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2 Refer to Fig. 22.3 which again only displays the 3D viewport 3 Menu bar with Modify-3D Operation-Mirror 3D and: prompt Select objects respond window the model then right-click prompt Specify first point on mirror plane (3 points) or [Object/ Last/ enter XY <R> – the XY plane option prompt Specify point on XY plane<0,0,0> and: right click prompt Delete source objects<Yes/No> and enter: Y <R> then PAN to suit – fig(b) 4 The model at this stage has the AMBIGUITY effect of all 3D models, i.e. are you looking down or looking up? Hence HIDE! 5 At the command line enter MIRROR3D <R> and: prompt Select objects respond window the model then right-click prompt Specify first point on mirror plane respond Intersection icon and pick pt1 prompt Specify second point on mirror plane respond Intersection icon and pick pt2 prompt Specify third point on mirror plane respond Intersection icon and pick pt3 prompt Delete source object<Yes/No> and enter: Y <R> then PAN to suit, then HIDE – fig(c) 3D geometry commands 143 Figure 22.3 The MIRROR 3D command using 3DGEOM model. modelling with AutoCAD.qxd 17/06/2002 15:39 Page 143 6 Activate the Mirror 3D command and: a) window the model the right-click b) select the YZ plane option c) pick intersection of point A as a point on the plane d) enter Y to delete source objects prompt e) pan and hide – fig(d) 7 Using the Mirror 3D command: a) window the model the right-click b) select the ZX option c) enter –50,–50 as a point on the ZX plane d) accept the N default delete source objects option e) pan and hide – fig(e) 8 Shade and 3D orbit, then investigate the layout tabs 9 Save if required. We will not refer to this drawing again. 3D Array The 3D array command is similar in operation to the 2D array. Both rectangular and polar arrays are possible, the rectangular array having rows and columns as well as levels in the Z direction. The result of a 3D polar array requires some thought! Rectangular 1 Open the 3DGEOM drawing, UCS BASE, Model tab active and refer to Fig. 22.4 which displays the MVLAY1 tab 2 At the command line enter 3DARRAY <R> and: prompt Select objects respond window the model then right-click prompt Enter the type of array [Rectangular/Polar] enter R <R> – rectangular option prompt Enter the number of rows( )<1> and enter: 2 <R> prompt Enter the number of columns(|||)<1> and enter: 3 <R> prompt Enter the number of levels(…)<1> and enter: 4 <R> prompt Specify the distance between rows( ) and enter: 120 <R> prompt Specify the distance between columns(|||) and enter: 120 <R> prompt Specify the distance between levels(…) and enter: 100 <R> 3 The model will be displayed in a 2×3×4 rectangular matrix pattern but will ‘be off the screen’. 4 Zoom-extents then hide to display the complete array 5 With MVLAY1 tab active, zoom centre about the point 170,110,185 (why these coordinates) at 400 magnification (550 in 3D view) 6 Hide the model – Fig. 22.4 then Gouraud shade the 3D viewport. 7 Try the 3D orbit command with the shaded model. 8 This exercise does not need to be saved. 144 Modelling with AutoCAD 2002 modelling with AutoCAD.qxd 17/06/2002 15:39 Page 144 Polar 1 Open 3DGEOM, UCS BASE in Model tab 2 Menu bar with Modify-3D Operation-3D Array and: prompt Select objects respond window the model then right-click prompt Enter the type of array and enter: P <R> prompt Enter the number of items and enter: 5 <R> prompt Specify the angle to fill and enter: 360 <R> prompt Rotate arrayed objects and enter: Y <R> prompt Specify center point of array enter 150,150,0 <R> prompt Specify second point on axis if rotation enter @0,0,100 <R> i.e. a vertical line 3 Zoom-all then investigate the MVLAY1 tab – Fig. 22.5(a) 4 Undo the 3D polar array 5 Activate the 3D array command and: a) window the original model then right-click b) enter a polar array type c) number of items: 5 d) angle to fill: 360 e) rotate as copied: Y f) centre point of array and enter: –50,0,0 <R> g) second point on axis and enter: @0,100,0 <R> 6 Zoom-all then hide and shade 7 Investigate the MVLAY1 tab which will need a zoom-extents and then a zoom scale factor – Fig. 22.5(b) 3D geometry commands 145 Figure 22.4 The 3D ARRAY (rectangular) command using 3DGEOM model. modelling with AutoCAD.qxd 17/06/2002 15:39 Page 145 8 Note: a) The first polar array was about a vertical line, the second about a horizontal line. Think about the entered coordinates b) The ARRAY icon/dialogue box is for 2D arrays only 9 This exercise is complete and need not be saved. Align The align commands can be used in 2D or 3D and allows objects (models) to be aligned with each other. 