Manalaysay, Paula Princesa P. and Nicolasura, Rosabella G. 4 0
Enhancement of radiosity using hemi-cube algorithm 6 6 Manalaysay, Paula Princesa P. and Nicolasura, Rosabella G. - - - 22 pp. 28 cm. - - - - - . - . - 0 . - . - 0 .
Undergraduate Thesis:(BS in Computer Science)- Pamantasan ng Lungsod ng Maynila, 2002.
5
ABSTRACT: The radiosity method was developed to account for the interaction of diffuse light between elements in a scene. The model is excellent for generating scenes for interior of environments, which are mostly collections of non-specular objects and the method has produced realistic looking interiors, resulting in a shift in synthesized images towards global realism, rather than scenes as collections of non-interacting, separately synthesized objects. Radiosity methods represent the development of several renderers, the development of physically based shading models, the user of more rigorous computer method, and the continuing tension between interactivity and realism in computer graphics. The use of hemi-cube method in radiosity emphasizes shadows and subtle coloring in the images. The hemi-cube is first divided into patches, and these patches are divided into pixels where the shooting patches are projected. To obtain shadows it needs to have some visibility information, so it knows how much a patch is visible from another patch. One of the most common ways of doing this is to use a z-buffer from a patch. This is where the hemi-cube comes in handy. Though radiosity method using the hemi-cube algorithm is proven to comprise the best result ever, it still has several drawbacks. And these are firstly, the aliasing caused by the regular division of the hemi-cube into uniform pixels. Secondly, the inaccuracy of the calculation of form factor when the distance of the objects with each other reduces to zero. And lastly, the aliasing caused by light sources into the model scence.
5
2 = =
2
2 --0------
6 --0-- 2 --------
0 2 --
--20------
--------20--
--------20--
----2
/ 2
/ 2
/
/
Enhancement of radiosity using hemi-cube algorithm 6 6 Manalaysay, Paula Princesa P. and Nicolasura, Rosabella G. - - - 22 pp. 28 cm. - - - - - . - . - 0 . - . - 0 .
Undergraduate Thesis:(BS in Computer Science)- Pamantasan ng Lungsod ng Maynila, 2002.
5
ABSTRACT: The radiosity method was developed to account for the interaction of diffuse light between elements in a scene. The model is excellent for generating scenes for interior of environments, which are mostly collections of non-specular objects and the method has produced realistic looking interiors, resulting in a shift in synthesized images towards global realism, rather than scenes as collections of non-interacting, separately synthesized objects. Radiosity methods represent the development of several renderers, the development of physically based shading models, the user of more rigorous computer method, and the continuing tension between interactivity and realism in computer graphics. The use of hemi-cube method in radiosity emphasizes shadows and subtle coloring in the images. The hemi-cube is first divided into patches, and these patches are divided into pixels where the shooting patches are projected. To obtain shadows it needs to have some visibility information, so it knows how much a patch is visible from another patch. One of the most common ways of doing this is to use a z-buffer from a patch. This is where the hemi-cube comes in handy. Though radiosity method using the hemi-cube algorithm is proven to comprise the best result ever, it still has several drawbacks. And these are firstly, the aliasing caused by the regular division of the hemi-cube into uniform pixels. Secondly, the inaccuracy of the calculation of form factor when the distance of the objects with each other reduces to zero. And lastly, the aliasing caused by light sources into the model scence.
5
2 = =
2
2 --0------
6 --0-- 2 --------
0 2 --
--20------
--------20--
--------20--
----2
/ 2
/ 2
/
/