+    assert!(n.appearance.effects.is_empty(), "no effect is added");
+    assert_eq!(s.doc().unwrap().history.undo.len(), undo + 1);
+    s.execute("edit.undo", &json!({})).unwrap();
+    assert_eq!(fill_hex(&s, id), "#ff0000");
+}
+
+#[test]
+fn a_filter_takes_any_colour_adjustment_with_its_params() {
+    let (mut s, id) = red_rect();
+    s.execute("addon.color.filter", &json!({"effect": "adjust.hueSaturation", "params": {"hue": 120}})).unwrap();
+    assert_eq!(fill_hex(&s, id), "#00ff00");
+    // Live effects already on the object stay live, on top of the new colours.
+    s.execute("effect.apply", &json!({"effect": "addon.color.invert"})).unwrap();
+    s.execute("addon.color.filter", &json!({"effect": "addon.color.desaturate", "ids": [id.0]})).unwrap();
+    assert_eq!(fill_hex(&s, id), "#808080");
+    assert_eq!(s.doc().unwrap().doc.node(id).unwrap().appearance.effects.len(), 1);
+    // The stroke only: the fill stays.
+    s.execute("addon.color.filter", &json!({"effect": "addon.color.invert", "fill": false})).unwrap();
+    assert_eq!(fill_hex(&s, id), "#808080");
+}
+
+#[test]
+fn bad_requests_are_refused() {
+    let (mut s, id) = red_rect();
+    let undo = s.doc().unwrap().history.undo.len();
+    for p in [
+        json!({}),
+        json!({"effect": 3}),
+        json!({"effect": "distort.roughen"}),
+        json!({"effect": "adjust.nothing"}),
+        json!({"effect": "addon.color.invert", "params": [1]}),
+        json!({"effect": "addon.color.invert", "ids": [999_999]}),
+        json!({"effect": "addon.color.invert", "ids": ["x"]}),
+    ] {
+        assert!(s.execute("addon.color.filter", &p).is_err(), "{p}");
+    }
+    assert_eq!(fill_hex(&s, id), "#ff0000");
+    assert_eq!(s.doc().unwrap().history.undo.len(), undo);
+    s.execute("select.none", &json!({})).unwrap();
+    assert!(s.execute("addon.color.filter", &json!({"effect": "addon.color.invert"})).is_err(), "nothing selected");
+}

crates/ui-egui/src/addons.rs

@@ -2,10 +2,11 @@
 //! Object › Plug-ins, and acts through its engine commands (`addon.<name>.*`).
 
 pub mod cleanup;
+pub mod color;
 
 use crate::menus::Item;
 
 /// The add-ons' submenus, then a separator: the head of Object › Plug-ins.
 pub fn plugin_menu() -> Vec<Item> {
-    vec![Item::Sub("Artwork Cleanup", cleanup::menu()), Item::Sep]
+    vec![Item::Sub("Artwork Cleanup", cleanup::menu()), Item::Sub("Color Effects", color::menu()), Item::Sep]
 }

crates/ui-egui/src/addons/color.rs

@@ -0,0 +1,149 @@
+//! Color Effects' panel and submenu (Object › Plug-ins › Color Effects). The panel picks a colour
+//! adjustment and its values, then adds it to the selection as a live effect or applies it as a
+//! filter, into the colours themselves (`addon.color.filter`). The submenu applies the add-on's
+//! live effects (Effect › Color Effects has them too) and opens the panel.
+
+use egui::Ui;
+use serde_json::{Map, Value, json};
+
+use crate::VectorcraftApp;
+use crate::menus::Item;
+use crate::panels::{empty_state, pstate, set_pstate};
+use crate::widgets;
+
+/// The panel's id (`window.panel {panel: "colorEffects"}`).
+pub const ID: &str = "colorEffects";
+
+/// Where the panel keeps its choice and values (panel state).
+const STATE: &str = "color-effects";
+
+/// A value of an adjustment: (parameter, label, range, decimals, default).
+type Field = (&'static str, &'static str, (f64, f64), usize, f64);
+
+/// The adjustments the panel offers: (effect, label, values). Curves and Shift to Color, which take
+/// a curve or a colour, keep to their dialogs (Effect › Color Adjustments).
+const ADJUSTMENTS: [(&str, &str, &[Field]); 7] = [
+    (
+        "adjust.brightnessContrast",
+        "Brightness/Contrast",
+        &[("brightness", "Brightness", (-100.0, 100.0), 0, 0.0), ("contrast", "Contrast", (-100.0, 100.0), 0, 0.0)],
+    ),
+    (
+        "adjust.hueSaturation",
+        "Hue/Saturation",
+        &[
+            ("hue", "Hue", (-180.0, 180.0), 0, 0.0),
+            ("saturation", "Saturation", (-100.0, 100.0), 0, 0.0),
+            ("lightness", "Lightness", (-100.0, 100.0), 0, 0.0),
+        ],
+    ),
+    (
+        "adjust.levels",
+        "Levels",
+        &[
+            ("inputBlack", "Input Black", (0.0, 255.0), 0, 0.0),
+            ("inputWhite", "Input White", (0.0, 255.0), 0, 255.0),
+            ("gamma", "Gamma", (0.1, 10.0), 2, 1.0),
+            ("outputBlack", "Output Black", (0.0, 255.0), 0, 0.0),
+            ("outputWhite", "Output White", (0.0, 255.0), 0, 255.0),
+        ],
+    ),
+    (
+        "adjust.temperatureTint",
+        "Temperature/Tint",
+        &[("temperature", "Temperature", (-100.0, 100.0), 0, 0.0), ("tint", "Tint", (-100.0, 100.0), 0, 0.0)],
+    ),
+    (
+        "addon.color.exposure",
+        "Exposure",
+        &[("exposure", "Exposure", (-20.0, 20.0), 2, 0.0), ("offset", "Offset", (-0.5, 0.5), 3, 0.0), ("gamma", "Gamma", (0.1, 10.0), 2, 1.0)],
+    ),
+    ("addon.color.desaturate", "Desaturate", &[]),
+    ("addon.color.invert", "Invert Colors", &[]),
+];
+
+/// Adjustment `i` of [`ADJUSTMENTS`] (the first past the end).
+fn adjustment(i: usize) -> (&'static str, &'static str, &'static [Field]) {
+    ADJUSTMENTS.get(i).copied().unwrap_or(ADJUSTMENTS[0])
+}
+
+/// Object › Plug-ins › Color Effects.
+pub fn menu() -> Vec<Item> {
+    vec![
+        Item::Cmd("Color Effects Panel", "window.panel", json!({ "panel": ID })),
+        Item::Sep,
+        Item::Cmd("Exposure…", "effect.dialog", json!({ "effect": "addon.color.exposure" })),
+        Item::Cmd("Desaturate", "effect.apply", json!({ "effect": "addon.color.desaturate" })),
+        Item::Cmd("Invert Colors", "effect.apply", json!({ "effect": "addon.color.invert" })),
+    ]
+}
+
+/// The panel's choice and the values set for each adjustment.
+#[derive(Clone, Default)]
+struct Picked {
+    /// Index in [`ADJUSTMENTS`].
+    index: usize,
+    /// Values set, by effect id then parameter.
+    values: Map<String, Value>,
+}
+
+impl Picked {
+    /// The params of the adjustment picked: its values, the defaults where none is set.
+    fn params(&self) -> (&'static str, Value) {
+        let (id, _, fields) = adjustment(self.index);
+        let set = self.values.get(id).and_then(Value::as_object);
+        let p: Map<String, Value> =
+            fields.iter().map(|(k, _, _, _, default)| (k.to_string(), set.and_then(|m| m.get(*k)).cloned().unwrap_or(json!(default)))).collect();
+        (id, Value::Object(p))
+    }
+}
+
+pub fn show(app: &mut VectorcraftApp, ui: &mut Ui) {
+    if app.session.active().is_none_or(|d| d.selection.is_empty()) {
+        empty_state(ui, "sun", tl!("No selection"), tl!("Select objects to adjust their colors."));
+        return;
+    }
+    let mut st: Picked = pstate(ui.ctx(), STATE);
+    let labels: Vec<&str> = ADJUSTMENTS.iter().map(|a| a.1).collect();
+    let (id, label, fields) = adjustment(st.index);
+    const LABEL_W: f32 = 84.0;
+    widgets::label_row(ui, tl!("Adjustment"), LABEL_W, |ui| {
+        if let Some(i) = widgets::dropdown(ui, "color-effects-pick", label, &labels, 150.0) {
+            st.index = i;
+        }
+    });
+    let (_, params) = st.params();
+    for (key, name, (min, max), decimals, _) in fields {
+        let v = params.get(*key).and_then(Value::as_f64);
+        widgets::label_row(ui, tl!(name), LABEL_W, |ui| {
+            if let Some(n) = widgets::range_field(ui, ("color-effects", id, key), v, *min..=*max, "", *decimals, 70.0) {
+                let set = st.values.entry(id).or_insert_with(|| json!({}));
+                if let Some(m) = set.as_object_mut() {
+                    m.insert(key.to_string(), json!(n));
+                }
+            }
+        });
+    }
+    ui.add_space(4.0);
+    let (id, params) = st.params();
+    ui.horizontal(|ui| {
+        let run = |app: &mut VectorcraftApp, cmd: &str| {
+            if let Err(e) = app.run(cmd, json!({ "effect": id, "params": params })) {
+                app.status(e);
+            }
+        };
+        if widgets::flat_button(ui, tl!("Add as Effect"), 100.0).clicked() {
+            run(app, "effect.apply");
+        }
+        if widgets::flat_button(ui, tl!("Apply as Filter"), 100.0).clicked() {
+            run(app, "addon.color.filter");
+        }
+        if widgets::flat_button(ui, tl!("Reset"), 56.0).clicked() {
+            st.values.remove(id);
+        }
+    });
+    set_pstate(ui.ctx(), STATE, st);
+}
+
+#[cfg(test)]
+mod tests;

