# Diagram Type Presets

When the user requests a specific diagram type, apply the matching preset below for shapes, styles, and layout conventions. These presets focus on **structural** style keywords, such as ERD's `shape=table;childLayout=tableLayout`; adapt colors and typography to the user's requested visual style.

Each preset ends with a **Review:** line — the type-specific defects to hunt during the visual review's holistic pass, on top of the generic fit, placement, connection, and typography checks.

Read this file when:
- The user names one of these diagram types (ERD, UML class, sequence, C4, architecture, ML/DL model, flowchart, SysML, BPMN, network topology, cross-functional/swimlane)
- You're choosing shape vocabulary or layout direction for a new diagram

## ERD (Entity-Relationship Diagram)

For SQL DDL, derive tables, primary keys, foreign keys, and crow's-foot relations from the schema before authoring. Mermaid ER conversion is suitable for a standard ERD on draw.io 30+; use XML with the styles below when exact table styling or placement is required.

| Element | Style | Notes |
|---------|-------|-------|
| Table | `shape=table;startSize=30;container=1;collapsible=1;childLayout=tableLayout;fixedRows=1;rowLines=0;fontStyle=1;strokeColor=#6c8ebf;fillColor=#dae8fc;` | Each table is a container |
| Row (column) | `shape=tableRow;horizontal=0;startSize=0;swimlaneHead=0;swimlaneBody=0;fillColor=none;collapsible=0;dropTarget=0;points=[[0,0.5],[1,0.5]];portConstraint=eastwest;fontSize=12;` | Child of table, `parent=tableId` |
| PK column | Bold text: `fontStyle=1` on the row | Mark with `PK` prefix or key icon |
| FK relationship | Dashed edge: `dashed=1;endArrow=ERmandOne;startArrow=ERmandOne;` | Use ER notation arrows |
| Layout | TB, tables spaced 300px apart | Group related tables vertically |

**Review:** every column row fully readable inside its table; relationship lines meet tables at row level on the sides, never through the title band; ER end markers visible at both ends and clear of the table border; PK/FK markers present; relationship lines don't cross tables they don't join.

## UML Class Diagram

| Element | Style | Notes |
|---------|-------|-------|
| Class box | `swimlane;fontStyle=1;align=center;startSize=26;html=1;` | 3-section: title / attributes / methods |
| Separator | `line;strokeWidth=1;fillColor=none;align=left;verticalAlign=middle;spacingTop=-1;spacingLeft=3;spacingRight=10;rotatable=0;labelPosition=left;points=[];portConstraint=eastwest;` | Between sections |
| Inheritance | `endArrow=block;endFill=0;` | Hollow triangle arrow |
| Implementation | `endArrow=block;endFill=0;dashed=1;` | Dashed + hollow triangle |
| Composition | `endArrow=diamondThin;endFill=1;` | Filled diamond |
| Aggregation | `endArrow=diamondThin;endFill=0;` | Hollow diamond |
| Layout | TB, classes 250px apart | Interfaces above implementations |

**Review:** all three compartments visible with separators intact; attribute/method text left-aligned and unclipped; hollow inheritance triangles point at the parent; diamonds sit at the owning end; multiplicity labels clear of their lines and of each other.

## Sequence Diagram

Prefer Mermaid conversion for a standard sequence diagram on draw.io 30+. Use the styles below for custom XML diagrams that require exact lifelines, activation bars, message placement, or interaction frames.

| Element | Style | Notes |
|---------|-------|-------|
| Actor/Object | `shape=umlLifeline;perimeter=lifelinePerimeter;whiteSpace=wrap;html=1;container=1;collapsible=0;recursiveResize=0;outlineConnect=0;portConstraint=eastwest;` | Lifeline with dashed vertical line |
| Sync message | `html=1;verticalAlign=bottom;endArrow=block;` | Solid line, filled arrowhead |
| Async message | `html=1;verticalAlign=bottom;endArrow=open;dashed=1;` | Dashed line, open arrowhead |
| Return message | `html=1;verticalAlign=bottom;endArrow=open;dashed=1;strokeColor=#999999;` | Grey dashed |
| Activation box | `shape=umlFrame;whiteSpace=wrap;` on the lifeline | Narrow rectangle on lifeline |
| Layout | LR, lifelines spaced 200px apart | Time flows top to bottom |

**Review:** lifelines parallel, evenly spaced, and long enough for every message; messages horizontal with each label just above its own arrow, touching nothing; message order reads top→bottom as the described flow; activation boxes span exactly the messages they cover; returns dashed and grey.

