Hey it s Audrey 1 HEY IT S AUDREY

Transcription

1 Hey it s Audrey 1 HEY IT S AUDREY Houdini Training 4.0 Side Effects Software

2 2 BEWARE OF THE PLANT! 2.1 SETTING UP 1. Launch Houdini. 2. From the Desktop selector button, select the Training desktop. 3. Delete the ground object. 4. Rename logo - Pot In its shading folder, change the material assignment from text to none. 5. Rename sky - Stem set its material assignment, in its Shading folder from sky to none open the Misc folder. Change the Object s wireframe color to in RGB mode. Toggle off its Display flag (for now) 6. Reposition light1 to Delete the light2 and light3 objects. 8. Decrease the Global Animation Length to 150 Frames choosing to squash the animation. Click on the parameter button associated with the playback field. In the End field change enter 150. Close the Parameter window when done. 2 Side Effects Software 1999 Houdini Training 4.0

3 2.2 CREATING THE POT 1. Pass the Pot Object node into the SOP Editor Change the main viewing window to view the SOP editor, and that it is viewing the Pot objects SOP editor. Delete the default xform1 SOP. Ensure the viewport display mode is set to Current SOP. Working with the existing File SOP. FILE SOP 1. Load the geo file potprofile.bgeo /?/?/Geo/potprofile.bgeo Home the viewport window If you don t have this file see appendix at the end of this document to construct it. REVOLVE SOP CONVERT SOP 1. Toggle into Shaded view mode. This can be done by putting the mouse pointer over the viewport window and pressing the w key. Toggle on its Display and Render flags Display the SOP info window 70 points 70 vertices 1 mesh FACET SOP 1. Toggle the Unique Points option On Toggle on its Display and Render flags. note the hard shading effect due to the points no longer being shared by adjutant edges as verified by the information window 240 points 60 primitives 240 vertices Houdini Training 4.0 Side Effects Software

4 60 polygons 2. Toggle shaded mode Off once again. 2.3 CREATING THE SPINE 1. Return the Tile Layout window to the Object editor, and toggle on the Display flag of the Stem object. 2. Enter into the Stem objects SOP editor. Ensure that that viewport window is changed to view the Stem objects SOP editor. Delete the default sphere and texture Sops If it is not, change the viewport display mode to Current SOP CIRCLE SOP LSYSTEM SOP Primitive Type NURBS Home the viewport window Radius 0.03 Rules Folder Divisions 6 Premise F Rule1 F=F~(40)J/F Rule2 Values Folder Angle 23 Geometry Folder Generations 5 Random Seed 20 SWEEP SOP Circle SOP is cross sectional input Lsystem is backbone input 4 Side Effects Software 1999 Houdini Training 4.0

5 PRIMITIVE SOP 1. Display primitive numbers Group parameter field (grouping out primitives 12 and 13) Toggle On the Do Transformation option Scale Toggle Primitive numbers Off once again SKIN SOP 3. At the bottom of the viewport window, toggle on the See one/all objects button. This will allow you to view the Pot object as well as the Stem object in world space. If you are not currently viewing the complete pot and the fully Skinned Spine object, then go back into the appropriate SOP networks and ensure that the Display flag is toggled On for the last SOP in the network chain. Problem Pot to large Stem to small 4. Working with the network chain that creates the Pot object, append a Transform SOP to the Facet SOP. Scale Remember to toggle on the Display and Render flag for the Transform SOP in order to see the changes in Object space. Houdini Training 4.0 Side Effects Software

6 5. Working with the network chain that creates the Stem object, append a Transform SOP to the Skin SOP. Scale Once again toggle the Display flag of the Transform SOP on, so that you will see the changes in object space. Toggle off the See one/all objects 2.4 ANIMATING THE SWALLOW 1. Insert a Group SOP between the Sweep SOP and the Primitive SOP. 2. Working with the Group SOP parameters: Toggle on the Number Enable options On Set the Operation option to Group By Range Click on the Start/End button. This will enable you to enter expressions in both fields. Set the Range pattern (start/end) to $F and ($F)+1 respectively Set the Select every_? of? parameter to 1 and 1 respectively 3. Delete the current specification in the Primitive SOPs group field (12 13) and replace it with Group1. 4. Play back the animation and the swallow is taken care of. However, there is a problem. Because $F returns values of 1 through 150 and there are only some 33 primitives, the whole swallow is over in the first 32 frames. Therefore: 6 Side Effects Software 1999 Houdini Training 4.0