crates/ui-egui/src/addons/color/tests.rs

@@ -0,0 +1,61 @@
+use serde_json::json;
+use vectorcraft_engine::Session;
+
+use super::{ADJUSTMENTS, ID, Picked, STATE, show};
+use crate::panels::set_pstate;
+use crate::tests_labels::painted_text;
+use crate::{VectorcraftApp, menus};
+
+/// An app with a selected red rectangle.
+fn app() -> VectorcraftApp {
+    let mut app = VectorcraftApp::new(Session::new(), Default::default());
+    app.run("file.new", json!({"width": 200, "height": 200})).unwrap();
+    app.run("shape.rectangle", json!({"x": 10, "y": 10, "width": 40, "height": 40})).unwrap();
+    app.run("paint.setFill", json!({"color": "#ff0000"})).unwrap();
+    app
+}
+
+#[test]
+fn the_menus_list_the_effects_and_open_the_panel() {
+    let mut app = app();
+    let entries = menus::menu_entries(&app);
+    let at = |path: &[&str], label: &str| entries.iter().find(|e| e.path == path && e.label == label);
+    let plugins = ["Object", "Plug-ins", "Color Effects"];
+    let item = at(&plugins, "Color Effects Panel").expect("listed");
+    for label in ["Exposure…", "Desaturate", "Invert Colors"] {
+        assert!(at(&plugins, label).is_some(), "Object › Plug-ins › Color Effects › {label}");
+        assert!(at(&["Effect", "Color Effects"], label).is_some(), "Effect › Color Effects › {label}");
+    }
+    // The existing submenus are as they were.
+    assert!(at(&["Effect", "Color Adjustments"], "Exposure…").is_none());
+    menus::invoke(&mut app, "window.panel", item.params.clone());
+    assert!(crate::panel_docking::showing(&app.ui, ID), "the panel opens");
+}
+
+#[test]
+fn every_adjustment_offered_is_a_colour_adjustment_with_its_defaults() {
+    for (i, (id, _, fields)) in ADJUSTMENTS.iter().enumerate() {
+        assert!(vectorcraft_effects::is_adjustment(id), "{id}");
+        let defaults = vectorcraft_effects::effect_info(id).unwrap().defaults;
+        let (picked, params) = Picked { index: i, ..Picked::default() }.params();
+        assert_eq!(picked, *id);
+        for (key, ..) in fields.iter() {
+            assert_eq!(params[key], defaults[key], "{id} {key}");
+        }
+    }
+}
+
+#[test]
+fn the_panel_shows_the_values_and_its_buttons() {
+    let mut app = app();
+    let exposure = ADJUSTMENTS.iter().position(|a| a.0 == "addon.color.exposure").unwrap();
+    let text = painted_text(&mut app, |app, ui| {
+        set_pstate(ui.ctx(), STATE, Picked { index: exposure, ..Picked::default() });
+        show(app, ui);
+    });
+    for s in ["Exposure", "Offset", "Gamma", "Add as Effect", "Apply as Filter"] {
+        assert!(text.contains(s), "{s} in {text}");
+    }
+    app.run("select.none", json!({})).unwrap();
+    assert!(painted_text(&mut app, show).contains("No selection"));
+}

