From Tim:

Because I've heard Google Sketchup thrown around a couple of times in this seminar, I decided to download it to my machine and give it a try. After going through the tutorials for this tool, I found it to be fairly relevant to the work that we're trying to do in this seminar and an avenue worth pursuing in terms of trying to get out a plugin for it. While not as quantifiable as I would like it to be (you cannot specify the lengths of edges, or the distance between one point and another), it has a couple of features that I would feel are very appealing from an architect's perspective.

First and foremost, it is very easy and fast to build up a concept of a building, product, or whatever model you would like to create. You simply sketch rectangles, circles, and lines with certain snap-helpers (snap to a face, snap along an axis) to align them in an organized fashion, and then create solid volumes by extruding faces. You then deform these bodies by moving and rotating lines and faces. The tutorial literally took me through the steps of building a small, low-resolution house model, and it took me all of ten minutes to complete. Thus, for the first steps in the creative process, Sketchup is great for quick and relatively accurate concept models.

The other feature that is appealing (and unique to Sketchup as far as I can tell) is the personal and realistic touches in its interface. It allows you to model daylight as it traverses across the model, letting you choose the month and time much like the heliodon we went to see in the architecture light room. It also lets you put the camera on the ground at a person's level to see what it looks like from their perspective, which is crucial from an architect's standpoint. While the former pertains specifically to the topic of this course, both of them are features that appear to be specifically tailored to architecture.

I would like to explore (in terms of finding out the ease of developing a plugin) the possibilities of a tool for Sketchup. There is already a ray-tracing plugin for Sketchup Pro, but because I was only able to find a brief description of it online, I do not believe that it models diffuse surfaces using the radiosity model described by Professor Cutler. A small plugin by us that could even give a rough idea of the lighting using a radiosity model could be seen as a great addition to Sketchup suite. In addition, the interface could probably just be the existing one for Sketchup lighting and shadows, or at least be incorporated into it.

From Zachary:

Here is one product that I find very interesting and, seeing as I own the middle-grade version, I thought that I would share it with the class. The program is called Vue d'Esprit 5, and it is a tool designed and produce by E-on software "for the creation, rendering, and integration of natural 3D environments." ( Now, this product offers both global illumination and radiosity, as well as realistic materials (textures) and an interface that is easy to use, unlike many 3d graphics products on the market.

This product could be useful for the class for many reasons. It is capable of importing 3d formats from many of the most widely used 3d modeling programs available. This would be valuable in the case that your model required the precision that only a true CAD program can deliver, but you were not satisfied by the rendering capabilites of said program. Furthermore, as this program is primarily designed with outdoor scenes in mind, the program provides "accurate skies, atmosphere, and outdoor lighting" ( In the first presentation that you gave, you compared both drawn and CG models of the houss (Falling Water, or something of that nature) and compared how pleasing the drawing looked as opposed to the rigidness of the rendering. With Vue, outdoor scenes around the building are easily created to look natural and pleasing.

Now, onto my experiences and impressions of Vue. I am still learning Vue, as I bought it just before coming to RPI, though I have played around with it a little. The modeling aspect is primitive, though usable for many situations. For a complex architectural design, a more comprehensive modeling tool would be needed, but many projects would be possible with only Vue. The outdoor lighting appears to work well, though I am still inexperienced at manipulating it. The image gallery on the website can confirm this.

One potential obstacle is that I do not know if it is possible to set a location, season and time of day to determine where the sun is. Maybe a little scripting could fix this, though it appears that the product is meant to be used more from a visualization/artistic aspect than a lighting simulation.

This is an architecture page:
Here is an image gallery:
Studio Max vs. Vue comparison:

From Yu:


The paper that firstly introduces Radiosity:
Modeling the interaction of light between diffuse surfaces
Goral, Torrance, Greenberg, & Battaile, SIGGRAPH 1984

A tutorial on Radiosity from SIGGRAPH:

This page provides a general overview of lighting algorithms, along with some programming examples:

Radiosity webpages from universities:

From Hui:

I found the following article very interesting. It relates to what we talked about the last time. I think someone said that people who live in warmer climates prefer to use blue-ish colored lights than yellowish lights like we do here in the U.S. This article goes and describes what effects different colors have on us psychologically.

"How does color affect us?"

From Nor:

Hybrid Solar Lighting (HSL) is a green technology that uses a solar concentrator that collects and distributes sunlight from rooftop into the interior building via plastic optical fibers. The research is being done at Oak Ridge National Laboratory that could lead to highly energy efficient ways of lighting building. HSL will not only reduce the electricity used to generate light but it also converts unused infrared energy into electricity that can be use for other things.

Some benefit of HSL is that it improved IR heat removal and management. It also improved optical fibers placement and articulation. With a longer optical path for light and lower entrance angles for visible light entering large-core optical fibers results in much lower overall transmission losses in the accompanying light delivery system. Furthermore, the HSL brings highly preferred full-spectrum sunlight inside building. Full-spectrum sunlight is preferred over incandescent or fluorescent light because it can help realize performance and health benefits for people of all ages.

With this technology, sunlight can be brought in to nearly anyplace in a building. Compare to direct sunlight where we can only get at the side of the building, this is much more efficient way to light up a building with natural resources. Furthermore, with this technology, less glass will be required thus helping in reducing the heat that build up around the window's glasses.

One thing that I like about electric lighting compares to daylighting is that, electric lighting would have nearly same illumination all over the room. With daylighting, the place near the windows seems too bright to me when I sit somewhere else that has little illumination. With this technology, this will not be a problem. With proper installation, each side of a room can have the same illumination level and thus helping reducing glare.

From Sasi:

I was searching about the daylight redirection system and this link has much information about it. Knowledge base of common terms used in Lighting design.

Here are some links which I think are useful for the computer science people implementing the daylighting simulation in software. I did not go through them though, but they seem very relevant.

A practical analytic model for daylight:

Predictive sunlight simulation for the remodeling of the Real Madrid stadium: