AutoLISP DWG Generation Patterns

Essential AutoLISP patterns for generating DWG files via APS Design Automation. Used across three features: Tiles, Playground, and Symbol Generator.

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Features Using AutoLISP

Feature	File Location	Description
Tiles	src/lib/tiles/script-generator.ts	Programmatic tile layout generation
Playground	src/lib/playground/prompts.ts	Natural language to DWG via LLM
Symbol Generator	src/lib/symbol-generator/script-prompts.ts	Luminaire plan-view symbols

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Script Structure Template

All generated scripts must follow this structure:

(setvar "cmdecho" 0)
(setvar "filedia" 0)

; === SET METRIC UNITS (mm) ===
(command "-DWGUNITS" 3 2 2 "Y" "Y" "N")

; === LAYER SETUP ===
(command "-LAYER" "Make" "OUTLINE" "Color" "7" "" "")
(command "-LAYER" "Make" "TEXT" "Color" "1" "" "")

; === GEOMETRY ===
; Draw entities with entmake or command
(entmake '((0 . "LINE") (8 . "OUTLINE") (10 0.0 0.0 0.0) (11 100.0 0.0 0.0)))

; === FINALIZE ===
(command "ZOOM" "E")
(command "SAVEAS" "2018" "result.dwg")

⚠️ Critical Rules

MUST include:

• ✅ (setvar "filedia" 0) - Required for headless operation
• ✅ (command "-DWGUNITS" 3 2 2 "Y" "Y" "N") - Sets metric units
• ✅ (command "SAVEAS" "2018" "filename.dwg") - Saves output

MUST NOT include:

• ❌ (command "QUIT") - APS handles process termination
• ❌ Interactive prompts - No dialogs available in headless mode

---

DWGUNITS Command (REQUIRED)

Sets drawing units to metric/millimeters. Must be included in every script.

(command "-DWGUNITS" 3 2 2 "Y" "Y" "N")

Parameter Breakdown

Position	Value	Meaning
1	3	Linear units = Millimeters
2	2	Linear display format = Decimal
3	2	Linear display precision = 0.00
4	"Y"	Scale objects from other drawings = Yes
5	"Y"	Match INSUNITS to drawing units = Yes
6	"N"	Reset scale list = No

Other Unit Codes (for reference)

Code	Unit
1	Inches
2	Feet
3	Millimeters ← FOSSAPP standard
4	Centimeters
5	Meters

Why millimeters? All product specifications in the database are in mm.

---

Entity Creation with entmake

LINE

(entmake '(
  (0 . "LINE")
  (8 . "LAYER_NAME")
  (10 X1 Y1 0.0)    ; Start point
  (11 X2 Y2 0.0)    ; End point
))

Example:

(entmake '((0 . "LINE") (8 . "OUTLINE") (10 0.0 0.0 0.0) (11 100.0 50.0 0.0)))

CIRCLE

(entmake '(
  (0 . "CIRCLE")
  (8 . "LAYER_NAME")
  (10 CX CY 0.0)    ; Center point
  (40 . RADIUS)     ; Radius (NOT diameter!)
))

⚠️ CRITICAL: Specifications often give DIAMETER - always divide by 2 for radius!

Example:

; Drawing a 67mm diameter circle
(setq diameter 67)
(setq radius (/ diameter 2.0))
(entmake '((0 . "CIRCLE") (8 . "OUTLINE") (10 0.0 0.0 0.0) (40 . 33.5)))

ARC

(entmake '(
  (0 . "ARC")
  (8 . "LAYER_NAME")
  (10 CX CY 0.0)           ; Center point
  (40 . RADIUS)            ; Radius
  (50 . START_ANGLE_RAD)   ; Start angle in RADIANS
  (51 . END_ANGLE_RAD)     ; End angle in RADIANS
))

⚠️ ANGLES ARE RADIANS! Convert degrees to radians:

(setq angle_radians (* angle_degrees (/ pi 180)))

; Example: 90 degree arc from 0 to 90
(setq start_rad 0.0)
(setq end_rad (* 90 (/ pi 180)))  ; = 1.5708
(entmake '((0 . "ARC") (8 . "OUTLINE") (10 0.0 0.0 0.0) (40 . 50.0) (50 . 0.0) (51 . 1.5708)))

LWPOLYLINE (Closed Rectangle)

(entmake '(
  (0 . "LWPOLYLINE")
  (100 . "AcDbEntity")
  (8 . "LAYER_NAME")
  (100 . "AcDbPolyline")
  (90 . 4)              ; Number of vertices
  (70 . 1)              ; 1=closed, 0=open
  (10 X1 Y1)            ; Vertex 1 (2D only)
  (10 X2 Y2)            ; Vertex 2
  (10 X3 Y3)            ; Vertex 3
  (10 X4 Y4)            ; Vertex 4
))