crates/ui-egui/src/dialogs/effect.rs

@@ -161,7 +161,8 @@ fn body(app: &mut VectorcraftApp, ui: &mut egui::Ui, d: &mut Dialog) -> bool {
     // Plug-in effects get fields from their parameter schema; colour adjustments their sliders.
     let changed = match vectorcraft_plugins::effect::installed(&id) {
         Some(plugin) => form::schema_fields(app, ui, d, plugin.manifest()),
-        None if vectorcraft_effects::is_adjustment(&id) => adjust_fields(ui, d),
+        // The Color Effects add-on's take the plain form of their parameters.
+        None if vectorcraft_effects::is_adjustment(&id) && !vectorcraft_effects::addons::color::is_color_effect(&id) => adjust_fields(ui, d),
         None if id == GLASS => glass_fields(app, ui, d, GLASS),
         None if id == TEXTURIZER => glass_fields(app, ui, d, TEXTURIZER),
         None if id == TRANSFORM => transform_fields(ui, d, app.session.general_unit()),

crates/ui-egui/src/i18n/bg.tsv

@@ -5637,3 +5637,20 @@ anchor	Points:	Точки:
 	Simplify Anchors (Keep Shape)	Опростяване на опорните точки (запазване на формата)
 	Deep Ungroup	Разгрупиране на всички нива
 	Rejoin Path Pieces	Повторно свързване на части от пътища
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Цветови ефекти
+	Color Effects Panel	Панел „Цветови ефекти“
+	Exposure	Експонация
+	Exposure…	Експонация…
+	Desaturate	Обезцветяване
+	Adjustment	Корекция
+	Add as Effect	Добавяне като ефект
+	Apply as Filter	Прилагане като филтър
+	Select objects to adjust their colors.	Изберете обекти, за да коригирате цветовете им.
+	Brightness/Contrast	Яркост/Контраст
+	Hue/Saturation	Оттенък/Наситеност
+	Temperature/Tint	Температура/Нюанс
+@msg	`{id}` is not a colour adjustment	`{id}` не е цветова корекция
+@msg	missing `effect`	липсва `effect`
+@msg	`params` must be an object	`params` трябва да бъде обект

crates/ui-egui/src/i18n/ca.tsv

@@ -5738,3 +5738,20 @@ anchor	Points:	Punts:
 	Simplify Anchors (Keep Shape)	Simplifica els punts d’ancoratge (mantén la forma)
 	Deep Ungroup	Desagrupa tots els nivells
 	Rejoin Path Pieces	Torna a unir els trossos de traçat
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Efectes de color
+	Color Effects Panel	Tauler Efectes de color
+	Exposure	Exposició
+	Exposure…	Exposició…
+	Desaturate	Dessaturar
+	Adjustment	Ajust
+	Add as Effect	Afegeix com a efecte
+	Apply as Filter	Aplica com a filtre
+	Select objects to adjust their colors.	Seleccioneu objectes per ajustar-ne els colors.
+	Brightness/Contrast	Lluentor/Contrast
+	Hue/Saturation	To/saturació
+	Temperature/Tint	Temperatura/To
+@msg	`{id}` is not a colour adjustment	`{id}` no és un ajust de color
+@msg	missing `effect`	falta `effect`
+@msg	`params` must be an object	`params` ha de ser un objecte

crates/ui-egui/src/i18n/cs.tsv

@@ -5747,3 +5747,20 @@ anchor	Points:	Body:
 	Simplify Anchors (Keep Shape)	Zjednodušit kotevní body (zachovat tvar)
 	Deep Ungroup	Oddělit všechny úrovně
 	Rejoin Path Pieces	Znovu spojit části cest
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Barevné efekty
+	Color Effects Panel	Panel Barevné efekty
+	Exposure	Expozice
+	Exposure…	Expozice…
+	Desaturate	Odbarvit
+	Adjustment	Úprava
+	Add as Effect	Přidat jako efekt
+	Apply as Filter	Použít jako filtr
+	Select objects to adjust their colors.	Vyberte objekty, jejichž barvy chcete upravit.
+	Brightness/Contrast	Jas/kontrast
+	Hue/Saturation	Odstín/sytost
+	Temperature/Tint	Teplota/nádech
+@msg	`{id}` is not a colour adjustment	`{id}` není úprava barev
+@msg	missing `effect`	chybí `effect`
+@msg	`params` must be an object	`params` musí být objekt

crates/ui-egui/src/i18n/da.tsv

@@ -5652,3 +5652,20 @@ anchor	Points:	Punkter:
 	Simplify Anchors (Keep Shape)	Forenkl ankerpunkter (bevar form)
 	Deep Ungroup	Afgruppér alle niveauer
 	Rejoin Path Pieces	Forbind kurvestykker igen
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Farveeffekter
+	Color Effects Panel	Panelet Farveeffekter
+	Exposure	Eksponering
+	Exposure…	Eksponering…
+	Desaturate	Afmæt
+	Adjustment	Justering
+	Add as Effect	Tilføj som effekt
+	Apply as Filter	Anvend som filter
+	Select objects to adjust their colors.	Markér objekter for at justere deres farver.
+	Brightness/Contrast	Lysstyrke/kontrast
+	Hue/Saturation	Farvetone/mætning
+	Temperature/Tint	Temperatur/toning
+@msg	`{id}` is not a colour adjustment	`{id}` er ikke en farvejustering
+@msg	missing `effect`	`effect` mangler
+@msg	`params` must be an object	`params` skal være et objekt

crates/ui-egui/src/i18n/de.tsv

@@ -5329,3 +5329,20 @@ anchor	Points:	Punkte:
 	Simplify Anchors (Keep Shape)	Ankerpunkte vereinfachen (Form erhalten)
 	Deep Ungroup	Alle Gruppierungsebenen aufheben
 	Rejoin Path Pieces	Pfadstücke wieder zusammenfügen
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Farbeffekte
+	Color Effects Panel	Farbeffekte-Bedienfeld
+	Exposure	Belichtung
+	Exposure…	Belichtung…
+	Desaturate	Sättigung verringern
+	Adjustment	Korrektur
+	Add as Effect	Als Effekt hinzufügen
+	Apply as Filter	Als Filter anwenden
+	Select objects to adjust their colors.	Wählen Sie Objekte aus, um ihre Farben anzupassen.
+	Brightness/Contrast	Helligkeit/Kontrast
+	Hue/Saturation	Farbton/Sättigung
+	Temperature/Tint	Temperatur/Farbstich
+@msg	`{id}` is not a colour adjustment	`{id}` ist keine Farbkorrektur
+@msg	missing `effect`	`effect` fehlt
+@msg	`params` must be an object	`params` muss ein Objekt sein