7 5. Select the Group SOP to maker it the active SOP. Hold down the C key, and the \. This will bring up an options menu. Select Add Spare Channels. In the channel name field, change it to swallow. Hit the Accept button. At the top of the parameter window, click on the editor menu button, and select the channel editor. In the tile layout window scope the channel for the Group SOP by pressing the v key. 6. Set the swallow channel s values to 0 and 32 respectively with a linear interpolation type. 7. Return the Channel Editor menu to the Parameter Editor Working with the Group SOPs parameters: [ on the Start/End field to modify the existing expressions in each field. Replace $F and ($F)+1 with ch( swallow ) and ch( swallow )+1 respectively. 8. Play back the animation once again. The swallow now addresses the 33 primitives over the entire 150 frame range. However... The Stem is not in the correct position or orientation in relation to the Pot Houdini Training 4.0 Side Effects Software

8 The Stem object needs to be rotated into the correct orientation in relation to the pot and then translated into its final position. 1. Toggle on the See one/all objects. Append a Primitive SOP to the Transform SOP that was used to scale the Stem object. Toggle on the Do Transformation button. interactively rotate the stem primitive about the X axis 230 degrees interactively rotate the stem primitive about the Z axis 310 degrees Generally, if you rotate on only two axis, then the rotations are pretty straight forward as they were here. However, rotating the object on the third axis within the same SOP requires some understanding of how the Rotate Order parameter works. In this example you now want to rotate the Stem about the Y axis so that it oriented to the right hand side of the pot rather than on the left hand side and this is where the problem will become apparent. To illustrate this: try interactively rotating the spine primitive about the Y axis Immediately you will realize that the Y axis is no longer aligned with the Y axis in the world due to the previous rotations. Therefore: 2. Set the rotation on the Y axis back to 0 once again. 3. Change the rotate order to Rx, Rz, Ry. 4. Now interactively rotate the Stem about the Y axis 160 degrees. With the rotate order changed, the Y rotation is now calculated before the Z rotation which throws the Y axis out of alignment with the world and gives you the result you were after. This could also have been accomplished by using two Primitive SOPs. The first SOP could have been used to effect the X and Z rotations and the second SOP used to effect the Y rotation. However, in this way you have alleviated a SOP and your ultimate goal is to create the effect you want with the least number of SOPs and therefore the least amount of compute time on the part of the system s CPU. Now the Stem can be translated into it s final position relative to the Pot. To do this: 1. Ensure you are still viewing all 4 view windows. If you are not, press the 5 key to toggle the four view window display and then home each of the view windows. Continuing with the Primitive SOP. Translate 2.5 units on the Z axis Translate 0.6 units on the X axis Translate 0.5 units on the Y axis 8 Side Effects Software 1999 Houdini Training 4.0

9 2. Toggle off the See One/All button located at the bottom of the viewport window. 3. Press the 2 key to return to the Perspective window. CREATING THE THORNS Starting a new SOP network to the right of the current network: TUBE SOP Primitive Type NURBS Radius Height 0.23 Orientation Z axis Detail columns set to 4 COPY SOP # of copies 14 ALIGN SOP the copy Sop (tube network) is the align source pipe the last Primitive SOP (the stem output) into the right input as the auxiliary source 1. Toggle off the options for Individual Alignment Translate Rotate 2. Toggle the Translate option On and set the Bias parameter to 1 3. Toggle the Individual Alignment option On 4. Set the Right UV parameters to 0 and 0.02 respectively 5. Set the Right UV End parameters to 0 and.93 respectively 6. Set the Right UV End parameters to 0 and.93 respectively 7. Toggle the Rotate option On Open the Transform folder and: interactively rotate the primitive about the X axis to a value of set the translate parameter for the Z axis to a value of Bias 1 Left UV 0 0 Right UV Right UV end Houdini Training 4.0 Side Effects Software

10 8. Ensure that the Align SOP is currently selected and copy it using the Ac keyboard command. 9. Use the Av keyboard command to paste the copy three times in a horizontal row to the right of the original Align SOP. 10. Edit the Align2, Align3 and Align4 SOPs to reflect changing Right U and Right U End values. Bias 1 Left UV 0 0 Right UV Right UV end Bias 1 Left UV 0 0 Right UV Right UV end Bias 1 Left UV 0 0 Right UV Right UV end MERGE SOP To place a SOP without having to click on the output connector of a SOP: While working in the tile layout window. Press the T key to bring up the SOP menu. Select Filters, and then select a Merge SOP. Pipe the Primitive SOP and all 4 Align SOPs into the Merge SOP for final display and ensure the Merge SOPs display flag is toggled On. Now the Stem and the Thorns will be grouped out into two separate groups so that two separate materials can be applied to them. 1. Display primitive numbers GROUP SOP Group Name Stem Number Enable On Pattern 0 Stem is grouped Open Combine Folder, Enter Thorns in the first field. Click on the Compliment button In the second Group field, select Stem from the group lister button. Compliment button What you are doing with the combine folder is to create a second group out of any primitive that does not belong to the first group. In this case, all of the thorns become a group, 10 Side Effects Software 1999 Houdini Training 4.0

