3D Studio VIZ R3 - T2 - Materials

Learning VIZ	Stephen Peter, S.Peter@unsw.edu.au
Introduction	Image from model by Sook Hwai LEE.

	This tutorial will introduce Materials. You will open an existing model and then add materials to the objects. Once you've logged-on start 3D Studio VIZ.
Open Sesame
If you don't have access to "Resources on Emuwater" - that is, if you're not at UNSW - right-click on the link tut2.max and save the file.	Select Open… from the File menu, change the drive to Resources on 'Emuwater' (R:), then choose Samples, benv, & 3D Studio VIZ, finally select tut2.max and click on Open. Once you've opened the file, save it, using File - Save As...!!
There is a proverb that goes something like "risk only what you can afford to loose" - it has many meanings ranging from Love to Money, but it also applies to using computers!!! VIZ has an "autosave" setting and I suggest that you use it! From the Tools menu, select Options... and the click on the Files tab. In the File Handling section make sure Increment on Save is checked. In the AutoBackup section set Backup Interval to 5 minutes. The autosave files are stored in VIZ's backups folder: C:\Program Files\3DSVIZ3\AutoBack. If VIZ crashes, copy the most recent file into your account and rename the file - make sure to change the extension from .mx to .max	This file contains an almost complete model of a simple interior; but, as you can see, without the proper materials it doesn't look like much!
	Figure 1     Plan.
Let there be Light...
	Before we add the materials we must first put some lights in the space!
General Lighting	Firstly, we'll put general lighting (which we won't put into light fittings!) and then we'll place some wall lights.
	Select the Lights icon on the Create command panel and choose Omni, using the Top viewport, pick a point in the middle of the dining room. VIZ will place the light with a Z (height) value of 0, so you'll need to use the Select and Move (in the Front or Left view) to move the light to the height you want (just below the ceiling).
	You'll need to set some of the parameters: in the Modify command panel, in the Attenuation Parameters rollout set Far Start value to 3500 and End value to 5000 and tick the Use checkbox under Far. In the Shadow Parameter rollout, make sure On is ticked.
Use Instance each time you copy the light!	Next, using the Top view, click on Select and Move (if it's not IN) then (while holding the Shift key down) drag the light into the middle of the kitchen and choose Instance when prompted. This creates an exact copy of the previous light - if you alter the parameters of either light, the other's parameters are also changed. Now copy the light into the living room twice (once at each end). Then into the middle, to the right of the steps.
Wall Lights	If you look carefully, you'll see a number of yellow blobs on the walls, these are light shades. Put an omni light in one of these light shades - it will require a bit of fiddling to get it inside the shade. Set the Far attenuation to start at 80 and end at 2000, and check that shadows are turned ON.
Check the position by zooming-in in both the Top and Front (or Left) views to make sure the light is inside the shade.
	Then (instance) copy the omni light into the other wall mounted light shades! Once you've instanced the lights, zoom in to check the lights are centred inside the shade. You should only need to check in the top view because the height will remain constant - unless you change it...
We live in a Material world
To assign a material to an object, select the object, select the material, and then click on "Assign Material to Selection".	Now, the fun begins! Click on the Material Editor (towards the top-right). You'll see a group of coloured spheres at the top and a swag of parameters down the bottom! Click on the sphere at the top-left, VIZ will draw a border around it (if it wasn't already there).
Press the Select button after picking the group.	Click on Select by Name (from VIZ's main toolbar, not the material editor), then select [West Walls] - objects can be grouped (for easy selection) by using the "Group" command.
	Click on Assign Material to Selection, hopefully the border on the sample sphere will change to include filled triangles at each corner - this is how VIZ displays materials that have been assigned to objects.
	In the Blinn Basic Parameters rollout, click on the sample colour (dull red) beside the Diffuse label. VIZ will display a colour selector: on the left is a rainbow pattern labelled "Hue" (colour), beside it is the "whiteness" and to the right are Red, Green, Blue and Hue, Saturation, Value sliders. Click in the "whiteness" section down near the bottom - to choose a whitish colour, then click close.
	This process has assigned a "flat" colour to an object.
Use the Shift key to select adjoining items or the Ctrl key to select non-adjoining items.	Use Select by Name to select the [North Walls] and [South Walls] and then assign the first material to them also.