crates/ui-egui/src/i18n/el.tsv

@@ -5699,3 +5699,20 @@ anchor	Points:	Σημεία:
 	Simplify Anchors (Keep Shape)	Απλοποίηση σημείων αγκύρωσης (διατήρηση σχήματος)
 	Deep Ungroup	Κατάργηση ομαδοποίησης σε όλα τα επίπεδα
 	Rejoin Path Pieces	Επανένωση τμημάτων διαδρομών
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Εφέ χρώματος
+	Color Effects Panel	Πλαίσιο Εφέ χρώματος
+	Exposure	Έκθεση
+	Exposure…	Έκθεση…
+	Desaturate	Αποκορεσμός
+	Adjustment	Διόρθωση
+	Add as Effect	Προσθήκη ως εφέ
+	Apply as Filter	Εφαρμογή ως φίλτρο
+	Select objects to adjust their colors.	Επιλέξτε αντικείμενα για να προσαρμόσετε τα χρώματά τους.
+	Brightness/Contrast	Φωτεινότητα/Αντίθεση
+	Hue/Saturation	Απόχρωση/Κορεσμός
+	Temperature/Tint	Θερμοκρασία/Απόχρωση
+@msg	`{id}` is not a colour adjustment	Το `{id}` δεν είναι διόρθωση χρώματος
+@msg	missing `effect`	λείπει το `effect`
+@msg	`params` must be an object	Το `params` πρέπει να είναι αντικείμενο

crates/ui-egui/src/i18n/es.tsv

@@ -5689,3 +5689,20 @@ anchor	Points:	Puntos:
 	Simplify Anchors (Keep Shape)	Simplificar puntos de ancla (mantener forma)
 	Deep Ungroup	Desagrupar todos los niveles
 	Rejoin Path Pieces	Volver a unir fragmentos de trazado
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Efectos de color
+	Color Effects Panel	Panel Efectos de color
+	Exposure	Exposición
+	Exposure…	Exposición…
+	Desaturate	Desaturar
+	Adjustment	Ajuste
+	Add as Effect	Añadir como efecto
+	Apply as Filter	Aplicar como filtro
+	Select objects to adjust their colors.	Seleccione objetos para ajustar sus colores.
+	Brightness/Contrast	Brillo/contraste
+	Hue/Saturation	Tono/saturación
+	Temperature/Tint	Temperatura/tinte
+@msg	`{id}` is not a colour adjustment	`{id}` no es un ajuste de color
+@msg	missing `effect`	falta `effect`
+@msg	`params` must be an object	`params` debe ser un objeto

crates/ui-egui/src/i18n/fi.tsv

@@ -5778,3 +5778,20 @@ anchor	Points:	Pisteet:
 	Simplify Anchors (Keep Shape)	Yksinkertaista ankkuripisteet (säilytä muoto)
 	Deep Ungroup	Pura kaikki ryhmitystasot
 	Rejoin Path Pieces	Yhdistä polun palat uudelleen
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Väritehosteet
+	Color Effects Panel	Väritehosteet-paneeli
+	Exposure	Valotus
+	Exposure…	Valotus…
+	Desaturate	Poista värikylläisyys
+	Adjustment	Säätö
+	Add as Effect	Lisää tehosteena
+	Apply as Filter	Käytä suodattimena
+	Select objects to adjust their colors.	Valitse objektit, joiden värejä haluat säätää.
+	Brightness/Contrast	Kirkkaus/kontrasti
+	Hue/Saturation	Sävy/kylläisyys
+	Temperature/Tint	Lämpötila/sävy
+@msg	`{id}` is not a colour adjustment	`{id}` ei ole värisäätö
+@msg	missing `effect`	`effect` puuttuu
+@msg	`params` must be an object	`params` on oltava objekti

crates/ui-egui/src/i18n/fr.tsv

@@ -5746,3 +5746,20 @@ anchor	Points:	Points :
 	Simplify Anchors (Keep Shape)	Simplifier les points d’ancrage (conserver la forme)
 	Deep Ungroup	Dissocier tous les niveaux
 	Rejoin Path Pieces	Rejoindre les morceaux de tracé
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Effets de couleur
+	Color Effects Panel	Panneau Effets de couleur
+	Exposure	Exposition
+	Exposure…	Exposition…
+	Desaturate	Désaturer
+	Adjustment	Réglage
+	Add as Effect	Ajouter comme effet
+	Apply as Filter	Appliquer comme filtre
+	Select objects to adjust their colors.	Sélectionnez des objets pour régler leurs couleurs.
+	Brightness/Contrast	Luminosité/contraste
+	Hue/Saturation	Teinte/saturation
+	Temperature/Tint	Température/teinte
+@msg	`{id}` is not a colour adjustment	`{id}` n'est pas un réglage de couleur
+@msg	missing `effect`	`effect` manquant
+@msg	`params` must be an object	`params` doit être un objet

crates/ui-egui/src/i18n/hu.tsv

@@ -5733,3 +5733,20 @@ anchor	Points:	Pontok:
 	Simplify Anchors (Keep Shape)	Horgonypontok egyszerűsítése (alak megtartása)
 	Deep Ungroup	Csoportbontás minden szinten
 	Rejoin Path Pieces	Útvonaldarabok újraegyesítése
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Színeffektusok
+	Color Effects Panel	Színeffektusok panel
+	Exposure	Expozíció
+	Exposure…	Expozíció…
+	Desaturate	Telítettség csökkentése
+	Adjustment	Korrekció
+	Add as Effect	Hozzáadás effektusként
+	Apply as Filter	Alkalmazás szűrőként
+	Select objects to adjust their colors.	Jelöljön ki objektumokat a színeik módosításához.
+	Brightness/Contrast	Fényesség/kontraszt
+	Hue/Saturation	Színárnyalat/telítettség
+	Temperature/Tint	Színhőmérséklet/tónus
+@msg	`{id}` is not a colour adjustment	`{id}` nem színkorrekció
+@msg	missing `effect`	hiányzik: `effect`
+@msg	`params` must be an object	`params`: objektum kell