11 and the stem is in its own group. Doing this with the Combine folder saves you using another Group SOP. Creating primitive Groups will make it easier to apply textures. MATERIAL SOP Toggle its Display and Render flags on. This will be left as is for now, as you have not yet created any materials. Display and Render flags 2.5 CREATING THE HEAD 1. At the Top of the Tile layout window, change the editor menu from SOPs to Objects. 2. Place a new object node in the layout window name this node head change wireframe color to yellow 3. Pass the head object into its SOP editor. 4. Ensure that your viewport is set to view the SOP editor you are working in. If it is not, than change it by selecting the head object at the top of the viewport window. Houdini Training 4.0 Side Effects Software

12 Set to SOPs 5. Delete the default file SOP. SPHERE SOP NURBS Orientation X axis Radius XFORM SOP CARVE SOP Scale Rename lip_profile First U.365 Second U.501 Toggle Extract On CARVE SOP COPY SOP First U.34 Rename two_lip_curves Second U.521 # of Copies 2 Keep Outside Scale Do not keep Inside Toggle Prim numbers ON *Template this SOP for now SKIN SOP Note: By default, the Skin SOP has skinned all 4 curves in order ie: 0 to 1 1 to 2 and 2 to 3 creating one NURBS surface This is not what you want in this case. You actually want to create two surfaces by skinning curve 0 to 2 and then skinning curve 1 to 3. To do this without having to use multiple skin sops: Change the Skin parameter to Skip every N Primitives (where N is set to 2 by default) Skin now skips every 2nd primitives skinning curve 0 to 2 and then 1 to 3 creating two surfaces 12 Side Effects Software 1999 Houdini Training 4.0

13 . MERGE SOP Pipe the Carve SOP from the left hand network into the Merge as well as the Skin SOP from the right hand network. You can now toggle the Carve SOPs template flag Off. Toggle the display of Primitive numbers on, if they are not already showing. STITCH1 SOP Group 0 1 Do not toggle the Stitch option On quite yet. Instead pay particular attention to the red guide geometry. By default Stitch, is going to stitch the two surfaces components together in the U parametric direction, by stitching the U boundary curve of the first surface to the U boundary curve of the second surface. Obviously the U direction of the second surface component needs to be reversed. To do this: 1. Ensure that the Stitch SOPs display flag is toggled On and toggle to the viewport into Display SOP mode. 2. Insert a Primitive SOP between the Skin SOP and the Merge SOP. open the Face/Hull folder set the Vertex parameter to Swap U and V Houdini Training 4.0 Side Effects Software

14 3. Return to the Stitch SOP Toggle the Stitch option On in the Stitch SOP. The two surface edges are now stitched together. 4. Working with the Stitch SOP parameters: set the Bias parameter to 1 5. Toggle the viewport into Current SOP mode once again. Note that once the Stitching is done the Primitive numbers have changed. STITCH2 SOP 1. Group Interactively decrease the Left U parameter down to a value of 0 3. Toggle the Stitch Option On 4. Interactively decrease the Bias parameter down to a value of 0 Positioning the Head 1. Ensure the last Stitch SOPs display flag and render flags are toggled On. 2. Click on the See one/all objects button located at the bottom of the viewport window. Now you will see the Pot and Stem. 3. Press the 5 key to display all 4 view windows. 4. Home all view windows. 14 Side Effects Software 1999 Houdini Training 4.0