1 Open your MV3DSTD template file, MVLAY1 tab with UCS BASE and layer MODEL current. Refer to Fig. 22.6 2 Using the Surfaces toolbar create the following objects: Box Wedge corner 0,0,0 160,0,0 length 100 100 wedge 80 80 height 50 50 rotation 0 0 colour red blue 3 Copy the box and wedge: a) base point: 0,0,0 b) second point: @150,150 4 Set the running object snap to Intersection 146 Modelling with AutoCAD 2002 Figure 22.5 The 3D ARRAY (polar) using the 3DGEOM model. modelling with AutoCAD.qxd 17/06/2002 15:40 Page 146 5 Menu bar with Modify-3D Operation-Align and: prompt Select objects respond pick a blue wedge then right-click prompt Specify first source point and pick point 1s prompt Specify first destination point and pick point 1d prompt Specify second source point and pick point 2s prompt Specify second destination point and pick point 2d prompt Specify third source point and pick point 3s prompt Specify third destination point and pick point 3d 6 The blue wedge will be aligned with its sloped surface on the top of the box as (a) 7 At the command line enter ALIGN <R> and: a) pick the copied red box then right-click b) pick first source/destination points: pick a and x c) pick second source/destination points: pick b and y d) pick third source/destination points: pick c and z e) the red box will be aligned onto the sloped surface of the wedge as (b) 8 This completes the align exercise. 3D geometry commands 147 Figure 22.6 The ALIGN command with 3D objects. modelling with AutoCAD.qxd 17/06/2002 15:40 Page 147 3D extend and trim Objects can be trimmed and extended in 3D irrespective of the objects’ alignment. The two commands are very dependent on the UCS position. 1 Open your MV3DSTD template file and refer to Fig. 22.7 2 Using the LINE icon draw a square with: start point: 0,0 next point: @100,0 next point: @0,100 next point: @–100,0 next point: close 3 Multiple copy the square with: a) base point: 0,0 b) second point: @0,0,120 and: @0,0,180 4 Scale the top square about the point 50,50,180 by 0.5 5 Draw in the four vertical lines between the two large squares, then draw the following four lines: line start point next point colour 1 25,25,180 @0,–5,–30 blue 2 75,25,180 @5,0,–30 green 3 75,75,180 @0,5,–30 cyan 4 25,75,180 @0,0,–60 magenta 6 Change the viewpoint in the 3D viewport with VPOINT-ROTATE and angles of 300 and 30. The model will be displayed as fig(a). Figure 22.7 The EXTEND and TRIM commands. 148 Modelling with AutoCAD 2002 modelling with AutoCAD.qxd 17/06/2002 15:40 Page 148 Extend 1 With the 3D viewport active, restore UCS RIGHT and select the EXTEND icon from the Modify toolbar and: prompt Select objects respond pick line ab then right-click prompt Select object to extend or [Project/Edge/Undo] enter E <R> – the edge option prompt Enter an implied edge extension mode [Extend/No extend] enter E <R> – the extend option prompt Select object to extend or [Project/Edge/Undo] enter P <R> – the project option prompt Enter a projection mode [None/Ucs/View] enter U <R> – the current UCS option prompt Select object to extend respond pick blue line 1 then right-click/enter 2 Repeat the EXTEND command using the entries E,E,P,U as step 1 and: a) extend the green line 2 to edge bc with UCS RIGHT b) extend the cyan line 3 to edge cd with UCS FRONT 3 The extended lines are displayed as fig(b) Trim 1 Still with the 3D viewport active, restore UCS BASE and select the TRIM icon from the modify toolbar and: prompt Select objects respond pick line wx then right-click prompt Select object to trim or [Project/Edge/Undo] enter P <R> – the project option prompt Enter a projection option [None/Ucs/View] enter V <R> – the view option prompt Select object to trim respond a) make the top right viewport active b) pick the blue line then right-click/enter 2 Repeat the TRIM command with P and V entries as step 1 and: a) trim the green line to edge xy, picking the green line in the top left viewport at the select object to trim prompt b) trim the cyan line to edge yz, picking the cyan line in the top right viewport at the select object to trim prompt 3 The coloured lines have now been extended and trimmed ‘to the top surface’ of the large red box – fig(c) Task 1 Draw four lines connecting the ‘bottom ends’ of the blue, green, cyan and magenta lines 2 Hatch this area 3 Find the hatched area and perimeter. My values were: Area: 3350 and Perimeter: 232.65 3D geometry commands 149 modelling with AutoCAD.qxd 17/06/2002 15:40 Page 149 Summary 1 The commands Rotate3D, Mirror3D and 3DArray are specific to 3D models. 