step 1: i used Adobe Illustrator todo create the curve for the outline of the bulb itself. I could have taken a photo of a lightbulb, but being lazy, y used google image Finder todo locate one from the internet. A quick trip th rouge Photoshop straightened the image up, and i placed the photo into Illustrator todo use as a guide. Here i have placed a guide th rouge the center of the photo, and have drawn a Bézier curve around the Glass portion of the bulb. You could Simply use the Bézier curve tools in Cinema 4D todo do this, but the next couple of steps Will show you why i choose not todo.
step 2: i gave the curve i drew thickness by increasing the stroke value. In this example i used 3 points so that the effect would be visible in this tutorial. In practice, the real thickness of a lightbulb Glass would be 1 point or less. Once i am happy with the curve, y choose object/Path/outline stroke. This turns my single line Bézier into a precise width double line – Something extremely dificult todo do with Cinema 4D Bézier curve tools.
Zom in and make sure that the curve hits the guideline at the top, and the two points there are lined up with the guide exactly.
step 3: select the line segment joining the two points at the bottom of the curve, and deleete it. We Will be drawing more of the Glass at this point.
step 4: Compleete the curve for the Glass. Youll have todo sort of Wing it, using the photo as a guide. In the example here i pretty much ignored the details in the photograph and created a column inside the Glass for the wires todo attach todo. Every make of lightbulb is slightly diferent so you can use some artistic license here. Make sure the end points line up on the guide exactly. Press Control-r todo make the rulers visible (if they are not already visible). In the upper left corder of the ruler you Will se todo crossed dotted lines. This is the zero point of the ruler. By clicking and dragging on those lines, you can reposition where the zero, or origin point, of your drawing is. Now, drag the zero point on the rulers down todo the bottom point of your Glass curve so that the origin sits there exactly. This point Will now be positioned at 0,0,0 when this curve is imported into Cinema 4D. Remove the guide line (important.) and the bulb image, and save the curve out as an Illustrator eps file, versión 6.0, no preview, no thumbnail.
step 5: now we are ready todo start in Cinema 4D. Create a new material, and place your lightbulb template image in the color channel. Take note of the píxel dimensions of the image. Create a plane object, orientation in -z and make the width and height of the plane object todo be the same as the píxel dimensions of your template image. Apply the material todo the plane. Set the material transparency todo on, and the plane object Will Ghost back, which Will make it easier todo se your work as you go. Pull the plane back in z a bit todo give you rom todo work on the bulb as you create it. Go todo the object Hierarchy and add a display tag todo this object. Tick of the use box on the first tag attribute, and change the display mode todo Gouraud Shading. This Will allow it todo be visible in the various views.
step 6: from the file menú, merge the curve you created in Illustrator. First step is todo switch todo axis mode, and reposition the axis point todo a world value of 0 in x. Hit f4 todo switch todo front projection, and then switch back todo object mode todo position/scale the curve till it matches up with the template image. Since we were careful todo position the zero point at the Edge of the curve in Adobe Illustrator, you should only ned todo position the object in the y axis only, and scale it todo fit the template. Its important that the right most points of the curve remain at a world value of 0 in x.
step 7: switch todo point mode, and click the topmost point of the curve, and right click todo bring up the contextual menú. Chose set first point. Go todo the curve attributes and turn of close curve, what should happen is that the curve Will have no connecting segment between the two points at the top of the curve. Add a lathe object todo the scene, and parent it todo the curve.
step 8: add a cylinder object todo the scene, with the following attributes: Radius and height todo line up with your template as shown above, 18 height segments (if you follow along the tutorial you Will se later that this value should have ben 14 height segments but its sometimes valuable todo se how todo fix mistakes later), 8 rotation segments, and 1 Cap segment. Once its positioned and sized correctly click the make editable icon, and switch todo point mode.
step 9: this is the part where you Will be scratching your head trying todo figure out how this series of steps results in the screw hilos of the base. I am not sure i understand it myself. But it works. Chose the rectangle selection tool, turn of only select visble elements in the active tool properties, and while holding down the shift key, select every fourth row of points in the cylinder, making sure todo not select the first or last row. Move these points some small amount in the x direction – I used 5 units in this tutorial.
step 10: select the next set of rows up, chosing every fourth row but do not select the top row of points. Move these points 5 units in the z direction.
step 11: select the third set of row (shown above) and move them -5 units in x.
step 12: select the fourth sets of rows (shown above) and move them -5 units in z. The second picture shows the results from the top view.
step 13: add a Hypernurbs object todo the scene, and child your cylinder todo it. You should se that it now has formed the shape of screw hilos. Hit f1 todo switch todo perspective view, and orient your view so that you can se the bottom polys of the cylinder. Switch todo poly mode, and then choose the live selection tool (pointer). Make sure that only select visble elements is ticked of in the acitve tool pane. Select the 8 polys at the bottom of the cylinder (as shown above).
step 14: using the bevel tool (right click todo choose it from the contextual menú) bevel these polys downwards twice as shown here. Once moving the polys a Little ways, and then again farther todo belly the shape down todo line up with the template image. We do the first smaller bevel in order todo create a row of polys that Will hold a sharper Edge where the screw hilos end.
Using extrude inner, pull the polys in a small distance. Then extrude inner again a very small amount todo create a small ring of polys. Again this is todo add detail holding Edges todo the Hypernurbs Cage. Extrude the polys a small amount downwards. What we are doing here is forming the área where the insulator on the base starts.
