Add player equipment, optional Curios/backpack drawers, and session drawer memory

build.gradle

@@ -25,6 +25,14 @@ repositories {
     mavenCentral()
     // JEI (optional integration; compile-time API only)
     maven { url = 'https://maven.blamejared.com' }
+    maven {
+        url = 'https://maven.theillusivec4.top/'
+        content { includeGroup 'top.theillusivec4.curios' }
+    }
+    maven {
+        url = 'https://api.modrinth.com/maven'
+        content { includeGroup 'maven.modrinth' }
+    }
 }
 
 // Dev-only runtime dependencies: on the runtime classpath, but kept out of the published POM.
@@ -34,6 +42,8 @@ configurations {
 }
 
 dependencies {
+    // Optional equipment discovery; neither bundled nor a transitive runtime requirement.
+    compileOnly "top.theillusivec4.curios:curios-neoforge:${curios_version}:api"
     // Optional JEI integration: compiled against the API only, never bundled or required.
     compileOnly "mezz.jei:jei-1.21.1-common-api:${jei_version}"
     compileOnly "mezz.jei:jei-1.21.1-neoforge-api:${jei_version}"
@@ -54,6 +64,13 @@ neoForge {
     runs {
         configureEach {
             gameDirectory = file('run')
+            // Optional user-level preferences apply only to manual development clients.
+            if (name in ['client', 'companionClient']) {
+                if (providers.gradleProperty('mmdlibClientWidth').isPresent())
+                    programArguments.addAll '--width', providers.gradleProperty('mmdlibClientWidth').get()
+                if (providers.gradleProperty('mmdlibClientHeight').isPresent())
+                    programArguments.addAll '--height', providers.gradleProperty('mmdlibClientHeight').get()
+            }
         }
         client {
             client()
@@ -92,6 +109,7 @@ tasks.named('processResources', ProcessResources) {
             neoforge_version_range: neoforge_version_range,
             loader_version_range: loader_version_range,
             jei_version_range: jei_version_range,
+            curios_version_range: curios_version_range,
             mod_id: mod_id,
             mod_name: mod_name,
             mod_license: mod_license,

docs/gui-screens.md

@@ -338,7 +338,7 @@ payload contains both lane index and state. The server restricts that selector t
 in its XML property. These settings persist with the machine. The graphical smoke run checks
 focus, typing, cancellation, resizing, view changes, release outside bounds and server rejection.
 
-The expanded menu protocol is version **2**, including a session token in menu-opening data.
+The expanded menu protocol is version **6**, including a session token in menu-opening data.
 Client and server must use matching MMDLib builds.
 