crates/ui-egui/src/i18n/id.tsv

@@ -5652,3 +5652,20 @@ anchor	Points:	Titik:
 	Simplify Anchors (Keep Shape)	Sederhanakan titik jangkar (pertahankan bentuk)
 	Deep Ungroup	Buka grup di semua tingkat
 	Rejoin Path Pieces	Sambungkan kembali potongan jalur
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Efek Warna
+	Color Effects Panel	Panel Efek Warna
+	Exposure	Eksposur
+	Exposure…	Eksposur…
+	Desaturate	Hilangkan Saturasi
+	Adjustment	Penyesuaian
+	Add as Effect	Tambahkan sebagai Efek
+	Apply as Filter	Terapkan sebagai Filter
+	Select objects to adjust their colors.	Pilih objek untuk menyesuaikan warnanya.
+	Brightness/Contrast	Kecerahan/kontras
+	Hue/Saturation	Rona/saturasi
+	Temperature/Tint	Suhu/tint
+@msg	`{id}` is not a colour adjustment	`{id}` bukan penyesuaian warna
+@msg	missing `effect`	`effect` tidak ada
+@msg	`params` must be an object	`params` harus berupa objek

crates/ui-egui/src/i18n/it.tsv

@@ -5363,3 +5363,20 @@ anchor	Points:	Punti:
 	Simplify Anchors (Keep Shape)	Semplifica punti di ancoraggio (mantieni forma)
 	Deep Ungroup	Separa tutti i livelli
 	Rejoin Path Pieces	Ricongiungi parti di tracciato
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Effetti colore
+	Color Effects Panel	Pannello Effetti colore
+	Exposure	Esposizione
+	Exposure…	Esposizione…
+	Desaturate	Desatura
+	Adjustment	Regolazione
+	Add as Effect	Aggiungi come effetto
+	Apply as Filter	Applica come filtro
+	Select objects to adjust their colors.	Seleziona gli oggetti per regolarne i colori.
+	Brightness/Contrast	Luminosità/contrasto
+	Hue/Saturation	Tonalità/saturazione
+	Temperature/Tint	Temperatura/tinta
+@msg	`{id}` is not a colour adjustment	`{id}` non è una regolazione del colore
+@msg	missing `effect`	manca `effect`
+@msg	`params` must be an object	`params` deve essere un oggetto

crates/ui-egui/src/i18n/ja.tsv

@@ -5432,3 +5432,20 @@ anchor	Points:	ポイント:
 	Simplify Anchors (Keep Shape)	アンカーポイントを単純化（形状を維持）
 	Deep Ungroup	すべての階層のグループ解除
 	Rejoin Path Pieces	パスの断片を再連結
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	カラー効果
+	Color Effects Panel	カラー効果パネル
+	Exposure	露光量
+	Exposure…	露光量…
+	Desaturate	彩度を下げる
+	Adjustment	補正
+	Add as Effect	効果として追加
+	Apply as Filter	フィルターとして適用
+	Select objects to adjust their colors.	カラーを補正するオブジェクトを選択してください。
+	Brightness/Contrast	明るさ・コントラスト
+	Hue/Saturation	色相・彩度
+	Temperature/Tint	色温度・色かぶり
+@msg	`{id}` is not a colour adjustment	`{id}` はカラー補正ではありません
+@msg	missing `effect`	`effect` が指定されていません
+@msg	`params` must be an object	`params` にはオブジェクトを指定してください

crates/ui-egui/src/i18n/ka.tsv

@@ -5736,3 +5736,20 @@ anchor	Points:	წერტილები:
 	Simplify Anchors (Keep Shape)	საყრდენი წერტილების გამარტივება (ფორმის შენარჩუნებით)
 	Deep Ungroup	დაჯგუფების მოხსნა ყველა დონეზე
 	Rejoin Path Pieces	ტრაექტორიის ნაწილების ხელახლა შეერთება
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	ფერის ეფექტები
+	Color Effects Panel	ფერის ეფექტების პანელი
+	Exposure	ექსპოზიცია
+	Exposure…	ექსპოზიცია…
+	Desaturate	გაუფერულება
+	Adjustment	კორექცია
+	Add as Effect	ეფექტად დამატება
+	Apply as Filter	ფილტრად გამოყენება
+	Select objects to adjust their colors.	აირჩიეთ ობიექტები მათი ფერების დასარეგულირებლად.
+	Brightness/Contrast	სიკაშკაშე/კონტრასტი
+	Hue/Saturation	ფერის ტონი/გაჯერება
+	Temperature/Tint	ტემპერატურა/ტონირება
+@msg	`{id}` is not a colour adjustment	`{id}` ფერის კორექცია არ არის
+@msg	missing `effect`	აკლია `effect`
+@msg	`params` must be an object	`params` უნდა იყოს ობიექტი

crates/ui-egui/src/i18n/ko.tsv

@@ -5326,3 +5326,20 @@ anchor	Points:	포인트:
 	Simplify Anchors (Keep Shape)	앵커 포인트 단순화(모양 유지)
 	Deep Ungroup	모든 단계 그룹 해제
 	Rejoin Path Pieces	패스 조각 다시 연결
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	색상 효과
+	Color Effects Panel	색상 효과 패널
+	Exposure	노출
+	Exposure…	노출…
+	Desaturate	채도 감소
+	Adjustment	조정
+	Add as Effect	효과로 추가
+	Apply as Filter	필터로 적용
+	Select objects to adjust their colors.	색상을 조정할 개체를 선택하십시오.
+	Brightness/Contrast	밝기/대비
+	Hue/Saturation	색조/채도
+	Temperature/Tint	색온도/색조
+@msg	`{id}` is not a colour adjustment	`{id}`은(는) 색상 조정이 아닙니다
+@msg	missing `effect`	`effect`이 없습니다
+@msg	`params` must be an object	`params`는 개체여야 합니다

crates/ui-egui/src/i18n/nl.tsv

@@ -5696,3 +5696,20 @@ anchor	Points:	Punten:
 	Simplify Anchors (Keep Shape)	Ankerpunten vereenvoudigen (vorm behouden)
 	Deep Ungroup	Alle groeperingsniveaus opheffen
 	Rejoin Path Pieces	Padstukken opnieuw verbinden
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Kleureffecten
+	Color Effects Panel	Deelvenster Kleureffecten
+	Exposure	Belichting
+	Exposure…	Belichting…
+	Desaturate	Desatureren
+	Adjustment	Aanpassing
+	Add as Effect	Toevoegen als effect
+	Apply as Filter	Toepassen als filter
+	Select objects to adjust their colors.	Selecteer objecten om hun kleuren aan te passen.
+	Brightness/Contrast	Helderheid/contrast
+	Hue/Saturation	Kleurtoon/verzadiging
+	Temperature/Tint	Temperatuur/tint
+@msg	`{id}` is not a colour adjustment	`{id}` is geen kleuraanpassing
+@msg	missing `effect`	`effect` ontbreekt
+@msg	`params` must be an object	`params` moet een object zijn

