Workshop 6 Notes

Workshop 6 notes, Week of October 11, 2007

Perspective, Lighting and Rendering

1. PERSPECTIVE

Create three platonic solids sitting on a rectangle in the ground plane.

Enter "change view perspective tool" from the view toolbar at the top of the front window.

Drag the mouse from the center of the window to the lower-left hand corner, and the perspective view takes hold and becomes increasingly wide angle the further you drag the mouse towards the lower-left hand corner.

Alternatively, the "Define Camera" tool is located in camera tools part of the Visualization module on the right-hand side of the Microstation application window under the task-list options. Invoke the Visualization module first.

From within the visualization module, select the "Define Camer" tool as indicated below. Choose two-point perspective and also choose view 4, the front elevation view.

Work with the dolly camera icon and turn own continuous view updates. Move the camera fowards and backwards by moving the mouse from the center of the view window up and town. Also examine the remaining perspective view controls.

Note the camera view pyramid in the other open views.

3. BASIC LIGHTING SETUP s

Continue with the base rectangle (with ACS snaps on).
Turn off ACS snaps and use the slab tool to place a slab on the rectangle surface (tentative snap a vertice, hit "o" for "offset"and start drawing in the rectangle).
Place three verticle lines at the corners of the rectangle that will serve to locate two spot lights and one point source light (for a fill light, key and back-key light).
Using the " Change Element Attributes " tool (In the main tool palette, 8 th one down on the left side), check off "color" and make each of the three primitives a separate color.
In View Attributes (from pull-down menu upper left corner of view window), check to make sure that "constructions" is checked on so that we can see the light fixtures, and then make sure plane locks are off.
Choose the "define light" tool from the Visualization module on the right-hand side of the Microstation application window under the task-list options.
Using the "Define Light" tool to create lights in the model as follows:
- Make sure the mode is " create" and place spot lights on two of the "poles" on the right-hand side of the model (intensity of 1.0 and 0.75, key and back).
- Create point light (intensity 0.5) on the front left-hand pole.
Check global lighting and turn off solar light by removing the check from the check-box below..
Under View attributes, turn off constructions so as to hide the light fixtures (the lights will still impact the rendering of the model) and to prepare for rendering the model.

4. STANDARD RENDERING

Under the Render tools palette, select a render mode (e.g., "Smooth Shading), turn-on Antialiasing and render.

Explore in tern Wiremesh, Hidden Line, Filled Hidden Line, Constant (Cosine) Shading, Smooth (Gouraud) Shading, Phong Shading, and RayTracing. We will leave Radiosity Modeling and Particle Tracing until later.

Each of these rendering types has some advantages and disadvantages as we will learn to adapt appropriate to particular needs.

Wiremesh
Hidden Line
Filled Hidden Line
Constant
Smooth
Phong (turn off or save shadow maps under Settings>Rendering>General lighting)
Ray Trace
Ray Trace shading type: anti alias

6. BACKGROUND MAP AND DISTANCE CUE

Settings>Design File>Views

Browse for a Background image and check off the box (C:\Documents and Settings\All USers\Application Data\Bentley\Workspace\SystemMaterials\pattern\SkyBlueSmClouds.jpg).
Create Distance Cue as quick way to give atmosphere to rendering.
- Change " Distance cue" to " fog" .
It is also possible to change near distance, density, or far density of fog
- In Settings>Rendering>General menu, can change " Fog color" (pick light blue).
- Change "far density" to 0.75 and, optionally, change "near density" to 0.25.
To turn the background image off background off, go to Settings>Rendering>View attributes or to the the upper left-hand corner view pull-down menu>View Attributes and check the background off.

7. SAVING RENDERINGS

V iew size in Settings>Rendering>View size.
Set to 640x480 (make sure " proportional resize" is off).
Save image file by going to Utilities>Image>Save (check options and save by browsing to folder).
To see image in microstation, go to Utilities>Image>Display .

8. SURFACE MODIFICATIONS

Tools>surface modeling>modify surfaces

Project Trim

Make rectangle in plan and make circle inside rectangle.
Turn off ACS snaps .
Move circle above the rectangle (using the "F" or "S" construction plane).
Use the "project trim" tool on the modify surfaces palette (2 nd icon).
Make sure "orthogonal" and "keep profile" are selected in the trim dialog box.
Click on the rectangle, the circle, and left-click to accept.

Stitch Surfaces

Draw a second rectangle adjacent to the first rectangle of equal width.
Use "stitch surfaces" (4 th icon) to join the two surfaces together.
Click on first object, second object, and left-click to accept.

