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Converting 2D parts to 3D parts in Photopia

  1. Import the 2D drawing containing the reflector profile by selecting File/Import CAD File from the main menu. The following steps assume that the 2D geometry is constructed in the XY plane and therefore imports into the XY plane of Photopia's World Coordinate System (WCS). Photopia uses local coordinate systems called Construction Planes (CPlanes). The current CPlane is indicated in Photopia's CAD system using a red line for the X-axis and a blue line for the Y-axis. The orientation of the WCS is always shown in the lower left corner of the CAD view with the same color conventions, while adding a green Z-axis. The origin (0,0,0) of the CPlane is indicated with a circle and cross hair. See Chapter 4 of the User's Guide for more information about CPlanes. The image below shows the Photopia CAD screen in the Isometric View and illustrates the WCS icon in the lower left corner and the CPlane axes.

  2. Define new layers in Photopia for 2D profiles and 3D surfaces for the various luminaire components, i.e. Profile-Main, Refl-Main, Profile-Louver, Refl-Louver, Profile-Lens, Tran-Lens, etc.
  3. Delete extraneous geometry so that only the essential geometry remains that is required to make the 3D surfaces of the various luminaire parts, i.e. lines or polylines describing the reflector profile, lens profile and lamp holder locations. To delete entities in Photopia's CAD system, you can select them individually by clicking on them or select by window or crossing by dragging a window from left to right or right to left, respectively. If all items are linked together in a block, then you can use the EXPLODE command to separate them.
  4. Change the properties of the 2D entities so that they reside on the appropriate layers just created i.e. put the main reflector profile on layer Profile-Main. To change an entity's layer, select it in the CAD view and change its layer in the property control on the right side of the screen. To de-select an entity, press the Escape key.
  5. Move the entities (lines, arcs, etc.) that comprise the 2D profiles of the luminaire components so that the center of the luminaire opening is located at (0,0,0) in Photopia's WCS. Type Move or "M" at the command line or choose Modify / Move from the main menu to start the Move command.
  6. Use the ROTATE command to rotate the 2D profiles of the luminaire components so that the reflector opening is oriented toward the +Y axis, assuming the luminaire produces downward directed light. Rotate it toward the +Y axis if the luminaire produces upward directed light.

  7. Change the view to an isometric view that allows the geometry to be seen in 3D. This can be done by right clicking your mouse in the CAD view and choosing Standard Views / Isometric View from the pop-up menu.

  8. The 2D profiles need to be rotated into the Front View (World XZ plane) so that the 3D luminaire is constructed in the right plane. Photopia requires that the beam center for direct luminaires be toward the world -Z axis and the beam center for indirect luminaires be toward the +Z axis. The final step references more information about the required luminaire orientation. Since Photopia does not yet include a 3D rotate command, you will use the standard ROTATE command, which always rotates about the Z-axis of the current CPlane. Therefore, in order to rotate the reflector profile(s) about the world X-axis, the CPlane needs to be set to one of the side views. You will use the Right Side View, which is the world YZ plane. Select Settings / Construction Plane from the main menu, enter "O" for Ortho and "R" for Right. You will see the CPlane axes rotate so that its X-axis aligns with the world Y and its Y-axis aligns with the world Z.

  9. Select all of the reflector profiles and start the ROTATE command. Enter 0,0 for the base point and 90 degrees for the rotation angle. The reflector should now be rotated into the world XZ plane as shown in the following image.

  10. If the reflector is comprised of linear extrusions, then you will use the EXTRUDE command. This command extrudes the reflector along the Z-axis of the current CPlane, centering the extrusion about the location of the profile. If the reflector needs to be revolved, then you will use the REVOLVE command. This command revolves the reflector about either the X or Y axis or an arbitrary axis you select. Whether you are extruding or revolving your reflector, you need to change the CPlane to the Front View. So start the CPLANE command, then entering "O" for Ortho and "F" for Front.

  11. If your reflector profile includes arc entities, then you need to set the resolution of the 3D mesh that will represent the arc. A higher resolution models the shape of the arc more smoothly. For extrusions, enter the SURFTAB1 command and specify the number of segments that will be used to represent it in the mesh. For revolved surfaces, the SURFTAB1 parameter represents the number of segments around the circumference of the mesh, i.e. the smoothness of the circle. The resolution of arc for revolved surfaces is set by the SURFTAB2 parameter.
  12. If the reflector is a linear extrusion, then construct the end plates using either the POLYGON command or by drawing a horizontal line across the end of the reflector and then using the EXTRUDE command to create a flat plane. Note that POLYGONS in Photopia are triangles, so you will need to draw 2 to make a rectangular end plate. You can use the osnap features to help draw these entities.
  13. Once the 3D reflectors have been constructed, then you need to ensure they are properly oriented. You can check a surface's orientation by putting the CAD view in the Show Surface Orientation mode. This is an option under View Style on the pop-up menu you get by right clicking in the CAD view. Photopia renders the "front" side of surfaces in the color of its layer and the back side in the opposite color. The reflector materials are applied to the front side of materials and the back side is generally black, so it is important that they are properly oriented. View your model in this mode and orbit around it to confirm the surface orientations. If any of the meshes are oriented incorrectly, then use the Modify / Orient tool to fix them. Select the mesh, then run this tool and enter "R" for reverse.
  14. Import the appropriate lamp model for the design by selecting File / Import Lamp on the main menu. Enter the location(s) for the lamp. You will be prompted for multiple locations, so just press Enter again at prompt when you are finished entering the locations you require. Use the rotate command in the appropriate CPlane if the lamp needs to be rotated into different orientation than its default.

  15. See the FAQ topic on Photometric Conventions for more information about the proper orientation of the luminaire, which depends on the type of distribution it creates and your region of the world. Different regions use different standard conventions for photometry.

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