Lightscape Viewset (Light-04)
The Lightscape Visualization System from Discreet Logic represents a
new generation of computer graphics technology that combines proprietary
radiosity algorithms with a physically based lighting interface.
Lighting
The most significant feature of Lightscape is its ability to accurately
simulate global illumination effects. The system contains two integrated
visualization components. The primary component utilizes progressive radiosity
techniques and generates view-independent simulations of the diffuse light
propagation within an environment. Subtle but significant effects are captured,
including indirect illumination, soft shadows, and color bleeding between
surfaces. A post process using ray tracing techniques adds specular highlights,
reflections, and transparency effects to specific views of the radiosity
solution.
Interactivity
Most rendering programs calculate the shading of surfaces at the time the
image is generated. Lightscape's radiosity component precalculates the
diffuse energy distribution in an environment and stores the lighting distribution
as part of the 3D model. The resulting lighting "mesh" can then be rapidly
displayed. Using OpenGL display routines, Lightscape takes full advantage
of the advanced 3D graphics capabilities of SGI workstations or PC-based
OpenGL-compliant graphic acceleration boards. Lightscape allows you to
interactively move through fully simulated environments.
Progressive Refinement
Lightscape utilizes a progressive refinement radiosity algorithm that produces
useful visual results almost immediately upon processing. The quality of
the visualization improves as the process continues. In this way, the user
has total control over the quality (vs. time) desired to perform a given
task. At any point in the solution process, users can alter the characteristic
of a light source or surface material and the system will rapidly compensate
and display the new results without the need for restarting the solution.
This flexibility and performance allow users to rapidly test various lighting
and material combinations to obtain precisely the visual effect desired.
There are four tests specified by the viewset that represent the most
common operations performed by the Lightscape Visualization System:
| Test |
Weight |
Lightscape functionality represented |
| 1 |
25% |
Walkthrough wireframe rendering of "Cornell Box" model using line loops
with colors supplied per vertex. |
| 2 |
25% |
Full-screen walkthrough solid rendering of "Cornell Box" model using
smooth-shaded z-buffered quads with colors supplied per vertex. |
| 3 |
25% |
Walkthrough wireframe rendering of 750K-quad Parliament Building model
using line loops with colors supplied per vertex. |
| 4 |
25% |
Full-screen walkthrough solid rendering of 750K-quad Parliament Building
model using smooth-shaded z-buffered quads with colors supplied per vertex. |
| Test # |
Weight (%) |
Testing Parameters (Also see default parameters) |
| 1 |
25% |
-qd box -rm LINE -cp VERTEX -wt |
| 2 |
25% |
-qd box -rm QUAD -cp VERTEX -zb -bt 30 -xws 1248 -yws 960 -wt |
| 3 |
25% |
-qd parlment -rm LINE -cp VERTEX -wt |
| 4 |
25% |
-qd parlment -rm QUAD -cp VERTEX -zb -bt 30 -xws 1248 -yws 960 -wt |