Example - 100mm x 50mm rectangle centered at origin:

(setq half_w (/ 100 2.0))  ; 50mm
(setq half_h (/ 50 2.0))   ; 25mm
(entmake '(
  (0 . "LWPOLYLINE")
  (100 . "AcDbEntity")
  (8 . "OUTLINE")
  (100 . "AcDbPolyline")
  (90 . 4)
  (70 . 1)
  (10 -50.0 -25.0)  ; Bottom-left
  (10 50.0 -25.0)   ; Bottom-right
  (10 50.0 25.0)    ; Top-right
  (10 -50.0 25.0)   ; Top-left
))

MTEXT (Multiline Text)

(entmake (list
  '(0 . "MTEXT")
  '(100 . "AcDbEntity")
  '(8 . "TEXT")
  '(100 . "AcDbMText")
  '(10 X Y 0.0)         ; Insertion point
  '(40 . TEXT_HEIGHT)   ; Text height (mm)
  '(41 . COLUMN_WIDTH)  ; Column width (mm)
  '(71 . ATTACHMENT)    ; Attachment point (see below)
  (cons 1 "Your text here\\PNext line")
))

Attachment point codes (71):

Code	Position
1	Top Left
2	Top Center
3	Top Right
4	Middle Left
5	Middle Center ← Common
6	Middle Right
7	Bottom Left
8	Bottom Center
9	Bottom Right

MTEXT formatting codes:

Code	Effect
\\P	New line
\\L...\\l	Underline
{\\C1;text}	Color (1=red, 3=green, 5=blue)
{\\H1.5x;text}	Height 1.5x

Example:

(entmake (list
  '(0 . "MTEXT")
  '(100 . "AcDbEntity")
  '(8 . "TEXT")
  '(100 . "AcDbMText")
  '(10 0.0 -100.0 0.0)
  '(40 . 3.5)
  '(41 . 200.0)
  '(71 . 5)
  (cons 1 "DELTA-123456\\PDOWNLIGHT 67MM")
))

---

Layer Management

Create Layer with Color

(command "-LAYER" "Make" "LAYER_NAME" "Color" "COLOR_NUM" "" "")

Example:

(command "-LAYER" "Make" "OUTLINE" "Color" "7" "" "")  ; White
(command "-LAYER" "Make" "TEXT" "Color" "1" "" "")     ; Red
(command "-LAYER" "Make" "DIMS" "Color" "3" "" "")     ; Green

DXF Color Codes

Code	Color	Use Case
1	Red	Text, important info
2	Yellow	Warnings
3	Green	Dimensions
4	Cyan	Construction lines
5	Blue	Water/special
6	Magenta	Highlights
7	White	Standard outlines

Add color to entity:

(entmake '((0 . "LINE") (8 . "OUTLINE") (62 . 7) (10 0.0 0.0 0.0) (11 100.0 0.0 0.0)))
;                                        ↑ color code

Set Current Layer

(setvar "CLAYER" "LAYER_NAME")

Load Linetype (e.g., DASHED)

(command "-LINETYPE" "Load" "DASHED" "" "")
(command "-LAYER" "Ltype" "DASHED" "LAYER_NAME" "")

---

Image Insertion (for Tiles feature)

(command "-IMAGE" "Attach" "path/to/image.png" "X,Y" "SCALE" "0")

Example:

(command "-IMAGE" "Attach" "product.png" "0,0" "1.0" "0")

Notes:

• Images must be uploaded to APS bucket before script execution
• Paths are relative to script working directory
• Scale 1.0 = 1 pixel = 1 mm (for 300dpi images at 1500x1500)

---

Block Operations

Create Block with entmake

; 1. Start block definition
(entmake '((0 . "BLOCK") (2 . "BLOCKNAME") (10 0.0 0.0 0.0) (70 . 0)))

; 2. Add entities (layers still needed)
(entmake '((0 . "LINE") (8 . "0") (10 0.0 0.0 0.0) (11 10.0 0.0 0.0)))
(entmake '((0 . "CIRCLE") (8 . "0") (10 5.0 5.0 0.0) (40 . 3.0)))

; 3. End block
(entmake '((0 . "ENDBLK") (8 . "0")))

; 4. Insert block
(entmake '(
  (0 . "INSERT")
  (2 . "BLOCKNAME")
  (8 . "LAYER_NAME")
  (10 X Y 0.0)      ; Insertion point
  (41 . 1.0)        ; X scale
  (42 . 1.0)        ; Y scale
  (50 . 0.0)        ; Rotation (radians)
))

