Presentation on theme: "3D to 2D Orthographic Projection Delineation Techniques"— Presentation transcript:
1 3D to 2D Orthographic Projection Delineation Techniques Clipping Plane Methodology
2 Graphical Representation The vast majority is 2D representation of 3D objectsTechnical Documentation – Construction Documents, basic communication with peers3D conception –> 2D representation –> 3D realizationComputer Models can be “photographed” – images and line drawings can be generated much faster than can be drawnExtraction Methodology – design in 3D, extract 2D
3 Orthographic Projection A means of representing a three-dimensional (3D) object in two dimensions (2D)A perspective projection with a hypothetical viewpoint—e.g., one where the camera lies an infinite distance away from the object and has an infinite focal length, or "zoom". (parallel projection)Multi-view Orthographic ProjectionAxonometric Orthographic ProjectionNon-Orthographic (Perspective)Orthographic
4 Multi-View Orthographic Each projection plane is parallel to one of the coordinate axes of the object resulting in visual distortion / abstraction
5 Architectural PlanAlso called plan view. a drawing made to scale to represent the top view or a horizontal section of a structure
6 Architectural Section A representation of an object as it would appear if cut by a plane, showing its internal structure.
7 Architectural Elevation A drawing or design that represents an object or structure as being projected geometrically on a vertical plane parallel to one of its sides.
8 Axonometric Axonometric A skewed Orthographic Projection so that multiple sides are visible at oncea three-dimensional object is represented by a drawing having all axes drawn to exact scale, resulting in the optical distortion of diagonals and curvesTrimetric – arbitrary foreshorteningIsometric
9 Isometrica three-dimensional object is represented by a drawing having the horizontal edges of the object drawn usually at a 30° angle and all verticals projected perpendicularly from a horizontal base, all lines being drawn to scale
10 Clipping Planes Uses Orthographic Cameras – Relatively Universal Extracts from solids or surfaces alikeUses two planes perpendicular to the focal length of the camera – Near Clipping Plane and Far Clipping PlaneOnly displays graphical information between the near clip and the far clipping plane
12 Plotting to File with Clipping Planes The clipping plane method can be used in conjunction with the plot to file method. Plotting to file allows three important options in a single method –Allows rendering – allows the use of hidden line projection to “hide” lines that should be obscured with planes in 3D space.Flattens the drawing – gets rid of the Z dimension and flattens the 3D model to a 2D vector drawingSeparates the line drawings – Drawings can be edited in respect to themselves without adversely altering the model
13 Plotting to File with Clipping Planes – AutoCAD Method Import the 3D modelPage Setup Manager for a real-scale vector fileSet up the layout for the desired viewViewScaleUse clipping planes to “cut”Use hidden line rendering on the viewportPlot to fileImport plotted file into a [new] drawingMake it prettyPocheEntourageLine weight
14 Plotting to File with Clipping Planes 3 datasets to manageOriginal model fileMultiple layouts preferably – one for each “view”Vector files (DXB)Individual plot files with extensions that are not .dwg.These are not opened, but importedThe Presentation fileAll vector files are imported here for cleanup and delineation