## C4 Model (System Context / Container / Component)

Use the styles below for C4 diagrams. A Mermaid C4 sketch works for a standard single view on draw.io 30+; use XML when exact C4 styling, multiple pages, or drill-down links are required:

| Element | Style | Notes |
|---------|-------|-------|
| Person | `shape=mxgraph.c4.person2;html=1;whiteSpace=wrap;fontColor=#ffffff;fillColor=#083F75;strokeColor=#06315C;` | Dark-blue person shape, 200×180 |
| Software System | `rounded=1;arcSize=10;html=1;whiteSpace=wrap;fontColor=#ffffff;fillColor=#1061B0;strokeColor=#0D5091;` | 240×120 |
| External System | same, `fillColor=#8C8496;strokeColor=#736782;` | Grey = outside your control |
| Container | same, `fillColor=#23A2D9;strokeColor=#0E7DAD;` | Mid-blue |
| Component | same, `fillColor=#63BEF2;strokeColor=#2086C9;` | Light-blue |
| Database | `shape=cylinder3;size=15;boundedLbl=1;` + Container colors | Cylinder |
| Relationship | `endArrow=blockThin;endFill=1;html=1;fontSize=11;fontColor=#404040;strokeColor=#828282;labelBackgroundColor=#ffffff;` | Grey thin arrow, label = protocol/action |
| Label format | `Name` ⏎ `[Type: Tech]` ⏎ `description` | The standard three-line C4 label |
| Drill-down | wrap the element in `<UserObject link="data:page/id,<pageId>">` | Click jumps to the child page in draw.io / viewer |
| Layout | TB, one `<diagram>` page per level | Export a single page with `--page-index <n>` (1-based) |

**Review:** every element shows its full three-line label inside the shape; relationship labels readable on their white background and clear of other lines; person shapes unclipped; one consistent color per C4 level; external systems visibly grey.

## Architecture Diagram

| Element | Style | Notes |
|---------|-------|-------|
| Layer/tier | `swimlane;startSize=30;` | Containers for grouping: Client / API / Service / Data |
| Service | `rounded=1;whiteSpace=wrap;html=1;` + tier color | Use color palette by tier |
| Database | `shape=cylinder3;whiteSpace=wrap;html=1;` | Green palette |
| Queue/Bus | `rounded=1;whiteSpace=wrap;html=1;fillColor=#fff2cc;strokeColor=#d6b656;` | Yellow — place centrally for hub pattern |
| Gateway/LB | `shape=mxgraph.aws4.resourceIcon;` or `rounded=1;` with orange | Orange palette |
| External | `rounded=1;dashed=1;fillColor=#f5f5f5;strokeColor=#666666;` | Dashed border for external systems |
| Layout | TB or LR by tier count; ≥4 tiers → TB | Hub nodes centered |

**Review:** every child fully inside its tier container with padding on all sides; tier titles not overlapped by children or edges; hub/bus nodes reachable with short direct edges; no edge passes through an unrelated service; colors match the legend.

## ML / Deep Learning Model Diagram

For neural network architecture diagrams — ideal for papers targeting NeurIPS, ICML, ICLR.

| Element | Style | Notes |
|---------|-------|-------|
| Layer block | `rounded=1;whiteSpace=wrap;html=1;` + type color | Main building block |
| Input/Output | `fillColor=#d5e8d4;strokeColor=#82b366;` | Green |
| Conv / Pooling | `fillColor=#dae8fc;strokeColor=#6c8ebf;` | Blue |
| Attention / Transformer | `fillColor=#e1d5e7;strokeColor=#9673a6;` | Purple |
| RNN / LSTM / GRU | `fillColor=#fff2cc;strokeColor=#d6b656;` | Yellow |
| FC / Linear | `fillColor=#ffe6cc;strokeColor=#d79b00;` | Orange |
| Loss / Activation | `fillColor=#f8cecc;strokeColor=#b85450;` | Red/Pink |
| Skip connection | `dashed=1;endArrow=block;curved=1;` | Dashed curved arrow |
| Tensor shape label | Add shape annotation as secondary label: `value="Conv2D&#xa;(B, 64, 32, 32)"` | Use `&#xa;` for multi-line |
| Layout | TB (data flows top→bottom), layers 150px apart | Group encoder/decoder as swimlanes |

**Tensor shape convention:** annotate each layer with input/output tensor dimensions in `(B, C, H, W)` or `(B, T, D)` format. Place dimensions as the second line of the label using `&#xa;`.