 ## Files and IDs
@@ -431,14 +431,26 @@ a compact meter, a few controls, an upgrade tab, and a side-configuration view:
 </screen>
 ```
 
-The standard player inventory (three rows of nine, a 4 px gap, then the hotbar) is added at the
-bottom automatically. Write `<player-inventory/>` only to place it somewhere else, or set
-`inventory="none"` on `<screen>` to leave it out.
+The standard player inventory is added at the bottom automatically: three rows of nine,
+a 4 px gap, then the hotbar. A column on the right contains helmet, chestplate, leggings and
+boots, with the offhand slot beside the hotbar. Empty equipment slots show vanilla icons;
+armor uses NeoForge's equipment checks, a one-item limit, and vanilla binding-curse protection.
+The complete inventory panel is 184 by 94 GUI pixels, including its toolbar row. There is no
+inventory label: the toolbar shares the helmet's row, directly above the three storage rows.
+Write `<player-inventory/>` only to place it somewhere else, or set `inventory="none"` on
+`<screen>` to leave out the inventory and equipment together.
+
+Shift-clicking equipment moves it into the ordinary inventory/hotbar. Machine outputs also
+go there; they do not automatically equip armor or fill the offhand. Shift-clicking ordinary
+inventory slots keeps the machine's `screenDestinations` routing. JEI recipe transfer uses
+only the ordinary inventory and hotbar, leaving equipped items alone.
 
 Optional `<inventory-controls>` goes after the main body and before tabs/popouts. Its button
 children form a right-aligned row above the player inventory (for example redstone and pause
 toggles). Automation's reusable `InventoryColorButtonBar` shares that row on the left, with
-scrollable overflow. The row is allocated once, and both sides align with the inventory edges.
+scrollable overflow. Both sides align with the nine-column storage grid, leaving the equipment
+column clear. Flat controls fit in the inventory's existing top row; taller controls add only
+the extra height they need.
 Use ordinary button declarations inside it; no spacer or coordinates are needed. This element
 requires a player inventory and is available to every screen, not just companion machines.
 
@@ -473,7 +485,9 @@ requires a player inventory and is available to every screen, not just companion
   - A button with `shows="<context>:<view>"` switches that context area to the view. Pressing
     it again, or the back button drawn in the corner of every non-default view, returns to the
     default view. Escape also returns to the default view first, then closes the screen.
-  - The area is sized to its largest view, so switching never moves the rest of the screen.
+  - The area measures the active view and fills the available width in vertical layouts.
+    Switching views resizes and recentres the panel, moving the inventory, toolbar and drawers
+    with it. Hidden settings do not reserve empty space; menu slot identities stay unchanged.
   - A view's `title` is drawn at its top, so the player can always tell which view is showing.
   - The shown view is remembered per screen file for the session.
   - Slots in a hidden view exist on the server menu at all times, but are hidden and refuse
@@ -711,7 +725,9 @@ When JEI is installed:
   Pop-out tabs are 22×24 rectangles, coloured by kind: yellow information, amber warning,
   red error. Clicking one opens a matching drawer outward from that edge, with the icon
   retained on a darker rail as the close control. Its body is up to 150 pixels wide and
-  fits its text, capped at the main panel's bottom and the screen edge. Text wraps to the available width; scroll inside
+  fits its text. Info and inventory drawers share a 4-pixel inset from the main panel's top
+  and bottom, and stop earlier if the screen or an overlay limits the space. The side-config
+  drawer shares the top inset but can grow below the main panel to fit its filter controls. Text wraps to the available width; scroll inside
   to read longer content. Opening another drawer on the same edge replaces the open drawer;
   tabs remain visible and clickable on the rail.
 
@@ -724,6 +740,83 @@ When JEI is installed:
     sends a smeltable item to its ingredient slot and other fuel to its fuel slot. MMDLib only
     keeps slots in hidden views out of that routing.
 
+Drawer choices are remembered across MMDLib machine screens for the current connection.
+The left drawer (info, backpack or Curios) and right automation drawer are independent.
+Backpack selection uses its equipment slot address, and automation selection uses its resource
+group ID. Missing features are skipped; explicit closes are remembered. Joining another world
+or server resets these preferences. Filter-editor drafts are not carried between machines.
+
+## Equipped storage drawer (optional Curios integration)
+
+When Curios is installed, machine screens with a player inventory automatically show a
+bottom-left tab for an equipped item exposing NeoForge's `Capabilities.ItemHandler.ITEM`.
+The tab renders the actual item, including its model/tint components and custom name in
+the tooltip. No screen XML changes or backpack-specific API are needed.
+
+The server config `inventory.container_slots` selects functional Curios slots to inspect;
+the defaults are `back` and `backpack`. Cosmetic slots are excluded. Empty slots, ordinary
+items and zero-slot capabilities show no tab. Curios remains optional, and neither Curios
+nor any backpack mod is bundled with MMDLib.
+
+Click the tab to open storage on the left. Left/right clicks take a stack/half stack or
+insert the carried stack/one item. Shift-click a storage cell to move items into the player