2 Rotate 3D allows models to be rotated about the X,Y and Z axes as well as two specified points and about objects 3 Mirror 3D allows models to be mirrored about the XY, YZ and ZX axes as well as three specified points and objects 3 A rectangular 3D Array is similar to the 2D command but has ‘levels’ in the Z direction. The result of the polar 3D array can be difficult to ‘visualise’ 4 3D models can be aligned with each other. 5 The trim and extend commands can be used in 3D, the result being dependent on the UCS position. Generally objects are trimmed or extended ‘to a plane’. 150 Modelling with AutoCAD 2002 modelling with AutoCAD.qxd 17/06/2002 15:40 Page 150 Blocks and Wblocks in 3D 3D blocks and wblocks are created and inserted into a drawing in a similar manner as 2D blocks and wblocks. The UCS position and orientation is critical. In this chapter we will: a) create a chess set using blocks b) create a wall-clock as wblocks c) save both the models for rendering exercises Creating the models for the blocks 1 Open your MV3DSTD template file with MVLAY1 tab, layer MODEL and UCS BASE current, and the lower left viewport active. 2 In each viewport, zoom centre about the point 120,90,50 at 275 magnification. Refer to Fig. 23.1 Chapter 23 Figure 23.1 The four 3D block details. modelling with AutoCAD.qxd 17/06/2002 15:40 Page 151 3 With the lower left viewport active, create the following two 3D box objects: box1 box2 corner 0,0,0 0,120,0 length 80 80 width 80 80 height 10 10 rotation 0 0 colour number 126 number 220 4 Restore UCS FRONT and make the upper right viewport active. 5 Draw a line with start point: 150,–10 and next point: @0,80 6 In paper space, zoom-window the top right viewport, then return to model space 7 a) Draw the pawn outline as a polyline from: 150,0 using your own design but with the ‘overall’ sizes given as reference. b) Set SURFTAB1 to 16 c) With the REVOLVED SURFACE icon from the Surfaces toolbar, revolve the pawn outline about the vertical line – full circle d) The pawn colour is to be red 8 Still with UCS FRONT, draw a line with start point: 210,–10,–60 and next point: @0,120 9 a) Draw the rook outline as a polyline from: 210,0,–60 using the reference sizes given or create your own design b) Revolve the rook polyline about the vertical line (360 degs) c) The rook colour is to be red 10 Erase the two vertical lines 11 Restore UCS BASE and models displayed as Fig. 23.1. Making the blocks 1 With the lower left viewport active and UCS BASE, menu bar with Draw-Block-Make and: prompt Block Definition dialogue box respond 1. enter name: SQ1 2. enter base point as X: 0; Y:0; Z: 0 3. pick Select objects and pick the green coloured box then right-click 4. Objects: ensure Delete active 5. Preview: Create icon from block geometry active 6. enter description: FIRST SQUARE 7. ensure insert units: millimeters (dialogue box as Fig. 23.2) 8. pick OK 2 The green coloured square will be ‘made into a block’ and should disappear from the screen due to respond 4 3 Using the Block Definition dialogue box, make the other three blocks using the same method as step 1 with the following information: first second third name SQ2 PAWN ROOK insertion pt 0,120,0 150,0,0 210,60,0 object purple box 3D pawn 3D rook description SECOND SQUARE PAWN PIECE ROOK PIECE 4 Now erase the original polyline outlines which should be displayed 5 Activate the block definition dialogue box and scroll at name and the four created blocks should be listed (PAWN, ROOK, SQ1, SQ2) in alphabetical order. 152 Modelling with AutoCAD 2002 modelling with AutoCAD.qxd 17/06/2002 15:40 Page 152 [...]