crates/ui-egui/src/i18n/pl.tsv

@@ -5601,3 +5601,20 @@ anchor	Points:	Punkty:
 	Simplify Anchors (Keep Shape)	Uprość punkty kontrolne (zachowaj kształt)
 	Deep Ungroup	Rozgrupuj wszystkie poziomy
 	Rejoin Path Pieces	Ponownie połącz fragmenty ścieżek
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Efekty koloru
+	Color Effects Panel	Panel Efekty koloru
+	Exposure	Ekspozycja
+	Exposure…	Ekspozycja…
+	Desaturate	Usuń nasycenie
+	Adjustment	Korekta
+	Add as Effect	Dodaj jako efekt
+	Apply as Filter	Zastosuj jako filtr
+	Select objects to adjust their colors.	Zaznacz obiekty, aby skorygować ich kolory.
+	Brightness/Contrast	Jasność/kontrast
+	Hue/Saturation	Barwa/nasycenie
+	Temperature/Tint	Temperatura/odcień
+@msg	`{id}` is not a colour adjustment	`{id}` nie jest korektą koloru
+@msg	missing `effect`	brak `effect`
+@msg	`params` must be an object	`params` musi być obiektem

crates/ui-egui/src/i18n/pt-br.tsv

@@ -5664,3 +5664,20 @@ anchor	Points:	Pontos:
 	Simplify Anchors (Keep Shape)	Simplificar Pontos de Ancoragem (Manter Forma)
 	Deep Ungroup	Desagrupar Todos os Níveis
 	Rejoin Path Pieces	Reunir Partes de Caminho
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Efeitos de cor
+	Color Effects Panel	Painel Efeitos de cor
+	Exposure	Exposição
+	Exposure…	Exposição…
+	Desaturate	Dessaturar
+	Adjustment	Ajuste
+	Add as Effect	Adicionar como efeito
+	Apply as Filter	Aplicar como filtro
+	Select objects to adjust their colors.	Selecione objetos para ajustar suas cores.
+	Brightness/Contrast	Brilho/Contraste
+	Hue/Saturation	Matiz/Saturação
+	Temperature/Tint	Temperatura/Tom
+@msg	`{id}` is not a colour adjustment	`{id}` não é um ajuste de cor
+@msg	missing `effect`	falta `effect`
+@msg	`params` must be an object	`params` deve ser um objeto

crates/ui-egui/src/i18n/ru.tsv

@@ -5725,3 +5725,20 @@ anchor	Points:	Точки:
 	Simplify Anchors (Keep Shape)	Упростить опорные точки (сохранить форму)
 	Deep Ungroup	Разгруппировать все уровни
 	Rejoin Path Pieces	Соединить части контуров
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Цветовые эффекты
+	Color Effects Panel	Панель «Цветовые эффекты»
+	Exposure	Экспозиция
+	Exposure…	Экспозиция…
+	Desaturate	Обесцветить
+	Adjustment	Коррекция
+	Add as Effect	Добавить как эффект
+	Apply as Filter	Применить как фильтр
+	Select objects to adjust their colors.	Выделите объекты, чтобы настроить их цвета.
+	Brightness/Contrast	Яркость/контраст
+	Hue/Saturation	Оттенок/насыщенность
+	Temperature/Tint	Температура/оттенок
+@msg	`{id}` is not a colour adjustment	`{id}` не является цветокоррекцией
+@msg	missing `effect`	отсутствует `effect`
+@msg	`params` must be an object	`params` должно быть объектом

crates/ui-egui/src/i18n/sv.tsv

@@ -5771,3 +5771,20 @@ anchor	Points:	Punkter:
 	Simplify Anchors (Keep Shape)	Förenkla ankarpunkter (behåll formen)
 	Deep Ungroup	Dela upp grupper på alla nivåer
 	Rejoin Path Pieces	Foga samman banbitar igen
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Färgeffekter
+	Color Effects Panel	Panelen Färgeffekter
+	Exposure	Exponering
+	Exposure…	Exponering…
+	Desaturate	Avmätta
+	Adjustment	Justering
+	Add as Effect	Lägg till som effekt
+	Apply as Filter	Använd som filter
+	Select objects to adjust their colors.	Markera objekt för att justera deras färger.
+	Brightness/Contrast	Ljusstyrka/kontrast
+	Hue/Saturation	Nyans/mättnad
+	Temperature/Tint	Temperatur/färgton
+@msg	`{id}` is not a colour adjustment	`{id}` är ingen färgjustering
+@msg	missing `effect`	`effect` saknas
+@msg	`params` must be an object	`params` måste vara ett objekt

crates/ui-egui/src/i18n/tr.tsv

@@ -5705,3 +5705,20 @@ anchor	Points:	Noktalar:
 	Simplify Anchors (Keep Shape)	Bağlantı Noktalarını Basitleştir (Şekli Koru)
 	Deep Ungroup	Tüm Düzeylerde Grubu Çöz
 	Rejoin Path Pieces	Yol Parçalarını Yeniden Birleştir
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Renk Efektleri
+	Color Effects Panel	Renk Efektleri Paneli
+	Exposure	Pozlama
+	Exposure…	Pozlama…
+	Desaturate	Doygunluğu Kaldır
+	Adjustment	Ayar
+	Add as Effect	Efekt Olarak Ekle
+	Apply as Filter	Filtre Olarak Uygula
+	Select objects to adjust their colors.	Renklerini ayarlamak için nesneleri seçin.
+	Brightness/Contrast	Parlaklık/Kontrast
+	Hue/Saturation	Ton/Doygunluk
+	Temperature/Tint	Sıcaklık/Renk Tonu
+@msg	`{id}` is not a colour adjustment	`{id}` bir renk ayarı değil
+@msg	missing `effect`	"isim" eksik
+@msg	`params` must be an object	"gradyan" bir nesne olmalıdır

crates/ui-egui/src/i18n/uk.tsv

@@ -5343,3 +5343,20 @@ anchor	Points:	Точки:
 	Simplify Anchors (Keep Shape)	Спростити опорні точки (зберегти форму)
 	Deep Ungroup	Розгрупувати всі рівні
 	Rejoin Path Pieces	З’єднати частини контурів
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Колірні ефекти
+	Color Effects Panel	Панель «Колірні ефекти»
+	Exposure	Експозиція
+	Exposure…	Експозиція…
+	Desaturate	Знебарвити
+	Adjustment	Корекція
+	Add as Effect	Додати як ефект
+	Apply as Filter	Застосувати як фільтр
+	Select objects to adjust their colors.	Виділіть об’єкти, щоб налаштувати їхні кольори.
+	Brightness/Contrast	Яскравість/контраст
+	Hue/Saturation	Відтінок/насиченість
+	Temperature/Tint	Температура/відтінок
+@msg	`{id}` is not a colour adjustment	`{id}` не є корекцією кольору
+@msg	missing `effect`	відсутня `effect`
+@msg	`params` must be an object	`params` має бути об’єктом

crates/ui-egui/src/i18n/vi.tsv

@@ -5345,3 +5345,20 @@ anchor	Points:	Điểm:
 	Simplify Anchors (Keep Shape)	Đơn giản hóa điểm neo (giữ hình dạng)
 	Deep Ungroup	Bỏ nhóm mọi cấp
 	Rejoin Path Pieces	Nối lại các mảnh đường dẫn
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	Hiệu ứng màu
+	Color Effects Panel	Bảng Hiệu ứng màu
+	Exposure	Phơi sáng
+	Exposure…	Phơi sáng…
+	Desaturate	Khử bão hòa
+	Adjustment	Điều chỉnh
+	Add as Effect	Thêm làm hiệu ứng
+	Apply as Filter	Áp dụng làm bộ lọc
+	Select objects to adjust their colors.	Chọn đối tượng để điều chỉnh màu của chúng.
+	Brightness/Contrast	Độ sáng/Tương phản
+	Hue/Saturation	Sắc độ/Độ bão hòa
+	Temperature/Tint	Nhiệt độ màu/Tông
+@msg	`{id}` is not a colour adjustment	`{id}` không phải là điều chỉnh màu
+@msg	missing `effect`	thiếu `effect`
+@msg	`params` must be an object	`params` phải là một đối tượng

crates/ui-egui/src/i18n/zh-hans.tsv

@@ -5586,3 +5586,20 @@ anchor	Points:	点：
 	Simplify Anchors (Keep Shape)	简化锚点（保持形状）
 	Deep Ungroup	取消所有层级编组
 	Rejoin Path Pieces	重新连接路径片段
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	颜色效果
+	Color Effects Panel	颜色效果面板
+	Exposure	曝光度
+	Exposure…	曝光度…
+	Desaturate	去色
+	Adjustment	调整
+	Add as Effect	添加为效果
+	Apply as Filter	作为滤镜应用
+	Select objects to adjust their colors.	选择对象以调整其颜色。
+	Brightness/Contrast	亮度/对比
+	Hue/Saturation	色相/饱和度
+	Temperature/Tint	色温/色调
+@msg	`{id}` is not a colour adjustment	`{id}` 不是颜色调整
+@msg	missing `effect`	缺少 `effect`
+@msg	`params` must be an object	`params` 必须是对象

crates/ui-egui/src/i18n/zh-hant.tsv

@@ -5382,3 +5382,20 @@ anchor	Points:	點：
 	Simplify Anchors (Keep Shape)	簡化錨點（保持形狀）
 	Deep Ungroup	解散所有層級群組
 	Rejoin Path Pieces	重新連接路徑片段
+
+# Color Effects add-on (Object › Plug-ins › Color Effects, Effect › Color Effects): its effects, panel and messages.
+	Color Effects	顏色效果
+	Color Effects Panel	顏色效果面板
+	Exposure	曝光度
+	Exposure…	曝光度…
+	Desaturate	去除飽和度
+	Adjustment	調整
+	Add as Effect	加入為效果
+	Apply as Filter	套用為濾鏡
+	Select objects to adjust their colors.	選取物件以調整其顏色。
+	Brightness/Contrast	亮度/對比
+	Hue/Saturation	色相/飽和度
+	Temperature/Tint	色溫/色調
+@msg	`{id}` is not a colour adjustment	`{id}` 不是顏色調整
+@msg	missing `effect`	未提供 `effect`
+@msg	`params` must be an object	`params` 必須是物件

crates/ui-egui/src/menus/submenus.rs

@@ -134,6 +134,7 @@ pub(super) fn effect_menu() -> Vec<Item> {
     let order = [
         "3D and Materials",
         "Color Adjustments",
+        "Color Effects",
         "Convert to Shape",
         "Crop Marks",
         "Distort & Transform",

crates/ui-egui/src/panels.rs

@@ -180,6 +180,7 @@ pub fn show_icon_panel(app: &mut VectorcraftApp, ui: &mut Ui, id: &str) {
         asset_export::ID => asset_export::show(app, ui),
         css_properties::ID => css_properties::show(app, ui),
         crate::addons::cleanup::ID => crate::addons::cleanup::show(app, ui),
+        crate::addons::color::ID => crate::addons::color::show(app, ui),
         id if library_panel::parse(id).is_some() => library_panel::show(app, ui, id),
         _ => {
             dim_label(ui, tl!("This panel is on the roadmap (see the parity plan)."));

crates/ui-egui/src/state.rs

@@ -198,6 +198,7 @@ pub const ICON_PANELS: &[(&str, &str, &str)] = &[
     (crate::panels::css_properties::ID, "CSS Properties", "globe"),
     (crate::panels::variables::ID, "Variables", "chart-column"),
     (crate::addons::cleanup::ID, "Artwork Cleanup", "sparkles"),
+    (crate::addons::color::ID, "Color Effects", "sun"),
 ];
 
 /// Groups of icon panels separated by dividers in the collapsed column.