Bevel the polys again and then pull up on the green axis arrow todo move the polys upwards slightly. This makes the bevel become more shallow. Bevel downwards again, then extrude inner a small ways, then extrude down a small ways and finally extrude inner again. The result you are aiming for is shown above. What this series of steps does is model the insulator and the small buttonconnector on the bottom of the light bulb.
step 15: return todo point mode and the front view. Make sure no points are selected. Go todo the structure menú and choose optimize, and ok the small dialog that pops up. This Will make sure the caps of our cylinder are welded todo rest of it, which Will allow the Hypernurbs object todo do its work. Now, using the rectangle selection tool, and making sure only select visible elements is turned of in the active tool selection, Grab the row of points that represents your first bevel and pull them up in y (as shown above). This Will reinforce the Edge there.
step 16: switch todo poly mode, and pick the live selection tool. Make sure only select visible elements is turned of in the active tool pane, and in the front view, drag select across the line that bisects the insulator área todo select the two rows of polys there. Then go todo the selection menú, and pick grow selection. The highlighted polys should now include the small inset polys at the Edges of the insulator área. Go todo the selection menú, and choose set selection. The poly object in the heirarchy should now have a small triangle tag. Select it, go todo the attributes tag, and click the basic button. Change the name from polygon selection todo insulator. This Will help us with texturing the object later. Now click on the object in the heirarchy todo deselect the triangle tag (very important).
step 17: using the live selection tool, and making sure only select visible elements is turned on in the active tool pane, select the 8 polys at the top of the cylinder.
step 18: with a series of bevels, bowl the shape outwards todo Conform todo the bottom of the bulb object. Extrude inner *outwards* once, then extrude up once todo form a small lip at the top edge. Now, deleete the polys at the top of the object.
Now, if we look at the shape that has ben created, its a bit wrong. The área where the screw hilos are appears todo be todo narrow. This is common with Hypernurbs modelled objects – The object tends todo Shrink inside of the poly Cage that defines it. We also have todo Many rows of screw hilo. Well fix these problems in the next step.
step 19: over all fixes: switch todo point mode and select all the points in the object below the top lip you formed, and pick the scale tool. Click the y axis icon on your toolbar so that you Will be scaling in x and z only, and scale the object todo more closely Conform todo the template image, as sen above.
Now todo fix the screw hilo. Using the rectangle selection tool, and making sure only select visible elements is of in the active tool pane, select four rows of thread polys and deleete them. Go todo the structure menú and optimize todo clean up the points that are left behind. Now, switch todo point mode and click on one of the points at the top Edge of the missing row, and note its y value. Click on the point opposite at the bottom of the missing row, and note its y value. Subtract the two values todo arrive at a diference value. Now, select all the points at the top part of the object. You Will se an averaged y value in the coordinates pane. Subtract your diference value from this, and type the new value in and hit apply. The top part of the object should move down into the Gap. Now go todo the structure menú and optimize todo weld the Edges together.
With a row of screw hilos removed, the object is now a bit todo short. Chose the scale tool, and by dragging on the green y axis, scale the now shorter object up so that its at the right vertical size again. Reposition it in y todo line up with your template image. At this point everything should be looking pretty close todo the final geometry and we are ready todo texture the object.
step 20: create Glass and metal textures and apply them todo the bulb and cylinder objects respectively. Create an insulator texture, and apply that todo the cylinder object as well. In the texture attributes tag, type insulator into the selection and the texture Will be restricted todo only the insulator polys we defined earlier. I decided i wanted another texture on the button área, so i went back into poly mode, and using the live selection tool with only select visible objects turned on in the active tool pane, y selected the 8 polys at the bottom of the object. Then i used grow selection from the selection menú twice todo select all the polys that make up the button. Set selection from the selection menú should make a second triangle tag appear on the cylinder object. Select that tag, and in its basic tag properties, change its name todo button. Make a brass texture, and apply that todo the cylnder. In the selection área of the texture attributes tag, type button and the texture Will be resticted todo that selection (shown above).
step 21: in the front view, add a Spline object, and switch todo point mode, using the Control key, draw a Spline down the wire inside the bulb. Add a Spline primitive – Circle todo the scene. Set the circle Radius todo 1.
Add a swep Nurbs object todo the scene and nest the Spline and the circle in it as shown above. They must appear in this order – If everything goes right, the Spline Path Will turn into a Thin pipe. Using a similar technique model the other wire, and the filament.
step 22: you can further edit the wire Splines todo form Little loops todo hold the filament. I choose todo create a coiled filament here using the following steps: i created the Spline Path for the filament using a Spline object and drawing the Path just like for the wire supports. In the Spline attributes, y changed its intermediate points value from adaptive todo uniform, and changed the number value todo 180. I added a Spline primitive circle todo the scene and set its Radius todo.5 units. I clicked the make editable icon todo convert it into an editable Spline object. I added a swep Nurbs object todo the scene, and nested the filament Path and circle todo it, just like shown above for the wires. Now todo make it coil like a Spring: in the swep Nurbs attributes, y changed the rotation parameter todo 19000. Select the circle Spline nested under it, and go todo axis mode. In the coordinates pane, set the pitch rotation of the axis todo -90 and the x position todo 1.25. Voila, a coiled filament.
step 23: some texture and setup finesse steps later, you Will have a very realistic looking lighbulb object, suitable for framing. If you are going todo use this object in another scene, youll probably want todo add a null object and nest all the sub objects created in this tutorial inside of it.
James Hastings-trew.