# FrameVR Online Campus Building Basics More information to come regarding accessibility and usability design activities. Visit [https://codex.immersivelrn.org/books/conference-online-hosts-private/chapter/ilrn-2026-framevr-campus-design-project](https://codex.immersivelrn.org/books/online-hosts-ilrn2026-private/chapter/ilrn-2026-framevr-campus-design-project) for the Google Sheet handling Campus Construction for iLRN 2026 \*Requires access, private shelf, email [volunteers@immersivelrn.org](volunteers@immersivelrn.org) for access. # Debugging & Performance [![Debugging Option_1.png](https://codex.immersivelrn.org/uploads/images/gallery/2026-03/scaled-1680-/h7lqlxOGTeUs2igD-debugging-option-1.png)](https://codex.immersivelrn.org/uploads/images/gallery/2026-03/h7lqlxOGTeUs2igD-debugging-option-1.png) To view the performance in greater depth (beyond what is built into the regular FrameVR menu), add ?debug=true to the end of any FrameVR URL. Once you have done this and refreshed, you will have the option to "Open Inspector," which will show you a panel with various options to help you understand how well the frame is performing in terms of draw calls and more. [![Debugging Option_2.png](https://codex.immersivelrn.org/uploads/images/gallery/2026-03/scaled-1680-/esvCblExCB5ogAZW-debugging-option-2.png)](https://codex.immersivelrn.org/uploads/images/gallery/2026-03/esvCblExCB5ogAZW-debugging-option-2.png) # About Building in FrameVR + Advanced Interactions # FrameVR Technical Capabilities *iLRN Campus Codex — Engine, interactivity, and 3D asset support* ## Under the Hood: Babylon.js FrameVR is built on [Babylon.js](https://www.babylonjs.com/), a powerful open-source 3D rendering engine. However, FrameVR abstracts most of Babylon.js’s native functionality behind its own interface. Users work within FrameVR’s sandbox rather than having direct access to the full engine. Advanced features such as complex physics simulations and custom scripting are not directly accessible within the platform. Teams should work within the Action Editor and supported asset formats to achieve interactivity. ## FrameVR Knowledge Base & Other Info FrameVR offers many valuable resources for users building on their platform. Here are a few of the options available: [**Knowledge Base**](https://support.framevr.io/Frame-Knowledge-Base-cfc4bc81aa1442a9a2dd9e995dbaeab0) [**Blog**](https://learn.framevr.io/blog) [**Tutorials**](https://learn.framevr.io/tutorials) [**Help Forum (Discord)**](https://discord.com/invite/5m5hBrV) [**Developer API**](https://api.framevr.io/doc/automate/) ## Interactivity: The Action Editor FrameVR’s Action Editor provides a no-code interface for adding interactivity to spaces. While limited compared to full engine access, it supports a meaningful range of triggers and responses: • **Play Audio —** Trigger ambient sounds, narration, or sound effects on proximity or interaction • **Animate Models —** Activate animation cycles embedded in uploaded 3D assets • **Show / Hide Objects —** Toggle visibility of elements based on user actions • **Open URLs —** Link out to external content, documents, or media • **Teleport Users —** Move participants to different locations within or between spaces These tools are well-suited for guided experiences, interactive exhibits, and layered storytelling within a campus environment. **Access this tool by entering Edit Mode > Click Asset > Open Action Editor > Set Trigger + Action** [![ActionEdit2.png](https://codex.immersivelrn.org/uploads/images/gallery/2026-03/scaled-1680-/dPtWZdmhqAcTmnxA-actionedit2.png)](https://codex.immersivelrn.org/uploads/images/gallery/2026-03/dPtWZdmhqAcTmnxA-actionedit2.png) [![ActionEdit1.png](https://codex.immersivelrn.org/uploads/images/gallery/2026-03/scaled-1680-/2ShpyN9KTxop2PBg-actionedit1.png)](https://codex.immersivelrn.org/uploads/images/gallery/2026-03/2ShpyN9KTxop2PBg-actionedit1.png) [![ActionEdit3.png](https://codex.immersivelrn.org/uploads/images/gallery/2026-03/scaled-1680-/P8J0Zr3uBIWt7enP-actionedit3.png)](https://codex.immersivelrn.org/uploads/images/gallery/2026-03/P8J0Zr3uBIWt7enP-actionedit3.png) ## 3D Assets: glTF Format FrameVR supports [glTF (.glb/.gltf)](https://en.wikipedia.org/wiki/GlTF), the widely used open standard for 3D assets. Importantly, glTF files can contain embedded animation cycles, which can then be triggered via the Action Editor — making it possible to bring in animated objects (moving parts, characters, environmental effects) without custom code. Recommended tools for creating or converting glTF assets: • **Blender** (free, open-source) — excellent glTF export with full animation support • **Sketchfab** — browse and download community glTF models, many with embedded animations ( low poly items and Museum-specific [https://sketchfab.com/members?segment=organization%2Fmuseum&sort\_by=-followerCount](https://sketchfab.com/members?segment=organization%2Fmuseum&sort_by=-followerCount) ) • Various online converters for existing 3D models ## Gaussian Splats: Photorealistic Spatial Capture FrameVR supports Gaussian Splat files (.ply / .splat), a cutting-edge format for representing real-world spaces with photorealistic quality. Gaussian Splats are captured using photogrammetry-adjacent workflows and rendered as volumetric point clouds, producing immersive, high-fidelity representations of physical locations. This is a significant capability for campus-building — real landmarks, architectural spaces, or culturally significant sites can be captured and placed directly into a FrameVR environment. Capture tools to explore: • **Luma AI** — mobile-friendly capture, accessible for most devices • **Polycam** — supports Gaussian Splat export alongside standard photogrammetry • **Postshot** — desktop processing for higher-quality splat results \[DRAFT: Example soon, check back for update! \] **Note: **A Gaussian Splat of a nearby landmark is being explored as a demonstration asset for the iLRN campus — a model for how regional teams might contribute place-based content to shared virtual spaces. # Using Scenes in FrameVR **iLRN 2026 Virtual Campus — Codex** **Using Scenes in FrameVR** *Draft Areas, Alternate Configurations & Advanced Scene Management* **Last Updated:** *April 10, 2026* | **Maintained by:** *Charlene Hardin* **Codex Section:** FrameVR Build Documentation **What Are Scenes?** Scenes are one of FrameVR’s most useful but least understood features. At its simplest, a Scene is a saved state of your Frame — everything in it, where it is, and how it’s configured. A single Frame can have multiple Scenes, and you can switch between them instantly. Think of Scenes like different “slides” of the same room. The Frame URL stays the same, but the contents of the space can change completely depending on which Scene is active. Visitors always enter whichever Scene is currently set as the active one. **Why This Matters for Building** When you’re actively developing a Frame, you don’t always want your work-in-progress visible to everyone who walks in. Scenes solve this by letting you maintain a “live” version of the space while building and experimenting in a separate draft state — all within the same Frame URL. This means you can iterate freely without worrying about visitors stumbling into half-finished layouts, test new asset placements without disrupting the live experience, and preserve a clean baseline you can always return to. **Common Uses** • **Draft mode** — Build and test new layouts or assets in a Scene without affecting what visitors see when they arrive • **Event configuration** — Set up a Scene specifically for a live session (with a presenter screen, specific seating arrangement, etc.) and switch back to the standard configuration afterward • **Preservation** — Save a clean baseline Scene before making major changes, so you can always revert if something goes wrong • **Seasonal or programming variation** — Configure different Scenes for different activities within the same Branch House without needing separate Frame URLs **How to Create and Switch Scenes**
![](https://codex.immersivelrn.org/uploads/images/gallery/2026-04/rIOmSWn2P5bWzAIO-embedded-image-ivkadi2p.png)
![](https://codex.immersivelrn.org/uploads/images/gallery/2026-04/mJOo08gIKNU1WHtt-embedded-image-1yasbabi.png)
**Important: What Carries Across All Scenes** Not everything is Scene-specific. Certain elements are persistent across all Scenes in a Frame regardless of which Scene is active.
**Watch out: Built-in Web Browsers** The built-in web browser is one of the most notable persistent elements — if you have a browser open or configured in your Frame, it will be visible and active in every Scene. Keep this in mind when planning your layout, particularly if you’re using a browser for a specific event or presentation and don’t want it to appear in your standard visitor-facing Scene.