**Review:** layer blocks aligned on the flow axis; both label lines (name + tensor shape) readable in every block; skip connections curve clear of blocks and labels; encoder/decoder swimlanes don't clip their children; colors follow the layer-type mapping.

## SysML (Block Definition / Internal Block / Requirement / Parametric)

draw.io ships a native SysML 1.x shape library (`mxgraph.sysml.*`, ~60 shapes). Call `drawio_shapesearch` with `sysml <keyword>` for any element not listed below. Stereotype labels use guillemets as the first label line: `&#171;block&#187;` (HTML entities for « »). SysML behavioral diagrams (activity, state machine, use case, sequence) reuse the UML presets above; search for `sysml activity` or `sysml state` for notation-specific variants.

### Block Definition Diagram (bdd)

| Element | Style | Notes |
|---------|-------|-------|
| Block | `swimlane;fontStyle=1;align=center;startSize=40;html=1;` | Label `&#171;block&#187;&#xa;Name`; compartments (values / parts / operations) like UML class |
| Compartment separator | same `line;...` style as UML Class | Between compartments |
| Composite association | `html=1;endArrow=none;startArrow=diamondThin;startFill=1;` | Filled diamond at the whole (owner) end |
| Reference association | `html=1;endArrow=none;startArrow=diamondThin;startFill=0;` | Hollow diamond |
| Generalization | `edgeStyle=none;html=1;endArrow=block;endFill=0;endSize=12;` | Hollow triangle pointing at the parent block |
| Multiplicity | edge labels `1`, `0..1`, `1..*` near the ends | Offset with edge label geometry |
| Layout | TB, whole block on top, part blocks below, 250px apart | Same convention as UML class |

### Internal Block Diagram (ibd)

| Element | Style | Notes |
|---------|-------|-------|
| Frame | `rounded=0;html=1;verticalAlign=top;align=left;spacingLeft=10;fontStyle=1;container=1;` | Label `ibd [block] Name`; parts are children |
| Part | `rounded=0;whiteSpace=wrap;html=1;` | Label `partName : BlockType` |
| Port | `html=1;shape=mxgraph.sysml.port;sysMLPortType=flowN;` 20×20 | Child of the part, relative geometry pinned to its border |
| Connector | `html=1;endArrow=none;` | Solid line port-to-port |
| Item flow direction | `shape=triangle;fillColor=strokeColor;` 10×10 on the connector + item label | Triangle points along the flow |

### Requirement Diagram (req)

| Element | Style | Notes |
|---------|-------|-------|
| Requirement | `swimlane;fontStyle=1;align=center;startSize=26;html=1;` | Title `&#171;requirement&#187;&#xa;Name`; body compartment `id="R1.1"&#xa;text="..."` |
| Containment | `edgeStyle=none;html=1;startArrow=sysMLPackCont;startSize=12;endArrow=none;` | Crosshair-circle at the parent end |
| deriveReqt / satisfy / verify / refine | `html=1;endArrow=open;endSize=12;dashed=1;` + edge label `&#171;satisfy&#187;` | Dashed open arrow pointing at the requirement |
| Trace | same dashed style, label `&#171;trace&#187;` | |
| Layout | TB, parent requirements above children, 200px apart | Satisfy/verify sources (blocks, test cases) at the bottom |

### Parametric Diagram (par)

| Element | Style | Notes |
|---------|-------|-------|
| Constraint block | `rounded=1;whiteSpace=wrap;html=1;` | Label `&#171;constraint&#187;&#xa;{F = m · a}` |
| Parameter port | `rounded=0;html=1;fontSize=10;` 20×20 on the border | Label = parameter name (`m`, `a`, `F`) |
| Binding connector | `html=1;endArrow=none;` | Solid, no arrows |
| Value property | `rounded=0;whiteSpace=wrap;html=1;` | Label `name : Type` |
| Layout | LR, value properties on the outside, constraints centered | |

**Review (all SysML views):** guillemets render as « » (not raw `&#171;`); stereotype line visible on every element; compartment text unclipped; connector end symbols (diamonds, hollow triangles, crosshair circle) fully visible at the correct end; ports pinned on borders without overlapping labels; dashed dependency labels (`«satisfy»`, `«verify»`, …) clear of their lines.