+inventory; **while storage is open, shift-clicking the ordinary player inventory stores
+items in the selected container**. Machine-output and equipment transfers keep their usual
+behavior. Drag with the left button to divide the carried stack evenly, or with the right
+button to place one item in each visited slot. Drags starting in the backpack can include ordinary
+player inventory slots. Gestures starting in the normal inventory retain Minecraft's usual drag
+and double-click behavior. Press a configured hotbar key over a backpack slot to exchange its contents with that
+hotbar slot. Double-click a backpack stack to collect matching items from the entire selected backpack
+and ordinary player inventory, up to the carried item's stack limit. Item components,
+insertion/extraction restrictions and slot limits are respected. All transfers use only the
+container's insert/extract capability. A container may redirect insertions (for example,
+merging into existing stacks instead of the hovered empty slots), including during drags
+and hotbar swaps. Drag previews highlight backpack targets; final counts come from the container
+after release. The drawer does not bypass that behavior with direct slot setters.
+
+Backpack-specific upgrades/settings/crafting screens are not provided. Ordinary clicks with
+different carried items do not swap stacks; use a hotbar key for an explicit swap.
+
+Storage uses six slots per row inside a drawer filling the panel height between the shared
+4-pixel top and bottom insets, with the same tinted frame and
+darker icon rail as the other drawers. Large inventories are paged with the arrows or mouse wheel. Click the header to cycle
+between eligible equipped containers. The main panel stays stationary, opening storage
+closes a left information drawer, and the right automation drawer remains independent.
+If the window has insufficient space, the tab explains how to make room. Unequipping,
+replacing or resizing a container closes the drawer; stale clicks are rejected by the server.
+The drawer respects the capability's insertion/extraction filters and limits.
+
+Some items expose storage only after being initialized through their own normal UI. Such
+items show the tab only after initialization. The library does not initialize third-party
+storage or interpret its private data.
+
+For development, `runCompanionClient` and `runCompanionClientSmoke` include Curios,
+Sophisticated Backpacks and Sophisticated Core as runtime fixtures. Use
+`-PwithoutBackpacks` to omit them. These dependencies do not enter either published jar.
+Server GameTests run without these fixtures because Curios login sync requires a negotiated
+client connection; the client smoke test covers real backpack discovery and networked transfers.
+
+## Curios equipment drawer
+
+With Curios installed, screens that show player inventory also gain a **Curios** tab on
+the left. It sits above the backpack tab when an equipped container is available. The
+full-height drawer lists the player's visible Curios slot groups in their configured order,
+using Curios' names and empty-slot icons. The **E** column contains functional equipment;
+the **C** column contains cosmetic equipment where the slot type supports it. A dash means
+that slot has no cosmetic counterpart. Arrows and the mouse wheel page through longer lists.
+
+Left/right clicking equips or unequips through the actual Curios handlers. Shift-clicking
+an accessory moves it into ordinary player storage. While this drawer is open, shift-clicking
+player storage attempts to equip the item in a compatible **functional** slot; place cosmetic
+items directly in the cosmetic column. Existing equipment is not swapped automatically.
+Curios' validation, equip/unequip events and removal restrictions still apply.
+
+Opening this drawer closes backpack storage or the left information drawer; the right
+automation drawer remains independent. Escape closes the equipment drawer first. A change
+to the available slot groups or counts closes the old view and invalidates stale requests;
+reopening shows the updated slots. Curios stays optional, with no tab or class-loading
+requirement when absent. This drawer does not change slot definitions or rendering toggles.
+
 ## Proper use
 
 These are guidance for screen authors, not rules MMDLib can check:

docs/inventory-automation.md

@@ -20,10 +20,11 @@ on the left; inventory side configuration stays on the right. Filter controls oc
 scrollable region inside the configuration drawer below the addon slots. The arrow bar beneath
 the installed filter shows/hides this region; it has no duplicate selected-filter header.
 The drawer fits its
-visible controls and grows downward to fit an open filter, stopping four GUI pixels above the
-screen edge (with extra clearance for JEI's bottom toolbar when visible); overflow scrolls within
+visible controls and grows below the main panel as needed to fit an open filter, stopping at
+the screen margin or JEI toolbar limit; overflow scrolls within
 the filter region. The colour selector keeps its own compact
-height. Info drawers fit their text up to the main panel's bottom or the screen edge, whichever
+height. All drawers share the same frame renderer and four-pixel top inset. The configuration
+drawer can grow to the available screen height; inventory drawers retain the panel's bottom inset. Info drawers fit their text up to the inset bottom or the screen edge, whichever
 comes first.
 
 ## Define independent resource groups

docs/machine-companion.md

@@ -7,6 +7,12 @@ in `src/companion` and are packaged separately from the library.
 ## Play
 
 Run `./gradlew runCompanionClient`, create a creative world, and open the **MMDLib Machines** tab.