docs/mcp.md

@@ -5708,3 +5708,31 @@ topmost piece.
 {"name":"run_command","arguments":{"command":"addon.cleanup.fix","params":{"kinds":["strayPoints","needlessGroups"]}}}
 {"name":"run_command","arguments":{"command":"addon.cleanup.simplify","params":{"tolerance":40,"protectCorners":true}}}
 ```
+
+## Color Effects add-on
+
+Color Effects is a built-in add-on: its effects are colour adjustments in Effect › Color Effects, its command is
+`addon.color.filter`, and in the desktop app it also lives in Object › Plug-ins › Color Effects and in its panel
+(`window.panel {panel: "colorEffects"}`).
+
+Its live effects go on through `effect.apply` like any other and recolour what the object paints, in stack order with
+the other colour adjustments (Effect › Color Adjustments); each colour keeps its colour model:
+
+| Effect | Parameters | Does |
+|---|---|---|
+| `addon.color.exposure` (Exposure…) | `exposure` stops −20…20 (0), `offset` −0.5…0.5 (0), `gamma` 0.1…10 (1) | Scales the light in linear light (each stop doubles or halves it, mostly in the highlights), adds the offset (shadows and midtones) and applies the gamma |
+| `addon.color.desaturate` (Desaturate) | none | Turns every colour to the grey of its lightness |
+| `addon.color.invert` (Invert Colors) | none | Turns every colour to its RGB inverse |
+
+`addon.color.filter {effect, params?, fill?, stroke?, includeImages?, includePatterns?, ids?}` applies any colour
+adjustment, the add-on's or one of Effect › Color Adjustments', to the colours themselves instead of as a live effect:
+fills, strokes, type, gradient meshes, embedded images and pattern tiles, as `edit.colors.invert` reaches them, as one
+undo step. Missing `params` take the effect's dialog defaults; the objects' own effects stay as they are.
+
+```json
+{"name":"run_command","arguments":{"command":"effect.apply","params":{"effect":"addon.color.exposure","params":{"exposure":1.5}}}}
+{"name":"run_command","arguments":{"command":"addon.color.filter","params":{"effect":"adjust.hueSaturation","params":{"hue":120}}}}
+```
+
+The panel picks an adjustment (Brightness/Contrast, Hue/Saturation, Levels, Temperature/Tint, Exposure, Desaturate or
+Invert Colors), sets its values, and then Add as Effect (`effect.apply`) or Apply as Filter (`addon.color.filter`).

docs/target-app-parity.md

@@ -1,6 +1,6 @@
 # Parity with Adobe Illustrator
 
-> **Last reviewed:** 2026-10-10 · **Last updated:** 2026-10-30 · **Change:** minor (Artwork Cleanup, a built-in add-on beyond Illustrator; scores unchanged) · **Target:** Adobe Illustrator 2026 (30.x; public release notes through 30.7, August 2026)
+> **Last reviewed:** 2026-10-10 · **Last updated:** 2026-10-30 · **Change:** minor (Color Effects, a built-in add-on beyond Illustrator; scores unchanged) · **Target:** Adobe Illustrator 2026 (30.x; public release notes through 30.7, August 2026)
 
 ## Feature submission evidence
 
@@ -1216,10 +1216,22 @@ Show, Fix Selected and Fix All (each one undo step), Deep Ungroup and Rejoin Pat
 alone; Fix All as one step; scopes; rejoin within the gap only) and `addons::cleanup::tests` in `vectorcraft-ui-egui`
 (the submenu opens the panel; Check lists what it finds). Commands: `docs/mcp.md` › Artwork Cleanup add-on.
 
+## Color Effects add-on (2026-10-30)
+
+A VectorCraft addition, not an Illustrator feature, so no area score moves. Effect › Color Effects adds live Exposure
+(stops of linear light, offset and gamma), Desaturate and Invert Colors as colour adjustments evaluated with those of
+Effect › Color Adjustments (`vectorcraft_effects::addons::color`), and `addon.color.filter` applies any colour adjustment
+to the colours themselves through the Edit Colors pass. Object › Plug-ins › Color Effects and its panel reach them.
+Tests: `addons::color` in `vectorcraft-effects` (exposure in stops, desaturate keeps lightness, invert twice is
+identity), `cmd::addons::color::tests` in `vectorcraft-engine` (drawn live without changing the colours; a filter as one
+undo step, with any adjustment and its params; bad requests refused) and `addons::color::tests` in
+`vectorcraft-ui-egui` (the menus and the panel). Commands: `docs/mcp.md` › Color Effects add-on.
+
 ## Revision history
 
 | Date | Change | Summary |
 |---|---|---|
+| 2026-10-30 | minor | Color Effects, a built-in add-on beyond Illustrator; scores and estimates unchanged |
 | 2026-10-30 | minor | Artwork Cleanup add-on (a VectorCraft addition): evidence added; scores unchanged. |
 | 2026-10-30 | minor | Hardware: a second finger cancels the tool press the first finger began, and a finger landing while another is down presses nothing, so a pinch only navigates (#4198); evidence added; scores unchanged (estimated). |
 | 2026-10-30 | minor | File formats: SVG export writes axis-aligned rectangles as `<rect>`, circles and ellipses as `<circle>`/`<ellipse>`, straight lines as `<line>` and other straight-segment paths as `<polygon>`/`<polyline>`, keeping `<path>` where a shape element would draw differently (#4652); evidence added; scores and hours unchanged (estimated). |

docs/ui-parity.md

@@ -1,6 +1,6 @@
 # UI and interaction parity
 
-> **Last reviewed:** 2026-10-10 · **Last updated:** 2026-10-30 · **Change:** minor (Artwork Cleanup add-on: its panel and Object › Plug-ins submenu; scores unchanged) · **Target:** Adobe Illustrator 2026 (30.x)
+> **Last reviewed:** 2026-10-10 · **Last updated:** 2026-10-30 · **Change:** minor (Color Effects add-on: its effects, panel and Object › Plug-ins submenu; scores unchanged) · **Target:** Adobe Illustrator 2026 (30.x)
 
 ## Feature submission evidence
 
@@ -322,6 +322,7 @@ next unit in the order a right-click on a ruler lists them, from Feet back to Po
 | Tabs panel: a stop drags from where the press landed, a stop just added included | done | #1458 |
 | Outline view keeps template layers in Preview, dimmed | done | #1486; a picture placed to be traced stays visible under the outlines |
 | Artwork Cleanup add-on (VectorCraft addition): Object › Plug-ins › Artwork Cleanup opens its panel, which checks the selection or the document for 16 kinds of issue, lists them with counts, and shows or fixes the picked rows or all of them, each fix one undo step; Simplify Anchors (Keep Shape), Rejoin Path Pieces and Deep Ungroup open their options first | done | `addon.cleanup.*`, `crates/ui-egui/src/addons/cleanup.rs` and its tests; not an Illustrator feature, so it is not scored |
+| Color Effects add-on (VectorCraft addition): live Exposure, Desaturate and Invert Colors in Effect › Color Effects and Object › Plug-ins › Color Effects; its panel picks a colour adjustment and its values and adds it as a live effect or applies it as a filter, into the colours, as one undo step | done | `addon.color.*`, `crates/ui-egui/src/addons/color.rs` and its tests; not an Illustrator feature, so it is not scored |
 
 ## Look and feel
 
@@ -362,6 +363,7 @@ separate. Scores and hours unchanged. [Behavior and command details](development
 
 | Date | Change | Summary |
 |---|---|---|
+| 2026-10-30 | minor | Color Effects add-on: its effects, panel and Object › Plug-ins submenu; scores and estimates unchanged |
 | 2026-10-30 | minor | Artwork Cleanup add-on (a VectorCraft addition): its panel and Object › Plug-ins › Artwork Cleanup; scores and estimates unchanged |
 | 2026-10-30 | minor | Spinners: a held arrow repeats after a pause (#4267); scores and estimates unchanged |
 | 2026-10-30 | minor | Control bar: a Replace menu swaps the selected symbol instances' symbol (#4121); scores and estimates unchanged |