As a general rule: if you’re unsure whether an element is Scene-specific, test it in a draft Scene before relying on it in a live configuration. For more information, always consult [FrameVR’s Knowledgebase.](https://support.framevr.io/Frame-Knowledge-Base-cfc4bc81aa1442a9a2dd9e995dbaeab0) **Things to Know** • The Scene that loads by default when someone enters your Frame URL is whichever Scene is currently set as active • Switching Scenes affects all visitors currently in the Frame — coordinate with your team before switching during a live event • Asset budgets apply across your whole Frame, not per Scene — a heavily loaded draft Scene still counts toward your performance limits even if it isn’t the active one **Recommended Practice for iLRN Builders** Keep at least two Scenes in any Frame you are actively developing:
**LIVE** The current visitor-facing version. This is what people see when they enter the Frame. Only update this Scene when changes are ready to go live.
**DRAFT** Your active working area. Build, test, and experiment here freely. Keep this Scene clearly named so anyone with build access knows not to set it as active by mistake.
Name your Scenes clearly and consistently. Avoid generic names like “Scene 1” or “Scene 2” — use descriptive labels that make the purpose immediately obvious to any team member who opens the Frame settings. **Advanced Features** **Triggering Scene Changes with the Editing Panel** This opens possibilities for guided experiences, event transitions, and interactive storytelling within a single Frame. A persistent navigation element that appears in all Scenes and triggers transitions between them is one practical application.
![](https://codex.immersivelrn.org/uploads/images/gallery/2026-04/363kb2XfCR3JitTS-embedded-image-o1ghksgj.png)
**Setting Items to Appear Across Multiple Scenes** By default, assets you place in a Frame are associated with the Scene you’re working in. However, when editing an individual item, you can configure it to appear in multiple Scenes simultaneously. This is useful for elements that should be consistent across several configurations — like permanent signage, a logo, navigation buttons, or a welcome poster — without having to duplicate them manually in each Scene.
![](https://codex.immersivelrn.org/uploads/images/gallery/2026-04/KMWaWMiDLH6xAuI8-embedded-image-i1d5vgab.png)
**Quick Reference**
**Question** **Answer**
**Does the Frame URL change between Scenes?** No. The Frame URL stays the same regardless of which Scene is active.
**Can visitors switch Scenes themselves?** Only if you set up an Action Editor trigger they can interact with. Otherwise only admins/builders can switch Scenes.
**Do asset budgets apply per Scene?** No. Budgets apply to the whole Frame. All Scenes count toward your total.
**Are web browsers Scene-specific?** No. Built-in web browsers are persistent across all Scenes.
**Can I make an asset appear in multiple Scenes?** Yes. Edit the item and set it to appear in whichever Scenes you choose.
Questions or corrections? Contact the iLRN build team via Discord or the Codex discussion thread. # iLRN 2026 Virtual Campus Canva Projects - Infrastructure **iLRN 2026 Virtual Campus** **Canva Project Architecture** *Working document — Charlene Hardin, Volunteer Coordinator & Campus Builder • April 2026* SPREADSHEET CONTAINING LINKS TO CANVA: [https://docs.google.com/spreadsheets/d/1dTTy6wOXBb71phRYVhTxZ6nOpveb-wEbZyVvq216lCQ/edit?gid=0#gid=0](https://docs.google.com/spreadsheets/d/1dTTy6wOXBb71phRYVhTxZ6nOpveb-wEbZyVvq216lCQ/edit?gid=0#gid=0) # Purpose This document defines the Canva project structure for iLRN 2026 campus infrastructure assets. Projects are organised by output type, not by room, so that all assets of a given type share consistent dimensions, brand settings, and naming conventions regardless of which volunteer produces them. Dimensions in this document are working assumptions derived from in-world measurement of existing FrameVR frames and are subject to revision following in-world testing. # 1. Canva Projects Four projects cover all current infrastructure asset types:
**Project Name** **Canvas Size** **Aspect Ratio** **Asset Type**
Wayfinding Banners 1920 × 320 px 6:1 Overhead/corridor ID strips
Large Boards 2560 × 1024 px 5:2 Main wall display / presentations
Square Posters 1080 × 1080 px 1:1 Branch House artwork, general posters
Buttons & Icons 512 × 512 px 1:1 Nav buttons, GOTO menu identifiers
*⚠ Dimensions are working assumptions from in-world screenshots, April 2026. Confirm via in-world testing before producing large batches.* # 2. Project Setup in Canva When creating each project in the iLRN 2026 Greece workspace:
**Setup checklist for each new Canva project** 1. Create project with the exact pixel dimensions from the table above (Custom size). 2. Name the project using the convention: iLRN2026\_\[AssetType\] — e.g. iLRN2026\_WayfindingBanners 3. Apply brand colours as Canva colour palette swatches (manual entry — Brand Kit admin access pending). 4. Add Cinzel, Raleway, and Lato as project fonts. 5. Name each page within the project by room or context — e.g. House01\_Foundations, House02\_Assessment. 6. Do not use Canva's background remover or AI image tools without checking output against brand guidelines.