... be investigated during the next example Figure 24.2 The various DVIEW options with DVIEWBLOCK – AutoCAD s house 163 modelling with AutoCAD. qxd 164 17/ 06/ 2002 15:40 Page 164 Modelling with AutoCAD 2002 The house displayed on the screen has been left with the Camera option with entered angles of 30 and 30 We will continue with the screen display and investigate the other dynamic view options This means... Centre dialogue box with blocks explored for C:\MODR2002\CHESS 159 modelling with AutoCAD. qxd 160 17/ 06/ 2002 15:40 Page 160 Modelling with AutoCAD 2002 5 Right-click the SQ1 icon from the Design Center palette and: prompt Shortcut menu respond pick Insert block prompt Insert dialogue box with SQ1 named and dialogue box as before respond cancel the dialogue box and the Design Center 6 This exercise was... view options and enter: X and Model displayed with new twist as fig(c) Figure 24.3 Dynamic view example 2 using MODR2002\ARCHES 167 modelling with AutoCAD. qxd 168 17/ 06/ 2002 15:40 Page 168 Modelling with AutoCAD 2002 6 Use the dynamic view command in the lower viewports with the following entries: lower left lower right options: TArget options: CAmera angles: 40 and –30 angles: 30 and 30 options: CLip,... Millimeters – Fig 23 .6 4 pick OK Figure 23 .6 3 The Write Block dialogue box for BODY Create another two wblocks using the same procedure as step 2 with the following information: wblock2 wblock3 Insertion base point 90,0,90 90,0,10 Objects blue object green object File name FACE DIAL Location C:\modr2002 C:\modr2002 157 modelling with AutoCAD. qxd 158 17/ 06/ 2002 15:40 Page 158 Modelling with AutoCAD 2002 Inserting... ‘house’ modelling with AutoCAD. qxd 162 17/ 06/ 2002 15:40 Page 162 Modelling with AutoCAD 2002 The dynamic view command has eleven options, these being: CAmera,TArget,Distance,POints,Pan,Zoom,TWist,CLip,Hide,Off,Undo The option required is activated by entering the CAPITAL letters at the command line, e.g CA for the camera option, TW for twist etc We will investigate the dynamic view command with two... between 0 and 360 degs 2 The prompt with this option is: Specify new view twist angle 3 The result of the option is dependent on the CAmera/Target angles modelling with AutoCAD. qxd 17/ 06/ 2002 15:40 Page 165 Dynamic viewing 4 Using the TWist option enter angle values of: a) 35 b) –35 c) 180 d) –90 5 This is one of the few AutoCAD commands which allows models to be ‘flipped’ over by 180degs 6 When the four... displayed in the 3D viewport 7 Now erase the five dimensions and restore UCS BASE modelling with AutoCAD. qxd 170 17/ 06/ 2002 15:40 Page 170 Modelling with AutoCAD 2002 Figure 25.1 Viewport specific layer exercise using MODR2002\CHEESE Viewport specific layers 1 Still with the 3D faced model displayed on screen? 2 Menu bar with Format-Layer and: prompt Layer Properties Manager dialogue box respond 1 pick... line 3, start point: 250,0 next point: @0,0,8 6 The three wall clock components will be created as tabulated surface models, so set SURFTAB1 to 16 155 modelling with AutoCAD. qxd 1 56 17/ 06/ 2002 15:40 Page 1 56 Modelling with AutoCAD 2002 7 With the TABULATED SURFACE icon from the Surfaces toolbar: prompt Select object for path curve respond pick the BODY polyline prompt Select object for direction vector... can only be activated with DVIEW at the command line 4 The command can be used: a) directly on models b) interactively using AutoCAD s house 5 The command is used relative to the WCS – observe the prompt line when the command is activated Assignment No specific activity, but investigate DVIEW with some previously created models modelling with AutoCAD. qxd 17/ 06/ 2002 15:40 Page 169 Chapter 25 Viewport... 6 Use the Point option with the following entries: target point camera point a) 0,0,0 1,0,0 b) 0,0,0 0,1,0 c) 0,0,0 0,0,1 d) 0,0,0 1,1,0 e) 0,0,0 1,0,1 f) 0,0,0 1,1,1 g) 1,2,3 0,0,0 h) 0,0,0 1,2,3 7 The option is similar to the VPOINT-VECTOR command 8 When all the points entries have been entered, restore the camera angles of 30 and 30, but do not exit the command 165 modelling with AutoCAD. qxd 166 . MODR2002HILLPAL 160 Modelling with AutoCAD 2002 modelling with AutoCAD. qxd 17/ 06/ 2002 15:40 Page 160 Dynamic viewing Dynamic viewing is a powerful (yet underused) command which is very useful with 3D modelling. Fig. 23.5 1 56 Modelling with AutoCAD 2002 Figure 23.5 Information for creating the three wblocks. modelling with AutoCAD. qxd 17/ 06/ 2002 15:40 Page 1 56 Making the Wblocks 1 Menu bar with Tools-New. snap to Intersection 1 46 Modelling with AutoCAD 2002 Figure 22.5 The 3D ARRAY (polar) using the 3DGEOM model. modelling with AutoCAD. qxd 17/ 06/ 2002 15:40 Page 1 46 5 Menu bar with Modify-3D Operation-Align