15 5. Select the head object to make it the active object. Working with its Transform folder Change its translate values to Transforming the Head in Object Space OR TRANSFORM INTERACTIVELY 1. Ensure that the Display and Render flags of the Stitch2 SOP are on. 2. Change the tile layout window to Object space. 3. Switch into Select Transform state. Remember the icon is located to the left of the viewport window. 4. Now that you are in the Select Transform state you can use the view window to interactively reposition the head in relation to the stem using the 4 view windows. Right click on the head object in any view window to select it without moving it. When selected the head object will appear hi-lited. If you use the left mouse button you will have to actually grab the geometry and reposition it. If you use the right mouse button you can interactively move the geometry without having to physically grab it. 5. Remember to toggle back into the default View State mode before continuing. Do not leave yourself in Select Transform state. 6. Press the 2 key to display only the perspective window once again. 7. Change the viewing state from Current SOP mode to display SOP mode. 8. At the top of the viewing window switch to view the Object editor. You will likely find that your World space translational parameters for the head are relatively close to the one that I used, In the interest of consistency. change the values in the Stem object translate folder: Transform Just to add some interest to his look, adjust the Rotate parameters in world space to: Rotate Good time to save your file again. Houdini Training 4.0 Side Effects Software

16 Head objects SOP network EDITING THE STEM TO MATE WITH THE HEAD 1. Select the Stem Object Node and enter back into the SOP editor. 2. Change the Viewport window to be the SOP editor, ensure that you are viewing the Stem objects SOP editor. 3. At this point you should be in Display View Mode If you are not, press the Show Display SOP button located at the top of the viewport window. 4. Toggle off the See one/all objects button, so that you are only viewing the Stem. 5. \ to insert a Group SOP between the Primitive SOP and the Align SOPs. Toggle its display flag On. GROUP SOP Group Name Stem_top Entity Points Number Enable option toggled On 16 Side Effects Software 1999 Houdini Training 4.0

17 Pattern Field set to 0-17 This will group the points at the top of the Stem. 6. Toggle on the See one/all Objects button located at the bottom of the interface to see the following translation in relation to the Head. TRANSFORM SOP Group Stem-top (so that only the points in the group are affected by the transformation) Pivot Rotate Toggle off the Display of primitive number if they are still toggled on. Houdini Training 4.0 Side Effects Software

18 2.6 CREATING THE INNER MOUTH 1. Change the Editor menu located at the top of the Tile layout window to be Objects. 2. Place a new geometry node in the layout window name this inner_mouth change wireframe color to red parent the Head object to the inner_mouth object node 3. \ on the inner_mouth object tile, and select Edit SOPs from the pop-up menu. 4. Change the viewport window to view the inner_mouth SOP editor. 5. Toggle off the See one/all Objects button. 6. Delete the default file SOP. OBJECT MERGE Source head two_lip_curves DELETE SOP Toggle on its Display flag Group 0 1 larger profile curves are deleted JOIN SOP Toggle on its Display flag Toggle the Multiplicity option on to retain hard edge. 18 Side Effects Software 1999 Houdini Training 4.0

19 SKIN SOP Ensure that the Skin SOPs display flag is toggled On. Inner mouth SOP network 2.7 CREATING THE LIPS 1. Switch the Tile layout window to the Objects editor. 2. Place a new geometry object node in the layout window name this node lips in the Misc folder, change the wireframe color to orange RGB parent the Head object to the lip object node 3. Click on the lip tiles pop-up menu. Select Edit SOPs to enter into its SOP editor. 4. Change the viewport window to view the lips SOP editor. 5. Delete the default file SOP. OBJECT MERGE Source head lip_profile JOIN SOP Defaults CIRCLE SOP NURBS Radius Houdini Training 4.0 Side Effects Software

20 SWEEP SOP SKIN Circle is Cross Sectional input Join is the Backbone input Toggle V wrap option On 1. Ensure that you are in Display SOP mode, and that you have the Display flag of the Skin SOP toggled on. 2. Select the Join SOP to display the associated parameters. decrease the Tolerance parameter to 0.25 to sharpen the corner at the join point 3. Insert a Primitive SOP between the Sweep SOP and the Skin SOP Group 4 5 (they are the two circles that make up the middle of the upper lip) toggle the Do Transformation option On increase the scale parameter to a value of Insert another Primitive SOP before the Skin SOP Group toggle the Do Transformation option On increase the scale parameter to a value of 2 REFINE SOP Append this SOP to the Skin SOP. Toggle the U option Off Toggle the V option On First V Second V 0.18 V Divisions 3 GROUP SOP Group Name Upper_lip_points 1. * Toggle the Group Sop s display flag On This is paramount to this routine working. 2. Entity points 3. Toggle the number enable option On. All points will become active. 20 Side Effects Software 1999 Houdini Training 4.0

