A new radiosity approach by procedural refinements for realistic image sythesis

ABSTRACT

According to the rendering equation, the diffuse and the specular components of the outgoing intensity of each surface patch should be solved simultaneously. Rather than establishing a huge set of linear equations defining the unknown directional intensities for all directions and all surface patches, we expand the concept of the delta form-factor which concerns the light energy transfer of a surface patch along a respective direction. As the delta form-factor for non-diffuse surface patches are dependent on the spatial and spectral distributions of light energy, they could not be calculated geometrically. In this paper, we present a new radiosity approach which progressively approximates the delta form-factors and the light energy distributions within a general environment to the correct solution. The nucleus of our approach is procedural iteration. Statistics indicate the potentials of this method for complex non-diffuse environments.

REFERENCES

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INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS

Additional Classification:
  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS
      I.3.7 Three-Dimensional Graphics and Realism
          Subjects: Radiosity

General Terms:
Algorithms, Design, Performance, Theory

Keywords:
distributed ray tracing, form-factors, global illumination, hemi-cube, procedural iteration, progressive refinement, radiosity