3d Rendering in AutoCAD R14
The AutoCAD built-in rendering engine:
There are three types of lights which can be used:
Distant light (like the sun)
To locate lights in the drawing, before you pick a point for it, type .xy. That will allow you to set the height of the light. Otherwise, all light locations will be placed at the current elevation (usually 0)To make a brighter scene, make more than one sun (distant light)Spotlight (shines in a straight line only, and requires a target and a location)
Point light (shines in all directions equally, and only requires a location)
Note that when textures are applied to an object, they are applied to the default surface only, typically the plan (top) of the object.
You can adjust the scale of a texture either universally (for all objects) (use the library icon) or individually for each object (use the apply texture icon).
You can make your own materials
under the apply texture icon by clicking on "New". You can even add
images to your texture, but they have to be __.tga files. If you have a
file in some other format, you can convert that file to a ___.tga file
by opening it in Paint Shop Pro, and then saving it as a tga file.
3d Rendering in AutoCAD R14 using straight AutoCAD
1. Start a new drawing using
the A-size template
2. Draw a box for the base using the 3d solid command:
Draw3. Move it down 1ń
<Corner of Box> 0,0,0
<other corner> (pick a point in the upper right hand corner of grid)
Move4. Draw another box with a height of 10 feet
0,0,-1 <RET> <RET>
View11. Save and give drawing a name (perhaps your name)
Type ŃSUNń in Light Name Box
Check Shadow on
Click Sun Angle Calculator
Click Geographic Location
Click on map at Chicago location
Change date to 4/1
Change time to 10:00
Change time zone to CST
Click OK again
Click OK again
Click on word "Render" in white drop-down box and select "Photo Raytrace"
Click box next to "Shadows"
Click on word "Render"
Select several materials
Brown Bumpy Brick
Wood - Dark Ash
Wood - Medium Ash
Wood - White Ash
(hint - you can pick several materials to use by holding the <Ctrl> button down while picking)
Click on White Plastic
Pick the base
Click Dark Ash
Pick one of the objects
Pick another object
Pick the third object
Render15. Change your viewpoint by using the Dview command
Dview16. Save the perspective view -type V<RET> click on the "NEW" button and type in a name in the slot, and click on OK. This way, you can easily retrieve it again.
Select all objects
Slide the cursor to the right or left until you get the right size
Slide cursor around until you get the right point of view, then click the left button of the mouse. This dynamically changes only the camera location, without changing the target. The first changes the altitude and azimuth, the second changes only the azimuth.
At this point you can go back and set the Distance again by typing D<RET>
PA will change your camera and target location without changing the distance.
Z will change the focal length of the camera lens so you can get either telephoto or wide angle views (in effect it changes the Ńcone of visionń). It is good to have a wider angle for architectural subjects ÷ it adds Ńdramań to the drawing.
<RET> will end the perspective program and bring you back to the fa,iliar Command: prompt.
View21. Add more lights -try distant light and other times for sun
In drop-down box click on Spotlight
Type name ŃSpotń in Light name box
Click Shadow On
Click Shadow Options
Shadow Volumes/Ray Traced Shadows
MSLIDE24. Play slides to display sequence of scenes ÷ perhaps do a sunrise to sunset sequence showing how the building will look at every hour.
Give it a name
3d Rendering in AutoCAD R14 with Accurender
1. Create new layers of all objects - name them
Base2. Change each of the objects to be on one of these new layers
Object1: brick7. Click on Lighting button
Object2: bronze, polished
Object3: concrete, pitted, natural tan
How to speed up rendering with AccuRender:
One of the most important jobs of the 3D modeller is to keep the face count down to an absolute minimum. In most cases, a 16 sided polygon will look exactly like a circle - and in some cases 8 will be enough. If the circle is tiny, use a square! In any case, unless you really know how to control the faceting of round objects, don't let AutoCAD and AccuRender do it for you - use lines instead of curves. Think about how many faces you are creating for every object you make. If you make a sheet of glass from an extruded solid, you are creating 12 triangular faces. If you make it from a 3dface, you create only 2 triangular faces. Over a whole building, this can be a massive saving in memory.
Keep your use of raytracing effects to a minimum. By this I mean reflectance, transparency, refraction, depth of field. Only use them if you need them - don't just add 30% reflectance to a material if you feel like it - make sure you will need it - if you can't see the effect in the final rendering, you don't need it.
Procedural materials can get heavy. If you have a granite procedure on top of a blend on top of a mask, and all made into a tile with a granite joint material, the stuff will take ages to render. Use a bitmap instead.
Too many lights in a raytrace-only rendering will cause quite a big slow down. If you have loads of lights, consider radiosity.
Finally, the most obvious one: Don't set your anti-aliasing higher than you need. I believe the consensus is that you will rarely need any higher than the "high" setting. You many find that certain tiled materials look better at higher settings, but in most cases rendering at a higher resolution is a better option. In general you should use "medium" for test runs, and "high" for finals - unless you have a specific reason for the "very high" and "highest" settings.