21 4. Remove the * from the Pattern Input field No points are active any longer. 5. Toggle the interface into Select Transform State. Located to the right of the viewport window. Change the sub-state to select points. 6. Home the viewport window. 7. Using the left mouse button drag a bounding box over the points that define the curve you inserted with the refine sop. Only these points should be active at this point. 8. Click on the Transfer Selection to Pattern button in the Group SOP s parameter dialogue. 9. Remember to toggle back into the standard View State mode before continuing. Do not leave yourself in Select Transform state 10. Before continuing I want you to find the point number of the point at the back of the lips as indicated in the following illustration. 1) Toggle the display of point numbers on for only the active geometry. If you toggle the display of all points on the screen is simply to busy. 2) Jot down the number of the point shown in the illustration to the left. It is point 212 in this illustration. 3) Toggle the display of point numbers Off once again. Houdini Training 4.0 Side Effects Software

22 To toggle on the display of selected points, click on the parameter button located to the right of the viewport window the viewport window. In the parameter window click on the Point numbers button in the Selected area. TRANSFORM SOP Group Upper_lip_points You will now use a particularly powerful point expression to relocate the pivot point for the group of points to the proper location for the subsequent scaling of this point group. I wanted the pivot point to be located at the back side of the lip. Works like this: 1. [ Click on the Pivot field of the Transform SOP. This will now enable you to enter expression in the Pivots X Y and Z fields. Enter the following expression into the X Pivot parameter field. Of course if your point number was not 212 you will use the point number that you determined to be correct. point(../group1,212, P,0) 2. Copy and paste this expression to the Y and Z pivot parameters as well and then make the following edits. The P, 0 changes to P, 1 for Y and to P, 2 for Z So your expressions now read: point(../group1,212, P,0) point(../group1,212, P,1) point(../group1,212, P,2) 22 Side Effects Software 1999 Houdini Training 4.0

23 The pivot point is now translated to the exact location of point 212 on the X Y and Z axis. 3. Set the Scale parameters to Ensure that the Display and Render flags are toggled on, on the final xform1 SOP. The SOP network for the lips object 2.8 CREATING THE TEETH 1. Return to the Object Editor 2. Place a new geometry object in the layout window name this node teeth parent the Inner_mouth object to the teeth object node Houdini Training 4.0 Side Effects Software

24 3. Pass the teeth node into the SOP Editor 4. Change the viewport display to display the SOP network for the teeth object. 5. Delete the default file SOP The teeth for the plant will be a simple tube, reshaped into a come and then bent into somewhat of a hook shape using the Twist SOP. TUBE SOP Primitive Type NURBS Radius Height 0.5 Centre on X 0.15 (this simply moves the edge of the cone to 0 on the x axis to facilitate a mirror copy later) Open the Detail Folder Rows 4 Columns 4 V Order 4 Home the Viewport window at this point TWIST SOP Toggle on its Display flag. Operation Bend Primary Axis Z (the bend is going to occur primarily in the direction of the Z axis) Secondary Axis Y (the bend will also occur along the Y axis as well to a lesser extent) Rotate the viewport slightly about the Y axis to better visualize the effect on the tooth. 1. Interactively increase the Strength parameter to a value of 76 to effect the bend 2. Interactively increase the RollOff parameter to a value of 0.5 to re-align the base of the tooth to be parallel with the X axis once again. 24 Side Effects Software 1999 Houdini Training 4.0

25 COPY SOP ALIGN SOP Toggle on its Display flag # of Copies 16 Translate on X 0.2 Scale Toggle on its Display flag 1. Toggle the Individual alignment, translate and rotate options Off. 2. Interactively adjust only the Right U parameter to a value of Toggle the Translate parameter On 4. Toggle the Individual Alignment parameter On. 5. Adjust the bias parameter to 0 so that the string of teeth are aligned with 0 on the X axis once again simply to facilitate a mirror copy of this tooth string later. OBJECT MERGE SOP Source Head Skin1 Do not append this SOP to the current network chain. Simply place the SOP in the layout window. COPY SOP Number of Copies 2 Scale on X set to -1 The other scale parameters remain unchanged CREEP SOP 1. Click on the Initialize button and select the Keep Proportions option rotate on the X axis -90 You are actually rotating about the U parametric direction. Houdini Training 4.0 Side Effects Software