+
+For a personal window size, add `mmdlibClientWidth=2560` and `mmdlibClientHeight=1440` to
+`~/.gradle/gradle.properties` (or the file in your `GRADLE_USER_HOME`). These optional settings
+apply to `runClient` and `runCompanionClient` only and stay outside the repository. Without them,
+Minecraft uses its default window size. Automated smoke runs retain their own fixed dimensions.
+
 Place a **Creative Power Source** next to a machine, then right-click the machine to open its screen.
 The source supplies all six adjacent faces. JEI is included in development runs; add `-PwithoutJei`
 to run without it.

gradle.properties

@@ -31,6 +31,12 @@ parchment_mappings_version = 2024.11.17
 jei_version = 19.57.0.451
 jei_version_range = [19,)
 
+# Optional equipment API; backpack mods are companion runtime fixtures only.
+curios_version = 9.5.1+1.21.1
+curios_version_range = [9.5.1,10)
+sophisticated_backpacks_version = 1.21.1-3.26.20.2244
+sophisticated_core_version = 1.21.1-1.5.28.2458
+
 # Gradle
 org.gradle.jvmargs = -Xmx3G
 org.gradle.daemon = false

scripts/companion.gradle

@@ -7,10 +7,26 @@ sourceSets {
         compileClasspath += sourceSets.companion.output + sourceSets.companion.compileClasspath
         runtimeClasspath += sourceSets.companion.output + sourceSets.companion.runtimeClasspath
     }
+    // Mock GameTest connections cannot negotiate Curios' login-sync payloads.
+    // Reuse the compiled fixtures, but keep optional mods for real client/server smoke runs.
+    companionServerTest {
+        runtimeClasspath += sourceSets.companionTest.output + sourceSets.companion.output + sourceSets.main.output + sourceSets.main.runtimeClasspath
+    }
 }
 
 neoForge.addModdingDependenciesTo(sourceSets.companion)
 neoForge.addModdingDependenciesTo(sourceSets.companionTest)
+neoForge.addModdingDependenciesTo(sourceSets.companionServerTest)
+
+// Development fixtures only: do not add backpack APIs or required mod metadata to either jar.
+// -PwithoutBackpacks retains a companion run without Curios or backpack mods.
+if (!providers.gradleProperty('withoutBackpacks').isPresent()) {
+    dependencies {
+        companionRuntimeOnly "top.theillusivec4.curios:curios-neoforge:${curios_version}"
+        companionRuntimeOnly "maven.modrinth:sophisticated-backpacks:${sophisticated_backpacks_version}"
+        companionRuntimeOnly "maven.modrinth:sophisticated-core:${sophisticated_core_version}"
+    }
+}
 
 neoForge {
     mods {
@@ -40,7 +56,7 @@ neoForge {
         companionGameTestServer {
             type = 'gameTestServer'
             gameDirectory = layout.buildDirectory.dir('companion-gametest')
-            sourceSet = sourceSets.companionTest
+            sourceSet = sourceSets.companionServerTest
             loadedMods = [neoForge.mods.named(mod_id).get(), neoForge.mods.mmdlib_companion_test]
             systemProperty 'neoforge.enabledGameTestNamespaces', 'mmdlib_companion'
         }
@@ -69,7 +85,7 @@ tasks.matching { it.name == 'runCompanionClientSmoke' }.configureEach {
     doFirst {
         def smokeDir = layout.buildDirectory.dir('companion-client-smoke').get().asFile
         smokeDir.mkdirs()
-        new File(smokeDir, 'options.txt').text = 'guiScale:2\nmaxFps:30\nonboardAccessibility:false\n'
+        new File(smokeDir, 'options.txt').text = 'guiScale:2\nmaxFps:30\nonboardAccessibility:false\npauseOnLostFocus:false\n'
     }
     doLast {
         def log = layout.buildDirectory.file('companion-client-smoke/logs/latest.log').get().asFile
@@ -94,6 +110,13 @@ tasks.register('verifyCompanionPackaging') {
         new java.util.zip.ZipFile(tasks.named('jar').get().archiveFile.get().asFile).withCloseable { jar ->
             def leaked = jar.entries().findAll { it.name.contains('mmdlib_companion') || it.name.startsWith('zone/moddev/mc/companion/') }
             if (leaked) throw new GradleException('Companion content in MMDLib jar: ' + leaked*.name)
+            def bundledIntegrations = jar.entries().findAll { it.name.startsWith('top/theillusivec4/') || it.name.startsWith('net/p3pp3rf1y/') }
+            if (bundledIntegrations) throw new GradleException('Optional integration classes bundled in MMDLib: ' + bundledIntegrations*.name)
+            def metadata = jar.getInputStream(jar.getEntry('META-INF/neoforge.mods.toml')).getText('UTF-8')
+            if (!(metadata =~ /(?s)modId="curios"\s+type="optional"/).find())
+                throw new GradleException('Curios must be declared optional in the release jar')
+            if (metadata.contains('sophisticatedbackpacks') || metadata.contains('sophisticatedcore'))
+                throw new GradleException('Backpack test fixtures must not be dependencies of MMDLib')
         }
         new java.util.zip.ZipFile(companionJar.get().archiveFile.get().asFile).withCloseable { jar ->
             def leaked = jar.entries().findAll { it.name.startsWith('zone/moddev/mc/lib/') || it.name.startsWith('zone/moddev/mc/companion/test/') || it.name.contains('/structure/') }

scripts/gui-smoke.init.gradle

@@ -9,7 +9,7 @@ allprojects {
             def smokeDir = file(providers.gradleProperty('withoutJei').isPresent() ? 'build/gui-smoke-without-jei' : 'build/gui-smoke')
             smokeDir.mkdirs()
             new File(smokeDir, 'options.txt').text = 'guiScale:2\nmaxFps:30\nonboardAccessibility:false\n'
-            neoForge.runs.client.programArguments.addAll '--width', '1280', '--height', '960'
+            neoForge.runs.client.programArguments.set(['--width', '1280', '--height', '960'])
             neoForge.runs.client.gameDirectory = smokeDir
             neoForge.runs.client.systemProperty 'mmdlib.guiSmoke', 'true'
             tasks.configureEach { task ->