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Sub Surface not being drawn because "base surface has less than 3 points".

asked 2025-02-07 16:48:56 -0500

updated 2025-02-11 15:25:47 -0500

Below example text output of Open Studio Sketchup Plug-In File Errors and Warnings. I have multiple of these errors after performing surface matching and intersecting of surfaces. I have visually inspected the base surfaces to be sound. What is happening?

Error: Sub Surface 395 This sub surface's base surface 'Surface 399' has less than 3 points, it cannot be drawn.

Error: Sub Surface 883 This sub surface's base surface 'Surface 2438' has less than 3 points, it cannot be drawn.

Error: Sub Surface 138 This sub surface's base surface 'Surface 1943' has less than 3 points, it cannot be drawn.

Example:

OS:SubSurface,
  {869704f3-8c02-4b9d-a2b2-09b7e587013f}, !- Handle
  Sub Surface 395,                        !- Name
  Door,                                   !- Sub Surface Type
  ,                                       !- Construction Name
  {7b1acc3c-1f95-4a64-a585-e4e649f5458a}, !- Surface Name
  ,                                       !- Outside Boundary Condition Object
  ,                                       !- View Factor to Ground
  ,                                       !- Frame and Divider Name
  ,                                       !- Multiplier
  ,                                       !- Number of Vertices
  17.832832, 0, 2.032,                    !- X,Y,Z Vertex 1 {m}
  17.832832, 0, 0,                        !- X,Y,Z Vertex 2 {m}
  18.848832, 0, 0,                        !- X,Y,Z Vertex 3 {m}
  18.848832, 0, 2.032;                    !- X,Y,Z Vertex 4 {m}

OS:Surface,
  {7b1acc3c-1f95-4a64-a585-e4e649f5458a}, !- Handle
  Surface 399,                            !- Name
  Wall,                                   !- Surface Type
  ,                                       !- Construction Name
  {9ac4f02a-5a8c-414d-9225-10d8e38e29c3}, !- Space Name
  Surface,                                !- Outside Boundary Condition
  {3f3ba925-c317-411c-ab04-62e1acec8ada}, !- Outside Boundary Condition Object
  NoSun,                                  !- Sun Exposure
  NoWind,                                 !- Wind Exposure
  ,                                       !- View Factor to Ground
  ,                                       !- Number of Vertices
  5.77529135625809e-15, -5.77529135625809e-15, 3.048, !- X,Y,Z Vertex 1 {m}
  5.77529135625809e-15, -5.77529135625809e-15, 0, !- X,Y,Z Vertex 2 {m}
  34.292032, -5.77529135625809e-15, 0,    !- X,Y,Z Vertex 3 {m}
  34.292032, -5.77529135625809e-15, 3.048; !- X,Y,Z Vertex 4 {m}

I see that the vertices for the Surface are approaching but not quite 0. I unfortunately do not have a file from before the matching with all of the information.

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Comments

This is caught here (Line 63). Did you keep a copy of the original .osm file (before attempting to match/intersect surfaces)? If so, can you share it (e.g. Google Drive)? Short of sharing the file in its entirety, can you edit your question by posting the .osm file excerpts for Sub Surface 395 and Surface 399? Open the .osm file with a text editor, and copy/paste both excerpts.

Denis Bourgeois's avatar Denis Bourgeois  ( 2025-02-08 13:55:47 -0500 )edit

1 Answer

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answered 2025-02-10 22:57:58 -0500

updated 2025-02-12 13:58:32 -0500

... "vertices for the Surface are approaching but not quite 0". That's OK, IMO. Both set of coordinates seem fine at first glance. A few suggestions:

A) Try raising the door sill by 0.025 (i.e. an inch):

  17.832832, 0, 2.032,                    !- X,Y,Z Vertex 1 {m}
  17.832832, 0, 0.025,                    !- X,Y,Z Vertex 2 {m}
  18.848832, 0, 0.025,                    !- X,Y,Z Vertex 3 {m}
  18.848832, 0, 2.032;                    !- X,Y,Z Vertex 4 {m}

... SketchUp sometimes has a hard time with a subsurface edge aligned with its base surface edge.

B) Surface 399 is an interzone surface. It's facing some other wall, {3f3ba925-c317-411c-ab04-62e1acec8ada} - you may want to validate its coordinates as well.

C) As Surface 399 is an interzone surface, Sub Surface 395 must also reference a matching subsurface ... with the adjacent base surface, {3f3ba925-c317-411c-ab04-62e1acec8ada}, as its parent. Its "Outside Boundary Condition Object" can't be left blank like that. With a text editor, CTRL-F {3f3ba925-c317-411c-ab04-62e1acec8ada} to check if there's a paired subsurface for Sub Surface 395. If not, you can try adding one e.g.:

OS:SubSurface,
  {869704f3-8c02-4b9d-a2b2-09b7e587013x}, !- Handle
  Sub Surface 395x,                       !- Name
  Door,                                   !- Sub Surface Type
  ,                                       !- Construction Name
  {3f3ba925-c317-411c-ab04-62e1acec8ada}, !- Surface Name
  {869704f3-8c02-4b9d-a2b2-09b7e587013f}, !- Outside Boundary Condition Object
  ,                                       !- View Factor to Ground
  ,                                       !- Frame and Divider Name
  ,                                       !- Multiplier
  ,                                       !- Number of Vertices
 18.848832, 0, 2.032;                     !- X,Y,Z Vertex 4 {m}
 18.848832, 0, 0.025,                     !- X,Y,Z Vertex 3 {m}
 17.832832, 0, 0.025,                     !- X,Y,Z Vertex 2 {m}
 17.832832, 0, 2.032,                     !- X,Y,Z Vertex 1 {m}

... a bit tricky doing this by hand. Make sure its handle is unique. If unsuccessful, try deleting Sub Surface 395.

Hope this helps.


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Asked: 2025-02-07 16:48:56 -0500

Seen: 140 times

Last updated: Feb 12