*⚠ Jonathon holds admin access to the Canva Brand Kit. Until the Brand Kit is populated, colours and fonts must be set manually per project. Flag this to Jonathon.* # 3. File Naming Convention All assets exported from Canva and uploaded to FrameVR must follow this naming convention. This keeps the campus spreadsheet, Codex pages, and FrameVR asset libraries reconcilable.
**Field** **Convention** **Example**
Project prefix iLRN2026\_ iLRN2026\_
Asset type Banner / Board / Poster / Button / Icon Banner\_
Room/context House01 through House10, or context name House02\_
Descriptor Brief description, no spaces WayfindingStrip
Full example — iLRN2026\_Banner\_House02\_WayfindingStrip
For presenter content placed in Branch Houses via the Tally opt-in form, the existing convention applies: FirstInitialLastName\_PaperFirstTwoWords Infrastructure assets (produced by Team A or Canva Champions) use the iLRN2026\_ prefix convention above to distinguish them from presenter content. # 4. Brand Reference Apply these values consistently across all Canva projects. Do not use Canva's default palette or theme colours.
**Element** **Value** **Notes**
Primary \#1B3B6F — Aegean Deep Backgrounds, headers, text on light
Secondary \#36BAE7 — Athens Cyan Accents, highlights
Accent \#E07840 — Agora Orange Calls to action, warnings, emphasis
Display font Cinzel Titles only — decorative
Heading font Raleway Section headers, labels
Body font Lato All body copy, captions
*⚠ The Brand Kit lives in the 2026 Greece Canva workspace but requires Jonathon's admin access to populate fully. Until then, enter hex values manually.* # 5. Performance Rules FrameVR performance is the constraint that governs all asset decisions. The April 10 real-world test demonstrated that 19 uncompressed images dropped average FPS from 60 to 10. Every image uploaded to a Frame must go through the compression pipeline below.
**Rule** **Detail**
Compress before upload All images must be processed through squoosh.app before uploading to FrameVR
2K texture ceiling Maximum 2048px on longest side for mobile iOS compatibility
Format Export from Canva as PNG; compress via squoosh to WebP or optimised PNG
File size target Under 500KB per image after compression where possible
No smoke/particles Do not design assets that imply particle effects in-world
*✓ Design at full resolution in Canva. Export as PNG. Compress via squoosh.app before every FrameVR upload. Never upload raw Canva exports directly.* # 6. Access & Permissions Access to Canva projects should follow the principle of minimum necessary permissions. The table below reflects current working assignments.