Glass	Click on the second sample sphere and then pick Get Material. In the Browse From: section choose Mtl Library. Scroll down through the list until you find Glasss-Clear (Standard) and then double-click it - this changes the parameters of the second sample to be this material (glass). Dismiss the material browser once you've chosen the glass.
Hold the Ctrl key to add the second selection.	Use Select by Name again to select [Balcony Glass] and [Glass], then click on Assign Material to Selection.
	Now that the windows are Glass it would be possible to rotate the perspective view so that you're looking into the space - from the "east" - and then render the view...
	Before continuing, it would probably be a good idea to save what you've done!
Timber	Click on the third material sample and then Get Material. From the bottom of the list select Wood Cedar Boards (Standard). Use Select by Name to select living room floor and [Hall Floor]. Once you've selected the floor, go back to the Material Editor and select Assign Material to Selection to make the floor timber.
Cameras
	To really get the idea about how a space may look, you need to get inside the space(!) and to do that you need to create cameras!
These views show the suggested location of the camera. This position gives a good view of the timber floor in the living room. Top View Right View
	To insert a camera, click on the Camera icon in the Create command panel and click on the Target button. Move the cursor (in the Top view) to where you'd like the camera and then drag in the direction that you want the camera to look. You should notice (in the Front or Left views) that the camera is "sitting on the floor" and looking along the floor!
	Click on Select and Move then move the camera and target point up - be careful that the cursor is the "move" cursor (which looks like a cross with arrows on each arm).
This technique can be used to change any of the views, for example you can change the Front view into a Back view!	Once you've set both positions, Right-Click on the label of the Perspective view, choose Views and then Camera01. This will change the perspective view into a camera view. Render the Camera01 view!
Scaling Materials
	The timber, as it is, appears too large when rendered, so we need to scale the material! To do this correctly, you need to study the material to determine its "size" and base the scaling on that information.
	Bring up the material editor (if you've closed it); and if necessary, click on the timber material. Notice the material's name is listed as Wood-Cedar Boards!
The M stands for "map" which is short for "texture map"!	In the Phong Basic Parmaters rollout, notice the small button with a M, beside the Diffuse colour... click on the button. This has the effect of selecting the material map associated with the diffuse colour and displaying its properties. Notice that the name listed (where Wood-Cedar Boards was) is now Map#2!
	Look for the Bitmap Parameters rollout... within the Cropping / Placement section is the View Image button - click on it!
Many of the materials in VIZ are simply pictures that are "tiled" over an object to create the effect of an object with a particular material. It is possible (and in-fact very easy) to replace the "standard" picture with a new one and thereby create a new material!	The key issue with making materials look believable is working out the size of the "object" in the image. You should be seeing a picture of 10 floor boards. If we assume each board is 100mm width, then the whole view is 1m wide! Armed with this understanding of the "true" physical size of the material map we can calculate the correct scaling.
Select the floor either by clicking on it or by using Select by Name.	Select the living room floor and click on the Modify command panel. Note the width of the box (the floor) is 4250mm. Uncheck Generate Mapping Coordinates - at the bottom of the Parameters rollout - because we're about to explicitly set the mapping...
So, in short, the technique is: (1) calculate the key dimension of the material image, (2) calculate the equivelent dimension of the object, and (3) divide "2" by "1" and the result is the tile setting!	Click on the UVW Map button in the Modifiers rollout. Change the U & V Tile settings in the bottom of the Mapping rollout to 4.25.
	Re-render the camera view and you should see that the floor now looks like the floor of a space about 4m wide!
Have you saved recently?	Once you render this view, you may decide to change the lights a bit!!
Finishing...
	Create a few cameras in the space - looking in various directions...
Select them either by using Select by Name or by picking them!	Apply materials to the other objects in the scene! Either use a 'flat' colour by altering a sample material's diffuse colour or pick a sample material from the material library. If the lights in the lamp shades appear to "leak" through the shades, try converting one from being shadow mapped into raytraced... look in the Shadow Parameters rollout...
By the way, if you right-click on the current sample you get a menu which allows you to see up to 24 sample spheres at once!

Last Update : 8 April 1999 Major Revision : 29 June 1998 SEARCH . FBE SITEMAP		Disclaimer . Webmasters Page Contact : Stephen Peter Email : S.Peter@unsw.edu.au