Construct Trim

Overlap a new rectangle over the second (in effect cutting partway into first).
Use "construct trim" tool (1 st icon).
With"Trim first surface" option selected, pick first and then second surface to trim.
Left-click to accept.

Split Surface

Pick surface with circular projected hole in it.
Select "split surface" tool (8 th icon).
Choose object then corner vertice.
Move, and surface trims accordingly.

Extend Surface

Select the "Extend Surface" icon (9 th icon) and make sure "extend mode" is "tangentia".
Select edge of rectangular surface and move to extend surface size.

Convert Surfaces to Solid

Place rectangle and build 3D elevations to create an "open container".
It is possible to make the sides by clicking on a vertice, moving to the ‘F’ or ‘S’ construction plane, tentative snapping the next vertice and pulling up.
Copy this rectangle to the opposite side, and create the other 2 sides.
Use the "stitch surfaces" tool to join the rectangles together (click all 5 surfaces and left-click to accept).
Use "Convert 3D" tool (3 rd icon), " convert to solid" option, to convert to solid object (click ‘container’ and left-click to accept).

WILL REVIEW DURING THE FOLLOWING MATERIALS DURING THE NEXT WORKSHOP

9. FILE TYPES FOR TEXTURE MAPPING

These files are interchangeable between drawings and are stored outside the .dgn file:

Material Palette File (file extension " .pal" ) –definition of materials. Can be one of three types

Definition by properties [e.g. color]
By procedure [by specific algorithm]
By texture mapping [literally draping image onto a surface]

Materials Table (file extension " .mat" )

References the palette files according to object or a combination of layer and color.

10. SIMPLE MATERIAL ASSIGNMENTS

Settings>Rendering>Materials

Go to Table>Save As to start a new table.
Go to Palette>Open and choose C:\ProgramFiles\Bentley\Workspace\Triforma\atf_us_ncs\materials.
Open " finishes.pal" and assign " flat warm grey" to the slab.
Right-click on the finish.
Go to " Assign," then choose the object. The material should then have a " +" next to it and contain the layer and color of the object selected.
Open palette " glazing.pal" and assign glass to sphere.
Open palette " metals.pal" and assign brass to cone.
Open palette " floors.pal" and assign tile semi gloss to rectangle.
To preserve the new settings, right-click on the table name and save and then on the palettes to save.

11. PROCEDURE TEXT FILE

Settings>Rendering>Materials

Palette>open and go to C:\ProgramFiles\Bentley\workspace\Triforma\atf_us_ncs\materials.
Open " proctext.pal" .
Assign " dutch bond" to brick slab, then render.

12. CREATE MATERIAL

Settings/Renderings/Materials

Go to Palette> New and save " grue.pal" (can right-click to save or rename).
Start new material " grue1" by right-clicking on the palette and clicking " new material" .
Pick base color by clicking on the white square next to color.
Adjust sliders for: Ambient Diffuse Specular Finish Transmit Reflect Refract.
Add bump map by clicking on the " pattern" button and switching the " Map" to " bump" (Use StuccoBump.jpg from C:\ProgramFiles\Bentley\Workspace\Triforma\atf_us_ncs\materials\bump).
Reduce height to 0.50.
Resave palette.
Open up assign materials dialog box (Material>Assign).
Open palette " grue" .
Assign grue1 to cone.
Render.
Reserve for next time.

13 MODIFY PROCEDURE TEXTURE MAP & CREATE YOUR OWN

Palette> Open

C:\ProgramFiles\Bentley\Workspace\Triforma\atf_us_ncs\materials\proctext.pal.

Double click on " brick" .
Double-click on procedure map for brick in assign materials dialog.
Save palette as myproc.pal in your x: drive.
Copy brick (dutch bond) to mybrick (dutch bond).
Hit edit button, change mortar color.
Save palette (note all names unique (palette and material)

14. TRANSPARENT OBJECTS

COPY materials1a directly and files from classes folder.
Relink individual person files

15. TO MAP IMAGE

In the new palette, right-click for "new material" .
Hit the " Pattern" box.
Click on the magnifying glass to browse for image.
Turn off transparent background.
Under "units" make sure it is assigned to "surface" to stretch the image to the surface area (" Master" tiles it in 1"x1" modules).
In the model, build a new rectangle in a new color.
Assign image to rectangle.
Render to view.

16. ENVIRONMENTAL MAP

Table>environment maps

Set environment maps (sky2.jpg).
Select " raytrace.pal" and assign mirror to rectangle.