**Role** **Canva Access Level** **Notes**
Charlene (Coordinator) Editor — all projects Primary builder and quality control
Canva Champion (per asset type) Editor — assigned project only One champion per project recommended
Jonathon (CEO) Admin — workspace Brand Kit population pending
General volunteers Viewer or no access Receive exported files, do not edit source
*⚠ Canva Champion assignments are not yet confirmed. Coordinate with Charlene before granting editor access to any project.* # 7. Open Items
**Item** **Owner** **Status**
Confirm in-world dimensions via testing Charlene / Team A ☐ Pending
Populate Brand Kit in Canva 2026 Greece workspace Jonathon ☐ Pending
Assign Canva Champions per project Charlene ☐ Pending
Confirm poster dimensions for poster hall Frames (Aliane) Jonathon / Aliane ☐ Pending
Create iLRN2026\_WayfindingBanners project Charlene ☐ Pending
Create iLRN2026\_LargeBoards project Charlene ☐ Pending
Create iLRN2026\_SquarePosters project Charlene ☐ Pending
Create iLRN2026\_ButtonsIcons project Charlene ☐ Pending
volunteers@immersivelrn.org • https://codex.immersivelrn.org/books/volunteer-workbook # iLRN2026 Virtual Campus design guidelines / template **iLRN 2026 Virtual Campus** **\[Frame ID + #\] — \[Frame Name\]** ##### *(HUB = Hub/High Traffic Frame, CS = Community Space, SP = Special Project, BH = Branch House)* Development & Accessibility Checklist Template \[Campus Location Image or Map\] \[Caption or additional information about space\] **example: BH-05 Science, Technology, Engineering & Mathematics (STEM)**
**Frame Type** (ex. Branch House, BH) **Status** **OPEN**
**Track / Branch** (ex. STEM Education) **Capacity** (ex. 50 users)
**FrameVR URL** [\[https://framevr.io/your-frame-url\]](https://framevr.io/house5-stem) *\*\*see Executive Workbench main spreadsheet*
**Frame Purpose**
\[Describe the purpose of this Frame in 2–3 sentences. What is it for? Who is it for? What does it contribute to the campus?\]
Frame type context: \[Frame type\] — \[brief description of frame type role and any curatorial notes specific to this track or space.\]
**1 Ownership & Governance**
**Frame Lead / Owner**
**Content Contributors**
**Technical Steward**
**Accessibility Reviewer**
**Last Updated**
**2 Learning Design Requirements*** — + UDL 3.0*
\[Frame-specific learning design note: Describe any particular learner diversity considerations, engagement challenges, or pedagogical requirements relevant to this track or frame type.\]
UDL: \[Frame-specific UDL note — describe which UDL principles are most relevant to this track and how the Frame design should respond to them.\]
**Universal Requirements (all frames)** **Criterion / Pass Threshold**
☐ Purpose statement posted in Frame at entry zone *Visible within 10 sec of entering*
☐ Orientation cues for newcomers (what this space is, what to do) *Confirmed by blind test with volunteer*
☐ Asynchronous contribution pathway available (forum, Codex, Discord link) *At least 1 async pathway; URL live*
☐ Content accessible in text form via Codex (Representation — UDL) *Codex page live and linked in Frame*
☐ No color-only navigation cues — all zones/portals have text labels *Confirmed by reviewer*
☐ Emotional tone is welcoming; language is jargon-free at entry *Confirmed by a reviewer external to Frame team*
**Frame-Specific Requirements** **Criterion / Pass Threshold**
☐ \[Frame-specific requirement 1 — describe a design or content requirement unique to this frame or track\] *\[Pass threshold\]*
☐ \[Frame-specific requirement 2 — describe a second design or content requirement unique to this frame or track\] *\[Pass threshold\]*
**3 Design & Build Checklist**
**Layout & Purpose** **Criterion / Pass Threshold**
☐ Frame purpose defined in one sentence, posted at entry *Written purpose statement is visible*
☐ Environment size matches use case *Appropriate environment selected; not over/undersized*
☐ Central meeting / focal area identifiable within 10–15 sec *Walk-through test by the reviewer*
**Navigation** **Criterion / Pass Threshold**
☐ Minimum 2 outgoing portal links to other Frames *≥ 2 portals; 0 dead ends*
☐ Consistent portal visual language (campus-wide asset style) *Matches campus portal standard*
☐ Navigation path from entry to any key area ≤ 15 seconds *Timed walk-through by reviewer*
☐ All portal destinations confirmed live *Click-tested by reviewer*
**Signage** **Criterion / Pass Threshold**
☐ All text is legible on mobile screen at default eye level without zooming *Phone screen test*
☐ No signage relies on color alone *Label or icon accompanies all color-coded elements*
**Zone Setup (if zones are used)** **Criterion / Pass Threshold**
☐ 'Restrict all assets to zones' enabled if zones are in use *Frame settings → restrict assets = ON*
☐ Each zone has a named purpose *Zone names visible in Frame settings*
**4 Performance & Asset Budget*** — check via Frame Settings → Performance Rating or ?debug=true*
FrameVR targets: ≤ 200 draw calls · ≤ 130,000 active faces · ≤ 20 materials. FPS target: 60 desktop, ≥ 40 minimum desktop, ≥ 30 iOS Safari.