26 rotate on the Z axis -180 You are actually rotating about the W parametric direction translate on the Z axis -.45 You are actually translating along the W parametric direction translate on the Y axis.2 You are actually translating in the W parametric direction scale on the Z axis 2.65 You are actually scaling in the W parametric direction CREATING THE LOWER ROW OF TEETH That takes care of the upper row of teeth keeping everything procedurally linked. The lower row of teeth are a little tricky in the instructional set so you will want to follow along carefully. The Creep SOP only recognizes the first input surface. That is why it ignored the second surface. 1. Using the ] branch append a Delete SOP off of the Object Merge SOP and place it to the left of the current Creep SOP. Make sure this SOP is not inserted between the Object Merge and the Creep SOP. 2. Toggle the Delete SOP s display flag On and delete primitive number 0, the top surface. 3. Make sure the Creep SOP is the currently active SOP and use the Ac command to copy it. 4. Use the Av command to paste the Creep SOP and place this copy under the Delete SOP. You now have a Creep2. 26 Side Effects Software 1999 Houdini Training 4.0

27 5. Pipe the output of the Delete1 SOP into the right input node of the Creep SOP as it s path input. 6. Toggle the Creep2 SOP s display flag On. All is well except that the teeth are being crept to the wrong side of the path surface. To correct this: 7. Insert a Primitive SOP between the Delete SOP and the Creep SOP and working in the Face/Hull folder: change the Vertex option to Reverse U. 8. Append a final Merge SOP to the network chain and ensure that both Creep SOPs are piped into the merge for display. 9. Don t forget to toggle the Merge SOPs display and render flags On. Problem: The back teeth are intersecting with each other. There are several solutions to this problem. One is expensive dental surgery. The other much easier. 10. Toggle the Copy1 SOP on to make it active. (this is the copy SOP that made 16 teeth out of 1) You can keep the Display flag of the final Merge SOP on to see the changes as they filter down the SOP network. Houdini Training 4.0 Side Effects Software

28 11. Reduce the number of copies to 13...problem solved!!! SOP network for the teeth object. 2.9 CREATING THE CROWN OF LEAVES 1. Return to the Object Editor 2. Place a new geometry object node in the layout window name this object crown parent the Head object to the crown object node In its Misc folder, set the wireframe display color to Green. 3. Pass the crown node into the SOP Editor 4. Change the viewport window to be in the crowns SOP editor. 5. Working with the default File SOP. 28 Side Effects Software 1999 Houdini Training 4.0

29 FILE SOP 1. Navigate to the file crownleaf.bgeo Home the viewport window COPY SOP Toggle on its Display flag # of Copies 15 Translate on X 0.5 Home the viewport window GROUP SOP Toggle on its Display flag Number Enable Operation Group by Range Note that the range is conveniently set to Start at primitive 0 end at Primitive 14 and to select every other primitive 1. Now go back up to the Copy SOP and set the Translate parameter for the X axis back to 0. It was only increased initially so that you could easily visualize how the group SOP was processing the geometry. XFORM SOP Group Group 1 Houdini Training 4.0 Side Effects Software

30 Scale * Starting a new SOP Chain OBJECT MERGE Source head xform1 CARVE SOP First U 0.25 Second U 0.75 Toggle on Extract JOIN SOP 1. Toggle the Object Merge SOPs template flag On so you can visualize the head for placement of the crown of leaves. ALIGN SOP This SOP is appended to the Copy SOP that creates the string of leaves 1. Pipe the Join SOP into the right hand input node to be used as the Auxiliary Source. 2. Toggle the Individual alignment, translate and rotate options Off. 3. Toggle the Translate parameter ON 4. Interactively increase the bias parameter to a value of Interactively increase the Left U parameter to a value of Toggle the Rotate option On 7. Toggle the Individual Alignment option On. 8. Open the Transform Folder interactively adjust the Translate Z parameter to a value of -0.8 interactively adjust the Rotate X parameter to a value of -40 interactively adjust the Translate Y parameter to a value of Side Effects Software 1999 Houdini Training 4.0

31 interactively adjust the Rotate Z parameter to a value of Ensure the Align SOP s display flag is currently toggled On. crown objects SOP network Houdini Training 4.0 Side Effects Software

32 2.10 ADDING SOME CONTROL NULLS 1. Return to the Object Editor and ensure that all objects are being displayed properly. If they are not, enter into the appropriate SOP networks and toggle On the applicable display flags. 2. Change the viewport to display Object space. NULL1 Add a Null object to the layout window name this null Pot_stem parent this null to the Pot Object node and the Stem object node NULL2 Add a Null object to the layout window name this null Flower_head parent this null to the Head Object node NULL3 Add a Null object to the layout window name this null Complete_plant parent this null to the Pot_stem null and the Flower_head null Translate Scale 1.25 (this is the Uniform scale parameter) 32 Side Effects Software 1999 Houdini Training 4.0