Insert Block with command

(command "-INSERT" "BLOCKNAME" "X,Y" "XSCALE" "YSCALE" "ROTATION_DEGREES")

---

Common Calculations

Center a Rectangle

(setq width 100)
(setq height 50)
(setq half_w (/ width 2.0))
(setq half_h (/ height 2.0))

; Corners:
; (-50, -25), (50, -25), (50, 25), (-50, 25)

Degrees to Radians

(setq angle_rad (* angle_deg (/ pi 180)))

; Common angles:
; 0° = 0.0
; 45° = 0.7854
; 90° = 1.5708
; 180° = 3.1416
; 270° = 4.7124
; 360° = 6.2832

Diameter to Radius

(setq diameter 67)
(setq radius (/ diameter 2.0))  ; 33.5

Distance Between Points

(setq dx (- x2 x1))
(setq dy (- y2 y1))
(setq distance (sqrt (+ (* dx dx) (* dy dy))))

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APS Design Automation Requirements

Environment Constraints

• Headless mode: No interactive dialogs (filedia=0)
• No QUIT command: APS handles process termination
• File paths: Relative to working directory
• Output: Must use SAVEAS with explicit filename

File Upload Workflow

1. Upload images/assets to APS OSS bucket
2. Create script referencing uploaded files
3. Upload script to bucket
4. Submit WorkItem with script + assets
5. Download generated DWG from output

Debugging Failed Scripts

Common errors:

• Missing DWGUNITS → Drawing uses wrong units
• Missing SAVEAS → No DWG output generated
• Using QUIT → Process terminates before completion
• Diameter instead of radius → Circles twice as large
• Degrees instead of radians → Arcs at wrong angles
• Missing filedia=0 → Script waits for dialog input

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Complete Example: Tile Layout

; Headless setup
(setvar "cmdecho" 0)
(setvar "filedia" 0)

; Set metric units (mm)
(command "-DWGUNITS" 3 2 2 "Y" "Y" "N")

; Create layers
(command "-LAYER" "Make" "OUTLINE" "Color" "7" "" "")
(command "-LAYER" "Make" "TEXT" "Color" "1" "" "")
(command "-LAYER" "Make" "IMAGE" "Color" "5" "" "")

; Draw border (200mm x 200mm)
(setq size 200)
(setq half (/ size 2.0))
(entmake '(
  (0 . "LWPOLYLINE")
  (100 . "AcDbEntity")
  (8 . "OUTLINE")
  (100 . "AcDbPolyline")
  (90 . 4)
  (70 . 1)
  (10 -100.0 -100.0)
  (10 100.0 -100.0)
  (10 100.0 100.0)
  (10 -100.0 100.0)
))

; Insert product image
(setvar "CLAYER" "IMAGE")
(command "-IMAGE" "Attach" "product.png" "-75,-75" "1.0" "0")

; Add product text
(entmake (list
  '(0 . "MTEXT")
  '(100 . "AcDbEntity")
  '(8 . "TEXT")
  '(100 . "AcDbMText")
  '(10 0.0 -105.0 0.0)
  '(40 . 3.5)
  '(41 . 180.0)
  '(71 . 5)
  (cons 1 "DELTA-123456\\PDOWNLIGHT 67MM")
))

; Finalize
(command "ZOOM" "E")
(command "SAVEAS" "2018" "tile.dwg")

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Quick Reference

Critical Rules Checklist

• (setvar "filedia" 0) included
• (command "-DWGUNITS" 3 2 2 "Y" "Y" "N") included
• All dimensions in millimeters
• Circles use radius, not diameter
• Arc angles in radians, not degrees
• All points are 3D (include 0.0 for Z)
• (command "SAVEAS" "2018" "filename.dwg") included
• NO (command "QUIT") command

Common Mistakes

❌ Wrong	✅ Correct
(40 . 67) for 67mm diameter	(40 . 33.5) (radius = diameter/2)
(50 . 90) for 90° arc	(50 . 1.5708) (radians = deg × π/180)
(10 100 50)	(10 100.0 50.0 0.0) (include Z coordinate)
Missing DWGUNITS	Always include DWGUNITS command
(command "QUIT")	Never use QUIT (APS handles termination)
No SAVEAS	Always use SAVEAS to create output

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See Also

• Tiles feature: docs/features/tiles.md
• Playground feature: docs/features/playground.md
• Symbol Generator: docs/features/symbol-generator.md
• Full AutoLISP reference: docs/development/autolisp-reference.md