**Performance Monitor Readings** **Criterion / Pass Threshold**
☐ FPS ≥ 40 on desktop (Chrome/Edge) *Target 60; below 40 = must fix*
☐ FPS ≥ 30 on iOS Safari mobile *Must pass before launch*
☐ Draw call count ≤ 200 *Babylon Inspector → Stats*
☐ Active face/poly count ≤ 130,000 *Babylon Inspector → Stats*
☐ Material count ≤ 20 *Babylon Inspector → Stats*
☐ Performance Rating not flagged RED in Frame Settings *Yellow = caution; Red = block launch*
**Asset Hygiene** **Criterion / Pass Threshold**
☐ All images compressed before import (squoosh.app) *No raw camera/screen captures*
☐ No Sketchfab model imported without poly-count review *Flagged models resolved or documented*
☐ Unused assets deleted (not just hidden) *Assets list contains only active assets *![](https://codex.immersivelrn.org/uploads/images/gallery/2026-04/gszwA9EgYR6RzwQn-embedded-image-t13oeyir.png) ***Check with the owner of the asset before deletion!!***
**Media Settings** **Criterion / Pass Threshold**
☐ All videos set to NOT autoplay *Each video asset → autoplay = OFF*
☐ Webcam/streaming screens disabled unless live event. *Default OFF; enable only during live sessions*
☐ No Smoke particle effects in use *High GPU cost; zero tolerance*
☐ Animated objects minimized *Each loop adds ongoing GPU cost*
**FPS Desktop**
**FPS iOS Safari**
**Draw Calls**
**Poly Count**
**Materials**
**Perf. Rating**
**5 Content & Boards Checklist**
**Codex & Community Links** **Criterion / Pass Threshold**
☐ Codex page URL embedded as board or link in Frame *BookStack page URL live and linked*
☐ Forum / InVision Community thread linked *Thread URL confirmed live*
**Content Boards** **Criterion / Pass Threshold**
☐ Image board(s) populated with track-relevant content *At least 1 board with real content, not placeholder*
☐ Upcoming events board posted and dated *Event title + date visible; past events removed*
☐ Showcase zone set up for presenter / author work *Distinct area labelled Showcase or equivalent*
☐ Presenter / author content loaded or linked *Confirmed with content owner*
**Conference-Specific Elements** **Criterion / Pass Threshold**
☐ Greek cultural / scavenger hunt artifact placed (if assigned) *Confirm with George / Greek team*
☐ Quest clue placed correctly (if this Frame is a quest stop) *Cross-check against quest master list*
☐ Tally.so submission form linked (if track accepts submissions) *Tally form URL confirmed and tested*
**6 Planned Activities & Events**
**Activity / Event** **Date** **Owner** **Status**
**7 Connected Frames & Portals**
**Destination Frame** **Portal Type** **Notes**
**8 Asset Inventory**
**Asset Name / Description** **Poly Count** **File Size** **Owner**
**9 Accessibility Sign-Off*** — reviewer must complete this, not the Frame owner*
**Wayfinding & Legibility** **Criterion / Pass Threshold**
☐ New user orients within 10 seconds without prior knowledge *Blind test with volunteer*
☐ All text boards legible on mobile at default eye level *Phone screen test*
☐ No element identified by colour or spatial position alone *Confirmed with audio OFF*
**Inclusivity** **Criterion / Pass Threshold**
☐ No flashing or strobing effects *Zero tolerance — photosensitivity risk*
☐ Critical content accessible from a stationary avatar position *No movement required to read key boards*
☐ Language on all boards is plain and welcoming to newcomers *Reviewed by someone outside Frame team*
**Device & Bandwidth** **Criterion / Pass Threshold**
☐ Fully usable on Chrome / Edge desktop *Full navigation completed without crash*
☐ Usable on iOS Safari mobile *Full navigation completed without crash or major lag*
☐ Loads within 30 sec on Slow 3G (Chrome DevTools → Network → Slow 3G) *Slow 3G test completed and passed*
**Sign-Off** **Criterion / Pass Threshold**
☐ Reviewer name and date recorded below *Required before Frame status = Ready*
**Reviewed By**
**Review Date**
**Outcome**
**Follow-Up Items**
**10 Codex Integration (BookStack)**
**Codex Book / Chapter**
**Codex Page URL**
**Last Synced**
**Outstanding Codex Tasks**
**11 Additional Notes & Open Questions**