33 Miscellaneous 2.11 USING THE OPREAD COMMAND To the students In the interest of time, the bird cage was saved out as a component from a completed file using the opwrite command. The object nodes to write out were named null1, feathers cage and support. Using textport commands, this is how that was done. opcf /obj opwrite /obj/null1 feathers cage support /[working directory]/import1.hip 1. In the main viewport window, change it to Texport. 2. You will now read this geometry into the current file using the opread command. In the texport use the following commands. opcf /obj opread /[current directory where training files are stored]/ import1.hip If you have a lot of operators to write out it is easier to assemble them into a group Edit > Edit Obj Groups. Assuming I had created an object group called head; opwrite /obj/@head /[working directory]/import1.hip 1 MISCELLANEOUS SOIL OBJECT MERGE SOP The pot currently has no bottom, nor has it soil. Consequently the plant appears that it is floating in the air. SO: 1. Return the viewport from Textport to Viewer. 2. Add a new geometry object. Rename it to Soil Parent the Pot object to the Soil object. Enter into the Soil objects SOP editor. Change the Main viewport to be the Soil Objects SOP editor. Delete the Default File SOP. Source 1 Pot Houdini Training 4.0 Side Effects Software

34 Miscellaneous SOP Display SOP FACET SOP Toggle on its DIsplay flag In the Consolidate field change it to Consolidate Points Fast CONVERT SOP Change the Convert to field to If you toggle on the information button of the Convert SOP, you will notice that you have 2 mesh surfaces. One is a partial section of the Pot object. You want to carve out a curve out of the inner part of the Pot. You will then Skin that to make a surface based on the area of the Pot. First you have to delete the extraneous surface. DELETE SOP Group 1 CARVE SOP Toggle on its DIsplay flag First U 0.15 SKIN SOP Toggle on its Display flag Leave it at its defaults CONVERT SOP Display flag on Convert To NURBS Surface TRANSFORM SOP Scale FRACTAL SOP Toggle on its Display and Render flags 34 Side Effects Software 1999 Houdini Training 4.0

35 Some Evil Eyes? Change the Direction to Increase the Divisions to 3 Decrease the Smoothness value to 0.45 Decrease the Scale parameter down to 0.07 Change the main viewport window to view Object space. Now the Plant is looking more complete...how about some eyes? Have you saved lately? 1 SOME EVIL EYES? CREATING THE EYE SOCKET In the Tile layout window navigate up to the Object editor Keyboard Shortcut: (the u key will do this) Place a new node in the Object Tile layout window and rename it: eyes Enter into its SOP editor Keyboard shortcut: (the i key will do this) Houdini Training 4.0 Side Effects Software

36 Some Evil Eyes? Delete the default File SOP Change the main viewport window to be viewing the eyes SOP editor. *** Ensure the viewport display mode is set to Display SOP SPHERE SOP Primitive Type NURBS Orientation X axis Radius TRANSFORM SOP Rotate CARVE1 Toggle on its DIpslay flag First U Second U While displaying the output of the Carve SOP, select the Transform SOP and adjust the rotate parameter for the X axis to a value of Side Effects Software 1999 Houdini Training 4.0

37 Some Evil Eyes? TWIST SOP Toggle on its Display flag Home the viewport window Strength 18 This simply gives the eyes some character and makes them look a little more sinister. TRANSFORM SOP Toggle on its Display flag Translate Rotate COPY SOP Display Flag # of copies 2 scale PRIMITIVE SOP Display Flag 1. Open the Attributes Folder. 2. Change Keep Color to Add Color. 3. Delete the current color channel (T \ on the color field button). Select Delete Channels Houdini Training 4.0 Side Effects Software

38 Some Evil Eyes? 4. Set the color parameters to ANIMATING THE CARVE SOP TO CREATE A BLINK 1. While displaying the output of the Primitive SOP, select the Carve SOP to display its associated parameters. 2. [ on the First U field to enable you to enter expressions. Enter the following expression in the Parameter field: abs(cos($f*5))*.2 3. Playback the animation at this point, and although the eyes will blink, there is an obvious problem. Essentially the blink is backwards. Or is it. It simply depends on the effect you want to achieve. However, assuming that you want the upper eyelid animated rather than the lower eyelid: 4. Select the Xform1 SOP to display its associated parameters and: Rotate the geometry about the Z axes. (set the Z Rotate parameter to 180) The upper eyelid now closes down as you might have expected. 38 Side Effects Software 1999 Houdini Training 4.0

