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lModelling and Lighting a Disco Mirrorball

1. Open/reset max and change the display units and system units to centimeters/1 unit = 1cm by going to the customise menu and choosing 'Units Setup...'



2. Open the Material Editor, then create a new 'Multi-sub Object'.
Set the material to have 2 sub-materials by clicking 'Set Number'.
Name the first one 'Mirror' and the second one 'Black'
Click the colour swatch to the right of the second material and set it to pure black (this is a short cut for changing the diffuse colour for that material)


3. Next, click the material in the first slot and change it to a 'Raytrace' material.
Change the diffuse colour to black.
Change the 'Specular Level' value to something like 180
Change the 'Glossiness' value to something like 70


4. Click the small grey square next to 'Reflection' and choose 'Falloff'
Change the top colour swatch to a light grey (roughly 180 for all color values)
Change the 'Falloff Type' to 'Fresnel'
Click the 'go to parent' button twice to go back to the top level of the material again.


5. In either the perspective or orthographic (user) viewport create a sphere primitive.
Go to the Modify Panel and change the radius to 30.0cm and the segments to 62.

That specific segments value gives you a face exactly halfway down the side of the sphere and at 90° to the pivot point (This is shown in the image below as the home grid line is going right through the middle of it. This is helpful for the next few stages.


6. Convert the sphere to an editable poly, go into polygon sub-object mode and select that face mentioned jsut now (see image below)
Then click 'Detach' down the modify panel and use the settings shown below (note the change of name to 'tile_01')


7. Get out of polygon sub-object mode, and select the newly detached face, go into polygon sub-object mode for that object and extrude the face by 0.5cm.


8a. Exit polygon mode and give the object a contrasting object colour by clicking the colour swatch next to the objet name in the modifiy panel. This will help you in the next few stages.
Hit Ctrl+V to clone the extruded object to an 'Instance' and call it tile_02


8b. Change the 'Reference Coordinate System' to local ' and the 'User Pivot Point Center' to 'Use Pivot Point Center' Using angle snap rotate the cloned object up 90° so it sits on the top of the sphere.


9. Select tile_01 again and go tools-->Array.
Click the big 'Preview' button (this previews the effects of the array in the viewport before they are set')
Click the right arrow next to 'Rotate' and change the Y value to 90°
Change the 1D Count value to 15 and click OK
You should now see a line of new tiles arcing up towards the top tile.


10. Re-select tile_01 and go Tools-->Array once more.
This time turn on preview and zero the Y rotate value and put 360° in the Z value.
Now increase the 1D Count value until the tiles almost touch, I found a value of 61 works well here.
Click 'OK'.


11. Select the next tile up and repeat stage 10 but reducing the 1D count value so the tile dont intersect.
Keep doing this for all the remaining tiles reducing the tile count each time to compentsate for the reduction in space.






12. Due the process we just did, there is a very straight line of tiles that doesnt look right, we'll now change that.


13. Go to the 'Front' view and freeze the sphere object under all the tiles.


14. Select the second row up of tiles and give them a random rotation value to offset the start of that straight lline of tiles. Then repeat for the remaining rows (excluding the last (top) row as that only has four tiles and needs to line up with the very top tile)




15. Now select all the tiles apart from the lowest row


16. Using 'Mirror' choose the settings below to make a complete copy of the tiles and mirror them to finish the underside of the mirrorball.


17. Right Click and choose 'Unfreeze All'


18. Select all the objects and open the 'Collapse' utility in the 'Utilities' panel
You may need to find it in the extra list after clicking the 'More..' button.
Click 'Collapse Selected'
this collapses all the objects into one single object and is a quick way of using 'attach'. Its turns the objects into one single editable mesh.




19. Now go into polygon mode and hit Ctrl+A to select all the polygons.
Then go down the modifiy panel and enter '1' in the 'Set ID' box in the 'Surface Properties' rollout. this gives all faces a material ID of '1'


20. Add a 'Vol. Select' modifier to the ball.
Set the 'Stack Selection Level' to 'Face'
Set the 'Selection Type' to 'Crossing'
Set the 'Select by' option to 'Sphere'

Now you should see all the faces apart from the outer faces selected.
(if not you need to click the modifier itself to turn it yellow then use the scale tool to resize the gizmo until the selection matches the image below.


21. Now add a 'Material' modifier and change the value to '2'. This gives only the previously selected faces a Material ID of '2'

22. Now jsut apply the previously made material to the ball, the mirros material will apply to the outer faces and the black material will apply to the inner and side faces.
The modelling and texturing of the mirrorball is now complete.

Next up, the setting up the reflected light dots...

23. Create a box (using the 'keyboard entry' section in the create panel (after choosing the box primitive) at 1000cm x 1000cm x 350cm and at 0,0,0 coords.
This will act as the room for the dots to be cast on to.


24. Add a 'Normal' modifier to turn the box inside out and move it down so the mirror ball goes near the top of the room.


25. Set up your perspective view then hit Ctrl+C to create a camera in the same position.


26. In the top view create a spotlight roughly 90° to the camera.
Right click the right and choose 'Select Light Target'


27. Align this light target to the dead center of the mirrorball using the 'Align' tool


28. Right click the light target and choose 'Select Light' then go down the modifiy panel and reduce the 'Falloff/Field value in the 'Spotlight Parameters' rollout until the outer cone goes a tiny bit smaller than the mirrorball. this ensures the light wont be casting a sillouette of the mirrorball on the opposite wall.


29. Move the height of the light to near the top of the room
NOTE: You must make sure the light object is completely housed inside the cube as it will throw up errors later if it is outside the walls.


30. create an Omni light in the middle of the room for some ambient light.


31. Change the renderer to Mental Ray. to do this open the render Scene window (F10) and follow the image below


32. If you render now you should notice that there are no little light dots. This is because 'caustics' is turned off by default.


33. To turn 'Caustics' on open the Render Scene dialogue once again (F10) and enable 'Caustics in the 'Indirect Illumination tab'


34. Now select the Mirroball object, Right Click-->properties-->'mental ray' tab and tick the 'Generate Caustics' box. Click 'OK'


35. Now render, see any difference? you wont see much, I found one small dot so we know its doing something, just not much.


36. The fact is, the caustics are being generated they are just not bright enough to see properly. So select the light, find the 'mental ray Indirect Illumination' rollout and increase the 'Energy' value to 300.


37. Render again.

that's better!


However if you render a larger version you will see the dots are in fact made up of lots a small circular dots and there aren't really enough of them.

These dots are called 'photons' and are basically rays of light fired out fo the light object until they hit an object and light it up.


38. With the light selected now increase the Caustic photons value to '10' and re-render.


Looking better now.


39. Now this is fine for the resolution we are rendering at but if you want those slight squares to be a bit sharper you do the following...

Open the Indirect Illumination tab again the Render Scene dialogue (F10) and tick the 'Maximum Sampling Radius' box to enable it. This stops the photons from being over 1.0cm in size. Due to this size limit you will need to increase the amount of photons to fill the same space. So do the same as stage 38 but go up to 30 or so (or whatever is needed). This will increase render times to dont go crazy)


Much clearer and sharper but takes longer to calculate.




That's it!

You can then go mad and have multiple lights and change their colour for a good party atmosphere.

Here's a video I did to show the effect in motion.

MIRRORBALL VIDEO

I hope this tutorial was useful for you.