## BPMN (Business Process)

draw.io ships ~200 native BPMN 2.0 shapes (`mxgraph.bpmn.*`). The official styles carry a long `points=[...]` connection-point list — call `drawio_shapesearch` with `bpmn <element>` for the full string; the styles below omit it for brevity and still render correctly.

| Element | Style | Notes |
|---------|-------|-------|
| Pool | `swimlane;html=1;childLayout=stackLayout;horizontal=1;startSize=30;horizontalStack=0;resizeParent=1;resizeParentMax=0;collapsible=0;` | Container; label rotated in the left header band |
| Lane | `swimlane;html=1;startSize=30;horizontal=0;collapsible=0;fillColor=none;` | Child of the pool, `parent=poolId`, one per role |
| Task | `shape=mxgraph.bpmn.task2;whiteSpace=wrap;rectStyle=rounded;size=10;html=1;container=1;expand=0;collapsible=0;taskMarker=abstract;` | `taskMarker=user\|service\|script\|manual\|send\|receive\|businessRule` for typed tasks |
| Start event | `shape=mxgraph.bpmn.event;html=1;perimeter=ellipsePerimeter;aspect=fixed;outline=standard;symbol=general;verticalLabelPosition=bottom;verticalAlign=top;align=center;labelBackgroundColor=#ffffff;` 50×50 | `symbol=message\|timer` for message/timer start |
| Intermediate event | same, `outline=throwing` (send) or `outline=catching` (receive) | Double circle |
| End event | same, `outline=end;symbol=general` | Thick circle; `symbol=terminate` for terminate end |
| Gateway | `shape=mxgraph.bpmn.gateway2;html=1;perimeter=rhombusPerimeter;outline=none;symbol=none;gwType=exclusive;verticalLabelPosition=bottom;verticalAlign=top;align=center;labelBackgroundColor=#ffffff;` 50×50 | `gwType=exclusive\|parallel\|inclusive\|complex` |
| Sequence flow | `edgeStyle=elbowEdgeStyle;html=1;endArrow=blockThin;endFill=1;` | Solid, filled thin arrow |
| Conditional flow | same + `startArrow=diamondThin;startFill=0;startSize=10;endSize=6;` | Hollow diamond at source |
| Default flow | same + `startArrow=dash;startFill=0;startSize=6;endSize=6;` | Tick at source |
| Message flow | `dashed=1;dashPattern=8 4;endArrow=blockThin;endFill=1;startArrow=oval;startFill=0;startSize=4;endSize=6;html=1;` | Dashed, only **between** pools |
| Data object | `shape=mxgraph.bpmn.data2;size=15;html=1;verticalLabelPosition=bottom;verticalAlign=top;align=center;` 40×60 | Dashed dotted-arrow association |
| Annotation | `html=1;shape=mxgraph.flowchart.annotation_2;align=left;labelPosition=right;` | Open bracket + dashed line |
| Layout | LR inside lanes, events/gateways vertically centered on the flow line | Sequence flows never cross pool borders; message flows never stay inside one |

**Review:** event and gateway labels sit below their symbols without touching lanes or flows; every gateway branch labeled; sequence flows stay inside their pool and message flows only run between pools; lane titles readable; the flow line runs through the vertical center of events and gateways.

## Network Topology

Generic vocabulary is the `mxgraph.networks` library — one shared style prefix, per-element `shape=`. For **vendor-specific** icons (Cisco `mxgraph.cisco19`/`cisco_safe`, rack `mxgraph.rack`, cloud vendors), call `drawio_shapesearch` with specific vendor and device keywords.