39 Some Evil Eyes? 1.1 CREATING THE EYE BALL 1. Select the Copy1 SOP ensuring it is the only currently active SOP. 2. Using the Right mouse button click on the SOP s pictorial icon and choose the option Select inputs from the associated pop-up menu. At this point all SOPs in the chain above the Copy SOP should be active. 3. Use the Ac keyboard combination to copy the selected SOPs. 4. Use the Av keyboard combination to paste the SOPs. Move this new chain of SOPs over to the right of the current chain of SOPs. 5. Select the Carve2 SOP to display its associated parameters and: toggle the Keep Inside option Off toggle the Keep Outside option On You now have the opposite Carve geometry which represents the eye balls themselves. MERGE1 Place a Merge SOP beneath the two chains Toggle its Display flag on Pipe the Primitive SOP into the Merge1 SOP. Pipe the Copy2 SOP into the Merge SOP 1. Play back the animation at this point. (Try it is shaded mode) 2. Return to frame 1. Houdini Training 4.0 Side Effects Software

40 Some Evil Eyes? 1.2 CREATING THE PUPILS The SOP chain that you copied earlier is still in the copy buffer, therefore: 1. Use the Av keyboard combination to copy this SOP chain once again and move the chain over to the right of the last chain. 2. Toggle the Copy3 SOPs display flag On. 3. Select the Carve3 SOP to display its associated parameters and: toggle the Keep Inside option Off toggle the Keep Outside option On 4. Using the Right mouse button, insert another Carve SOP between the existing Carve3 SOP and the Twist SOP. Working with this new Carve SOP: Toggle the First U option Off Toggle the First V option On and set the parameter to a value of Toggle the Second V option ON and set the parameter to value of Toggle on the Display flag of the final Merge SOP. Connect the output of the Copy3 SOP (the last SOP in this chain) to the Merge SOP for final display and toggle the display into Shaded Mode. 6. Insert a Primitive SOP between the Copy3 SOP and the Merge SOP and working with the Primitive SOP parameters: open the attributes folder set the option to Add Color delete the current Color Attribute channel set the color parameters to to create a set of black pupils You will likely encounter some bleed through shading of the eyeball surface on the pupil surface. This is due to the fact that both of these surface currently occupy the same shading space. To correct this, the pupil surface must be offset very slightly from the eye ball surface. To do this easily: 7. Return to the Transform folder of the Primitive SOP: toggle the Do Transformation button On set the Translate parameter for the Z axis to a value of Side Effects Software 1999 Houdini Training 4.0

41 Some Evil Eyes? It will be up to you to decide how the eyes can be positioned on the top of the plant. Don t forget to save your file again if you have not been doing so. Houdini Training 4.0 Side Effects Software

42 Appendix 1 APPENDIX If you don t have the geo file for the pot profile you can easily construct it from these directions. 1. Pass the Model SOP into the modeller. But rather then trying to open the geo file that you don t have Set up to create a Polygon Curve. 3. Place 7 points in somewhat of a straight line in the front window. It doesn t matter where the points are. Simply place 7 points in the front window. 4. Display the Geometry Spreadsheet. This is done by selecting Geometry spreadsheet from any one of the viewport selection menus. 5. Working with the geometry spreadsheet relocate the points to the following coordinates on x y and z respectively: Point Point Point Point Point Point Point Side Effects Software 1999 Houdini Training 4.0

43 Appendix 1.1 A FINAL WORD The Primitive SOP is very versatile and can be used very effectively to move the Pivot point to the centroid of the Primitive input to it as you saw in this exercise. However, there are times when the input to the Primitive SOP will be more than one single primitive. When multiple primitives are being passed to the Primitive SOP, the SOP addresses each of the Primitives individually and thus each primitive rotates around its own local centroid. (Using Rotate as an example of course) Default Grid SOP Toggle on Unique Points Rotate on Y -50 To address the centroid of the entire set of Primitive being passed to the Primitive SOP use a bbox expression. Of course, one could use a Transform SOP instead. Enter these expressions in the Pivot X Y Z fields For X (bbox(../facet1,d_xmin)+bbox(../facet1,d_xmax))/2 For Y (bbox(../facet1,d_ymin)+bbox(../facet1,d_ymax))/2 For Z (bbox(../facet1,d_zmin)+bbox(../facet1,d_zmax))/2 Save these expressions as a Preset and consider using a SOP name such as Centroid rather than the name facet1 used here. Then whenever you want this functionality recall the preset to the Primitive SOP and simply rename the SOP that the passing the Primitives to the SOP to be Centroid. Houdini Training 4.0 Side Effects Software

44 Appendix 44 Side Effects Software 1999 Houdini Training 4.0