Shared prefix (every node below): `fontColor=#0066CC;verticalAlign=top;verticalLabelPosition=bottom;labelPosition=center;align=center;html=1;outlineConnect=0;fillColor=#CCCCCC;strokeColor=#6881B3;gradientColor=none;gradientDirection=north;strokeWidth=2;`

| Element | Append to prefix | Size |
|---------|------------------|------|
| Router | `shape=mxgraph.networks.router;` | 100×30 |
| Switch | `shape=mxgraph.networks.switch;` | 100×30 |
| Firewall | `shape=mxgraph.networks.firewall;` | 100×100 |
| Load balancer | `shape=mxgraph.networks.load_balancer;` | 100×30 |
| Server | `shape=mxgraph.networks.server;` | 90×100 |
| Storage / NAS | `shape=mxgraph.networks.storage;` / `...nas_filer;` | 100×100 / 100×35 |
| PC / Laptop | `shape=mxgraph.networks.pc;` / `...laptop;` | 100×70 / 100×55 |
| Wireless AP | `shape=mxgraph.networks.wireless_hub;` | 100×100 |
| Internet / WAN | `shape=mxgraph.networks.cloud;fontColor=#ffffff;` | 90×50 |
| Zone (subnet/VLAN/DMZ) | `rounded=1;dashed=1;fillColor=#f5f5f5;strokeColor=#666666;verticalAlign=top;fontStyle=1;container=1;` | Container; label = CIDR / zone name |
| Physical link | `html=1;endArrow=none;strokeWidth=2;` | Plain line; label = interface/VLAN |
| Logical/VPN link | `html=1;endArrow=none;dashed=1;` | Dashed |
| Layout | TB by tier: Internet → edge (router/firewall) → distribution (switch/LB) → servers/clients | Group each subnet in a zone container; label links with CIDR/port |

**Review:** device labels below their icons, fully readable, and clear of links; every zone container fully encloses its devices with padding; link labels (interface/VLAN/CIDR) beside the line, never on it; tiers read top→bottom; no link passes through a device it doesn't terminate at.

## Cross-Functional Flowchart (Swimlane)

A flowchart split by **who does what** — one lane per role/department. Node vocabulary reuses the Flowchart preset below; only the container skeleton differs.

| Element | Style | Notes |
|---------|-------|-------|
| Pool (process) | `swimlane;html=1;childLayout=stackLayout;horizontal=1;startSize=30;horizontalStack=0;resizeParent=1;resizeParentMax=0;collapsible=0;` | Outer container, label = process name |
| Lane (role) | `swimlane;html=1;startSize=30;horizontal=0;collapsible=0;fillColor=none;` | Child of pool, one per role/team/system |
| Steps | Flowchart preset styles (Start/End, Process, Decision, I/O) | Each step's `parent` = its lane id; coordinates relative to the lane |
| Handoff edge | `edgeStyle=orthogonalEdgeStyle;html=1;rounded=1;` | Edges crossing lanes are the handoffs — the diagram's point |
| Layout | LR flow inside horizontal lanes; time flows left → right | Keep each step inside its actor's lane; ≥160px horizontal spacing |

**Review:** every step fully inside its own lane; lane titles readable and unobstructed; handoff edges cross lane borders cleanly instead of running along them; the flow reads left→right without backtracking; decision branches labeled.

## Flowchart (enhanced)

| Element | Style | Notes |
|---------|-------|-------|
| Start/End | `ellipse;whiteSpace=wrap;html=1;fillColor=#d5e8d4;strokeColor=#82b366;` | Green oval |
| Process | `rounded=0;whiteSpace=wrap;html=1;fillColor=#dae8fc;strokeColor=#6c8ebf;` | Blue rectangle |
| Decision | `rhombus;whiteSpace=wrap;html=1;fillColor=#fff2cc;strokeColor=#d6b656;` | Yellow diamond |
| I/O | `shape=parallelogram;perimeter=parallelogramPerimeter;whiteSpace=wrap;html=1;fillColor=#ffe6cc;strokeColor=#d79b00;` | Orange parallelogram |
| Subprocess | `rounded=0;whiteSpace=wrap;html=1;fillColor=#e1d5e7;strokeColor=#9673a6;` + double border | Purple |
| Yes/No labels | `value="Yes"` / `value="No"` on decision edges | Always label decision branches |
| Layout | TB, 200px vertical gap | Decisions branch LR, merge back to center |

**Review:** flow reads top→bottom without backtracking; every decision has labeled Yes/No branches leaving different sides, with each label beside its own line; merge-back edges route around nodes through free corridors; start and end shapes visually distinct from process steps.